Abstract: A fiber optic connector having a double-clad specialty optical stub fiber with a deep index core-to-inner-cladding profile and a raised index outer-cladding profile. The double-clad optical stub fiber abuts against a single-clad field optical fiber of the single-mode type to form an interface across which the primary mode traverses without significantly interfering with higher-order modes. The ratio of the radius of the inner cladding to the radius of the core of the stub fiber is less than 6.5:1. The index profile of the refractive index of the inner cladding is deep relative to the refractive index of the core to confine the primary mode within the core. The raised refractive index of the outer-cladding pulls the higher-order modes deeper into that region, reducing interference with the primary mode. The respective core diameters of the field and stub fibers are matched to avoid mode-field diameter mismatch.

Abstract: A fiber optic connector having a double-clad specialty optical stub fiber with a deep index core-to-inner-cladding profile and a raised index outer-cladding profile. The double-clad optical stub fiber abuts against a single-clad field optical fiber of the single-mode type to form an interface across which the primary mode traverses without significantly interfering with higher-order modes. The ratio of the radius of the inner cladding to the radius of the core of the stub fiber is less than 6.5:1. The index profile of the refractive index of the inner cladding is deep relative to the refractive index of the core to confine the primary mode within the core. The raised refractive index of the outer-cladding pulls the higher-order modes deeper into that region, reducing interference with the primary mode. The respective core diameters of the field and stub fibers are matched to avoid mode-field diameter mismatch.

Abstract: A fiber optic connector having a double-clad specialty optical stub fiber with a deep index core-to-inner-cladding profile and a raised index outer-cladding profile. The double-clad optical stub fiber abuts against a single-clad field optical fiber of the single-mode type to form an interface across which the primary mode traverses without significantly interfering with higher-order modes. The ratio of the radius of the inner cladding to the radius of the core of the stub fiber is less than 6.5:1. The index profile of the refractive index of the inner cladding is deep relative to the refractive index of the core to confine the primary mode within the core. The raised refractive index of the outer-cladding pulls the higher-order modes deeper into that region, reducing interference with the primary mode. The respective core diameters of the field and stub fibers are matched to avoid mode-field diameter mismatch.

Abstract: A variable attenuator includes a rotatable actuator and cam arrangement arranged to vary a length of an air gap between ends of fibers in a transmission line. The cam arrangement includes a cylindrically shaped cam member having an end surface cut to fit a curve representing normalized attenuation-to-gap-length data, the cam follower(s) being fitted in a sliding member that holds the end of the optical fiber and moves it relative to a fixed end of another fiber connector member. The cam surface includes multiple identical cam surface sections extending less than 180° around the cam to define movement of the cam follower(s) and the sliding member between a maximum position and a minimum position.

Abstract: A spectral cover for a reflectance photometer is disclosed in which the spectral cover is designed to cover the readhead area of the reflectance photometer and block the transmission of light in a wavelength range of at least 60 to no more than 200 nanometers centered about the detection wavelength while permitting light of other wavelengths to be transmitted. The invention permits the readhead cover to be permanently or semipermanently positioned on the reflectance photometer. Since a user is able to see through the spectral cover it is possible to position a test device correctly and quickly over the readhead of the reflectance photometer. Signal noise levels due to ambient light are substantially eliminated by the invention.

Abstract: Simultaneous multiple photometer measurements are made by simultaneously passing light to be measured through multiple light paths to different locations of a circularly variable filter; passing the light through the circularly variable filter at said locations; collecting the light passed through the circularly variable filter at each location; transmitting the light passed through the circularly variable filter to separate detectors; and measuring the light transmitted along each light path by said detectors.

Abstract: Reflectance apparatus is disclosed for obtaining measurement of nonspecular reflected light in which controlled light rays are directed by means of a lens and transmission path from a light source through a light trap to expose or illuminate a specimen and nonspecular reflected light is passed from the specimen through the light trap along a transmission path to one or more detectors where the nonspecular reflected light is measured.

Abstract: In an apparatus in which particles which may include biological cells are passed through an optical sensing zone to measure their spatial radiant energy distribution for the purpose of identifying and/or characterizing the particles or cells, a structure and method are provided for increasing the usefulness of a geometric configuration of photovoltaic detectors such as a known assembly of generally concentric rings of such detectors usually including some wedge-shaped detectors. These are provided in a generally planar form and the invention provides structure which captures radiant energy in a flow cell of a particular type before projecting the energy to the detector. In particular an ellipsoid, paraboloid, hyperboloid or similar reflector which is symmetrical about its optical axis is utilized first to capture the radiant energy on angles which could include most forward and/or backward angles and all azimuthal angles and then deviating the same to the detector assembly mentioned.

Abstract: In an apparatus in which particles are passed through an optical sensing zone to measure their radiant energy distribution such as, for example, light scattering characteristics for the purpose of identifying the particles, means and a method are provided for deviating the collected light in accordance with predetermined different paths to a plurality of different photodetecting devices. The deviation is effected independently of collection by optical radiant energy transmitting or reflecting means. The different photodetecting devices enable the measurement of energy directed along the particular path which is identified with that device. The paths are established by the deviating means rather than permitted to evolve by the scattering phenomena themselves whereby the photodetecting devices can be located in convenient arrangements and may be conventional in construction.

Abstract: A particle analyzing apparatus comprising a reflector chamber containing an electrolyte and having a concave reflector surface with a first focus and a second focus; entraining structure, having an introduction tube for providing and moving a stream of particles suspended in an electrolyte solution through the first focus; a source of radiant energy for illuminating the particles as they pass through the first focus to produce a source of detectable radiation signals, which reflect off the concave reflector surface to be subsequently collected and analyzed; an exit tube coaxially aligned with the introduction tube; a sensing orifice mounted in the tip of the introduction tube or the exit tube; and a pair of energized electrodes disposed in the electrolyte solution on either side of the orifice, whereby the orifice creates a constricted electrical path in which the stream of particles generate electrical impedance signals as they move therethrough.

Abstract: An improved illuminating system for redistributing incident radiation, having a non-uniform intensity distribution, to resultant radiation, having a narrower desired intensity distribution in a predetermined region of an output plane, the illuminating system comprising a redirecting surface of a lens or reflector, for relocating at least a portion of the incident light. In one application, particles are illuminated in the output plane.

Abstract: In an apparatus in which particles are passed through an optical sensing zone to measure their light scattering characteristics for the purpose of identifying the particles, means and a method are provided for deviating the collected light in accordance with predetermined different paths to a plurality of different photodetecting devices. The deviation is effected simultaneously with collection by optical radiant energy reflecting means. The different photodetecting devices enable the measurement of energy scattered along the particular path which is identified with that device. The paths are established by the combined collecting and deviating means rather than permitted to evolve by the scattering phenomena themselves whereby the photodetecting devices can be located in convenient arrangements and may be conventional in construction.

Abstract: There is disclosed an illuminator and collector apparatus and method for fluorescence analysis wherein illumination of a stream of particles produces fluorescent light. A reflector, having a concave reflector surface with a first focus disposed in the stream of particles, has reflected therefrom organized illuminating radiation, such radiation converging upon the first focus to stimulate the particles into producing the fluorescent light. The fluorescent light emanates from the first focus, a portion of which is reflected from the concave reflector surface. This fluorescent light which is focused on the second focus contains no (or negligible) amount of illuminating radiation and is collected for subsequent detection and processing.

Abstract: Disclosed is a radiation collector apparatus and method primarily for counting and analyzing a flow of dilute particulate material, such as blood cells, sperm cells and the like, through the use of light detection. The radiation collector apparatus comprises a reflector chamber having an ellipsoidal reflector surface with a pair of elipsoidal foci defining a first focus, f.sub.11, and second focus, f.sub.12, and a second reflector surface with a primary focus, f.sub.21, positioned at the same point as focus f.sub.12, and a secondary focus, f.sub.22. The second reflector surface has the configuration of one of the conic sections of revolution. In operation the radiation collector apparatus is provided with an intensifed beam of light and a stream of particulate material aligned to intersect the intensifed beam of light at focus f.sub.11. Detectable light signals, after two reflections, are received in a focused beam by a photosensitive detector.

Abstract: Disclosed is a radiation collector apparatus and method primarily for counting and analyzing a flow of dilute particulate material, such as blood cells, sperm cells and the like, through the use of radiation detection. The radiation collector apparatus comprises a reflector chamber having an ellipsoidal reflector surface with a pair of ellipsoidal foci defining a primary focus and secondary focus. A window is formed in the ellipsoidal reflector surface and is centered on a symmetry axis defined by the primary and secondary foci. In operation the radiation collector apparatus is provided with an intensified beam of radiation and a stream of particulate material aligned to intersect the intensified beam of radiation at one of the ellipsoidal foci. Detectable radiation, either directly or after one or more reflections, proceeds through the window in an organized beam for detection.

Abstract: Disclosed is a radiation collector apparatus for analyzing particles by irradiating the particles to produce a source of detectable radiation, wherein the radiation collector apparatus comprises a reflector chamber having an ellipsoidal first reflector surface truncated in a plane of a minor axis of the same by a planar second reflector surface. Detectable radiation emanating from a primary focus of the first reflector surface either directly or after one or more reflections proceeds through a window formed in one of the reflector surfaces for subsequent processing. In another embodiment a dichroic second reflector surface is provided.

Abstract: A cuvette for containing a fluid to be analyzed by a single or multiple passage therethrough of a light beam whose rays are substantially parallel to each other. The cuvette is configured such that the substantially parallel light rays incident onto the cuvette remain substantially parallel after one or more passages of the light rays through the cuvette or the light rays have a minimum beam diameter at a selected distance from the cuvette. This is accomplished while the cuvette has a fluid holding configuration that minimizes contamination of subsequent sample placed therein.