Abstract: A photosensitive material is provided which comprises (i) a substrate comprising a crosslinked polymer having a transmittance of 90% or more in a wavelength region of from 400 to 700 nm and a refractive index of 1.55 or more, and (ii) a sensitive material layer provided on the substrate and mainly composed of a vinylcarbazole polymer. A hologram member employing the photosensitive material is also provided.

Abstract: A process for producing an optical element wherein an optical molding is formed by using a mold and thereafter released from the mold by supplying a gas to the boundary between the mold surface and the optical molding. In the process, no localized external force is applied to the optical molding during the release thereof, and therefore undesirable deformation or flaws of the optical molding are not caused.

Abstract: A hologram member and a method of preparing a volume type phase hologram film includes forming a volume type phase hologram in a polymer film formed on a substrate and comprised of a vinylcarbazole polymer, separating the polymer film from the substrate and allowing the hologram to be supported on the substrate so that the surface of the hologram not having contacted the substrate, contacts the substrate.

Abstract: A hologram member is provided which comprises a substrate, and a film in which a volume type phase hologram is recorded. The film is provided peelably on the substrate. The substrate preferably has a light transmittance of 30% or more at a wavelength of from 450 to 800 nm. The film may comprise a vinylcarbazole.

Abstract: An variable-focus optical device capable of changing the focal length with excellent responsiveness and reproducibility during repetitive deformation, comprises: an elastomeric member having prescribed viscoelastic characteristics, and an aperture member having an aperture adapted for causing projection or sinking of the elastomeric member therethrough or thereat.

Abstract: A method of preparing a volume type phase hologram film comprises forming a volume type phase hologram in a polymer film formed on a substrate and comprises of a polymer of vinylcarbazoles, and separating the polymer film from the substrate. Preferably, the polymer film is separated from the substrate in a liquid inert to the hologram.

Abstract: An optical device is composed by sandwiching a deformable member between sandwiching members. The deformable member has a shear modulus decreasing toward the inside. The deformable member may be a combination of a core and a coating with different shear moduli or a single body having a continuoudly decreasing shear modulus. The sandwiching members may be a flat plate either transparent or opaque or a lens with or without reflecting film. Because of inner soft and outer hard elastic nature of the deformable member, the sandwiching members can easily change their relative position to change an optical path and an imaging position of the optical device with good durability.

Abstract: A variable focus optical element comprises plural elastic members superposed in the axial direction and a deforming member having an aperture to cause the elastic member to protrude therefrom or descend therein thereby deforming the surface of the elastic members, and the modulus of elasticity of an elastic member at the protruding side is selected larger than that of another elastic member adjacent to first-mentioned elastic member at the protruding side.

Abstract: A variable-focus optical device comprises an elastomeric member having a gradient of shear modulus along its optical axis, and a deforming member having an aperture adapted for causing projection or sinking of the elastomeric member therethrough or thereat to deform the surface of the elastomeric member. The gradient of shear modulus is preferably one of continuously decreasing from the surface toward the inside of the elastomeric member. The gradient of shear modulus is provided by a concentration gradient of an inorganic substance such as silica dispersed in an elastomeric substance such as polysilioxane.