JPS5742001A - Semispherical lens - Google Patents

Abstract

PURPOSE:To obtain an optical system of low aberrations, a small size and light weight by providing an another refractive index medium as a clad around a heterogeneous refractive index semisphere, and if necessary, providing a reflecting mirror, an optical modulator, etc. on the plane of the semispherical lens. CONSTITUTION:A spherical lens is formed of a spherical core 1 having heterogeneous refractive indices and a clad 2 having another refractive indices, and is parted by a cutting plane 3 passing the center thereof, whereby a semispherical lens is made. A mirror which reflects light is formed on a plane 3. The light which emits from an object point O and is ought to focus at an imagery point I' is reflected to focus at the point I (a). An optical modulator 4 of thin type is put closely together at the plane 3 of the semispherical lens to permit switching of whether the light out from the point O images at the point I' or at the point I by controlling the transmittance of light by the presence or absence of an electric signal (c). Thereby, the optical system of low aberrations, a small size and light weight is obtained.