Patent ID: 9377621
Filing Date: 2016-06-28
CPC Classification: B41J,G02B,G03G

Claim Text:
1. A light scanning apparatus, comprising: a deflection element including a first deflection surface for deflecting a light beam from a first light source and a second deflection surface for deflecting a light beam from a second light source; a rotor including a top surface facing the deflection element, the rotor being configured to rotatably hold the deflection element; a first imaging optical system including a first imaging lens, the first imaging optical system being configured to guide a light beam from the first deflection surface to a first scanned surface; a second imaging optical system including a second imaging lens arranged to face the first imaging lens so as to sandwich the deflection element, the second imaging optical system being configured to guide a light beam from the second deflection surface to a second scanned surface; a first shielding member arranged in an optical path of the first imaging optical system; and a second shielding member arranged in an optical path of the second imaging optical system, wherein the following conditional expression is satisfied: where A represents a distance from a reference plane to an edge portion of the first shielding member in a sub-scanning direction on a side closer to the top surface, the reference plane including a center of the first deflection surface in the sub-scanning direction and being parallel to a main scanning cross-section, H represents a distance from the reference plane to the top surface, L represents a distance from a deflection point of the light beam at the first deflection surface to the first imaging lens, P represents a distance from an axis of rotation of the deflection element to the first imaging lens, S represents a distance from the axis of rotation to the first shielding member, D represents a diameter of the top surface, and p represents an angle of incidence of the light beam from the first light source with respect to the first deflection surface in a sub-scanning cross-section.