Patent ID: 9516187
Filing Date: 2016-12-06
CPC Classification: H04N

Claim Text:
1. A laser scanning unit comprising: a light source configured to emit a light beam; a deflector having an oscillation axis and configured to reflect the light beam emitted from the light source, while sinusoidally oscillating about the oscillation axis at a predetermined oscillation angle, to scan a region of a predetermined to-be-scanned surface from one end of the to-be-scanned surface to another end of the to-be-scanned surface with the light beam; and a scanning lens disposed between the deflector and the to-be-scanned surface and configured to cause the light beam to form an image on the to-be-scanned surface, wherein a surface shape of the scanning lens is formed so as to have: the non-uniform-speed scanning characteristics and the image formation characteristics are characteristics in which, when scanning is performed with the light beam for a predetermined unit time period at a position of each image height on a scanning line from the one end of the to-be-scanned surface to the other end of the to-be-scanned surface, a peak value of an intensity distribution of the light beam at each image height is made equal to each other by a combination of both characteristics.