Patent ID: 6498685
Filing Date: 2002-12-24
Classification: B81C,B82Y,F25J,G02B,G03F,G21K

Abstract:
A printing exposure apparatus comprising a radiation source, an illumination system, a modulator mechanism, a printhead, and a scanning mechanism, whereinthe printhead comprises a printhead aperture and an array of printer pixels distributed across the printhead aperture, each pixel comprises a sequence of corresponding microlenses, which are symbolically designated as L1, L2, . . . , LN, wherein N is an integer greater than 1, the illumination system conveys radiation from the radiation source to the printhead, whereupon the first microlens L1 in each sequence receives illuminating radiation, each microlens Lm other than the last microlens LN in the sequence focuses the illuminating radiation onto the next corresponding microlens Lm+1, the last microlens LN in each sequence focuses the illuminating radiation onto a corresponding focal point on a printing surface, the modulator mechanism modulates the radiation, whereby the focal points' exposure intensity levels are controllably varied, the modulator mechanism is a spatial light modulator comprising an array of modulator elements, each pixel further comprises one such modulator element disposed between that pixel's microlens L1 and the printing surface, the exposure intensity at each pixel's corresponding focal point is modulated independently of other pixels, and the scanning mechanism establishes relative motion between the printing surface and the printhead in synchronization with the modulator mechanism as the printing surface is exposed, whereby a synthesized, high-resolution exposure image is formed on the printing surface.