Researchers Use Lasers to Un-Print Printed Paper

By Douglas Perry
published

Removing printed toner on paper, similar to how we use an eraser to clear pencil writing, is not something entirely new, but there has never been a feasible approach for the mass market.

However, researchers at the University of Cambridge now claim that ultrafast and long-pulsed lasers can be used to save printed paper from the trash bin and prepare it for reuse.

According to a paper published in Proceedings Of The Royal Society A, a 532 nm green laser light with a pulse length of 4 nanoseconds can evaporate printed toner from paper without significantly damaging it. The process works two to three times before damage would become apparent via a slight yellow tint of the paper, the scientists said. They do not claim that the process is perfect, but they believe that they are on a promising path to enable an un-printer at some point.

According to a press release released by the University of Cambridge, the print removal would be much more environmentally friendly than recycling and producing new paper. Compared to recycling, the un-printing process would save an estimated 50 to 80 percent of carbon emissions.

Douglas Perry
27 Comments Comment from the forums
  • arvalin_dakaria
    But would it be cost effective?
    Reply
  • keyanf
    Something tells me fixing the print code so you don't wind up with various pages with 1 line each in the first place is more cost efficient...
    Reply
  • mcd023
    if you have an office that prints and disposes tons of paper, it'd be effective. just be sure not to get them crumpled! how many new paper jams would that cause?
    Reply
  • Marco925
    so now the printer manufacturers have a new product to charge next to nothing for, but make us replace the laser every few weeks for $1000 a pop
    Reply
  • nebun
    arvalin_dakariaBut would it be cost effective?most likely NO
    Reply
  • GenericUser
    It would be really cool if it could somehow store the evaporated toner for re-use.
    Reply
  • livebriand
    Marco925so now the printer manufacturers have a new product to charge next to nothing for, but make us replace the laser every few weeks for $1000 a poplol... right now, my printer claims some of the toner cartridges are low. When it actually decides they're empty, I'll be using a little trick to force it to use it anyway. lol... printer manufacturers love to charge you too much for things...
    Reply
  • Benihana
    livebriandlol... right now, my printer claims some of the toner cartridges are low. When it actually decides they're empty, I'll be using a little trick to force it to use it anyway. lol... printer manufacturers love to charge you too much for things...Oh Brother! I hear you on that! :P
    Reply
  • Genny
    It's far better suited for destroying confidential documents than any sort of 'green initiative'--erase ink then shred. I can see it serving a purpose.
    Reply
  • joytech22
    GennyIt's far better suited for destroying confidential documents than any sort of 'green initiative'--erase ink then shred. I can see it serving a purpose.
    I'm sure that since it damages the paper in a way, they could just find out what the original content was anyway but the smarter thing to do would be to "erase" it with the un-printer and shred it both ways.
    Reply