Abstract:
A polygonal shaped, multi-faceted rotary scanner comprising a plurality of optically flat, reflective surfaces on facets (5 to 12) are integrally bonded to a multi-faceted, polygonal base (4, Figure 2) at precise angles to the axis of rotation by a replication technique in which each optically flat reflective surface is produced on the surface of a flat master preform and the flat master preform is accurately located in position at the precise angle by contact with an upper and a lower facet of a master multi-faceted polygonal fixture and the flat reflective surface is adhesively bonded to the corresponding facet of the polygonal base (4), said polygonal base (4) being assembled concentrically between the upper and lower facets of the fixture prior to application of a small quantity of a liquid adhesive to the surface of the facets (5 to 12) of the polygonal base, which adhesive on hardening, adhesively bonds the reflective layers of the or each master preform to the appropriate facets of the polygonal base (4).
Abstract:
A high reflectance mirror (30) utilizing a dielectric stack (32) having multiple layers of low (2,4,6...32L) and high (1,3,7...33H) refractive index material at least one of which is absorbing atthe design wavelength. At least one pair of layers is formed on a substructure (31) with the thickness of the individual layers being both different from a quarterwave optical thickness and preselected to maximize the reflectance of the mirror. Mirrors in which both dielectric materials in the stack have different absorptances at the design wavelength are disclosed with the layer thicknesses of one or more optimum pairs formed on a substructure being different from a quarterwave optical thickness such that the layers of higher absorptance material are less than a quarterwave optical thickness and the layers of lower absorptance material are more than a quarterwave optical thickness. The individual thicknesses of the layers are optimized to provide maximum reflectance, leading to a nonperiodic stack when a substantial number of such optimum pairs of layers are utilized.
Abstract:
A low-cost, dual-view, immersible periscope (10) that is particularly suitable for use as a toy or learning tool in environments such as bath tubs, sinks, tidal pools, outdoor wadding pools, or other aquatic areas where children play and explore. The periscope has an upper viewing compartment (46) that operates in air and a lower compartment (50) that floods with water as the periscope is immersed and contains the entrance aperture. The upper and lower compartments are separated from one another with a transparent window (52), which the upper compartment surrounds isolate its air space from surrounding water to provide a completely still image of activity taking place beneath the surface even though it may be turbulent with wave action. Additional enhancements include magnification, underwater accessory lighting, sound effects, torpedo tubes, and means for placing transparencies over the entrance aperture to integrate images with underwater action.
Abstract:
A ceramic mirror having a surface flatness of less than 1 νm and/or a centerline average roughness of less than 1 nm measured by a laser interference method. A method of manufacturing ceramic mirrors, comprising the steps of forming titanium oxide powder having an average grain size of less than 1 νm and a purity of more than 99 %, and thereafter sintering the powder in the atmospheric air, an inert atmosphere, a vacuum atmosphere or a reducing atmosphere at a temperature of 1000-1300 °C.
Abstract:
For use, e.g., in the compensation of frequency dispersion in the course of transmission of an optical signal, a pulse-shaping device is provided with a suitably shaped nonplanar mirror (16). When spatially spread-out frequency components -- produced, e.g., by a grating (14) -- are reflected from such mirror, a frequency-dependent phase shift is introduced; for example, such phase shift may be a third-order function of frequency. Upon recombination of frequencies, a shaped pulse is obtained. Furthermore, third-order compensation can be used to compress amplified light pulses, e.g. as produced by a semiconductor gain medium (80, 81).
Abstract:
An apparatus is provided for magnifying the image of distant objects which has the unique feature that objects to be viewed can be at any arbitrarily large distance from the apparatus. In addition, the apparatus does not require positioning of the eye at the exit pupil of the instrument; it does not require centering of the eye on the optic axis of the instrument; and it does not require refocusing for different object distances. Still, it provides erect, non-inverted images to the viewer. The invention includes a positive optical element (53) defining an optic axis for the apparatus and having a positive focal length for converging an incoming bundle of rays of electromagnetic radiation. Also included is a negative optical element (51) aligned with the optic axis and separated from said positive optical element by a distance d1, with the negative optical means having a negative focal length that is substantially equal in magnitude to the focal length of the positive optical means and having a focal point on the optic axis.
Abstract:
A mirror (10) having optical quality reflective faces (14) is prepared by pressing of metallurgical powders. An optical quality surface (14), free of scratches and irregularities, is formed by pressing the faces with an optical quality tool face (44), applied to the face at an acute angle to achieve a degree of metal flow. The mirror (10) is progressively formed, by first pressing an assembly of powder to a ''green'' powder mirror, sintering the pressed powder, and then repressing the sintered mirror using a tool having optical quality surfaces on the faces contacting the mirror faces. The mirror is annealed, repressed with the tool having optical quality surfaces, and coated on the reflective surfaces with a thin metallic coating. This technique is particularly effective for preparing large numbers of mirrors with multiple facets requiring precise facet intersections, as the pressing tool can be adjusted to produce highly exact facet intersections which are then reproduced exactly in subsequent mirrors.
Abstract:
A lightweight mirror comprises a silicon carbide (SiC) foam core having a bulk density of approximately five percent. The mirror further comprises two solid facesheets each of which is integrally formed upon a surface of the SiC foam core, the facesheets being comprised of SiC. Upon a machined surface of one or both of the facesheets a further layer of SiC is deposited to reinforce the SiC facesheet and to provide an optically polishable surface. This outer layer of SiC may be deposited by chemical vapor deposition (CVD) techniques. After depositing this reinforcing layer of SiC, the layer is machined and polished to provide a mirror surface having a desired flatness and optical quality.
Abstract:
A reflector apparatus (10) having a reflective layer (24) enclosed within a sealed envelope (16) having a lower light absorptive sheet (20) and an upper light transmitting sheet (22).
Abstract:
An optical system for viewing the rear seat area of a vehicle through a rearview mirror (15) and a roof mounted forward facing mirror (22) is provided. The forward facing mirror is mounted with the headliner (24) in a fixed or adjustable manner and there is a friction hinge for moving the mirror from a substantially flush position with the headliner to an extended position projecting from the headliner. Lights (29, 30) can be provided with the mirror to enhance the image of the rear seat. The mirror system in the rear of the vehicle can be multi-purpose. It can act as a forward facing mirror, alternatively it can swivel to act as a sun visor to a side window, or alternatively the reverse side of a double mirror system can be used as a vanity mirror with illumination as required.