| 摘要 |
PURPOSE:To perform inclination correction and equal-speed scanning with compact constitution by permitting an optical system, consisting of a spherical single lens and a toric lens which scan luminous flux image-formed linearly on a deflection reflecting surface on a medium to be scanned, to meet prescribed requirements. CONSTITUTION:Luminous flux emitted from a light source 1 forms an image lenearly near the reflecting surface 3a of a deflector 3 through an image-formation optical system 2. The deflected luminous flux forms an image on a medium 6 to be scanned through a complex system of a spherical single lens 4 and a toric lens 5 and the scanning speed is kept constant. A forcal length fP on the deflection surface of a deflected-light image-formation optical system is at right angles to the deflection surface and so set that 4.0<=fP/fV<=5.0, where fV is the focal length in the surface of the single lens 4 containing the optical axis. Consequently, even if the reflecting surface 3a slants to a position 3a', image formation is achieved on the medium to be scanned as shown by the broken lines. Thus, inclination correction is made and equal-speed scanning is carried out with the compact constitution. |
