Apparatus and method for laser printing using a spatial light modulator

A printing system comprising:

• a laser source to generate a light beam;
• a linear diffractive spatial light modulator assembly to diffract light from the laser source according to an applied electric field;
• illumination optics for focusing the light beam onto the spatial light modulator assembly;
• an image plane having a photosensitive surface;
• imaging optics disposed in a light path between the spatial light modulator assembly and the image plane to expand the light beam and image the light beam simultaneously on a substantially linear portion of the photosensitive surface, wherein the imaging optics comprises (i) a Fourier transform lens configured such that light from each beam component converges around a corresponding point of a back focal plane of the Fourier transform lens, (ii) an optical component for inverse Fourier transformation of light from the back focal plane to the image plane, wherein the optical component for inverse Fourier transformation of light comprises an inverse Fourier transform mirror, and (iii) a filter positioned at the back focal plane;
• and
• a drum covered by the photosensitive surface, wherein the drum is configured to rotate the photosensitive surface such that the substantially linear portion imaged by the light beam is scanned across an area of the photosensitive surface.

A method of printing comprising:

• emitting a light beam;
• focusing the light beam onto a linear diffractive spatial light modulator;
• diffracting the light beam by controllably diffractive elements of the linear diffractive spatial light modulator according to an applied field at each element;
• and
• imaging the light beam from the spatial light modulator to a substantially linear portion of a photosensitive surface at an image plane, wherein said imaging includes both forward and inverse Fourier transformations of light;
• and
• a drum covered by the photosensitive surface, wherein the drum is configured to rotate the photosensitive surface such that the substantially linear portion imaged by the light beam is scanned across a two-dimensional area of the photosensitive surface,
• wherein the emitted light beam comprises beam components emitted by a plurality of laser emitters, and the focusing of the light beam onto the spatial light modulator comprises magnifying each beam component and bending the beam components to different incident angles.