Patent ID: 9720203
Date: 2017-08-01
CPC Classifications: G02B

Claim:
1. A lens unit comprising: a plurality of lenses; a lens holder which holds the plurality of the lenses; and a circular ring-shaped sealing member made of rubber; wherein a first lens of the plurality of lenses is disposed closest to an object side and is a plastic lens, the first lens being formed with a small diameter part and a large diameter part, the small diameter part having an outer diameter set to be smaller than the large diameter part and in a step shape on an image side of the first lens; wherein a sealing member accommodation part, which is a space in which the sealing member is disposed, is provided between an outer peripheral face of the small diameter part and an opposed face which is an inner peripheral face of the lens holder that faces the outer peripheral face of the small diameter part; wherein the sealing member accommodation part accommodates the sealing member so as to have clearance in an optical axis direction; and an inner face of the lens holder for defining the sealing member accommodation part is formed with a sealing member coming-off prevention part which is projected to the sealing member accommodation part to narrow the clearance on the image side of the sealing member accommodation part and thereby movement to the image side of the sealing member is restricted; an end face on the image side of the sealing member accommodation part is formed of an image side end face which is extended to an inner side in a radial direction from an inner side face of the sealing member coming-off prevention part; and wherein the sealing member coming-off prevention part is a protruded part which is formed so that a part including a face perpendicular to the image side end face is protruded to an inside of the sealing member accommodation part.