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The Laser Unprinter
MrSeb writes "You've heard of laser printers — and now a team of researchers from the University of Cambridge in England has created a laser unprinter that can remove ink without damaging the paper. Despite both methods using lasers, their (un)printing approaches are fundamentally very different. In a laser printer, a laser is used to give individual 'pixels' on a piece of paper a positive charge (a separate heat source is used to fuse toner). In the laser unprinter, picosecond pulses of green laser light are used to vaporize the toner, or ablate in scientific terms. The primary goal of unprinting is to cut down on the carbon footprint of the paper and printing industries. Manufacturing paper is incredibly messy business, with a huge carbon footprint. Recycling paper is a good step in the right direction, but it still pales in comparison to unprinting. In a worst-case scenario, The University of Cambridge unprinting method has half the carbon emissions of recycling; best-case, unprinting is almost 20 times as efficient."
I wonder what protections the banks will have to put in place to prevent fraud.
And make sure you have a copy of any contracts you sign. Who knows what shenanigans someone can get up to by modifying the original.
[Fuck Beta]
o0t!
...is avoiding paper in the first place, and instead using digital methods to distribute information.
So what is the carbon footprint for powering the laser?
Ah, electricity from nuclear power. Zero emissions. Unless for the Germans, who are dismantling their nuclear power stations and burn coal instead.
This may work well for office paper. What about the spam mail I get in the mailbox every day? If it works for that, AND it becomes expected that we 'unprint' all paper, what do we do with all the excess household paper? (no, did not RTFA)
No more damn toner! Just change the paper. And, presumably, any paper that is standard size would work in one of these printers, there wouldn't be any propriatary paper. You'd be able to keep using the same printer until it mechanically fails, could probably keep using the same printer for a decade.
Unless they also developed a way to make paper that can not be unprinted without damage, I imagine that unprinting a signed contract that is just a little too fair and replacing everything but the signature with something more to your liking will be far more efficient than regular forgery.
I would bet that if you compared the carbon foot print of "Laser the sh*t out of it" with "Stuff it in a vat and let the microbes have a party", the current technology would win... it doesn't need much (if any) electricity.
If you care about which particular microbes party, and that they party the way you want, I'm curious how you accomplish this without the electricity usually required to create and maintain the required controlled environment. I suspect you're vastly underestimating the effort required to do this, as well as vastly overestimating the power requirements of your typical laser.
"Convictions are more dangerous enemies of truth than lies."
So, how unhealthy would the vaporized toner be? I really don't know. Somebody care to enlighten me?
Yeah, it's true.
Use Gamemaker.
wait for this to be built into printers. It detected text, zaps it, then prints.
The real issue is wrinkled papers.
The Kruger Dunning explains most post on
the current technology would win... it doesn't need much (if any) electricity
Electricity isn't the major factor - total energy is what matters.
Collecting tonnes of paper and transporting it to recycling centres, pulping, cleaning, processing, re-bleaching (we don't like blue-brown paper, we want white paper) and then transporting the finished paper back to where it is used. Calculate the energy in that.
At work we almost exclusively use reams of recycled paper. Print something on it and then sometime later (occasionally minutes later) it goes into a recycling bin. That bin is emptied once a week and the paper will travel 20 miles to a local depot. Where it is recycled and turned into new paper I don't know - but what I do know is that the reams of recycled paper we buy will come from at least 400 miles away (and will have travelled that via a circuitous route involving suppliers, buyers and distribution warehouses). Taking the same bit of paper and running it through a unprinter for 20 seconds and then reuse. Energy wise I don't think there will be any contest, but the numbers would have to be crunched to prove it.
Cyan, Magenta, Yellow and blacK, actually.
If you're going to be pedantic, you have to be right too.
ITs a lot more then that, especially in by any practical measure.
It's not just dumping in the vat. You have pt process it again, you need equipment to move it around, some of the chemicals are nasty, you need to ship the paper to and from the plant.
"I would bet that if you compared the carbon foot print of "Laser the sh*t out of it" with "Stuff it in a vat and let the microbes have a party", the current technology would win... it doesn't need much (if any) electricity."
And I would bet you never worked in recycling plant, not read the article or no how much energy this laser would use.
I would also bet you can' look at anything but the most simplest of diagrams without getting a head ache.
The Kruger Dunning explains most post on
The standard laser printer does not put a charge on paper, it puts a charge on a transfer roller that then transfers the toner to the paper. That toner is then melted onto the paper.
Kodak (and others), used to make dye sublimation printers, where a sheet of plastic with dye on it was whacked with a laser to sublimate the dye directly onto the paper. This had the advantage of being something more than the typical "yes/no" "is there toner there" question, and thus resulted in much better color reproductions. No dithering was required. The major downside, besides cost of supplies, was that you were left with a negative image on the dye sheet, just like the old plastic film typewriters had.
This system sounds like an incredibly wasteful and complicated process. You have to scan the paper to determine where there is toner and sublimate only those spots. If you miss by just that much, you'll char the paper and miss toner. If you put in a sheet of inkjet-printed paper, you'll burn the paper anyway.
Making/recycling paper isn't that hard. This is silly.
Unprint $1 bills, print $100's
No, the problem clearly is that all the non-nerds are so obsessed with cleanness. If all people just stopped bathing and showering, the water consumption would go down considerably! :-)
The Tao of math: The numbers you can count are not the real numbers.
the standard printer colors are Red, Yellow and Blue
Actually they are Cyan, Magenta, Yellow and Black (the latter because mixing black from the other colors tends to give suboptimal results).
The Tao of math: The numbers you can count are not the real numbers.
Professor, I totally had my paper finished but I accidentally unprinted it!
picosecond pulses of green laser light are used to vaporize the toner, or ablate in scientific terms
So all that toner gets vaporized and is now floating around in the air of your office? What could go wrong?
Ceci n'est pas un sig.
Taking the same bit of paper and running it through a unprinter for 20 seconds and then reuse. Energy wise I don't think there will be any contest,
Cost of making laser. Cost of maintenance on unprinter to keep the optical system aligned. Cost of "that unprinted paper looks like crap, I want this document reprinted on fresh paper". Cost of recycling entire unprinter when it wears out. Cost of eyepatches for office staff that try to unjam the unprinter. Cost of disability payments to retired office staff who tried to unjam it twice. Cost of fire department that shows up when someone tries to unprint an inkjet page and paper bursts into flame. Cost of disposing of unprinted toner (you can't just let the vapor out into the room, you know.)
What happens if you get your fingers stuck in the machine when it's "unprinting"! I can imagine it now. office employee: "Hey xerox guy... I was taking care of this paper jam when all of a sudden half my finger disappeared! What do I do?" The xerox guy raises his three fingered hand. "yep, been there - done that. next time unplug it and wait 20 minutes... I found this out the hard way." office employee: "are you giving me the finger?" zeros guy: does a half grin, and unplugs the printer.
one major flawed assumption: that the "unprinted' paper will be used in printers instead of recycled paper. As a professional laser printer repair tech, I can tell you right now that won't happen. Even paper that has just been run through the printer once and left on a neat pile is significantly more likely to cause printer jams than fresh paper that's never been used. Any "savings" (whether carbon footprint, money, or otherwise) over using recyled paper will be quickly consumed by the extra repair trips.
There is no -1 Disagree mod. Slashdot.org/faq defines mod options. USE IT.
Since the laser is green, green ink will reflect the laser and render the device useless.
Seriously, have you ever seen a table of reflectivity of common materials and pigments? Did any green pigment you have ever seen look like a perfect mirror or what?
Ezekiel 23:20
The process sounds interesting but the writer is an idiot.
"we could cut down on electricity usage, CO2 output, and most importantly fresh water, which is growing more scarce by the year."
We're just shooting it all into space, right? It's not the water getting more scarce. It's TOO MANY PEOPLE vying for the same water that causes the issue. Instead of citing the actual problem, overpopulation, writers like this one refer to one of its symptoms, water shortage. As if conservation would do anything but encourage more overpopulation.
Actually, the problem is just like the writer says... fresh water is growing more scarce by the year. Polluted water (water mixed with stuff that's not potable) is increasing by the year. Added to this, we're also space shifting our water reserves from aquifers to rivers and oceans, draining them faster than they can replenish.
We've got a long way to go before the world is overpopulated; however, the current population is doing a great job of making the resources available harder to access. Conservation allows for a HIGHER population; it's not overpopulation unless the population can no longer live within its means (eg, conservation measures can't keep up with demand).
Unless you're really saying that you want to destroy the current ecostructure and get rid of all but a few people, who, even with their machines, are too few to have a lasting impact on the environment.
Spouse in the forest sciences here,
A minor point, but the huge carbon footprint of paper manufacturing is (at least in Scandinavia) deceptive. While paper factories do burn large amounts of wood to boil the fibres into pulp, the emitted carbon is a part of the natural cycle: it gets picked up again by the trees in the mandatory-by-law reforesting step. As long as the forest is kept at a constant size, the net carbon emission is pretty much zero.
(The sulphite and nitrogen emissions are another story, however.)
"Unprint" violates the phonotactic constraints of Latin. Unpossible! Clearly, the antonym of "print" should be "imprint". (Wait. Oh noooooo...)
Bio questions? Ask me to start a Q&A journal. Computer analogies available for most topics!
Just wondering, maybe it will pay for itself in avoided sewage costs.
Gently reply
Can these be used to "unprint" those pesky yellow dot patterns in colour laser printers?
"Nine times out of ten, starting a fire is not the best way to solve the problem." - my wife
I bought a second paper tray for my laser printer ($50) and print on the back side of pages already printed for another purpose. It seems I get enough paper heading for the trash or recycling to have enough to print on the second side. It works better than the proposed solution although not as exciting.
If I used a sig over again, would anyone notice?
Why was a laser "eraser" not a perfectly adequate word for it ?
-- Julien Pierre http://www.madbrain.com/blog
if the laser could burn naked white reflective paper, it would also definitely char the paper under the toner, which it doesn't.
the inkjet print is a good point though (i suspect it wouldn't actually burn, but it definitely wouldn't "unprint"); also, highlighting and pencil/ballpoint annotations, the use of which is a major reason for printing a doc out in the first place. this is not to mention the issues with feeding used paper in high volumes. the laser printer in my office jams several times a day even on pristine stock.
"They were pure niggers." – Noam Chomsky
Noodler's Ink makes a line of fountain pen inks that are specifically resistant to this kind of laser tampering. Great for signing checks and other important documents that you need remain secure from fraud.
http://noodlersink.com/whats-new/wardens-inks/
Thermal power stations use vast amounts of water, as fresh as available, for cooling. However none of it is actually "destroyed", not much is evaporated, and what is used either goes back through a loop again or goes downstream to be used again for something else.
Laser erase YOU!
This sig is not paradoxical or ironic.
It's not about ozone. However unhealthy ozone may be if you inhale it, it's easily dealt with. It's about micro-particles containing cancerous substances. As anybody in the toner-industry can tell you, it's incredibly unhealthy to breath in toner dust. Laser printers come with a plethora of particle filters (at least the professional ones do) so you can actually use them in an office without being exposed to levels of danger anywhere near the average tobacco smoking addict or worse. As long as the proper procedure is followed when doing maintenance and exchanging toner, you don't get a lot of exposure, but if you shoot up the toner particles so fine that they become air born, there may be a whole new problem. It's already proven that micro particles from diesel engines, brake pads and tires near roads are very bad for your health, regardless of the carcinogenic qualities of said particles.
Once you start blasting significant amounts of micro size particles containing known carcinogenics in to the air of the average office, you'll be in major trouble as a manufacturer. This means that a laser-unprinter would probably have to have a very elaborate filtering system set up and special (think asbestos style) removal crews come to do service and maintenance on them.
How many pieces of paper would still look good after the toner would be blasted off? Finger prints, coffee stains and creases would probably still be visible. I doubt you could recycle more than 25% or so of all printed paper. Even worse, for quite a lot of paper it wouldn't be obvious that it doesn't look good enough for re-use until after you've un-printed it.
I was promised a flying car. Where is my flying car?
Laser printers don't use lasers to charge paper, they use them to selectively discharge an image transfer drum, which is then covered in toner and pressed against a piece of paper. The toner and paper are on opposite ends of the triboelectric series and spontaneously develop opposite charges when brought into contact with each other.
As for the toxicity of the toner vapor, the composition is of course proprietary, but black toner historically has comprised mainly oxides of selenium. In small quantities it's probably harmless, but long-term exposure is almost certainly bad for you.
Actually, I wrote my thesis on life experience.
Why don't we make paper out of hemp?
It is official; Netcraft now confirms: The backspace key is dying.
One more crippling bombshell hit the already beleaguered keyboard community when IDC confirmed that the backspace key market share has dropped yet again, now down to less than a fraction of 1 percent of all keyboards. Coming close on the heels of a recent Netcraft survey which plainly states that the backspace key has lost more market share, this news serves to reinforce what we've known all along. The backspace key market is collapsing in complete disarray.
If this works on tattoos, then there's a hundred of million dollar industry about to erupt. The tattoo industry is exploding right now, which means that in about 5-10 years, tattoo removal will be almost as big. Where can I license this technology?
By the inventors of the laser no less. Check http://www.youtube.com/v/CoGsoH2UtMM at 17:18.
Stefan Axelsson
Please send me a quote for 10,000 of your unprinting Machines ASAP
Fraternally Yours
Big Brother
Donte Alistair Anderson Roberts - hi son!
Karma: Chameleon
You laugh now, but wait till they find a way to charge you for them un-cartridges...
Cyan, Magenta, Yellow and blacK, actually.
If you're going to be pedantic, you have to be right too.
The K in CMYK stands for Key, not black.
If you're going to be pedantic, you also have to be correct as well.
http://en.wikipedia.org/wiki/CMYK_color_model