Patent ID: 8125625

Claim:
Hard copy re-emission color measurement system, comprising a light arrangement for emitting light, including a first light and a second light, onto a hard copy, a light detector arranged to detect light re-emitted by the hard copy, a light guide to receive the light emitted by the light arrangement and to output the first light and the second light on an at least partially overlapping region of the hard copy, an ultraviolet light monitor positioned opposite a portion of the light configured to emit the second light to detect the second light without the second light having been re-emitted by the hard copy, and a control circuit configured to process the detected re-emitted light, wherein the light arrangement is arranged to separately and simultaneously emit the first light having just wavelengths longer than an ultraviolet wavelength and the second light having wavelengths in the ultraviolet range, such that when the first light and the second light are separately emitted, at a first time the first light is on and the second light is off and at a second time the first light is off and the second light is on.