Method and apparatus for printing monochromatic images using a spatial light modulator having a selectable light source

A method for printing a monochrome image from digital image data onto a selected photosensitive medium selected from a plurality of types of photosensitive media compatible with a printing apparatus, the method comprising:

• (a) enabling a substantially monochromatic light source selected from a set of available light sources in said printing apparatus, said selected substantially monochromatic light source chosen based on said type of said selected photosensitive medium;
• (b) uniformizing a wavefront of said substantially monochrome light source to provide a uniformized source beam;
• (c) modulating said uniformized source beam in accordance with said digital image data to provide an exposure beam;
• (d) incrementally altering a position of a spatial light modulator to dither said exposure beam;
• and
• (e) directing said dithered exposure beam onto said selected photosensitive medium.

An apparatus for printing monochrome images from digital image data onto a selected photosensitive medium selected from a plurality of photosensitive media compatible with said monochrome printing apparatus, the apparatus comprising:

• a light source selector for selecting, from a plurality of light source elements, a monochromatic light source that is suited to said selected photosensitive medium;
• a uniformizer for uniformizing of light emitted from said monochromatic light source;
• a polarizer for filtering said uniformized light to provide a polarized beam having a predetermined polarization state;
• a spatial light modulator having a plurality of individual elements capable of altering the polarization state of said polarized beam to provide an exposure beam for printing, the state of each of said elements controlled according to said digital image data;
• a first lens assembly for directing said polarized beam to said spatial light modulator;
• a second lens assembly for directing said exposure beam onto said selected photosensitive medium;
• a mask disposed in the path of said exposure beam;
• and
• an actuator coupled to said mask, the actuator disposed to provide motion for exposure dithering.

A method for printing a monochrome image from digital image data onto a selected photosensitive medium selected from a plurality of types of photosensitive media compatible with a printing apparatus, the method comprising:

• (a) enabling a substantially monochromatic light source selected from a set of available light sources in said printing apparatus, said selected substantially monochromatic light source chosen based on said type of said selected photosensitive medium;
• (b) uniformizing a wavefront of said substantially monochrome light source to provide a uniformized source beam;
• (c) modulating said uniformized source beam in accordance with said digital image data to provide an exposure beam;
• (d) incrementally altering a position of a mask to dither said exposure beam;
• and
• (e) directing said dithered exposure beam onto said selected photosensitive medium.