Patent ID: 8401408
Filing Date: 2013-03-19
Classification: G02B,H04N

Abstract:
1. An image forming apparatus comprising: a photosensitive body having an image formation area thereon; a light emitting unit configured to emit a light beam; a light deflecting unit including an oscillating mirror configured to oscillate in a reciprocating manner to deflect the light beam to scan in a scanning direction; a scanning lens configured to focus the light beam deflected and scanned by the light deflecting unit on the photosensitive body to form an electrostatic latent image in the image formation area; a light detecting unit which is provided at a single position and configured to detect the light beam directed to outside areas of the image formation area in the scanning direction and output a detection signal; a controller configured to determine a scanning direction of the light beam based on the detection signal; a developing unit configured to supply developer to the electrostatic latent image to form a developer image; a transfer unit configured to transfer the developer image onto a recording sheet; a fixing unit configured to fix the developer image transferred onto the recording sheet, wherein an optical path length of the light beam directed to one of the outside areas, from the light deflecting unit to the light detecting unit is different from an optical path length of the light beam directed to another one of the outside areas, from the light deflecting unit to the light detecting unit, wherein one of a detecting position of the light detecting unit for the light beam directed to the one of the outside areas in an optical path thereof and a detecting position of the light detecting unit for the light beam directed to the other one of the outside areas in an optical path thereof is located closer to the light deflecting unit than an image formation surface of the scanning lens by a first length, and wherein the other one of the detecting positions is located farther from the light deflecting unit than the image formation surface of the scanning lens by a second length equal to the first length.