Abstract: An optical component having a gradient refractive index produced by multiple windings of a glass fiber over a glass mandrel. The fiber is provided with a refractive index gradation which varies from an approximate match with the mandrel to selected lower values along its length thereby causing refractive index in the depth of windings to vary accordingly. Fusion and drawing of the mandrel and windings provide a rod (or fiber) of solid cross-section having a radial index gradient of predetermined profile.

Abstract: A multi-lumen fluid-tight catheter having optimum resistance to bending and method of manufacture. The catheter is notched about its periphery and along its length to create voids which are filled with a vulcanized polymeric material.

Abstract: In a microscope, a nosepiece support assembly and a coarse and fine adjustment mechanism in direct operative control of the support assembly, the support assembly including a nosepiece mounting carriage with a depending rod rigid therewith and mounting a cam follower which rides on the edge of a cam, rotation of which is controlled by the adjustment mechanism. The adjustment mechanism in turn includes a reduction gear assembly utilizing dual gear trains and mounted to a cam-mounting shaft externally of the frame of the microscope and housed within a coarse adjustment handwheel for immediate access thereto. One of the gear trains incorporates a compound gear having a torsion spring between the individual gears to enhance gear train interengagement throughout the gear assembly.

Abstract: A valve body (20) for an endoscope is moulded from polypropylene and has a straight through bore (27) to aid cleaning of the valve body. The valve body (20) has spaced external ribs (48, 50) which locate the valve body (20) with respect to the casing of a handle (10) of the endoscope. At one end the valve body (20) receives a threaded sleeve (30) which retains a slidable valve member (34) in position, a cap (42) being manually depressed against spring loading to open the valve and place a source of suction in communication with a side stem (38) which is intended to be connected to a passageway leading to the distal end of the endoscope shaft.

Abstract: A current to frequency converter comprising a current source, for example a photocell, a voltage to frequency converter, an integrator in the feedback loop of the converter, the current source being connected to the summing junction of the converter and integrator such that the frequency of output pulses from the converter is directly proportional to the magnitude of current injected from the converter to the summing junction, and a controlled circuit for attenuating the current injected from the converter to the summing junction to increase the frequency of output pulses. The controlled attenuating circuit includes a transistor switching arrangement for introducing increased resistance in the path for current injected from the converter to the summing junction in response to the presence of a control signal.

Abstract: An endoscope has a shaft (4) detachably connected to a handle (2) to enable the shaft (4) to be detached for repair or maintenance. The shaft (4) and handle (2) are detachably connected by spring-loaded latches (10) in the handle which are frictionally engageable with pins (8) projecting from the coupling face of the shaft (4). An external locking sleeve (20) prevents inadvertent separation of the shaft and handle. Illuminating light and the image to be viewed are coupled across the handle/shaft interface by abutting ends of fiber optic bundles (76, 80, 86, 92). The shaft (4) can be flexed by adjustment of manual controls on the handle as a result of racks (40, 44) in the handle (2) exerting a pushing motion on racks (50, 52) in the shaft (4), this pushing motion being transmitted into a pulling action applied to flexure wires (66, 62) extending in the shaft by virtue of pinions (54, 56) interconnecting the two racks of each pair of racks (50, 52) in the shaft (4). An alternative embodiment (FIGS.

Abstract: An exposure and camera control system comprising a keyboard for providing input information relating to film parameters and camera type, a light to frequency converter for providing signals having a frequency proportional to the intensity of light to be used in exposing the film, and a control operatively connected to the information providing keyboard and to the light to frequency converter for determining the film exposure time and for providing signals for controlling film exposure to light and signals for controlling film transport when the exposure is complete. The control includes a microprocessor, programmable memory, and input/output interface components. A display operatively connected to the control provides visual display of information inputs to the control and of calculated quantitites such as exposure time. A printer operatively connected to the control provides a hard copy record of the displayed information.

Abstract: A circuit for operating and controlling optical apparatus for viewing an object and making a photographic record thereof and having an illuminating light source and a photoflash light source, the circuit including a pulse width modulator for operating the illuminating light source, a flyback converter circuit and capacitor charging and discharging circuit for operating the photoflash light source, a clock pulse source connected to the pulse width modulator and the flyback converter for operating the same, and a delay circuit for allowing the optics to settle before operation of the photoflash. An energy level control circuit monitors the capacitor voltage and stops application of clock pulses to the flyback converter when the capacitor voltage reaches a desired value. A first visual indicator signals when the desired capacitor voltage is reached, a second visual indicator signals a certain condition in the apparatus, and a circuit gives priority to operation of the second indicator.

Abstract: A four-component microscope objective has a numerical aperture of 0.66. When used with a telescope objective as described in U.S. Pat. No. 3,355,234, the objective provides a magnification of 40X and is well corrected for the usual chromatic image aberrations, spherical aberration, coma and astigmatism.

Abstract: A glass faceplate having a central area of required useful diameter surrounded by a narrow ring of opaque glass and an outer glass mounting flange. Light entering the flange or ring is prevented from reaching the central area as stray light or glare in the system and spurious reflections at the interface of the ring and central area are minimized by a refractive index match of the two innermost glasses.

Abstract: A refractor optical system having a new series of spherical and cylinder lenses substantially eliminates the irregular occurrence of additive errors when lenses spaced from the reference plane are used or more than two lenses are combined and permits correction for the significant additive errors by non-additive lens selection is disclosed.

Abstract: A glass faceplate having a central area of required useful diameter surrounded by a narrow ring of opaque glass and an outer glass mounting flange. Light entering the flange or ring is prevented from reaching the central area as stray light or glare in the system and spurious reflections at the interface of the ring and central area are minimized by a refractive index match of the two innermost glasses.

Abstract: A flexible image-conducting bundle of optical fibers is produced by juxtapositioning and drawing a multiplicity of glass-clad glass fiber preforms and interstitial rods of leachable glass. The drawn assembly is cut to desired length and interstitial glasses are leached from the intermediate portion of the cut piece.

Abstract: A tonometer with an improved objective unit containing a fluid discharge tube having a portion thereof extending into a plenum chamber enhances the consistency of repeated regulated air discharges. The consistency is further enhanced by texturizing the inner wall of the discharge tube. Since the discharge tube extends into the plenum chamber, the objective unit can have substantial interchangeability with other tonometers.

Abstract: A five-component 40x microscope objective having a plano-convex positive doublet as the third element providing sufficient color correction to permit classification as a semi-apochromatic objective is disclosed.

Abstract: A fiberscope objective having an oscillating lens element which causes images formed by the objective to scan across a receiving end of an image-transporting fiber bundle for increased image resolution and bundle blemish suppression. Synchronous scanning of the opposite bundle end renders transported images stationary for viewing.