摘要 |
<p>A preobjective scanning optical system for use with a rotating mirror scanner employing LEDs or lasers to electronically reproduce photographs. The optical system includes a doublet disposed before the mirror and a triplet disposed after the mirror. Instead of collimating, the first optical system along with the mirror forms a virtual, curved image of the LEDs or lasers as the scanner rotates and includes a first and a second lens which, in combination, correct the image for on-axis spherical and axial color aberrations. The triplet has net positive power and its three lenses, in combination, correct for off-axis aberrations such as astigmatism, coma, and lateral color aberration but can be under corrected for field curvature because its object is the curved virtual image.</p> |