Patent ID: 6980280

Claim:
A two level image writer for forming an image from digital data onto a photosensitive medium, said apparatus comprising: an illumination system in a first level for providing incident light beams, said illumination system comprising: a first source for emitting a first polarized light beam having a first color; a second source for emitting a second polarized light beam having a second color; a third source for emitting a third polarized light beam having a third color; fold mirrors for directing each beam to a second level; three polarizing beamsplitters on said second level which receive said polarized beams from said fold mirrors, wherein each polarizing beamsplitter isolates polarization states of each of said first, second, and third polarized light beams; three spatial light modulators on said second level, each comprising an array of pixel sites, wherein each pixel site modulates said first, second, and third polarized light beam from said polarizing beamsplitter prisms to form an array of image pixels according to said digital data; a dichroic combiner for combining said three modulated light beams into a single writing beam; wherein said first, second, and third light sources include respectively a red Light Emitting Diode (LED) array, a green LED array, and a blue LED array; and wherein said spatial light modulators are reflective Liquid Crystal Devices (LCD).