[Jay] hacked a Blu-Ray laser diode into a keychain enclosure. He found a heavy brass keychain light from Lowe’s and stuffed the diode and a larger battery inside. The existing batteries weren ...

While [Micah] want’s to use these Blu-ray drives for laser graffiti, there are a number of other slightly more useful reasons for the build. With a DVD drive, you can hold a red blood cell in ...

A semiconductor laser ... Blue light-emitting diodes (LEDs), a related technology, were also difficult to manufacture, but became practical and widely used after the turn of the century. See Blu ...