| 摘要 |
PURPOSE:To miniaturize and simplify information recording optical systems by processing plural beams of laser scanning light through a single optical scanner with optical systems such as an F-theta imaging lens, separated cylindrical lenses for every scanning, etc. CONSTITUTION:Laser beams 19, 20 modulated by optical modualators 17, 18 in accordance with recording are expanded to the beams of light of elliptical shapes of a wide width d2 and a narrow width d1 by unidirectional beam expanders 15, 16 consisting of combinations of cylindrical lenses and these beams enter a rotary polyhedral mirror 3. Two sets of laser scanning beams entering at different angles go through an F-theta lens 5 for imaging stopping down the width d2, and are respectively separated by mirrors 13, 14. They are stopped down at the narrow width d1 by cylindrical lenses 11, 12 and focus on a moving recording material 9 without distortion aberration, thereby forming the scanning line light image by micro light spots. Hence, the need for diaphragms, etc. is eliminated and the plural optical recording systems for color recording, etc. are made into the small and simple constitution. |
