Abstract: Making an optical prism of an enlarged ground and polished insoluble glass preform encased with soluble glass. The glass combination is heated and drawn to the reduced cross-sectional size desired of the prism with the soluble glass protecting the prism preform against deformation by surface tension forces and other damage. The soluble glass is removed after drawing to leave the prism body with true faces and angles.

Abstract: Apparatus for stabilizing the range of black to white level in a signal to a cathode ray tube, especially a signal produced by a detector in a charged particle microscope system. The stabilizing apparatus includes electronic circuitry for remembering the most negative (blackest) excursion of the signal for a predetermined time period, means for stabilizing all video input to that level and means for controlling the range of the signal (black to white) to remain within predetermined limits.

Abstract: An improved battery for use with an implantable heart pacer. An implantable heart pacer provides stimulation to the heart of a patient and is normally battery-powered. A primary reason for pacer failure and resulting pacer replacement is failure in the battery or batteries. The present invention provides improved insulation against leakage between positive and negative electrodes of the implanted battery thus extending battery life and pacer life.

Abstract: A scanning electron microprobe and display system adaptable to stereoscoptic or side-by-side viewing of an image for comparison on a television type monitor. The apparatus includes means for scanning the microprobe beam in a raster over a specimen and displaying the image on the cathode ray tube viewer. The microprobe beam scan is synchronized to the beam of the cathode ray tube and the cathode ray tube horizontal scan is blanked over a portion of its extent for sequential fields. For stereo viewing, the angle of incidence of the microprobe is varied in relation to the blanking sequence to provide side-by-side images on the cathode ray tube, each of which are generated from different microprobe incidence angles.

Abstract: Microscope objectives having a numerical aperture of substantially 0.25 and a magnification of about 10X provide a substantially flat image field of about 24mm.

Abstract: A leached fiberscope formed of a multiplicity of optical fibers each surrounded by a stray light absorber adjacent opposite ends of the fiberscope. This light absorber is formed by adding a light-absorbing constituent to leachable overcladdings initially provided on the optical fibers which are retained adjacent opposite ends of the fiberscope as the absorber and removed from intermediate portions of the length of the fiberscope to render it flexible.

Abstract: A patient stimulating pacer electrode for use with heart pacers or other like devices. The electrode is constructed in a porous manner to have large surface area to reduce polarization losses while simultaneously having small overall dimensions for increasing stimulation current density and its ability to stimulate. Electrically conductive powdered metal is subjected to a sintering process to produce a porous conductive structure which is employed as the electrode. Conductive fluid from within the patient's body flows into the interstices of the overall small-dimensioned porous conductive structure; the resulting fluid-structure interface comprises a large surface area thereby reducing polarization losses.

Abstract: Microchannel electron-multiplying plates formed of large numbers of glass-clad glass fibers all bundled tightly together in side-by-side relationship with each other and having their core sections removed for producing electron multiplying channels through the plates. Each channel has an electrically semi-conductive inner wall surrounded by an electrical insulating glass for preventing cross-talk of electrical energy between electron multiplying channels of the plates when the plates are in use.

Abstract: A method and apparatus for transferring frozen sections from a microtome or ultramicrotome to a microscope or the like without the deleterious effects of the ambient conditions. The apparatus includes a temperature regulated cooling means and protective enclosure to protect the frozen specimen during the transfer. The apparatus can be plugged into the vacuum chamber of an electron microscope and then the protective enclosure removed to present the frozen specimen for examination.

Abstract: An electron multiplier channel plate comprised of a web structure of open channels fused within a solid glass annulus. Inner walls of the channels are constructed of a high lead content glass having its electrical resistance lowered by treatment at high temperature in a reducing atmosphere. Outer walls of the channels are formed of a glass which remains rigid during the treatment at high temperature whereby the tendency for shrinking of the web structure along the inner boundary of the solid glass annulus is prevented.

Abstract: An electrical circuit for operating upon a slowly varying input signal (on the order of one volt per minute) to provide an output signal representative of the input signal derivative. The circuitry employs at least two feedback loops, one of which is constructed similar to an integrator amplifier. One particularly useful electro-medical application of this apparatus and method lies in the measurement of osmotic fragility of red blood cells, where percentage hemolysis of the blood slowly varies as a function of tonicity of suspension of the medium in which the blood sample is suspended. In this measurement the exact point of maximum slope is important and is provided by the present invention.

Abstract: A shortened image inverter formed of a plurality of light-conducting fibers arranged in side-by-side relationship with each other as a bundle having opposite image-receiving and image-emitting faces; the bundle being twisted intermediately of its opposite end faces by the amount of 180.degree. and compressed axially for shortening.

Abstract: The members which are utilized to hold and position a rod of erbium laser glass material within an imaging cavity are formed of a glass material which is transparent at the pumping wavelengths of the erbium ions and/or associated sensitizer ions in order to prevent masking of the laser rod to the pumping light energy at those locations where the holders come into contact with the laser rod. This arrangement optimizes the performance of the erbium glass laser rod configuration.

Abstract: A lens suitable for implantation in the eye is provided with a supporting system which accommodates to normal function of a dynamic pupil. The supporting system includes flexible spring-like members structurally designed to follow a dilating and contracting pupil while providing longitudinal fixation and centration of the lens.

Abstract: A high index of refraction, low softening point, low expansion segment glass is fused into a countersunk photochromic glass blank of lower index of refraction. The high index of refraction segment is primarily composed of SiO.sub.2, B.sub.2 O.sub.3, and PbO with lesser amounts of other oxides.

Abstract: A four element microscope objective has a predetermined magnification and a numerical aperture of substantially 0.10. The microscope objective provides correction for the usual chromatic aberrations as well as spherical aberrations, coma, astigmatism and a substantially flat image field over a 24mm field when used with a telescope objective as described in U.S. Pat. No. 3,355,234 and a typical 10.times. eyepiece.

Abstract: A high index of refraction, low softening point, low expansion segment glass is fused into a countersunk photochromic glass blank of lower index of refraction. The high index of refraction segment is primarily composed of SiO.sub.2, B.sub.2 O.sub.3 and PbO with lesser amounts of other oxides.

Abstract: A three element 12X eyepiece has an apparent field of view of about 51.3.degree. and a maximum exit pupil diameter of substantially 1.25mm.

Abstract: A process for preparing an abrasion resistant allyl diglycol carbonate lens is provided. The allyl diglycol carbonate lens prepared by the process of the invention has an abrasion resistant coating thereon comprised of a transparent base of a hydrolyzed polysilicic acid ester and polyvinyl alcohol comprising 90 to 100% hydrolyzed polyvinyl acetate.

Abstract: A lens suitable for implantation in the eye is provided with rearwardly disposed laterally extending iris clips anchored inwardly of the lens perimeter within openings extending forwardly into the lens from its rear surface.