| 摘要 |
PROBLEM TO BE SOLVED: To provide a light scanning optical system and a multibeam scanning optical system that a printing position is not deviated in a main scanning direction and accurate printing quality can be obtained and image forming device using it. SOLUTION: This light scanning optical system is provided with a first optical system 12 shaping luminous flux emitted from a light source means 1 and forming the image thereof as the linear luminous flux being long in the main scanning direction, a light deflector 5 having a deflecting surface near the image forming position of the optical system 12 and deflecting the incident luminous flux in the main scanning direction for scanning, a second optical system 6 forming the image of the luminous flux reflected and deflected by the deflector 5 on a surface to be scanned and making relation between the deflecting surface of the deflector 5 and the surface to be scanned almost conjugate and a writing start position synchronizing signal detection means 11 controlling the timing of a scanning start position on the surface to be scanned by using one part of the luminous flux reflected and deflected by the deflector 5. Then, a luminous flux restriction means 8 restricting one part of the luminous flux made incident on the detection means 11 is arranged in an optical path between the deflector 5 and the detection means 11.
|
