| 摘要 |
An imaging device is disclosed for projecting individually controllable laser beams onto an imaging surface that is movable relative thereto in a reference X-direction. The device includes a plurality of semiconductor chips each of which comprises a plurality of individually controllable laser beam emitting elements arranged in a two dimensional array of M rows and N columns. The elements in each row have a uniform spacing Ar and the elements in each column having a uniform spacing ac. The chips are mounted on a support in such a manner that 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, when activated continuously, the emitted laser beams of the two chips of said pair trace on the imaging surface a set of parallel lines that extend in the X-direction and are substantially uniformly spaced in the Y-direction. The chips are arranged in at least one pair of rows on the support, and the alignment of the chips within the pair(s) of rows is 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 imaging device further comprises 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 without altering the separation between the laser beams. Each lens system may comprise a single gradient index (GRIN) rod, or a plurality of GRIN rods arranged in series with one another. |
