| 主权项 |
1. An imaging device for projecting individually controllable laser beams onto an imaging surface that is movable relative thereto in a reference X-direction, the device comprising:
a support; a plurality of semiconductor chips coupled to the support, each of the chips comprising a plurality of individually controllable laser beam emitting elements arranged in a two dimensional main array of M rows and N columns, the emitting elements in each row having a uniform spacing Ar and the emitting elements in each column having a uniform spacing ac; the chips being arranged in at least one pair of rows such that the main array of each pair of chips that are adjacent one another in a reference Y-direction, transverse to the X-direction, are offset from one another in the X-direction, and such that the center of each two Y-direction adjacent laser beam emitting elements in the main arrays of both chips in the pair be uniformly spaced from one another in the Y-direction by a nominal distance Ar/M, and wherein the centers of laser beams emitting elements of both chips do not overlap in the Y-direction; the chips within the two rows of the pair being aligned such that corresponding elements in any group of three adjacent chips in the X and Y-directions lie at the apices of congruent equilateral triangles and the distance in the Y-direction between corresponding elements equals nominally to N·Ar, where Ar is the nominal distance between the centers of any two adjacent laser beam emitting elements in each row; and, a plurality of lens systems, each serving to focus the laser beams of all the laser elements of a respective one of the chips onto the imaging surface, each lens system comprising at least one gradient index (GRIN) rod. |
