Abstract: An optical element includes: a glass substrate; an optical function portion made of a resin; and a bonding portion that bonds the glass substrate and the optical function portion to each other. The bonding portion has a glass transition point of 85° C. or lower. The glass transition point of the bonding portion may be 50° C. or lower.

Abstract: An optical element includes: a glass substrate; an optical function portion made of a resin; and a bonding portion that bonds the glass substrate and the optical function portion to each other. The bonding portion has a glass transition point of 85° C. or lower. The glass transition point of the bonding portion may be 50° C. or lower.

Abstract: To provide an antifouling film-coated substrate, which has a fluorinated organic silicon compound coating film and which is excellent in the antifouling properties as it has water repellency, oil repellency, etc. and also excellent in the abrasion resistance so that deterioration in the antifouling properties is prevented against repeated wiping operations. The antifouling film-coated substrate 3 comprises a transparent substrate 1 having a film-forming surface 1a exposed to at least a moisture-containing atmosphere, and a fluorinated organic silicon compound coating film 2 formed on the film-forming surface 1a of the transparent substrate 1 by a dry-mode method.

Abstract: To provide a low-cost wave plate that does not cause any diffracted light and wavefront aberrations. The challenge is met by providing a wave plate characterized by including a first region, a second region, and a third region which are placed on a glass substrate. The first region and the second region exhibit each uniaxial birefringence at least in their portions. The third region exhibits uniaxial birefringence and is interposed between the first region and the second region. Phase advance axes of birefringence of the first region and the second region are substantially parallel to each other. A phase advance axis of birefringence of the third region is substantially orthogonal to the phase advance axes of birefringence of the first and second regions.