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Turn Your 15" Monitor Into 30 Cheap
John Reder writes "Here is a way to get the most out of your PC's monitor for a few bucks. This link will take you to a page that will show you how to build a Fresnel Lens Box with common easy to find items. A Fresnel Lens Box will double the size of your screen making playing things like 3D first person shooters more enjoyable!" Lots cheaper than a new monitor. Wonder what the image quality is like tho. An amusing hack if nothing else.
I've done just this - putting a letter-sized fresnel lens its focal length away from the monitor (for the lens I had, that was ~8 inches). I was able to project the image on to sheets hung across the room. It was kind of neat - I watched some display hacks on my ceiling.
* The image was backwards. This could be fixed in software, but instead I got a mirror and started projecting onto the ceiling.
* The brightness was low. Two reasons: If you make the picture twice as big, it's half as bright (assuming every single photon makes it to the right place). If you're projecting it, you need to be fairly far away to watch it without blocking the light. Secondly, not all of the light coming out of a monitor goes straight out. The bigger the lens, the more light you get...
* Fresnel lenses approximate real lenses. And for an infinately far away source (frying bugs with the sun) they work really good. However, as the angle of the light hitting the lens increases (you get farther from the center) the quality of this approximation decreases (since you're not necessarily hitting the lens part, but will now send light through the ridges). Thus the image was fuzzy around the edges (I assume that's why).
This would work a bunch better with a real lens, except that large lenses are hard to make and heavy and expensive. You could do it with a small lens, but it would be EXTREMELY dim.
Despite all these problems my fool roommate still has a setup like this in the basement. But this is the same guy who spent ~40 hours (and ruined one of my drill bits) rebuilding a crappy $10 avacado-green sofa he took apart months before.
-me
Trees can't go dancing
So do them a big favor
Pretend dancing stinks!
I was in Tokyo in July of this year, and those 60" personal screen glasses are readily available - NTSC, no problems with US TV compatability. If you ever get there make sure to visit Akihabara - a five-block-or-so area full of every kind of electronic thing you can imagine, from the latest consumer DVD to junk shops with dismantled Mac parts or old NeXT boxes. Sony and Olympus are the two brands I tried, all work reasonably well, but if you're the 1000th person that day to try them out it can be an icky experience, especially in a humid Tokyo summer. They have vinyl pads for the forehead :-( Sony I think have one model, Olympus have three.
I could watch a movie quite happily with one of these - I was considering a portable DVD player with a wearable monitor for all the flying I have to do - but it's still not as good as a good 21" monitor for PC use. Apart from the clarity (will we ever see a "virtual" trinitron equivalent?) it is a little too heavy to wear for hours at a time.
Also consider the problem of someone getting your attention. No problem if you have headphones on, they can wave. If your eyes are covered... do you want someone tapping on your shoulder while you're totally immersed in Evil Dead?
Unfortunately there's still no substitute for large amounts of cash when it comes to viewing enjoyment.
Well not Quake, but we played Tekken 2, Gran Turismo, and all other 30 PSX games I have on a 20 foot diagonal screen using a Proxima projector.. Great fun..
Actually the best part was when the cat tried repeatedly to attack the projected images.. Boing.. MEOW... Boing.. MEOW...
Dumb cat..
Actually, what you propose would actually work.
If you can get the sun in between the lens and the sidewalk, then I can believe that the pavement would indeed liquify. A millisecond later the pavement would vaporize. Just after that, the compounds would break apart into their constituent atoms. And then right after that, the hydrogens that used to be in the pavement would fuse into helium.
It would be much safer to put the fresnel lens in between the sun and the pavement, in my opinion.
If tits were wings it'd be flying around.
You may be able to see a bigger screen, but it does nothing for resolution. I don't think that this will harm the large monitor industry any. Trinitron (and the like) still rule the stores!
Brad Johnson
Advisory Editor
Brad Johnson
To bad it will just magnify my 14inch .42 dot pitch up to a 30 inch with 4.44 dot pitch. :)
I know somebody that had a lens like that - he actually heated the pavement up so much that it kinda-sorta liquified. Of course, the lense was about 30" in diameter too...
Anyway... you may want to keep your monitor away from direct sunlight if you use one of these, lest you burn a hole through the tube!!!
--
As an added bonus, your computer looks like something out of Max Headroom or Brazil.
Besides the whole contraption looking pretty ugly...
Fresnel lenses features concentric rings of angled plastic. The problem is that at the edge of each ring, there must be a compensating drop in the plastic.
Your RGB monitor still constructs pixels by putting red, green, and blue phosphor triads adjacent to each other. If a fresnel edge falls across these triads at an angle, you'll get uneven magnification of the given color (i.e. for a white background, you'll see red, green, and blue patterns at the fresnel edge). Put a drop of water on your screen -- same icky effect.
Not too good.
Granted, your viewable surface may now be 30 inches diagonal, but you're stuck with whatever resolution the monitor supports. Trust me, 640x480 doesn't look any better on a 21' monitor, only larger. If you really want to upsize cheaply and don't want to waste that that Fresnel lens, move the monitor closer. Same effect, even less money. Use the lens to do more constructive things; here's a few ideas you might try..
Use the lens and a mirror to test your employers fire sprinklers.
Slip the lens under the glass of your office copier. No one will able to figure out why their copies come out backwards and HUGE.
Small animals and your fresnel. 'Nuf said.
Read the fine print on your Microsoft end user license. The part about 'your soul' and 'eternal damnation' is especially interesting.
Peel the paint of your pompous neighbors new BMW. Serves him right for making your 1982 Chrysler look bad.
You can have hot coffee sans electricity.
Use it to make eight foot high shadow puppets on your roommates wall at night. Sound effects are optional, depending on the scare level of the individual involved.
Did I miss any good ones?
.sig: Now legally binding!
All you would need to do is figure a way
to use a typewriter as your keyboard.
The world needs more pneumatic message tubes.
Heck, 21" monitors aren't even *that* expensive anymore. I got my 21" Sony 520GS for $500.
- A.P.
--
"One World, one Web, one Program" - Microsoft promotional ad
"Remember when the U.S. had a drug problem, and then we declared a War On Drugs, and now you can't buy drugs anymore?"
Well I don't remember Beyond 2000 _promising_ us anything (I do miss that show though) but there have been many products over the years that brought Head Mounted Displays (HMDs) to the consumer marketplace (I'm not even going to get into scientific/educational HMDs here).
All of them have been plagued by motion sickness, dizyness, and eyestrain, not to mention, especially in the consumer marketplace, unrealistic expectations (chalk it up to hollywood and a populace ignorant of technology).
I figure my eyes have gotten bad enough I'm hoping for the full on cyber replacements but that's an even more off topic post.
Anyway, for the momment being my favorites are the Sony Glasstron's mentioned in the post above. Keep in mind there are two models, the Glasstron PLM-S700, which is capable of 800x600 resolution meant for computers, and the Glasstron PLM-A55, which does 800x225 and is meant for portable DVD playback personal widescreen style.
Sony's Pages are:
PLM-S700 PC Glasstron
PLM-A55: Silly bastards have them under camcorder accessories...
An excellent source I found for these and other HMDs is Mindflux though keep in mind prices there are in Austrailian Dollars.
And BTW, I remember a DOS program called Acidwarp that if you used a certain command line switch would dump out several pages of text intructions on how to build exactly this type of device for projecting it's visuals onto a wall.
There is nothing new in the world, only new implementations of old ideas, and newbies discovering the same old shit.
Besides, seeing Windows boot up on such a large screen must be the stuff of nightmares. :)
"There is no surer way to ruin a good discussion than to contaminate it with the facts."
I did this to turn a tiny portable TV into a 14" screen. Don't expect great image quality, as you are magnifying the monitor's defects and limitations, too. The viewing angle is very narrow. Maybe two (very friendly) people can watch the screen without seeing an edge get cut off. The circular pattern, extra glare, and extra blurriness can give some people a headache, too.
"Sorry, babe, in order for you to see it too we need to squeeze closer together. Yah, just like that...."
..and frankly, it's not a very good hack. The room has to be pitch black in order for you to be able to see an image, and the resolution is terrible. If you want a big projected image, you'll have to buy a real projector in order to get any worthwhile results.
Brazil just happens to be on ShowCase right now. For you americans, it's a station that plays a lot of foreign/domestic shows and films, mostly really good.
This showing of Brazil came on right after Quadrophenia (nothing beats watching Sting kicking the crap out of cops).
It's quite a coincidence this story came up when it did. The fresnel enhanced monitors in Brazil would definitely drive me nuts.
Then again, lenses would be least of my troubles in that particular dystopia.
When the first TV sets came out (back in the 30s I think) their screens were really really small. To compensate for this, some TVs came with special lens which were like 15 inches in diameter and had to be filled with water (solid glass lens this size weights and costs too much). These lens were suspended in front of the TV screen and that's how you watched TV.
Kaa
Kaa
Kaa's Law: In any sufficiently large group of people most are idiots.
6.) Mount the Fresnel Lens Box on the front of your monitor so that the lens is positioned about 6 inches in front of your screen.
[...snip...]
You will notice that you will be placing your face really close to the lens and you may actually have to move your head to look up and down at the four corners of the screen. I read this as:
A: Eye strain from your eyes being too close to the monitor, and reading through a lens (glasses excluded, has anyone tried reading though a magnifying glass for a long period of time?).
B: Neck aches/injury, from "mov[ing] your head to look up and down at the four corners of the screen" All in all, it sounds like a pretty painful way to get a blocky image.
---
Stephen L. Palmer
http://midearth.org
Just another BOFH.
Still missing 2 images, hopefully they'll be up soon.
http://users.intercomm.com/ajones/fresnel/fresnel. htm
Is another link, this one provides more links including where to buy high quality Fresnels.
Kintanon
Check out JoshJitsu.info for Brazilian Ji
When I was a kid I saw something like this at Sears, or JC Penny or some other department store. But, they had a floor model 21" TV Mag'd up to something like 40". It was Kinda cool because it made the picture bigger for like $100 or something, but the down side was that it was like DSCAN LCD display. You had to be DIRECTLY in front of it to see the image clearly.
I'd rather save my cheddar and my time to do some other worthwhile upgrade to my system.
I'm still waiting for the eye glasses that simulate a 60" display that those bastards from Beyond 2000 promised us.
LK
"Hi. This is my friend, Jack Shit, and you don't know him." - Lord Kano
Site is /.'ed, so this might be redundant...
:) A 12"x14" mirror was only a few bucks, too.
I've actually done this before (a long time ago). A mirror, a lens, a box, and an old monitor and voila! But it's not as K-RAD as you might expect.
You lose A LOT of brightness from the expansion (imagine the brightness of a 14"er spread over a 6'x6' square!), from lens impurities (it's plasitc for christs-sake!), and from 'leakage'. This last one will KILL this project. If you try this, make SURE you enclose the box and paint it with matte black paint on the inside. Turn the brightness on your monitor up FULL-BLAST (BEWARE: I'm convinced this is what killed 1024x768 on my 14" throw-away). Also, close all your windows and shut off all the lights. Ambient light will force your pupils open and you won't be able to see the screen clearly.
The lens was $3 (!) at the local surplus store. My brother tells me it can double as an asphalt melter, but I've never tried.
I use this setup to have a CTHUGA box (486 w/ DOS, no flames, please) playing constantly in my living room. It's a very entertaining thing for me and my friends when it's all fired up, and with a program like Cthugha, the slight blurring kinda works to it's advantage. (if you've never seen/heard of Cthugha, you've missed the coolest thing I've even seen on a computer: http://www.afn.org/~cthugha )
Not exactly perfect for games, but definitely a fun geek project for a weekend. If anyone has any questions, don't hesistate to email me.
Bart "We don't need no stinkin' accounts" Grantham
grant_b@cs.odu.edu
PS - Add MAME to the mix and rock on out with some Ms PacMan. Don't deny that is what computers are for!