Leading/trailing edge detection system having phosphorescent belt

A printing apparatus comprising:

• a media supply storing print media;
• a phosphorescent belt positioned adjacent said media supply, wherein said phosphorescent belt moves in a process direction to move sheets of said print media delivered from said media supply;
• a light source positioned adjacent said phosphorescent belt in a first location, relative to said process direction movement of said phosphorescent belt, to direct a primary light at said phosphorescent belt before said media supply delivers said sheets to said phosphorescent belt, wherein said phosphorescent belt generates belt-emitted light in response to said primary light;
• a print engine positioned adjacent said phosphorescent belt to receive said sheets from said phosphorescent belt;
• an optical sensor positioned adjacent said phosphorescent belt in a second location, relative to said process direction movement of said phosphorescent belt, different from said first location, to receive belt-emitted light from said phosphorescent belt after said media supply delivers said sheets to said phosphorescent belt;
• and
• a processor electrically connected to said optical sensor, wherein said processor receives an image from said optical sensor and identifies positions of said sheets on said phosphorescent belt based on where said sheets block said belt-emitted light from said phosphorescent belt.

A printing apparatus comprising:

• a media supply storing print media;
• a phosphorescent belt positioned adjacent said media supply, wherein said phosphorescent belt moves in a process direction to move sheets of said print media delivered from said media supply;
• a light source positioned adjacent said phosphorescent belt in a first location, relative to said process direction movement of said phosphorescent belt, to direct a primary light at said phosphorescent belt before said media supply delivers said sheets to said phosphorescent belt, wherein said phosphorescent belt generates belt-emitted light in response to said primary light after said phosphorescent belt moves past said light source;
• a print engine positioned adjacent said phosphorescent belt to receive said sheets from said phosphorescent belt;
• an optical sensor positioned adjacent said phosphorescent belt in a second location, relative to said process direction movement of said phosphorescent belt, different from said first location, to receive belt-emitted light from said phosphorescent belt after said media supply delivers said sheets to said phosphorescent belt, wherein said light source does not direct said primary light to said second location of said phosphorescent belt;
• and
• a processor electrically connected to said optical sensor, wherein said processor receives an image from said optical sensor and identifies positions of said sheets on said phosphorescent belt based on where said sheets block said belt-emitted light from said phosphorescent belt.