Abstract: A diode laser and optical system uses the minimum number of elements to obtain a small diameter beam (1 mm). A large numerical aperture lens collimates the full energy from the diode and the oval shaped output of the collimator is corrected for astigmatism by means of a cylinder lens and made circular by two identical prisms arranged to receive the corrected, collimated beam directly at a right angle surface of the first prism and transmit the beam after deflection to the second prism further which demagnifies the beam producing the round (.ltoreq.1 mm diameter) beam spot output of the laser. The output beam is well collimated (1 mRad) and wave front aberration is diffraction limited. The spot size at 50 feet distance is maintained. In order to hold total Gaussian distribution energy, the prisms are coated with a multilayer dielectric thin film eliminate reflection and to transmit the TE mode wave without loss at the Brewster angle.

Abstract: A general aspherical surface optical testing device comprised of a collimator lens system having lens designed to a predetermined radius of curvature that perfectly collimates a focused laser beam through an aberration compensating lens. The aberration compensating lens is designed to a predetermined radius of curvature to compensate for the aberration of an ellipse mirror, a parabola, or hyperbola mirror. A computer generated holographic general aspheric compensating plate is positioned between the collimator and the aberration compensating lens to make additional correction as needed in addition to the aberration compensations lens. For an aspheric mirror having a large numerical aperture, the hologram is order type.

Abstract: An apparatus and method are disclosed for characterizing the surface of mirrors in which a cross-grid type phase grating is illuminated from behind by light reflected from the mirror so as to create a grid-like interference pattern when observed along an observation axis. The fringe lines in the generated or observed interference pattern are correlated to the grating and observed for relative displacement from the grating axis. Apparent fringe index numbers for the fringe lines are used to determine coefficients for a plurality of monomial series which are in turn used to derive Zernike coefficients from which a wavefront contour is obtained. In order to reduce alignment errors during analysis, each fringe line is subtracted from the next lower order line and before monomial coefficients are determined.

Abstract: An apparatus and method are disclosed for increasing the alignment accuracy for off-axis mirrors in which a circular phase grating is illuminated from behind onto the mirror to be aligned creating a reflected image of the grating. The circular grating is aligned with the reflected image produced by the mirror so as to create at interference pattern when observed along an observation axis which is an approximate mirror optical axis. The generated or observed interference pattern is observed for the presence of moire lines and the mirror is translated or rotated about the observation axis until moire lines are minimized in, or disappear from, the observed interference pattern. The observation axis is then aligned with the optical axis of the mirror which can be recorded or marked. In further embodiments of the invention, the fringe pattern is transferred, using one or more lenses, to an image processing element such as a camera.

Abstract: A process for figuring the surface of a beryllium mirror to a predetermined urvature wherein the configuration of the mirror surface is sensed to locate areas of the mirror surfaces which are higher than desired and then a stream of phosphoric acid diluted with water and ethylene glycol is directed into contact with the areas of the mirror which are higher than desired while at the same time a current of 10 to 200 milliamps is passed through the stream to the mirror to electro-chemically polish the mirror surface.

Abstract: A computer assisted keratometer in which a fiducial line pattern reticle illuminated by CW or pulsed laser light is projected on a corneal surface through lenses, a prismoidal beamsplitter quarterwave plate, and objective optics. The reticle surface is curved as a conjugate of an ideal corneal curvature. The fiducial image reflected from the cornea undergoes a polarization shift through the quarterwave plate and beamsplitter whereby the projected and reflected beams are separated and directed orthogonally. The reflected beam fiducial pattern forms a moire pattern with a replica of the first recticle. This moire pattern contains transverse aberration due to differences in curvature between the cornea and the ideal corneal curvature. The moire pattern is analyzed in real time by computer which displays either the CW moire pattern or a pulsed mode analysis of the transverse aberration of the cornea under observation, in real time.

Abstract: A diode laser beam collimator is disclosed which is adapted to polarize and correct the characteristic oval shape of a diode laser beam to a circular shape. The preferred embodiment comprises a prism whose apex angle is selected in accordance with the beam intensity distribution to be corrected. A multilayer dielectric coating on one face of the prism polarizes the beam. The coating comprises alternating layers of low and high refraction index material, whose refractive indices are cooperatively selected with that of the prism material and apex angle.

Abstract: An improved plastic camera housing having an exterior decorative metallic coating and method of producing the same is disclosed. The camera housing assembly can comprise a polycarbonate glass fiber filled molded part that has been plasma etched in an inert argon gas filled pressure vessel. The camera part is plasma etched for a brief period of time to deteriorate the cross linkage of plastic bonding of the surface polymers without causing any outgassing of the elements of the plastic. A layer of copper is deposited to an approximate thickness of 1 to 3 microns in the inert subatmospheric environment. A second exterior layer of chromium approximately 0.2 to 0.5 microns is subsequently deposited to provide a hard abrasion resistant surface. Alternatively, a lacquer subsurface layer can be sprayed onto the camera part before the initial plasma etching.

Abstract: An erect optical imaging system for copying apparatus and method of producing the same is provided. A first pair of array sets of thick object lenses is optically aligned with a second pair of array sets of thick relay lenses to provide a scan line of a plurality of optical paths across an object surface. The refractive powers of the first set of lenses produce a real image in a space between the lens sets and an erect image on an image surface. Each array set comprises two parallel but offset rows of lens elements to provide an overlapping field angle. The use of the thick lenses helps eliminate vignetting problems. Spherical aberration and field curvature is controlled by minimizing the aperture opening of each set of lenses to 4mm.sup.2. The lenses can be made by either molding plastic or by individually grinding square glass bars. Demagnification can be achieved with the use of spherical optical path compensators.