Philips Develops Fluid Lenses

Lars T. writes "Digital Photography Review has a short report indicating: 'Philips Research at the CeBIT exhibition is demonstrating a unique variable-focus lens system that has no mechanical moving parts. Suited to a wide range of optical imaging applications, including digital cameras.' Here is Philips' press release and the Heise News article (in German) where I first heard about it. The latter also mentions that Philips has recently used the same electrowetting effect in an 'ePaper' display prototype."

Comments

I take it as...

[madsenj37]

"Suited to a wide range of optical imaging applications, including digital cameras." I take this to mean that it is not ready for precision applications and that it may not be. either way, this will take time to get any better

Applications to Eyewear

[zalas]

Would it be possible to adapt this type of lens to eyewear by enlarging the size? Instead of using bifocals or trifocals, you might be able to have just one lens that changes shape according to a microcontroller, which is then hooked to either a button, or perhaps tapped into a nerve, which can then be trained to send the appropriate signals.

Re:Applications to Eyewear

[spectrokid]

I guess that if you fill a plastic bag with water you automatically get a lens which has a () shape, as opposed to the )) shape you normally get in glasses. It might work, but you not gone look like the coolest kid on the bloc wearing two fish-bowls on your nose.

Re:Applications to Eyewear

[jpampuch]

Getting larger probably has constraints, though using different solutions may provide some flexibility in size. Gravity alone would probably have a big impact on 'eyewear' sized lenses.

I'd guess that the going much smaller is constrained by capillary action.

Re:Applications to Eyewear

[slash_fossils]

Yes! It occurred to me that my video camera can autofocus over a range that my own eyes can't any longer. Not only that, it can zoom and see in the dark (Sony nightvision). I'm ready for spectacles that can do all that. I'm tired of switching from one pair of fixed focus glasses to another, to trifocals and back. Stop the insanity!

Re:Applications to Eyewear

[stuffman64]

My guess is that it could be possible to cancel the effects of gravity (or other acceleration) on the fluid using the same technology. One set of electrodes would shape the lens, the other would 'hold' the fluid in place.

In my opinion, the biggest thing preventing this from being used in eyeglasses is the fact that the lens must always be as thick as the greatest magnification 'setting' on the lens. Also, since there is at least 4 different indexes of refraction (air, glass, fluid 1, fluid 2), there is a much greater likelyhood of chromatic abberation and other artifacts. But who knows what another century or so of research would do for this technology.

Re:Applications to Eyewear

[Anonymous Coward]

Yes, it would. There was already experiments underway with this about three or four years ago. I'd be very surprised if lenses like that, although not as pretty as these ones, are already in use.

The ones I'm thinking of was developed in particular for under-developed countries. Helpworkers can bring a whole set of glasses and easily and quickly adapt them on site without the need of expensive equipment.

Re:Applications to Eyewear

[stuffman64]

I hate replying to myself, but I forgot something. If you can't scale this up to eyeglass size, why not just replace your *whole* lens with one of these. They are similar in size, and with some nifty bioelectronics, it could learn to focus using the nerve impluses that your brain uses to control your real lenses. Just hope the battery doesn't die when doing something important like driving...

Re:Applications to Eyewear

[stuffman64]

Did you check out progressive lenses, such as these or these? They might be the answer to your eyeglass switching. They sure helped my dad.

Re:Applications to Eyewear

[mikerich]

I guess that if you fill a plastic bag with water you automatically get a lens which has a () shape, as opposed to the )) shape you normally get in glasses. It might work, but you not gone look like the coolest kid on the bloc wearing two fish-bowls on your nose.

About ten years ago a UK charity demonstrated a pair of spectacles for the developing World that used just this principle. The lens were made of two plastic films separated by a small gap. Syringes filled with water (?) could be attached to the arms of the spectacles. The person needing the glasses would put them on, then the syringes would be depressed and water pushed into the gap between the films. When the wearer saw a sharp image, the syringe could be disconnected.

No need for precision lens grinding technology, no need for a trained optician and most of all cheap to make and replace.

Never saw it again, I guess the curse of 'Tomorrow's World' struck this one down.

Best wishes,
Mike.

Re:Applications to Eyewear

[Idarubicin]

If you can't scale this up to eyeglass size, why not just replace your *whole* lens with one of these.

Anchoring it would be a heck of a problem. The repeated accelerations whenever you move your eye would put quite a bit of stress on whatever attachment you use to bind this lens to the eye. I'd be concerned about doing damage to the rest of the eye.

Then you get into the question of powering the device. Hiding a battery in your eyeball is just not on--I don't think--and an external power source would need to have wires...how do you get power to the front of the eye? Note again that they eye moves. Also, you still have to blink.

I'm not saying it's impossible--but we're a long, long way from implanting a device like this.

Re:Applications to Eyewear

[Astrorunner]

They had a snippet about those in Wired a couple years ago -- they were filled with some sort of oil, as I recall. They look like Harry Potter glasses, but they cost, IIRC, about a buck a pop, making them ideal for distribution in Africa and other destitute areas.

Re:Applications to Eyewear

[visgoth]

Rather than spectacles, I'd take full out replacement eyes with said technologies. A power source would be tricky though. Somehow I don't think batteries would cut it in this case. Maybe a compact thermoelectric generator could use body heat to induce a small current? The front portion of the eye could act as a "radiator" since it's exposed to the environment, thus providing the needed temperature differential.

Re:Applications to Eyewear

[AnomalyConcept]

I remember reading somewhere that there was a design for cheap eyeglasses for third-world nations that sort of used this principle, except not as 'high-tech'. The glasses had distortable lenses, probably some sort of plastic or polymer bladder that was filled with a clear fluid. The wearer could turn a knob to adjust the amout of fluid and hence the shape of the lens in order to get a customized 'prescription'. All you had to do was close one eye, turn the knob until what you saw was clear, and then repeat the process for the other eye. Unfortunately, I don't remember where I read about this, and do not have a link to post.

Re:Applications to Eyewear

[Anonymous Coward]

Well, you'd still need an optician. Leaving the lenses tuning to the user could end in a bad regulated lenses or not suitable for that person. Not everyone has common sense or skill for tuning them. This is like automedication.

Re:Applications to Eyewear

[mikerich]

Well, you'd still need an optician. Leaving the lenses tuning to the user could end in a bad regulated lenses or not suitable for that person. Not everyone has common sense or skill for tuning them. This is like automedication.

Is it better for a person living without access - either physical or financial - to an optician to be able to see something, rather than a blur? It's pretty hard to imagine how the myopic amongst us would manage without access to spectacles, contacts and the like.

Here in the UK plenty of charities collect old spectacles for redistribution in the developing World. Personally I imagine the quality of life with improved vision rather than perfect vision must be significant.

Best wishes,
Mike.

Re:Applications to Eyewear

[SB9876]

It's not going to be possible to scale these things up much beyond what they've already demonstrated. The reason is that the curvature is solely determined by the interaction of the liquids with the electrodes on the edges. If the lens gets much larger, most of the liquid will be minimally affected. Look at a glass of water, for example: the water has a meniscus edge where it curves upwards to meet the glass. It looks as if most of the water is flat and the edges are curved but this is not true. In actuality, the entire surface is curved but only the water right by the edge of the glass has enough curvature for it to be visible.

If you want the lens to have a uniform curvature so that it is useful as a lens, the overall diameter of the lens must be less that a certain critical length scale which is the length at which the surface tension effects of the edge are still dropping off in a relatively linear fashion. This is determined by the relative surface tensions of the liquids and the electrodes around the edge. While you can tweak those parameters a bit there will be a practical limit to the lens size and I'm guessing that this model is probably pushing that limit already.

Furthermore, the lens is gonna be kinda crappy - it's actually analagous to the lenses in an electron microscope - magnetic lenses that bend electron paths. You can change the current level to change the focus but the lens itself is not shaped properly for good optics - as a result, electron microscopes don't have nearly the resolution they could have on paper. (by about a factor of 100 or so). This new lens has its shape determined by the interplay of surface tension and it's fairly certain that this shape won't make an ideal lens. The result is that you'll have awful sperical aberration. (probably nasty chromatic aberration as well) The result is that the image quality will be poor.

However, that said, these lenses are pretty cool. For point 'n shoot cameras, cellphone cameras and webcameras, these things would rock. Also, security cameras would probably benefit from being able to focus in a reduced total size as well. Any application where fantastic picture quality isn't necessary would benefit from this.

Another potential application is machine vision. There, the machine can easily be programmed to compensate for the lens distortions. Also, if you replaced the ring electrode with a ring of small electrodes around the circumference of the lens, you could set up an uneven charge distribution. This would allow a lens that has a focal point than can be moved off the optic axis. Not only can you focus, you can also bend the light coming through the lens - an electronic equivalent to a gimbal mount. A robot using these eyes can focus and 'look around' with 10 ms speed. This is a potential killer app for these things.

Re:Applications to Eyewear

[qbwiz]

I've heard of a new technique where they create a new lens in your eye and then fill it with a flexible gel. They than have the muscles of your eye move it, and it acts like a normal lens. That seems like it would work much better than doing something machanically complex (at least for people who still have muscles for their lenses).

Re:Applications to Eyewear

[dandelion_wine]

As long as when I magnify as a babe walks by, the lens refraction makes my eyes appear to google outward like some cartoon lech.

Re:Applications to Eyewear

[Cybrr]

Does adding or removing pressure from your lenses differ that much from saying "better" or "worse" to an optician?

Re:Super DVDs

[0mni]

They have done it, Swinburne Institute of Science made one much larger but the laser required to read it costs many thousands of dollars. (I'm sure other places have made similar things for fun, profit or because they were bored and had nothing better to do.)

New Scientist mentioned something similiar

[Ckwop]

There was an article in New Scientist a few weeks ago about a lense that changed it's focus in response to an electric current, iirc.

It was made of some plastic and I think the current changed the density of the plastic at some point in the structure in order to change the focus.

Of course, the aim was the same: "Make a lense without moving parts" - these guys must have developed a better solution because the Lense was very poor in the NS article.

Simon.

Skepticism?

[screwballicus]

Look at their demonstration photo and ask yourself. Lens the size of the tip of its developer's finger?

Or developer with a finger...the size of a camera's lens!

You be the judge.

This is the last time I fall for the grotesquely-oversized-finger demonstration trick. Fool me once, shame on you; fool me twice...

Re:Skepticism?

[rickbrodie]

Gaaahhh!

I hate to be a "sayings nazi" but I've been seeing this a lot lately on slashdot.

The correct saying is "fool me once, shame on me, fool me twice, shame on you".

Sorry to be so strict. ^_^

Re:Skepticism?

[nacturation]

The correct saying is "fool me once, shame on me, fool me twice, shame on you".

No, it's not. If you get fooled once, it the fault of the person doing the fooling. If you're fooled twice by the same person, the fault is yours for falling for it again. Your way is completely backwards.

Re:Skepticism?

[Anonymous Coward]

No, it isn't. Think about it.

Re:Skepticism?

[leenoble_uk]

Maybe it's like the stupid phrase. "Cheap at half the price." and means the opposite of what it actually says.

Re:Skepticism?

[nacturation]

The most common one being "I could care less" (oh it's possible for you to care less? so you must care a great deal then...), instead of the correct "I couldn't care less".

Re:Skepticism?

[Temporal]

Apparently in Texas the saying is: Fool me once, shame on... shame on you. ... ... You fool me, can't get fooled again.

Re:Skepticism?

[rickbrodie]

Well, the way I always understood it was that if I'm fooled once the fault is mine for being gullible, but if I'm fooled twice, the fault is yours for taking advantage of me. But I suppose both ways make some sort of sense, but my way is obviously better because it is correct :P

Re:Skepticism?

[Anonymous Coward]

Your way is wrong. The other way was said by Scotty on Star Trek:TOS, which makes it official.

Re:Skepticism?

[nacturation]

There's only one way to solve this. Let's have a Google Fight!.

Re:Skepticism?

[Anonymous Coward]

Why isn't the fault mine for taking advantage of you even once? It's only my fault for taking advantage of you two or more times? If I take advantage of you once, the shame should be on me. After all, why would you feel ashamed for being trusting? If I take advantage of you twice, then it's you who got suckered a second time and the shame is yours. And if I fool you a third time, then you're a complete fool for falling for it again.

Re:Skepticism?

[Anonymous Coward]

None of your posts contain well-formed sentences. Is English even your first language?

The press release

[Anonymous Coward]

Philips' Fluid Lenses
Wednesday, 3 March 2004 21:40 GMT

Philips Research at the CeBIT exhibition is demonstrating a unique variable-focus lens system that has no mechanical moving parts. Suited to a wide range of optical imaging applications, including digital cameras. Philips' FluidFocus system mimics the action of the human eye using a fluid lens that alters its focal length by changing its shape. The new lens, which lends itself to high volume manufacturing, overcomes the fixed-focus disadvantages of many of today's low-cost imaging systems.

Press Release:
Philips' Fluid Lenses Bring Things into Focus

At this year's CeBIT Exhibition in Hannover Germany, Philips Research is demonstrating a unique variable-focus lens system that has no mechanical moving parts. Suited to a wide range of optical imaging applications, including such things as digital cameras, camera phones, endoscopes, home security systems and optical storage drives, Philips' FluidFocus system mimics the action of the human eye using a fluid lens that alters its focal length by changing its shape. The new lens, which lends itself to high volume manufacturing, overcomes the fixed-focus disadvantages of many of today's low-cost imaging systems.

The Philips FluidFocus lens consists of two immiscible (non-mixing) fluids of different refractive index (optical properties), one an electrically conducting aqueous solution and the other an electrically non-conducting oil, contained in a short tube with transparent end caps. The internal surfaces of the tube wall and one of its end caps are coated with a hydrophobic (water-repellent) coating that causes the aqueous solution to form itself into a hemispherical mass at the opposite end of the tube, where it acts as a spherically curved lens.

The shape of the lens is adjusted by applying an electric field across the hydrophobic coating such that it becomes less hydrophobic - a process called 'electrowetting' that results from an electrically induced change in surface-tension. As a result of this change in surface-tension the aqueous solution begins to wet the sidewalls of the tube, altering the radius of curvature of the meniscus between the two fluids and hence the focal length of the lens. By increasing the applied electric field the surface of the initially convex lens can be made completely flat (no lens effect) or even concave. As a result it is possible to implement lenses that transition smoothly from being convergent to divergent and back again.

In the FluidFocus technology demonstrator being exhibited by Philips Research at CeBIT 2004, the fluid lens measures a mere 3 mm in diameter by 2.2 mm in length, making it easy to incorporate into miniature optical pathways. The focal range provided by the demonstrator extends from 5 cm to infinity and it is extremely fast: switching over the full focal range is obtained in less than 10 ms. Controlled by a dc voltage and presenting a capacitive load, the lens consumes virtually zero power, which for battery powered portable applications gives it a real advantage. The durability of the lens is also very high, Philips having already tested the lens with over 1 million focusing operations without loss of optical performance. It also has the potential to be both shock resistant and capable of operating over a wide temperature range, suiting it for mobile applications. Its construction is regarded as compatible with high-volume manufacturing techniques.

(A) Schematic cross section of the FluidFocus lens principle. (B) When a voltage is applied, charges accumulate in the glass wall electrode and opposite charges collect near the solid/liquid interface in the conducting liquid. The resulting electrostatic force lowers the solid/liquid interfacial tension and with that the contact angle q and hence the focal distance of the lens. (C) to (E) Shapes of a 6-mm diameter lens taken at different applied voltages.
Prototype FluidFocus lenses

Photos courtesy of Philips

A Glimpse

[novalisg]

Just like the oil lenses in Dune

Re:A Glimpse

[rickbrodie]

Dammit, _that's_ where they had them. I read this headline and thought "but they've had oil lenses for ages, surely". I guess it's going to be another one of those days...

The lens diagrams are wrong.

[numist]

The lenses in the diagrams at this link do not work: link

The first lens has a positive magnification, and the second a negative magnification. The light rays drawn on the diagrams are reversed.

Others should be able to confirm this.

Re:The lens diagrams are wrong.

[moveax]

Depends on which fluid has the lower refraction index. I.e. either the upper-fluid in the diagram can be regarded as the lens, in which case the lines are drawn correctly, or the lower fluid, in which case you are right.

Re:The lens diagrams are wrong.

[Anonymous Coward]

No, if you look at the picture it says that both the brown and the blue stuff are fluids. If the brown stuff is optically "more dense" it'll work this way.

Re:The lens diagrams are wrong.

[Anonymous Coward]

That stries me as entirely too funy right now!! You're absolutely right, though. I wonder who made those images. I'd think someone would have caught this, being that this "dynamic lens technology" is so freakin new!!

Re:The lens diagrams are wrong.

[photonic]

I guess you where sleeping your way through the optics lectures: These lenses could definitely work. If you look at the picture
you see that there are two fluids: brown one on top and a blue one on the bottom. If you remember Snell's law (ray bends towards the normal in the denser medium), you can conclude from the picture that the 'brown' fluid has a higher refractive index than the 'blue' fluid. The left picture thus resembles a hollow/concave/negative lens and the right picture resembles a convex/positive lens. Of these the positive (on the right) can be used to form a real image (one you can capture on a CCD or a retina), whereas the negative only forms a virtual image.

A colleague of mine did his internship at the group that invented these and my boss still works part-time at Philips.

Fixing Eyes With it

[deathcow]

I dont know about scaling it up. The article is short on details which relate much to eyewear. Eyeglasses correct a huge range of flaws in eyes; by far not the least of which is astigmatism, (wildly popular) which is when your cornea is not curved the same in all axis. (For example, your eyeglasses correction may need to be different vertically than horizontally.)

Astigmatism isn't going to lend well to this, would be my guess, but who knows maybe those wizards can make assymetrical fluid shapes.

Secondly, the size.. why make it big? Make it small like contacts (your eyes dialate only to 5 or 6 mm as an adult.) And put it close. Bizarre tiny eyeglasses is the ticket.

Re:Fixing Eyes With it

[richie2000]

astigmatism, (wildly popular)

I don't know about that, I'm not that thrilled about mine. It's actually quite unpopular and not really likely to get voted 'most popular affliction' any time soon. On the other hand, it's rather common.

Re:Fixing Eyes With it

[rsepulveda]

Maybe it cannot be used to substitute eyeglasses, but it can be a good canditate to make a new type of intraocular lens (the ones used to replace the natural lens extracted in a cataract surgery).

The natural lens in the eye can do something called accomodation: change the dioptric power of the eye in order to focus images far away and close up (and in between them :).

When you extract that lens (usually the treatment of cataract) it can be substitued with an intraocular lens, but losing the accomodation, making the patient wearing it to use maximum powered bifocal eyeglasses (+3.00 D) to be able to see in a lecture distance (33cm aprox.).

Intraocular lenses only correct the spherical power, not the astigmatic power of the eye (only the high hipermetropia caused by the cataract extraction). Therefore, if you can implant (and, of course) control this kind of lens, you will be able to have an alternative for external eyeglasses to fix lecture distance.

Of course there are other solutions, but each and every one far from ideal (use "traditional" presbiopic intraocular lenses, which barely work, or having one eye with no graduation and the other miopic.

And to use it in a human eye, you need it to have an optic center of 6mm (average).

Anybody remember these from Dune?

[washort]

Frank Herbert had a similar idea in Dune: he referred to a pair of binoculars having "oil lenses" that were shaped electrically.

Just another instance of science fiction authors' jobs getting harder, I guess.

Re:Anybody remember these from Dune?

[bhima]

Also a sign of a good idea, and a good author. How long ago did he pen that? and it might be practable!?

Re:Anybody remember these from Dune?

[nacturation]

... and did he get a patent? :)

Re:Anybody remember these from Dune?

[Cobron]

Hehe :)

Seriously though:
First thing I thought when reading this article was: "Now this is what patents are all about".
A company that innovates like this deserves to be the only one that may use its' invention and be protected from other companies that would otherwise just copy the specs and immediately compete on the same level.

Re:Anybody remember these from Dune?

[Syberghost]

1965

Re:Anybody remember these from Dune?

[Chief Technovelgist]

See Frank Herbert's Oil Lens for more info and quotes from the book.

cool but i wonder

[lingqi]

ever mix a cup of oil and water? now - there is always a surface between the oil and water since they don't mix, but now, shake the darn thing up and a lot of "oil bubbles" will appear in the watery side, and vice versa. I am sure it will not be good for the optical qualities!

I also noticed that their prototype is extremely small - wouldn't a bigger one be subject to gravitational pull / buoyancy (in respect to eachother) of the liquids depending on lens orientation - and therefore causing a distortion to the optical surface?

Re:cool but i wonder

[Kvan]

I also noticed that their prototype is extremely small [...]

I think that's the point--they're targetting small camera applications: mobile phones, PDAs, keychain digital cameras, clandestine surveillance cameras and such.

Re:cool but i wonder

[Daktaklakpak]

yah, i was thinking the same. another thing too--what about temperature dependency? at some point, the mean kinetic energy of the particles will be able to overcome the hydrophilic-hydrophobic barrier

Re:cool but i wonder

[Anonymous Coward]

Yes, but never the agoraphobic barrier, therefore keeping it in it's place.

Re:cool but i wonder

[Fungii]

You could easily counter the gravity effect by applying an electric field upwards, and as for shaking the lens, if the container is completly full it would be impossible to mix the liquids.

I really like this idea, just imagine how small you could make digital cameras with proper zooms.

News?

[Afrob]

I remember that fluid lenses have been used by holographers for a long time, because they can be of quite high quality even with large diameter. Vari*lite also uses fluid lenses in some of their intelligent lighting fixtures.
The News here is that the Philips lens can be focused by an electric field with no part moving other then the lens. The size of their prototype is tiny; IMHO they need at least to triple the size of it to make it useful for digital cameras.

Re:News?

[JohnPM]

I think the size of the prototype is just right. The real breakthrough application area right now is camera phones. I have a camera on the back of my Sony Ericsson T610 that I've never used. Mobile phone cameras are held back by one massive obstacle: They're currently fixed zoom and fixed focus. Solve that cheaply and a truly massive market is ready made to adopt your solution.

Another fascinating application mentioned in NewScientist's coverage of this stuff is variable zoom security cameras. A security camera could zoom and focus selected portions of the field of view without needing to tilt or swivel the housing. Imagine a kind of moving fisheye effect within the rectangular frame of view. You bolt one of these very cheap cameras to the wall with a very wide field of view and then your operator/software invisibly controls the lens to follow objects closely. Awesome.

Re:News?

[attercoppe]

The size of their prototype is tiny; IMHO they need at least to triple the size of it to make it useful for digital cameras.

Look at the picture at the bottom of the page - the object on the left is one of these lenses attached to - presumably - a CMOS and some related circuitry.

And of course, the solo lens on the right has just come off of the camera used to take the picture, leaving it extremely nearsighted.

Re:News?

[Anonymous Coward]

It seems to me that something like this has already been available for some time from the French company Varioptic. It would be interesting to know if the Philips model offers advantages in terms of chromatic corrections, wavefront quality etc. Or do I sense yet another patent infringement claim comming up?

I think Frank Herbert beat them to it.

[mikeophile]

His novel Dune mentions oil lenses.

I wouldn't be surprised if any authors pre-date Herbert with coming up with liquid lenses. Mr. Herbert is just the one that came to mind.

Artificial Eyes?

[chendo]

Could this be a step for manufacturing artificial eyes? Being able to actually zoom in with my eyes would be cool, and if it has NekkidVision(TM), it would be even better :)

Re:Artificial Eyes?

[Underholdning]

This is very good comment, and in fact an area of very high interest. A few years ago I attended a conference in Holland where a military researcher showed how it, in theory, was possible to give humans extraordinary vision capabilities such as nigh vision, X-ray vision, heat vision etc. Very very exciting lecture.

Re:Artificial Eyes?

[pyrrhos]

I am not an expert in optics, but from what I remember from school, just changing the focal point does not give you zoom capabilities. This just allows you to change your focus. However, this might be interesting for older people who have use dual focus glasses. The problem they have is actually the fact that their natural lens has lost its flexibility and they cannot change their focus anymore.

Re:Artificial Eyes?

[Anonymous Coward]

In order to have a zooming lens, not only the focal length has to change, but also the distance from the lens to the retina. To image something that sits very far away (which is presumably what you want), the distance between the lens and the retina should be almost as large as the focal length, so unless you want to have eyes that are 20cm's in diameter, this won't work.

Seen the GITS2 trailer?

[imsabbel]

Whould be really cool to have contact lenses that enable local zooms into interesting regions, like the static "high magnification" area many birds of pray have in the center of their vision...

Bumpy Car Ride?

[Anonymous Coward]

To me it seems that using such a lense would be bad news in a nonstable environment. E.g. a bumpy car ride.. Any thoughts on this?

Re:Bumpy Car Ride?

[Bearpaw]

To me it seems that using such a lense would be bad news in a nonstable environment. E.g. a bumpy car ride.. Any thoughts on this?

Yeah, two thoughts. First, given the size of the lens, the surface tension of the fluids, and the strength of the electric field, this might or might not be an issue. Second, most current cameras don't perform very well in "nonstable environments". Some cameras have compensating mechanisms (like my now-classic Olympus 2100 Ultra-Zoom), but there's only so much that can be done.

Heck, limits of the human body are factors in such environments, unless you're willing to settle for "point the camera in the general direction and desperately try to keep from banging it against the car".

No, it is probably right

[leehwtsohg]

Depends on the properties of the liquids. On the left, the blue liquid is convex and the brown concanve, and on the right the blue is concave and the brow convex.
So, if light is faster in the blue liquid than in the brown one, the light-rays would move as described.

New spin on something older

[arhines]

A lone researcher did it to make cheap bifocals a few years back. It is an extremely inexpensive way to provide a "one size fits all" pair of glasses for everyone who needs them. No custom lenswork needed - just pump liquid in or out :)

Re:New spin on something older

[Toby O'Neil]

The `lone researcher' is Professor Joshua Silver of Oxford University. The company he formed can be found at http://www.adaptive-eyecare.com/ .

Re:New spin on something older

[djh101010]

They could do with some _diagrams_ on the webpage, it's about as vague as I've ever seen.

Electrowetting

[stor]

Is electrowetting wetting the bed with the Electric Blanket on?

Cheers
Stor

Re:Electrowetting

[Anonymous Coward]

You are George Bush, former governor of Texas, and I claim my $5.

Re:Electrowetting

[Daktaklakpak]

oh SHIT, you know how much that would hurt??!! 110V right up your dick and into your NADS! Someone please please tell me they make electric blankets waterproof...uh not that I care because I don't wet my bed anymore...

...

really, I don't!

...

what's everyone looking at?

Good for photography...maybe

[mikeophile]

Modern photographic lenses have special coatings to reduce reflections from the air gap between two lenses.

For single lens cameras, no coatings are not that big a problem.

For multiple lens cameras, it can lead to a lot of chromatic aberations.

If these oil lenses can accept liquid optical layers, look out Karl Zeiss.

Stop saying "no moving parts", please

[SuperBanana]

Make a lense without moving parts

Everyone keeps saying this. I looked at the diagram, and at least one part of the lens moves. That's a moving part, folks. Stop saying it "has no moving parts".

Now, here are some predictions:

• They'll still break. Electrodes will corrode. Membranes will rupture. Say they discover after extended operation that the first units put a little too much voltage through the lens or something. You get the idea.
• Materials used, such as the membranes, will age. Either becoming stiff, brittle, or simply change properties enough that the lens doesn't focus the way it was supposed to
• the curve won't be as perfect as everyone is hyping and initial cameras will have excessively blurry images, or images that are blurry in parts but not others due to inconsistencies in high-volume manufacturing of the membranes(think LCD screen "acceptable bad pixel count")
• light loss will be significant. Whereas in the glass optics field we have multicoated lenses that are incredibly efficient, none of those coatings could be applied to the materials on this lens, and furthermore, you've got(for each element) 4 surfaces, not two, for light to pass through.
• Color balance will be odd despite calibration efforts, and will change as the fluid/membranes age(probably from UV exposure).
• It will be useless on anything other than consumer point&shoots. The sensor on a Canon 10D DSLR for example is almost twice the width of that prototype they showed, and uses lenses 2-3x larger still.

Re:Stop saying "no moving parts", please

[AaronStJ]

You're right, early prototypes of this product will be flawed. In fact, early prototypes of any new invention will undoubtably have flaws. Nothing new should be invented. Ever. Faced with the fact that nothing will be perfect the first try, we should never innovate or try anything new.

Thank you for showing us the light.

Re:Stop saying "no moving parts", please

[Zocalo]

It will be useless on anything other than consumer point&shoots. The sensor on a Canon 10D DSLR for example is almost twice the width of that prototype they showed, and uses lenses 2-3x larger still.

Actually, it's too small for consumer P&S cameras too if the picture is anything to go by, but it might be workable for disposables and video phones though. I'd hate to think what the accuracy of the lens will be in practice though - it's a fluid, so must have some vicosity, which means it's going to move about, which I would assume would impinge on image quality. Of course, there are other uses for lenses other than in cameras and spectacles where this type of lens might do very well.

BTW, your scaling for the EOS 10D is *way* off - the Philips lens is 3mm across according to the press release, most P&S camera sensors are around 8x6mm, although some are as low as 4.5x3.5mm - the 10D's is more like 23x15mm. As to the glass, for a 35mm camera format the glass would typically be in the region of 40mm-100mm in diameter depending on the type of lens and the location of the individual piece of glass in it.

Re:Stop saying "no moving parts", please

[stuffman64]

good points, however, you mention 'membranes' a lot, but if you read the article or look at the pictures, there are no membranes involved. It is simply two non-miscible fluids with a different index of refraction inside of a glass vessel. The actual device does not change shape, only the distribution of the fluid inside. Also, the electrodes will most likely not corrode because chemists would be sure not to use fluids that would oxidize it.

Re:Stop saying "no moving parts", please

[SB9876]

There are no moving membranes involved. The only moving parts are the two fluids. The lens is formed by a moving interface between the two. Even if some sort of mechanical shock causes this interface to break up, simply wait and the system will eventually re-equilibrate. If you take a container with water and oil and shake it up you just wat a few hours or days and the two fluids will seperate back out again. Since there really *are* no moving parts, this lens should be able to operate over an infinite number of focussings without trouble. At the least, it will be able to refocus a number of times orders of magnitude beyond what a mechanical system could handle.

The electrodes shouldn't have problems with corrosion. First, they don't even have to be in contact with the solution - the interaction is electrostatic and so a Teflon coating could be used. Furthermore, when working with a known solvent, corrosion issues are trivial. It's when making stuff that interfaces with the outside world and biological interfaces with all the associated uncontrolled variables that we still hit problems.

The curve should actually be as perfect as you want*. The interface is created by two imiscible liquids - while there will be some transient ripples from vibration, etc, the overall lens interface will be scratch free. It doesn't matter what the manufacturing quantities are - the lenses will be near perfect - the physics of the liquids will smooth out minor manufacturing defects. The only big concern would be defects in the electrodes (unlikely to be big enough in actuality to significantly affect the lenses) and making sure the correct volumes of both liquids are added. (again a trivial matter with modern liquid handling technology) Even if you do get some defects - its easy to correct. Simply automate an optical testing station where each lens has a light pattern run through it. A sensor looks for abberrations in the otpput light and calculates if the problem is fatal. If not, it calculates the necessary compensation to get proper optical performance. (eg: more or less charge on the elecgrodes for a given focus.) have an EEPROM associated with each lens that stores the correction value - problem solved.
* Note: your point holds in that the curve generated by the liquids doesn't form a perfect lens so you'll get hit with some nasty chromatic and spherical abberrations. These lenses definately WON'T be used for high quality optics.

Light loss should be a non-issue. I might be wrong here but surface reflection is primarily at air/liquid and air/solid interfaces because of the large refractive index mismatch. Here, all of the internal interfaces are liquid/liquid and liquid/solid interfaces. Reflective losses shouldn't happen, making anti-reflective coating unnecessary.

Color balance will only be an issue if the liquids absorb a particular color preferrentially. Since both liquids (at least from the pictures) appear colorless, this isn't an issue. The UV degradation you mention is an issue but simply putting a UV absorbing front coating on the lens should prevent degradation. Overall, the problem should be no worse than what one sees with low cost optics with plastic lens components.

I do agree that this lens won't be practical for anything but low-quality optics. The size is limited by the surface tensions and won't get much bigger than what is being demonstrated. Also, the lens shape is non-ideal and will give poor optical performance regardless of the size since it's shape is purely determined by the interacting surface tensions of the liquids.
What this lens will be wonderful for is low-cost disposable cameras, cell phone cameras and small security cameras where image quality isn't essential and cost/size are the determining factors.
A potential killer app is machine vision. A robot can easily compensate for the lens aberrations computationally. Furthermore, replacing the continuous ring electrode with a segmented one gives the ability to cahge the curvature

It's an eye!

[Zog The Undeniable]

I claim prior art as I have had two of them since 1969. Seriously, one squashy lens (of only moderate performance) with a clever image processing system behind it - as in the eye/brain setup - is probably the way to go for digital applications. Computing power is a lot cheaper than Schott optical glass!

Re:It's an eye!

[Anonymous Coward]

Hey, aren't you on r.b.t.?

Re:It's an eye!

[Zog The Undeniable]

The very same :-)

Stop saying "lense" please

[troon]

It's "lens", plural "lenses". I don't care what your dictionary says.

Stop saying "no moving parts", please-Cateracts.

[Anonymous Coward]

Maybe to all that, but these would be perfect for people who nead thei cateracts removed.

How ironic...

[Ross Finlayson]

That an article about visual clarity would be displayed using white text on a black background.

Folks (and note, in particular, "Arse(sic) Technica"): please stop doing this! You're not being 'cool' - you're just making your text harder to read.

Re:How ironic...

[Anonymous Coward]

Idiot. Light text on a dark background has been proven repeatedly to be easier to read (on computer monitors, at least) than dark text on light. White text on dark blue was the easiest to read out of all of the color combinations tested.

Perhaps this has something to do with the fact that dark colors don't flicker as much on CRTs. Minimize the flicker, even if it isn't percieved, and you minimize the flicker-related eyestrain.

Old news

[sakusha]

Fluidic adaptive lenses have been around for several years. I recall many years ago I read about a tech Academy Award for someone developing a fluidic lens for 70mm movie cameras, it was rather primitive, just a blob of transparent gel sandwiched between two plates of optical glass that could be moved by motors, but he got there first. I can't find a citation since the AMPAS database doesn't search on tech awards.

Re:Old news

[cjameshuff]

The innovation here is that the only part that moves in this lens is the lens itself, or rather the fluids within the lens. No motors, solenoids, or other mechanical parts, the lens itself responds to the electrical impulse. Possibly more controllable and better shaped, definitely more reliable.

Re:Old news

[SB9876]

While the cheap glasses in Africa are a wonderful idea (IMO, engineers spend too much time on expensive, gee-whiz stuff and overlook simple, cheap ideas that would potentially raise the quality of life for hundreds of millions of people), this is a different beast.

The cheap glasses are basically a pair of tensioned water balloons in a cheap frame. (50's fashions appear to be 'in' for the third world, I guess. ;) ) A syringe is used to add or remove water until the person can see clearly - no need for expensive glass grinding or optometrists. Of course, they're crap glasses but it's better than nothing.

This new lens uses electrostatics to manipulate the meniscus between two liquids of different refractive indices. I guess that it's a similar basic idea in the same way that any variable focus lens is the same basic idea but these really aren't the same thing.

Flying Image Quadroids

[Swampfeet]

One step closer to reality...

Electrowetting

[payndz]

This is nothing new. Run enough current through a person and you'll see 'electrowetting' in action! 'Electrosoiling', too.

Why not a spinning liquid lens?

[zakezuke]

A neat and easy way to form a parabola is taking a liquid and spinning it. I've formed parabolic mirrors on my turn table just using ordinary epoxy and spray on silver paint. Not to say this isn't cool, but there seems to be an easier means to achieve a variable focus lens via spinning a clear liquid such as water, or perhaps even a reflective liquid like mercury.

Re:Why not a spinning liquid lens?

[Anonymous Coward]

Try doing that while holding the turntable vertical...

Hermetically closed underwater camera!!!

[pesc]

I am a scuba diver and I always wanted to have a small camera when i dive. The ones you can buy now are quite expensive and fragile. Most models use a underwater housing for a standard digital camera that is quite fragile. There is a rubber O-ring around the enclosure to keep the thing water tight. But sometimes you get some dirt on the rubber and the camera leaks when you are 30m below the surface, spoiling your camera.

So I have always dreamt of a hermetically closed camera. You could fill it with a liquid (oil?) to reduce the pressure stress on the enclosing. (This is what current scuba computers do.) By using a digital camera, you don't have to open the camera to access the film. The problem so far has been how to construct a zoom lens since these vary in volume. This kind of lens seems to fix that problem!

New posibilities

[zaunuz]

It may not sound as a major breakthrough, but it is to me. Think of other things that can be created because of this invention:

• Lenses so accurate that you can focus on almost any distance
• Lenses that can handle alsmost any fall (well, the camera will still die)
• Glasses with auto-focus (good if you switch from a book to TV, like many do)

Frank Herbert: "Dune"

[Frans Faase]

Really interesting invention, but this was already mentioned in "Dune" by Frank Herbert where it talks about oil-lenses, if I am not mistaken.

Liquid Lenses?

[stephanruby]

Sorry Philips, liquid lenses have been done before. You'll have to find a new angle to your story. If you believe the old church stained glass stories*, then glass is a liquid, and we've all seen glass lenses before. (-;

* I don't actually buy the church example, but I just thought I would troll for karma anyway.

Re:Liquid Lenses?

[Anonymous Coward]

Bad meme! Down boy!

While glass technically does flow, that's not the reason that old pieces of glass are thicker at the bottom than at the top. The rates of flow are just much too slow. The reason that they are thicker is because it's damn hard to make perfectly even glass by spinning it, and it's easier to balance an uneven object on its widest base.

So yeah, Don't Buy the Story.

underwater camera

[MikeHunt69]

At first I thought this could be an interesting development in underwater camera technology. Then I realised that you still have to have a bubble of air in front of the lens for it to work.. doh!

Re:underwater camera

[SB9876]

I'm not sure where this 'air bubble' comes into play here. According to the diagrams, there's no air involed in the lens at all. There's a plastic cylinder that contains two different liquids that form the lens. Of course, underwater, you'll have different focal lengths due to the different refractive indexes of water and air but that simply requires refocussing - which this lens is nicely adapted for.

Seen it in use in Africa

[loic_2003]

A man designed some specs that used this technology in order to provide clear sight to the poor masses in Africa. All he did was have two syringes - one for each lens- and he adjusted the lens by pumping in/sucing out liquid as the person looked at some images, then he unplugged the syringes and a valve kept the liquid in and the glasses set to the same level. It's kind of a one-pair-fits-all system where the vast majority of people that needed glasses could use this one system. They sure weren't hot to look at, but no-one gave a crap because people aren't so vain over there! This certainly isn't a new technology.

Re:Seen it in use in Africa

[Anonymous Coward]

Yes it bloody well is... That tech uses moving membranes and syringes, neither of which this requires. All done with voltages.

Re:The physics of lens treatment

[Anonymous Coward]

It's not that bad. The first law of gritsodynamics says the amount of grits in a closed system of always conserved. So, there is no real loss of grits.

One idea for using those

[kasperd]

How fast can you change focus? If you can change faster than the time it takes to take a picture, you could actually use different focus for the same picture. Each pixel could look on the values of a few neighbour pixels to find out when the picture is sharpest in this region and save only the pixel value from that time. Information about the actual focus used could be saved in the alpha channel. Imagine a picture of an object 10cm from you where both that object and the background is sharp.

Re:One idea for using those

[Arlet]

According to the article, it takes 10 ms to focus.

Re:One idea for using those

[Ubi_NL]

Just like doing that with a normal digital camera and a tripod so you can have longer exposure

the lens is not the reason why this is not possible

Re:One idea for using those

[Steffan]

• "Imagine a picture of an object 10cm from you where both that object and the background is sharp."

This is just Depth of Field (DOF). It is largely a function of aperture size. As the aperture shrinks, the DOF expands.

Re:One idea for using those

[SB9876]

Yes, the lens can refocus in basically no time but that's not the primary limitation. What presently limits the speed of taking picutres is the time it takes for the processor to determine whether the image is in focus. Although your lens might be able to change focus in 10 ms, it'll still take a second or two of focuss fiddling for the camera to lock down the focus range for either of those focus ranges. If high speed image processing comes along with a similar time scale, yes, this would be practical.

Actually, an idea just occured to me - you could do all the autofocussing first, establishing the various focal lengths and then hammer out the different shots as fast as the CCD can pull down the data. If you did things that way, your idea might actually work. However, its tempered by the fact that these lenses are very low quality, optics-wise. (they may be flawless but they don't have the optimal curvature for a lens and they're pretty small to boot) Any scheme would have to take into account that these lenses are going to be strictly disposable camera and cell-phone camera material.

For the other respondants:

A tripod would be useful for taking two shots with different focus but relys upon the photographer to take both shots which probably involves a significant delay between those shots. (hence the tripod, I assume) However, it is quite likely that objects in the shot will move in that time period, making it impossible to composite the shots. If the camera can be used to grab two sequential shots within a fraction of a second of each other, the need for a tripod is greatly reduced.

Yes, a small aperture will increase depth of field but at the expense of incoming light. A pinhole camera has everything in focus but requires a very brightly lit scene or long exposure times. IIRC, Ansel Adams used this techniques to get his photos and they required him to use obscenely long exposure times.

Philips rock

[Anonymous Coward]

I can't comment on the technology in the article, but I can say this, Philips NL are the nicest company I have ever worked for. If you are ever considering a job
at this company and wonder about their corporate culture know this... Philips combine technical excellence with an easy going attitude that encourages invention and freethinking.
They pay good wages and have excellent facilities. I was at their Eindhoven unit in 1995
for about 6 months. Even though I was an outsider brought in on consultancy, younger than my work peers, and a foreigner from England, I was treated with respect from day 1 until I left. The Dutch are very friendly, but most importantly straight talking people. I never had to endure hidden agendas and bullshit that pervades US and some UK companies. They are very open and honest. After the first night out drinking beers, I knew how the much people I worked with earned, about their families, houses, lifestyles and ambitions. One of the family straight away. Work was intense but enjoyable, you had the feeling of working somewhere that makes a difference doing proper frontier research. I hope its still like that. I was sad to go. Philips invented the CD amongst other things. They also sponser the PSV Eindhoven football team.
Big up Philips.

A brave new world of imaging!

[Genda]

This is way cool...

This makes a lot of things possible that would have been prohibitively expensive, mechanically improbable, or optically restrictive. A small lense with fast focusing, which is high quality, shock resistent (this would depend on oil viscosity and lenses size), and remarkably cheap to manufacture in large numbers would revolutionize;

* Robotic vision,
* Consumer electronics,
* Security and Research imaging,
* Medical Imaging, and Lense Replacement.

You could cover a robot with cheap eagle-eye imaging devices, create a central imaging system that sews all the images together to produce an ultra-highres 360 degree whole world views. This machine would literally have eyes in the back of it's head. Give the critter broad spectrum vision, and spectrospopic analysis, and this robot could be used for anything from public safety, to mineral evaluation for mining. If you're going to buy a robot, make sure it has "Phillip's whole world vision(tm)".

This makes disposable highres digital cameras and camcorders totally practical. It makes low end devices possible, products for tens of dollars or less, that have the optical features you would expect to find in products that now cost hundreds of dollars. This is especially true if you combine glass element(s) to the lens. You get the power and optical benefit of a glass front lense, a large optical aperture for light gathering, with simple focus and zooming capabilities provided by liquid lenses. A superior lense with a huge list of advantages. Sign me up!

Now that you have a high quality cameras selling for $10.00, you can put them anywhere and everywhere. Imaging for a whole host of purposes becomes ubiquitous (orders of magnitude more prevalent than today.)

Beside giving medical devices better vision, replacing the lense in the human eye, with one that is for all intents and purposes perfect, would be a godsend to millions of people with cataracts, degenerative lense desease, and missing or injured lenses. In the end, this might become so common place, that when you get to that age where folks noadays begin buying multifocal glasses, our descendents will simply get a super lense implant, and have bionic visual abilities that we can only imagine. Would you trade your eyes in for one's that gave you superwide angle and telescopic capabilities? Oh, and for those folks with astigmatic trouble, one could circle the inside of the lense barrel with panels, and apply differing voltages to the panels so as to create a lense shape consistent with any corneal asymetries. This would be the hot new product among the rich and graying!

Genda

Re:A brave new world of imaging!

[dragon8x4x]

Good idea's, but i think you mean insect-eye not eagle-eye.

Hey! COOL!

[Anonymous Coward]

Now the next time I accidently drop my cave pack down a 30 foot deep pit, I won't break my camera lens!

Whoo Hoo!

Technology to save us from ourselves...

Aberations

[]ix[]

Hmmm. I wonder what kind of aberations one could expect from these? Normal lenses are spherical and expensive special-purpouse lenses are hyperbolical, This lens seems more likely to have a Bessel-shape. It will probably work better than the pinhole cameras in modern cellphones but I wouldnt expect them in any high performance imaging equipment anytime soon.

Aberations aside, its always cool to se new technology emerge in the field of visual optics. The field of optical science is realy realy old and still there are many more things to be discovered.

Re:Aberations

[SB9876]

I agree - these lenses seem analagous to the magnetic lenses in an electron microscope - variable focus but lousy from an optical standpoint. Since the curvature is purely determined by the interplay of surface tensions, I'm not sure how one could make the lenses better optically. Perhpas by changing the curvature of the outer wall (instead of using a straight-walled cylender, using a curved cylender like those old-fashioned barrels out of Westerns) That would change the initial contact angle of the fluids with the wall depending on where the meniscus is located and give you an additional term under your control to modify the meniscus curvature.

I'm not an optics jockey, my knowledge is relatively superficial, does anyone know how many terms are needed to generate a good lens? It might be possible to generate a fairly decent lens with the idea I just outlined, at least on the order of a single sperical glass lens in terms of optical quality.

Old news

[Anonymous Coward]

I remember this idea being used 12 years ago in Africa to make cheap glasses.
Anyone need prior art ?

From The Dune Encyclopedia: Oil Lens

[intertwingled]

OIL LENS. Force-field-enclosed hufu oil, used principally in telescopes. Oil lenses -- so accurate that they have yet to be surpassed, eight millenia after their invention -- share with many other enduring pieces of technology an elegant simplicity. Each lens is made up of a layer of hufuf oil (varying in thickness from .5 mm to 1.0 mm) held in static tension by an enclosing forcefield, and is places within a viewing tube as part of a magnifying or other light-manipulating system. Because of the extremely responsive nature of the enclosing force field, the oil layer can be adusted within microns of a desired setting. No other type of lens element approaches such accuracy.

in 7687, Marcus Vander, an Ixian Field Technician (Class 3) was experminenting with the effects of various force fields on compressed fluids. He had chosen hufuf oil (a derivitave of the hufuf plant, a native growth of Ecaz noted chiefly for its oil-filled seed pods) because of its viscosity and near-perfect transparency.

Vander wished to develop some means of transporting liquids using a force field as a container, an invention which would undoubtedly have had a wide array of useful applications. What he actually created -- as he discovered when the suspended oil focused a beam of white light onto his lab counter and melted its finish -- was the first oil lens.

The new lenses completely replaced all older, less accurate types within fifteen years of their entry into the marketplace. Their supremacy was threatened only once, in 8176, when a poor harvest of hufuf pods created a shortage of oil. Fortunately, the season following was an exceptionally good one; it was discovered that the hufufu plant adapted very nicely to cultivation on Yorba. The double cultivation has prevented any further shortages.

Don't we have that already?

[Ambush]

Isn't it 'fluid lenses' that make ugly chics look better?

You know the ones, a few lagers and you generally have a better appreciation of the fairer sex.

;-)

Re:Don't we have that already?

[payote]

SCO owns the patent on beer goggles. They just filed a lawsuit against your post.

Freezing?

[jridley]

It says one of the fluids is aqueous. I wonder if these lenses will be safe to use in low temps. I've had trouble with film cameras in -20*F temps, the film froze and broke.

Also I wonder how gravity affects these in reasonable sizes; seems it would tend to pull the lens downward unless the two solutions had exactly the same specific gravity.

Nit: Singular of "lenses" is "lens". I don't know what a "lense" is but I'd pronounce it "lens-ee" if I had to guess.

What A brilliant Idea and I Should Know.

[perfessor multigeek]

After all, I invented a variant back in '83. NASA should still have copies of some of my drawings.

Of course I designed it for different uses (mostly diagnostic) and had a few added features that they didn't implement. Gonna have to look at their patents and take a gander at the claims.

I wonder if I should sue.

What's *really* funny is that from what I know, DoD may already have patented my beastie for use in SDI, with or without NASA permission.

Hmmmmm . . . . . .

Rustin

Suitability for Precision Use

[perfessor multigeek]

I take this to mean that it is not ready for precision applications and that it may not be.
Well, duh. Think about the vibration concerns. Any movement not only jiggles the thing but it also takes time for it to settle back down.

Back when I designed a version of this w a a a a y back in the early eighties I was quite paranoid about the issue of how do ya keep the thing from accumulating stuff near the resonant frequencies. I'm not seeing anything in the brief English-language piece about this at all. My puppy allowed for the option of changing focal length by changing ring diameter which, oh btw, made things potentially even worse on that front. On the other hand, IIRC, I made a point of the importance of being willing to switch ring materials to optimize for stuff like ability to dampen vibration.
I wonder if they've figured out yet that when you've got a liquid lens that changes properties by changing electrical charge, you can add impurities to the liquid such that charging the liquid, the liquid will change color. Very precise, very neat, and entirely reversable, at least for as many cycles as they would need for a consumer product.

As I mentioned below, I really *am* gonna have to dig up my old drawings and writeup.

*sigh*
This because I have nothing else to do with my time.

Yeah, right.

Rustin

Re:Suitability for Precision Use

[arkanes]

Bet you wish you'd filed for a patent, eh? You could even have keep extending it every few years. Don't worry, your invention doesn't have to actually work or be practical for you to sue someone who finally invents one that is.

Re:Suitability for Precision Use

[Anonymous Coward]

The beauty of a liquid optical substrate of course is that you can use micro pressure variations in the form of sound to shape it pretty much how you like. In a similar fashion to the sonoluminesence
discussed earlier today many emitters around the circumference could superpose their waves to create a volume continuously deformable in 3D.
By changing the signals you could modify the refractive index at will per point. This opens up great possibilities for hybridised optical/DSP systems for telescopes like perhaps for the Hubble2 :)

May I have a patent please sir?

Vibration Problem for Eyewear

[perfessor multigeek]

Well, sorry to repeat myself but no, I'ld guess that the biggest problem for eyewear is that every time the wearer moves the lens deforms.
Picture trying to do something as simple as walking quickly with them on.

Boing-boing-boing goes your focal length and center of mass.

Rustin

Why are the lenses small?

[perfessor multigeek]

I think that's the point--they're targetting small camera applications: mobile phones, PDAs, keychain digital cameras, clandestine surveillance cameras and such.
Prolly not. The real issue is that the smaller the lenses, the more of a role surface tension takes towards creating a uniform surface. Boundary layers between fluids always have a tendency to bow out in one direction or the other. But that "skin" is just half the thickness of one molecule plus it's range of interaction with the surrounding ones. For water, remember your Van Der Waals forces, kids.
In a one centimeter wide tube filled with water, this phenomenon is obvious and dominates the behavior of the interface. In a one *meter* wide tube, everything from little wavelets from vibration (!) to any impurities to, oh, btw GRAVITY[1], will tend to randomize the shape of the interface.

In udda woids, the bigger the surface area, the more random, or at least nonuniform the shape of the "lens".
Getcherself a copy of good ol' Prandtl&Tietjens (Fundamentals of Hydro&Aerodynamics). Your life will never be the same.

[1] It blows my mind that *nobody* on this thread has yet commented on the tendency of gravity to deform such lenses. Gack! Have *any* of you done the thought experiment instead of just believing what you read?
The Phillips device has a second fluid. I would assume in part this is to address that. Betcha that the indices of refraction are very different but the densities are exactly the same.

Rustin

Re:Why are the lenses small?

[SB9876]

Actually, gravity influences were one of the first things that popped to mind but the size scale of these things (3mm) makes the influence of gravity pretty minimal. I'm thinking of a 3mm water drop on a mirror - even though the water is unsupported, the distortion is suprisingly small. This is two liquids - they don't really even need to be that closely density matched - in a closed container. Vibratiosn and shocks are probably a much bigger problem.

I'd guess that the front and back surfaces of the lens are hydrophobic and hydrophillic respectively to keep the two fluids properly oriented in the cannister. Even if the lens gets dropped, I think that you're looking at most ramping the lens back and forth a few times to get the meniscus properly reset and the lens should be ready to go.

Re: Prandtl/Tietjens - thanks for the heads up, it's already on my Amazon wish list.

Military Applications

[HullBreach]

There are some uses for these that aren't necessarily obvious. For a long time the US Military has been researching ways to protect troops eyes from blinding lasers (Lasers that scan for relflective surfaces like eye-balls which they then pulse with enough energy to damage). One Idea that has repeatedly come up was to give the troop a sort of "blind cockpit" to operate from. This would be acheived by making a pair of goggles with high res screens on the inside and an exterior studded with an array of small, inexpensive cameras. By feeding the data from the cameras through a processor then to the troops veiw, you seperate his/her eyes from the danger. This would also allow the troop to have a sort of HUD overlay as well as easily integrated nightvision (IR receptive CCD's scattered amoung the visible light CCD's).

Gravity

[videokef]

This is a cool idea, but would it actualy work ? Any slight vibration would cause liquid to vibrate which is not a very good thing to have in the lens. unless it's somewhere on the satellite. but would it work without gravity ?

Magnifying glasses?

[Anonymous Coward]

Burning ants will never be the same.

Probably pnuematic, not electronic, for eyes

[stuffduff]

If they shape the vessle properly, the change in shape could be pneumatically driven. The real problem is that the current device that will automatically calibrate the focus for you is about the size of your head; not very practical.

For those of us suffering the curse of bifocals there is some hope. There are new glasses with magnetic clip-ons. If we can get the optometery community to mount the magnification portion of the bifocals in the magnetic clip-on, then we can have an easily mofifable full view perscription.

Re:Super DVDs

[Lars T.]

Okay, who modded this Offtopic?

Philips is the inventor of the CD, and plays an important role in the development of DVD and its successors. Now where could somebody use a tiny, focusable lens without moving parts? Multi-layer optical drives, both player and recorder is certainly a valid answer.

Re:Applications to my eyeballs

[mnemotronic]

After the eyeglasses problem is worked out, how about replacement lensess for my hardening, non-focusing, caratactic eyeballs?

Come on nano-tech!

Link Change

[notter]

http://news.bbc.co.uk/2/hi/business/3528757.stm

Not the first...

[doru]

A French company called Varioptic has developed such a lens and is close to the mass production phase.

all I have to say is...

[Schrimnir]

Mmmmmmmm....liquid center

Time Confusion? Too much spice.

[simon_clarkstone]

You ought to stay off that spice, it's addictive.

Liquid Mirror Telescopes

[randomizer]

Plans are to make a Liquid Mirror Telescope (different tech: spinning Mercury) bigger than the Mt. Palomar. I think that the electronic wetting tech will probably show up in hihg-end consumer telescope eyepieces. Current variable eyepieces use mechanical components to vary the gap between multiple elements. This should be easier to manufacture. R.

not that novel

[Anonymous Coward]

this isn't particularly new to the world of optics - a canadian group of astronomers essentially conceived of, and implemented this idea many years ago.

they pour mercury onto a concave surface, and spin off excess until the mercury layer is a consistant thickness. the optical properties of this sort of surface allow for scopes of this sort that are 10's of millions cheaper than usual. clearly not as advanced as philips idea, but a lot of the groundwork has been laid in the past [self-evident i suppose].

Re:not that novel

[Anonymous Coward]

Yeah, it's pretty much the same idea, except that it's a lens, not a mirror. And there are no moving parts. And it's small enough to fit on your finger (or eye). Wait, I guess it is a little different.

Oh, but you mean the idea of a malleable, variable focus lens isn't a new one. Yeah, that's true. I guess those Canadians came up with that idea. Unless you don't count the ones you're using to read this right now.

Re:From The Dune Encyclopedia: Oil Lens

[PassiveLurker]

the oil layer can be adusted within microns of a desired setting. No other type of lens element approaches such accuracy

Sounds like someone needs a good class in optics.

In order to create a lens that meets the *bare minimum* of optical quality - i.e. no destructive interference between different areas of the lens - you need to have your wavefront accurate to within one-quarter of the wavelength you're trying to focus.

Since your average visible photon is in the 500 nanometer range (turquoise light, roughly), you need a lens that produces wavefront accuracy at least to within 125 nanometers (that's .125 microns for the non-metrically inclined).

A lens that's only accurate to within a micron wouldn't be worth its weight in turnips.

And the Heise article translated ...

[pdp0x14]

Liquid lenses

Scientists in Philips' research organization have developed liquid lenses without moving parts, whose focal length can be varied electrically. Prototypes will be on display at CeBIT Hall 21 Booth B02.

Essentially, the lens consists of two liquids in a glass cylinder outfitted with electrodes -- a polar, conductive, aqueous solution and a non-conductive oil. The walls of the cylinder are coated with a hydrophobic material, which causes the aqueous liquid to form a spherical drop under neutral conditions. Upon application of a suitable voltage, the drop takes on a concave curvature, and the lens gathers light. The principle, called electrowetting, was also recently applied by Philips in the design of a new kind of display.

The prototype has a diameter of three millimeters and a thickness of two millimeters. The lens can be switched between a focal length from five centimeters and infinity in ten milliseconds. The prototype has been subjected to more than one million switching cycles without problems.

Re:From The Dune Encyclopedia: Oil Lens

[craXORjack]

Here is another entry from Technovelgy. This one actually references real world research published in Applied Physics plus some early experiments done with rotating blobs of mercury.

Bumpy Car Ride vs Resonse Time

[Moekandu]

Well, sure the liquids could be affected by gravity to the extent that one liquid is denser than the other, but probably fairly minimal from a less than 10G standpoint.

Also, the full flex response time from one extreme to the other is 10ms, comparable to hard drive access speeds. The Panasonic DVX100 (and related) prosumer video camera actually uses servos attached to the optics to adjust for camera jiggle, tweaking it 480 times a second. The system they've developed here does it without the moving parts and has a greater range of motions, even though it at the worst case only changes 100 times a second (10 milliseconds). Due to the fact that most movement corrections are likely to be small, you could probably get an order of magnitude increase in performance for that particular application.

Also with the right control systems, the unit will be able to adjust to movement (both the camera and the object it is photographing) at an incredible rate! To the user, the camera is always focused on the subject, and can change focus faster than you can move the camera from one subject to another. Imagine getting a nice clear focused picture of the asshat running out of the Quikee Mart with a twelve-pack of cheap beer. Why is it that they always steal the cheap tastless stuff?

It's all about the complexity of the control mechanisms. With the right combination, they may even be able to adjust for chromatic aberration and the like.

This is big news. Really.

Moekandu

Asimov had it first

[Y2]

"Gentelmen, I give you the year's supply of water we used to have!" A fluid-optic system was the Maguffin of an Asimov story, which was itself a sequel to another story. I can only come up with the Russian title at the moment .. "?????????" I think it was. "Anniversary"? Yeah, that must be it. (Ugh, that cyrillic doesn't preview well at all. Transliterating: "Godovshchina."

Where I want such lenses: car headlights

[timothy]

Headlight beams are entirely too coarse; I'd love to be able to dial in a perfect throw, depending on road and conditions. Lenses like this would be one good component of the perfect headlight system. Other parts would be intelligent swiveling mechanisms (left and right as well as up and down) and colored gels (or a chemical layer with a variable color) to best match the day and the driver's vision ... but I digress :)

timothy