Light scanning device and image forming apparatus

Abstract

The invention provides a light scanning device and an image forming apparatus. The light scanning device includes a first imaging lens, and a second imaging lens. The first imaging lens has a bottom surface adhesively secured to a housing via a plurality of adhesion portions. The second imaging lens has a bottom surface adhesively secured to a top surface of the first imaging lens via a plurality of adhesion portions. The plurality of the adhesion portions interposed between the first imaging lens and the housing are symmetrically located with respect to a center position of the first imaging lens in a main-scanning direction. The adhesion portions interposed between the first imaging lens and the second imaging lens are symmetrically located with respect to the center position of the first imaging lens in the main-scanning direction, and are located outside in the main-scanning direction with respect to the adhesion portions between the first imaging lens and the housing. According to the invention, the first lens is prevented from being deformed due to the different linear expansion coefficients of the first imaging lens and the housing when the environmental temperature changes.

Description

technical field [0001] The present invention relates to an optical scanning device and an image forming apparatus including the optical scanning device. Background technique [0002] Conventionally, there is known an optical scanning device in which imaging lenses are stacked in multiple stages on the bottom wall of a housing. This optical scanning device includes: a light source unit that emits a plurality of light beams; and a deflection unit that deflects and scans the plurality of light beams emitted from the light source unit along a main scanning direction. The plurality of light beams deflected and scanned by the deflection unit are imaged on the scanned surface through their corresponding imaging lenses. [0003] An example in which imaging lenses are stacked in two stages above and below is proposed. [0004] The two imaging lenses have the same shape, and three cylindrical protrusions are formed on the lower surface of each imaging lens. Adhesive portions made o...

AI Technical Summary

Problems solved by technology

[0005] In the existing optical scanning device, there is the following problem: when the ambient temperature changes, due to the difference in the linear expansion coefficient between the lower imaging lens (hereinafter referred to as the first imaging lens) and the frame, the first imaging lens produces bending

After the first imaging lens is bent, the optical performance of the first imaging lens decreases and the scanning accuracy of the beam on the scanned surface decreases.

Images