OPTICAL SYSTEM FOR LONG DISTANCE TRANSMISSION, AND SCAN LENS FOR LONG DISTANCE TRANSMISSION

摘要

PPROBLEM TO BE SOLVED: To provide an optical system for long distance transmission in which beams are projected on an object through a long transmission system by scanning the beams in the initial stage of the transmission system, and a lens therefor. PSOLUTION: The optical system for long distance transmission comprises a laser beam source, a plurality of galvano mirrors for scanning laser beams in a two-dimensional (or one-directional) manner, a scan lens comprising a relay lens LSB1/SBprovided in an optical path behind the galvano mirrors to once condense the laser beams and a collimate lens LSB2/SBto correct the condensed laser beams to parallel beams while the distance between the lenses LSB1/SBand LSB2/SBis set to be the sum (fSB1/SB+fSB2/SB) of the focal length fSB1/SBand fSB2/SBof the lenses LSB1/SBand LSB2/SB, and a plurality of guide pipes to surround the beams, and the distance from the galvano mirrors to the object is set to be larger than 2(fSB1/SB+fSB2/SB). PCOPYRIGHT: (C)2005,JPO&NCIPI