Abstract: Variable focal power along one principal meridian may be obtained by an optical system having two cylinder lenses at either end and their axis of cylinder in a single plane spaced along an optical axis. A moveable cylinder lens with its axis oriented 90.degree. to the plane is slideably mounted therebetween. A plano color correction plate substantially eliminates color aberrations which would otherwise be present in the system.

Abstract: A relay lens system for use with a microscope to provide a station having a location optically equivalent to the back focal plane of the microscope objective is improved by using two identical lens components having different front and back focal lengths and arranged on the optical axis with opposite axial orientations. A back aperture viewer may be selectively positioned on the optical axis for viewing an optical element at said station.

Abstract: An ophthalmic glass lens having a compressively-stressed surface zone after ion exchanging which is at least 120 microns in depth, formed from an alkali metal oxide silicate glass comprising by weight about 4 to about 15 percent sodium oxide and about 3 to about 15 percent potassium oxide. There is a compressively-stressed surface layer having a strength of at least 25,000 psi. The total amount of sodium, potassium and other alkali metal oxides is up to about 20 percent. The total amount of zinc oxide, lanthanum oxide, magnesium oxide, and calcium oxide is about 8 to 15 percent, and there is about 3 to about 15 percent phosphorus pentoxide. An ion exchange process takes place at a temperature either above or below the strain point of conventional ophthalmic crown glass to produce satisfactory physical properties in the ophthalmic glass lens.

Abstract: Nondestructive marking of plastic artificial intraocular lenses for coding purposes. Exposure with ultraviolet radiation of portions of a lens surface forming boundaries of desired coding characters or similar exposure only of areas forming the characters themselves produces a differential in refractive index of the material of the lens wherewith detection and reading of the coding may be accomplished before and/or after intraocular implantation.

Abstract: A mold for forming lens blanks to meniscus shapes under applied heat and a force created by partial vacuum. A cupped lens shaping surface in the mold is cushioned and covered with a synthetic fabric for effecting exceptional accuracy in lens blank conformance to shaping surface curvature, optimum surface smoothness and quick release upon completion of a forming cycle.

Abstract: Ophthalmic lenses formed of ophthalmic glass and having accurately finished front and back curved surfaces and edged to the shapes desired are heated in molten salt bath and ion-exchange hardened on all surfaces thereof so as to satisfy high safety standards while being substantially free from optical image distortions for objects viewed therethrough. The invention includes method and apparatus for rapid and controlled pre-heating, soaking and cooling steps of lenses relatively cheaply and in sizable numbers at the same time.

Abstract: The invention achieves local variation, or a continuous gradation, in photochromic or phototropic properties across the face of glass lenses and lens blanks, especially those of ophthalmic quality. The lenses and lens blanks contain all those ingredients required to produce photochromic or phototropic behavior. They are exposed to a locally variable temperature field or environment, in such manner as to, in at least one portion of the lens or lens blank cause the temperature therein to exceed the strain point but not the softening point of the glass. In other portions of the lens or lens blank the temperature is below the strain point, thus causing development of phototropic or photochromic behavior only in those portions of the lens or lens blank exposed to the temperatures above the strain point.

Abstract: A centrifugal casting mold and mold clamping system adaptable to mass-production technology including a tapered multiple part mold and similarly tapered sleeve within which the assembled mold is insertable for resin filling and centrifuging.

Abstract: A laminated optical or ophthalmic element is produced comprised of an amorphous and/or crystalline material possessing phototropic or photochromic properties as a result of applying a thin layer over at least one surface thereof, which layer includes a combination of cations and anions including silver or copper bromide and/or chloride.

Abstract: A microscope illumination system provides light for both transmitted and vertical microscopy techniques. A transmitted light illuminator comprises a collector lens system, a zoom lens system, and a collimator lens system which direct the light from a source to the microscope condenser. The vertical illumination system utilizes the same light source and comprises a collimator lens system, a relay lens system, and a collector lens system which provides the light directed into the rear of the microscope objective by a beam splitter.

Abstract: An electron multiplier channel structure having channel walls formed of alternate strips of different glasses. One glass has optimum electrical conductivity properties and the other glass has optimum secondary electron-emitting properties. The strips are contiguous so that electrical conducting strips can readily supply electrons to neighboring electron emitting strips when an electrical potential is applied across the multi-channel structure.

Abstract: Making perforate optical sections (lenses) of pseudophakoi with avoidance of drilling operations and adversities thereof. Lens material is drawn with embedded acid soluble columns corresponding in diametral size and relative juxtaposition to the size and spaced locations of holes needed in a lens and the columns are etched away prior to or following final edging and surface finishing of the lens. Making multiple lens preforms is contemplated.

Abstract: An alternating light photometer, the output of which is connected over two parallel uniform current paths with both of the inputs to a differential amplifier. In each of the paths, there is included in series a resistance, a condenser, with a switch provided as well as between a switch and corresponding input of the differential amplifier, and an operational amplifier, all forming a storage circuit. The R C circuit forms a low pass with a time constant over the given engaging or disengaging time of the beam. The switches are so controlled over the switching circuit that only one of them is closed during the time of the complete release, and the other only during the time of the complete interruption of the beam to the photoelectric transducer.

Abstract: A vertical illuminator for imaging a light source at the back aperture of a microscope objective for use in fluorescent microscopy has a light source, an axially-movable positive meniscus lens which has an aspheric convex surface, a positive biconvex lens, and a negative meniscus lens all in sequence and aligned along an optical axis with a beam splitter for introducing light from the source into a microscope observation system. The movable meniscus lens is used to focus an image of the light source at the objective back aperture.

Abstract: Optical sections (lenses) of pseudophakoi having tangential holes are produced without drilling operations. A preform of lens material is drawn with embedded acid soluble rods and/or openings corresponding in diametral size and relative juxtaposition to the size, shape and locations of holes needed in a lens, a lens blank is cut from the drawn preform and portions of rods remaining therein are etched away prior to or following final edging and surface finishing of the lens blank.

Abstract: A pair of spectacles having a lightweight frame structure especially designed with unusual pantoscopic tilt in combination with rocking-pad nasal support affording minimal facial contact and cable temple ends adapted to intimately engage and extend about a large portion of the ear for sureness of continued proper fit of the spectacles upon the face during pursuance of the sport of tennis.

Abstract: There is provided by the process of the invention a silicate glass which provides protection against mechanical hazards and short and long wavelength ultraviolet radiation while at the same time high transmission of light in the visible range of the spectrum is maintained. By the process of the invention, the incorporation of cerium oxide into the glass followed by ion exchange strengthening using a mixture of potassium salt and silver nitrate provide a synergistic reduction in transmission of light in the ultraviolet range of the spectrum not heretofore obtainable by the use of either cerium oxide or silver staining of the glass alone.

Abstract: A field emission gun in which a field emission tip for generating charged particles is axially aligned with apertures in an intermediate electrode and a main electrode. A field electrode is placed in juxtaposition to the field emission tip for developing a particle generation field. This electrode is located relative to the field emission tip and the intermediate electrode to effect a predetermined focal distance and level of electron beam intensity. Use of a field electrode permits utilization of lower focusing and acceleration voltages and renders the device less sensitive to variations in field emission tip design and performance.

Abstract: A mold for casting contact lenses from an unpolymerized resin such as silicone gum wherein the resin is polymerized by high energy radiation such as an electron beam. One part of the mold is a cap capable of transmitting such radiation. The male section of the mold is gold plated to minimize reaction between the resin and the male section under the influence of the electron beam.

Abstract: A two-element eyepiece having a biconvex singlet with the radii of the convex surfaces being substantially identical and a convex-plano doublet formed of a biconvex element having radii of the convex surfaces being substantially equal with a concavo-plano component cemented thereto, has a field of view of approximately 40.degree. with good correction for normal eyepiece aberrations. Eye relief is approximately 80 percent of the effective focal length.