Many people save trees (and some money) by loading one-time-use printouts back into the printer and printing some other disposable content on the other side.

This practice backfires once in a while, however, when something official has to be printed and the other side must not contain any driving directions or short stories from texterotica.

So, printers could have a special warning light or/and beep that would alert the user that a reused paper is being used. This would allow to avoid the hassle of reprinting the official documents and, perhaps more importantly, prevent the embarrassment of sending your business loan application along with the sketches of your evil lair on the other side.
-- xipetotec, Sep 10 2007

Better yet have two paper sources in the printer - one reused, one pristine. At the time of printing you can select one or the other (default is reused). Of course if the reused paper tray is empty, the printer will revert to pristine.
-- Texticle, Sep 10 2007


Yes, that would be ideal -- but smaller home/small office printers tend to have only one paper source, hence the need for an indicator.
-- xipetotec, Sep 10 2007


Particularly important in he bathroom, nethinks.

(The cure, btw, for this and all those cases where idiots leave legal or letterhead paper in after they're done, is simply to print your important stuff on manual feed. Then it will be there at the printer waiting for you to feed the right paper in. Or, of course, to use printers that have multiple trays, and you can use those to distinguish between recycled, presentation, legal and letterhead.)
-- DrCurry, Sep 11 2007


How would the printer know if the paper has already been printed on?
-- BJS, Sep 11 2007


[BJS] Using some primitive image recognition -- e.g. the preview tool for my scanner does recognize where the printed text is and marks that area for scanning by default.
-- xipetotec, Sep 12 2007



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