Scanning optical system
AssigneePENTAX Corporation
InventorDaisuke Koreeda
Life of this patent
Estimating the term…
Abstract
There is provided a scanning optical system, which is provided with a deflector that deflects the plurality of beams, and an imaging optical system that converges the plurality of beams deflected by the deflector to form a plurality of beam spots on surfaces to be scanned, respectively. The imaging optical system has at least one lens whose position is changeable in a plane including an optical reference axis thereof and parallel with the main scanning direction. In this configuration, the imaging optical system satisfies a condition: 0.05<|f/fL|<0.5, where, f represents a focal length of the imaging optical system in the main scanning direction, and fL represents a focal length of the at least one lens in the main scanning direction.
Claims16
A scanning optical system for emitting a plurality of laser beams scanning in a main scanning direction, comprising:
- a deflector that deflects a plurality of laser beams to scan in the main scanning direction;
- and
- an imaging optical system that converges the plurality of laser beams deflected by said deflector to form a plurality of beam spots on surfaces to be scanned, respectively, the plurality of beam spots scanning on the surfaces to be scanned in the main scanning direction, respectively,
- wherein said imaging optical system has at least one lens whose position is changeable in a plane including an optical reference axis thereof and parallel with the main scanning direction,
- wherein said imaging optical system satisfies a condition:
- 0.05<|f/fL|<0.5
- where, f represents a focal length of said imaging optical system in the main scanning direction;
- and
- fL represents a focal length of said at least one lens in the main scanning direction.
A laser beam printer employing a scanning optical system for emitting a plurality of laser beams scanning in a main scanning direction,
- said scanning optical system comprising:
- a deflector that deflects a plurality of laser beams to scan in the main scanning direction;
- and
- an imaging optical system that converges the plurality of laser beams deflected by said deflector to form a plurality of beam spots on surfaces to be scanned, respectively, the plurality of beam spots scanning on the surfaces to be scanned in the main scanning direction, respectively,
- wherein said imaging optical system has at least one lens whose position is changeable in a plane including an optical reference axis thereof and parallel with the main scanning direction,
- wherein said imaging optical system satisfies a condition:
- 0.05<|f/fL|<0.5
- where, f represents a focal length of said imaging optical system in the main scanning direction;
- and
- fL represents a focal length of said at least one lens in the main scanning direction.
Dependencies are inferred from the claim text.