Scanning optical apparatus and image forming apparatus using the same
AssigneeCanon Kabushiki Kaisha
InventorKazumi Kimura
Life of this patent
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Abstract
A scanning optical apparatus includes incident optical system for causing at least one light beam emitted from a light source to be incident on a deflection device and image formation optical system including at least one refractive optical element and at least one diffraction optical element for imaging said at least one light beam reflected and deflected by the deflection device on a surface to be scanned. The diffraction optical element has at least one of an incident surface having a convex shape in a sub-scanning cross-section facing the deflection device and an exit surface having a convex shape in the sub-scanning cross-section facing the surface to be scanned.
Claims17
A scanning optical apparatus comprising:
- incident optical means for causing at least one light beam emitted from light source means to be incident on deflection means;
- and
- image formation means including at least one refractive optical element and at least one diffraction optical element for imaging said at least one light beam reflected and deflected by the deflection means on a surface to be scanned,
- wherein the diffraction optical element has at least one of an incident surface having a convex shape in a sub-scanning cross-section facing the deflection means and an exit surface having a convex shape in the sub-scanning cross-section facing the surface to be scanned.
A scanning optical apparatus comprising:
- incident optical means for causing at least one light beam emitted from light source means to be incident on deflection means;
- and
- image formation means including at least one refractive optical element and at least one diffraction optical element for imaging said at least one light beam reflected and deflected by the deflection means on a surface to be scanned,
- wherein the following condition is satisfied:
- 0.5<|e2/s1|<1.2
- where e2 represents a distance between an exit surface of the refractive optical element on an optical axis and an incident surface of the diffraction optical element on the optical axis, and
- s1 represents a distance between the incident surface of the diffraction optical element on the optical axis and a front focus position of the diffraction optical element in a sub-scanning cross-section.
Dependencies are inferred from the claim text.