Optical element
The present invention provides an optical element (or plastic molding) comprising an optically functional surface and a flange formed on the outer periphery thereof, and having on the flange outer peripheral surface a fitted portion inscribing on the inner peripheral surface of a lens-barrel and an adhering portion to be adhered to the lens-barrel by the adhesive filled in a concave groove of the lens-barrel, wherein a raised portion is formed on the flange surface inside the flange outer peripheral surface, whereby the adhesion area is enlarged, the adhesive capacity is increased, and a sufficient fitting area is secured, without the possibility of flow of the adhesive to the optically functional surface.
1. An optical element comprising:
a lens-barrel having an inner peripheral surface and an annular recess formed at an end of said inner peripheral surface having an annular recess inner surface extending axially;
an optically functional surface having a flange formed on the outer periphery thereof;
said flange having an outer peripheral cylindrical surface with a fitted portion fitted to the inner peripheral surface of said lens-barrel below said annular recess;
said flange having an adhering portion to be adhered to the lens-barrel which is an axially extending surface radially opposing said annular recess inner surface;
adhesive filled in said annular recess and on said adhering portion interconnecting said annular recess inner surface and said adhering portion; and
said flange having a raised annular portion extending axially and disposed radially inward of said adhering portion to prevent the adhesive from flowing to the optically functional surface.
2. The optical element according to claim 1 , wherein:
said raised annular portion has a first slant face on an outer peripheral side of said raised annular portion; and
said adhering portion is a second slant face extending from an upper end of said fitted portion.
3. The optical element according to claim 2 , wherein the first slant face and the second slant face are on the same plane.
4. The optical element according to claim 1 , wherein a space is formed between the raised annular portion and the optically functional surface.
5. The optical element according to claim 2 , further comprising an annulus contiguous with and between the first and the second slant surfaces.