| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To enhance the accuracy of regulation of optical axis fluctuation in a laser beam, in a direct writing device. <P>SOLUTION: Beam expanders 20, 30 and 40 are provided on the optical path of the laser beam coming from a light source 10 of a solid laser. The laser beam passing the beam expander 40 is guided to a scanning optical system, composed of a polygon mirror 60 and an fθlens 70 via a collimator lens 50. A parallel flat plate 100 for canceling fluctuation components, in which an optical axis of the laser beam is shifted in parallel with a reference optical axis OP, is arranged between the beam expanders 20 and 30. A parallel flat plate 110 for canceling fluctuation components, in which the optical axis is inclined with respect to a reference optical axis OP is arranged between lenses 31 and 32. A shift position sensor 120 for detecting a shift component of the optical axis is arranged behind the parallel flat plate 100 and in front the beam expander 30. A tilt position sensor 130 for detecting a tilt component of the optical axis is arranged behind the parallel flat plate 110 and in front of the lens 32. <P>COPYRIGHT: (C)2005,JPO&NCIPI</p> |
