To miniaturize a lens and to appropriately position it into an attaching holder by providing a 1st positioning surface extended from the periphery of a lens effective surface in an orthogonal direction to the optical axis of the lens effective surface and a 2nd positioning surface extended in the orthogonal direction to the 1st positioning surface.

The 1st positioning surface 18 extended from the peripheral edge of either effective lens surface 16 of the lens main body part 12 of the plastic molded lens 10 in the orthogonal direction to the optical axis (t) of the surface 16 of the main body part 12 is formed at an annular part 14 integrally formed on the outer peripheral surface of the main body part 12. The outer peripheral surface, that is, the cylindrical surface of the annular part 14 forms the 2nd positioning surface 20. The surface 20 is extended in the orthogonal direction to the surface 18 and takes the optical axis (t) of the main body part 12 as a center axial line. When the lens 10 is attached to the attaching holder 30, the 1st and the 2nd positioning surfaces 18 and 20 are butted against the 1st and the 2nd positioning surfaces 36 and 38 of the holder 30.