An optical mirror essentially consisting of a material containing silicon dioxide, for example, quartz glass, comprising a reflective plate, a carrier plate, and a supporting frame intermediate said plates and connecting them to each other and having a honeycomb structure consisting of a plurality of hexagonal cells, in which the supporting frame is composed of a plurality of Y-shaped elements and the outer longitudinal edges of the three wings of each of these elements are welded together with the corresponding edges of the wings of the adjacent elements so that each hexagonal cell is formed by two wings of each of three adjacent elements.
A reflective mirror structure comprising a concave uniform thickness honeycomb sandwich core and face plates. The sandwich carries a mirror base surface mounted on a ductile isolator material. The isolator material is characterized by its low coefficient of expansion, low thermal conductivity, and precision uniformity of support.
The subject invention provides a reflex camera having a specular reflecting surface within the optical path to the film plane. A novel light-weight but structurally stiff operator mechanism positions a viewing surface closely proximate the film plane for viewing-focusing purposes. In a subsequent exposure mode configuration, the operator mechanism positions a reflective surface within the optical path in a position causing a coincidence of a focal plane with the film plane. A film unit stored in the camera is covered by the operator mechanism during the viewing-focusing mode to prevent any illumination from reaching the film unit. When the shutter operates, the operator mechanism pivots about one end to uncover the film unit for an exposure by allowing illumination from a subject to reach the film unit.
A lightweight mirror is disclosed in which the core and backsheet of the mirror are constructed from a single piece of glass. The core is lightweighted by drilling or otherwise forming a series of pockets in the core with the machining process proceeding from the front of the core toward the backsheet. A plurality of walls left between each of the adjacent machined-out areas to provide the core with rigidity and to aid in supporting a facesheet on which a reflecting surface is formed. The facesheet is fastened to the rim of the core and to the walls which remain between the adjacent pockets in the core using a frit bonding process.
A reflectance modulator (10) includes a reflective plate (16) with a plurality of slots (18) forming a slot matrix of square portions (20). Side wall plates (22) are each slidingly received within a slot (18) forming a plurality of black body cavities (24) facing incoming radiation. Actuators (28) support the reflective plate (16) with respect to an object surface (12) and are energizable to modify the spacing of plate (16) from the surface (12) changing depth of the cavities (24) and reflectance of radiation.
A telescope mirror blank having a supporting network core composed of sintered ceramic struts, and a method of forming such core from a thermally crystallizable, powdered glass and as a separate component from the faceplate, are disclosed. Optionally, the mirror faceplate may be formed in a similar manner.
