Patent ID: 7864208

Claim:
An f-Î¸ lens usable with a light scanning unit to form an image on a photosensitive body, comprising: a lens part which has an incident side on which a deflected beam is incident, and an exiting side from which the entered deflected beam is exited; a joining part which has a joining side which is extended from the incident side and include an area to be formed with a light curable bond, and an emitting side which is extended from the exiting side and disposed to face the joining side, so that a light beam for curing the light curable bond is transmitted to the area of the joining side through the emitting side and the joining side; and an emitting part which is formed on the emitting side in a non-planar shape and provided to decrease loss of light quantity of the light beam scanned on the emitting side, wherein the emitting part comprises: a concave part formed from the emitting part toward the joining face; and a convex part having a convex portion formed inside the concave part to converge the entered beam onto the joining face.