Abstract: The present invention includes a system for monitoring surface structures on a planar surface utilizing a radiation source emitting a beam. The planar surface has various surface structure types, including a plurality of grooves therein which intersect at various angles which are equal to or less than a predetermined maximum angle. The system includes an apparatus for directing the beam to the planar surface along an optical axis perpendicular to the planar surface resulting in radiation being scattered from the planar surface and a reference beam being specularly reflected from the planar surface. The system also includes detector responsive to radiation scattered from the planar surface. This detector produces a first signal representative thereof.

Abstract: An image reader of the present invention is provided with a plurality of photosensitive elements arranged one-dimensionally or two-dimensionally substantially in parallel with an image bearing member, and first and second stopping plates each of which has apertures at positions corresponding to the photosensitive elements, respectively, between the image bearing member and the photosensitive elements. The apertures of the second stopping plate are smaller in size than photosensitive surfaces of the photosensitive elements. The dimension of the apertures, the dimension of the photosensitive surfaces of the photosensitive elements and the distances between the first stopping plate, the second stopping plate and the photosensitive elements are set in a predetermined relation. This prevents the influence of the deviation of a mounting position of the photosensitive elements on a measuring error.

Abstract: A vehicle light sensor for controlling light responsive systems such as an automatic headlamp dimmer. The sensor includes an enclosure containing a lens and a photo responsive detector. An optical chamber within the enclosure permits unwanted light from reaching the detector. A series of baffles within the chamber prevent light from outside a desired entrance angle from reaching the detector. A thin-film aperture is attached to the detector for controlling the size and shape of the detector's field of view. Gray scale shading may also be incorporated into the aperture to reduce the intensity of incoming light in selected portions of the field of view. An adjustment mechanism provides very fine angular view adjustments, beyond what is practical by simple assembly of molded parts.

Abstract: A directionally-sensitive flame detection apparatus and method for determining the presence of flame in a combustion chamber zone of a gas turbine. A radiation detector is coupled to the monitored combustion zone by a radiation collimator having mechanically-lowered internal reflectance so as to enhance the effective collimation angle. In this manner, a narrowed detector view angle is provided that is substantially independent of radiation wavelength or the material properties of the collimator tube.

Abstract: A novel composite imaging mask suitable for employment in a method for simultaneously determining coarse and fine petal piston in a segmented imaging assembly. The mask comprises a transparent substrate comprising two spaced-apart apertures, which apertures are dedicated to coarse petal alignment; a first overlay deposited on a face of the substrate, for defining four phase retardation regions dedicated to fine petal alignment; a second overlay comprising an opaque coating, the second overlay deposited on the face of the substrate and complementary to the four phase retardation regions and the apertures, and a means for spirally separating the coarse and fine alignment entities.

Abstract: A radiation detector, including, a photodiode, has improved uniformity of sensitivity over the field of view because the receiving surface is provided by an optical diffusing layer, and the field of view is defined by a baffle arrangement, each internal surface of whichy is reflective. The baffle arrangement also defines a volume and the diffusing layer conforms to a part of the volume adjacent to the apex thereof. The diffusing layer may be provided by material, initially in liquid form, solidified in situ within the baffle arrangement. The receiving surface may be provided within a receiving head of the detector, spaced from the photodiode. Radiation may be transmitted from the receiving surface, whether part of a separate receiving head or not, to the photodiode by an optical fibre. An assembly of four consituent detectors, each having three orthogonally arranged mirrors, may together define a hemispherically shaped volume.

Abstract: A device for measuring light scattered by an information support in which a light source is used to expose a portion of the information support. A sensor having a light-sensitive surface and an output signal dependent upon the quantity of light falling on such surface is positioned behind an objective lens disposed between the information support and the sensor. The exposed portion of the information support is smaller than the field of view of the sensor and the sensor is disposed at a distance behind the objective lens where the quantity of light on the light-sensitive surface of the sensor remains constant to within 5% in the event of a variation of .+-.20% in the distance of the information support from the objective. The light-sensitive surface of the sensor is disposed within the beam of light scattered by the information support and emerging from the objective lens.

Abstract: Disclosed is a solar radiation sensor apparatus. A light-blocking plate is provided above the light-receiving surface of a photoelectric element, and has an area smaller than the area of the light-receiving surface. The incident angle sensitivity characteristic of the sensor apparatus can be improved without involving any increase in the external dimensions of the sensor apparatus.

Abstract: A mask for reducing a semiperiodic variation of an output signal produced in response to a semiperiodic temporal variation of a distribution of radiation incident on the input of a detector. The mask can have a transmitance that changes abruptly at an outer profile of an opaque region or can have a varation in transmittance that varies continuously.

Abstract: An image reading method and apparatus includes detecting an optimal position of a slot of a light intercepting plate by reading an output level from a light sensor which receives light passing through the slit, moving the light intercepting plate to an optimal slit position in accordance with the read output level, and correcting any deviations in a scanning direction based on the amount the light intercepting plate is moved.

Abstract: A method and apparatus for measuring the velocity of a fluid in which a double-exposure image of the speckle pattern or particle images of tracer particle in a fluid is irradiated with a collimated beam of coherent light, and is subjected to Fourier transformation to produce Young's fringes at its focal plane. A slit is rotated relatively with respect to the double-exposure image to produce changes in the amount of light transmitted by the slit and determine the direction of the fringes. To determine the spacing of the fringes, a variable-spacing grating filter is used which is complementary to the image of the fringes and has a transmission distribution function of sin.sup.2 or cos.sup.2. The thus obtained direction and spacing of the fringes are used to determine the velocity of the fluid.

Abstract: A microdensitometer capable of submicron resolution is achieved by incorporation of adjustable diaphragms situated outside the optics of the microdensitometer.

Abstract: An electromagnetic wave shielding system for an optical sensor includes: a sensor body having an aperture through which an optical signal is made incident on the sensor body; a shielding plate disposed within the sensor body, the shielding plate having an opening having a dimension of at most about one-half of the wavelength of electromagnetic waves; an optical system for gathering the optical signal which passes through the aperture of the sensor body to the dimension of the opening in the shielding plate so that it can pass through the opening; and a detecting/processing unit for detecting and processing the optical signal which passes through the opening in the shielding plate. Thus, the electromagnetic waves which have entered are prevented from passing through or are remarkably attenuated by the opening in the shielding plate, and are thereby prevented from reaching the detecting/processing unit.

Abstract: An optical scanner device for producing machine-readable data representative of an image of a scan line object, comprising: a light source for illuminating the scan line object; a lens assembly for focusing imaging light received from the scan line object on an image plane; at least one mirror having a planar mirror surface for reflectively directing imaging light from the scan line object into the lens assembly whereby a folded imaging light path extending between the scan line object and the lens assembly is provided; and an occluding aperture stop positioned in immediately adjacent, overlying relationship with the mirror surface for selectively differentially blocking light in the light path emanating from different points across the scan line object for adjusting the light intensity of the image produced on the image plane whereby blocking of light with the occluding aperture stop at more than one location along the folded imaging light path is obviated.

Abstract: An optical information reading and writing device comprising a laser source which emits a laser beam for irradiating an optical recording disk to record an information therein and an optical signal detection system which receives a reflection beam reflected from the disk surface and controls position of the disk. The optical signal detection system comprises a condenser lens for converging the reflection beam and a dual grating element which has linear diffraction gratings formed on its both side surfaces. The incident side grating divides the reflection beam to two beams, one being a beam which is diffracted by the grating and the other being a beam which passes substantially straight through the grating without being diffracted thereby. The optical signal detection system further comprises a pair of three-segment light receiving detector elements for detecting the divided two beams. The two detector elements are disposed on a same plane.

Abstract: An optoelectronic pickup for providing an electrical output signal that is a linear representation of the relative displaced position of a mounted string. A collimated light source enables high contrast shadows of the string to be sensed by a photodetector. It also excludes information about the displaced position of the string in all directions except those along a single axis. The photodetector has a large flat surfaced area providing an output signal throughout the entire normal operating displacement range of the string. The design of the detector system results in a linear relationship between the relative position of the string and the total integrated illumination of the active area of the photodetector and hence the electrical output signal. A dual detector scheme allows the pickup to be immune to stray light and also to noise pickup on the lead wires.

Abstract: An incremental optical encoder comprising a luminous source 1, an encoder disk 4 having windows 5 and a sensor 3 with at least two photosensitive elements. The light intensity from the source may be varied by use of a U-shaped wire 8 having a branch 12 positioned between the luminous source at the photosensitive elements.

Abstract: An inspecting apparatus includes an illuminator, a light sensor positioned on one side of the path of movement of containers opposite to the illuminator capable of receiving rays of light which have passed through the container, rays of light reflected fro the container and rays of light travelling straight from the illuminator towards the light sensor within a predetermined region exteriorly of the container, a detector for analyzing the rays of light received by the light sensor, and a light absorbing or shielding member positioned diagonally and to the side of the container as viewed in a direction from the light sensor towards the illuminator. The light absorbing or shielding member shields rays of light reflecting from the surfaces of each of opposite wall portions of the container.

Abstract: A plurality of subaperture arrays which may be disposed within the diameter of the conventional single large aperture in order to achieve improved sidelobe energy characteristics with respect to that of the single large aperture. The apertures may be embodied as optical sources or radio frequency energy sources. The preferred arrangements of the subapertures include dispositions on concentric circles circumscribed within the single large aperture with a single aperture at the center of the large aperture and six, twelve, eighteen, twenty four and so on subapertures disposed on each subsequent concentric circle. One particularly attractive subaperture arrangement includes a total of nineteen subapertures with the outer concentric circle twelve of these subapertures being slightly rotated with respect to those of the inner concentric circles.

Abstract: A mathematical method for selecting the shape for an occluding aperture which is to be positioned at a predetermined aperture location in a light path extending between an illuminated line object and a linear photosensor array. Through use of the aperture selected according to the method, a light intensity measurement is obtained across the linear photosensor array which is uniformly proportional to the light intensity across the illuminated line object.

Abstract: The device permits a wide field of detection with high sensitivity and high locating precision. To this end, the device has a four-quadrant detector associated with a diaphragm formed by the central transparent zone of an opaque mask. The diaphragm preferably has a circular shape and no focusing lens. These elements are in parallel planes so that the line joining the centers of the diaphragm and the detector is perpendicular to these planes. The set is placed in a housing and is shielded by a transparent window. With a deviation measurement circuit that processes the detected signals, the assembly enables the computation of the angular offset of a pinpoint radiant source. With two elementary sensors of this type, it is possible to compute the spatial location of the source, for example a laser.

Abstract: An alarm system for military objects of a laser-radiating hostile weapon system. A plurality of units for detecting impinging laser radiation are mounted on an airplane, for example. Each detection unit is arranged to detect in one of six directions along three mutually perpendicular axes. The detection units are coupled to output signals representing the direction of incoming laser radiation to processing electronics. Each detection unit has an array of detector elements in a first plane and a diaphragm equal in size to the array in a second plane parallel to the first plane. The diaphragm and array are arranged so that the direction of the laser radiation can be determined from the pattern of detector elements activated in response to laser radiation passing through the diaphragm.

Abstract: The sensor comprises a radiation source (2), optical elements (5), a pattern generator (4), and a sensor field (3) which includes a plurality of distinguishable, measurable points. The pattern generator (4) changes the beam reflected from an object (8), imaging a pattern on the sensor field (3). An evaluator means (6) samples the individual distinguishable, measurable points of the sensor field and determines the measurement variable on that basis.

Abstract: A photodetector system for producing electrical signals responsive to the orientation of a light source, such as the sun, with respect thereto utilizes a diffuser to eliminate position-dependent sensitivities of the photocathode. The extent to which the diffuser or the photocathode itself is exposed to the incident radiation can be controlled by a shroud or by applying an absorptive coating in a predetermined pattern on an absorber cap, or on the diffuser directly. The shroud, by its configuration and its height above the photodetector, defines the range of angles of elevation and azimuth at which the diffuser can be illuminated. Such angles can also be controlled with printed or sprayed-on markings on the diffuser or absorber cover which form an opaque coating so as to prevent light transmission over predetermined regions. A fine dot pattern may be applied to the diffuser or the absorber cover, so that only partial transmission of the light can be achieved therethrough.

Abstract: Aligning a stable ring resonator by the use of an inversion mechanism ins the resonator and a pair of anti-symmetric masks. Each mask has opaque and clear parts and the masks are anti-symmetric in that, in use, one mask is positioned so that its opaque and clear parts are anti-symmetric to the opaque and clear parts of the other mask when it is in position. One mask is placed between the radiation source and the beam splitter while the other mask is placed between the beam splitter and the focal plane on which the two beam portions created by the beam splitter focus. One beam portion is directly reflected from the beam splitter and the other portion is transmitted into the resonator and is inverted while following a beam path within the resonator before being outcoupled through the beam splitter in a much weakened state.

Abstract: An alarm system for warning of a creosote chimney fire hazard, having both means to produce a visible alarm when the creosote temperature is nearing the creosote flash point, and means to produce an audible alarm when light from actual ignition of a creosote fire is detected. The invention also provides means to discriminate against detection of wood fire light, to minimize false alarms.

Abstract: An optical reading apparatus for a facsimile device in which a reading unit has a shading plate. The shading plate is arranged such that it can move in a direction inclined at angle .theta. (.theta.<90.degree.) to the light path of the reading apparatus.

Abstract: A reservoir fiber optic chemical sensor (FOCS) is formed of a modular cell body. A fiber optic is attached using a quick connect standard fiber optic connector. A semipermeable membrane is attached at the opposite end of the cell body using a quick attach membrane retainer. Multiple sensors can be made uniformly. Specific sensors for TCE vapor, O.sub.2 and CO.sub.2 are produced by utilizing a suitable reaction chemistry in the cell. A non-imaging optical focusing element can be included in the cell to increase sensitivity. A reaction cell can be placed adjacent to the reservoir cell with the semi-permeable membrane separating the two cells to produce a photolysis FOCS. TOC and TOCl can be detected with the photolysis FOCS.

Abstract: A micro pH sensor is constructed by reacting powdered aminoalkylated cellulose with a dye to covalently bond the dye to the aminoalkyl groups on the cellulose. Any excess unreacted aminoalkyl groups are blocked with a blocking agent and the dye containing powdered cellulose is taken up in a solvent. A portion of the solvated dye containing cellulose is deposited in association with an optical fiber. The cellulose is regenerated into a solid matrix by acid treatment of the solvated dye containing cellulose to deposit the dye containing celllulose matrix on the optical fiber.

Abstract: A part such as electronic parts is irradiated by diffused light and a silhouette of the parts is sensed by an image sensor, and plural optical systems are placed between the parts and the image sensor, and thereby the silhouette of the parts is divided into plural portions, moreover a shutter having plural openings is provided between the image sensor and the optical system to select one of the plural optical systems; thus one of respective silhouettes of the plural portions is sensed by the image sensor, and the portions are sensed in turn by shifting the shutter.

Abstract: A semiconductor light position detector for a rangefinder which projects a light beam onto an object and receives a reflected light beam from the object to measure a distance to the object. A portion of the light-receiving surface of the detector on which the reflected beam will not form a light spot is partially covered with a member that blocks unwanted light. Thus, the malfunctions caused by the flare component of the light from the light projector and the malfunctions due to increases in the shot noise under a high illuminance are reduced greatly.

Abstract: The invention presents means for protecting a remote sensing device such as missile seeker unit from damaging radiation outside of the sensing band of the detector and interrogating radiation attempting to determine the operating band of the sensor, its modulation rate, timing signal, or similar data which might be used to deteriorate the performance of the sensor.

Abstract: A reading surface of a document is illuminated by a light source, and a light beam reflected on the reading surface is reflected on a reflecting mirror. Then, the reflected light beam is guided in such a direction as to pass in the vicinity of a light shielding plate for shielding the constitutional elements from the light. A lens is located near the light source at a position where the light beam guided in the above direction is allowed to pass. A shading correcting device is made up of a first shading correcting portion formed by a part of the light shielding plate and a second shading correcting portion formed in a body case for holding the constitutional elements. The shading correcting device is designed to restrict a more quantity of light of the light beam incident upon the lens at a portion nearer to an optical axis of the lens. A photoelectric correcting device is provided in a position where the light beam passing through the lens is focused.

Abstract: An optical transmitting and receiving device for the contact-free reading of marks, particularly marks and bar codes. The device has a transmitter diode arranged in a plastic body which directs an oblique transmission beam onto a reference surface outside the plastic body. A receiver diode is arranged at an angle to the transmitter diode in the plastic body, whose receiver beam is likewise directed onto a reference surface. Instead of a glass optical system simple rectangular slotted diaphrams are provided and the transmitter and receiver beams intersect at one single point of intersection in the region of the reference surface.

Abstract: A two-dimensional linear motor is provided with sensors respectively capable of detecting only the x and y grid lines arranged in a platen traversed by the linear motor. These signals are accumulated and their counts are compared against the respective x and y distances the linear motor is to be moved in order to move the linear motor to the precise position desired and/or to verify that the desired movement has been accomplished. Differentiation of the mutually orthogonal sets of grid lines is accomplished by providing the grid lines with reflective surfaces which have different reflectivity characteristics or alternatively have a different reflectivity characteristics at with appropriate evaluation devices such as filters or threshold circuits which differentiate between either different wavelengths or different reflectivity characterisitics.

Abstract: Apparatus for determining the absolute position of a point on a surface or along a path including a tablet, scale, or overlay and a moveable mouse-type cursor. The tablet includes a unique pattern of lines or regions along rectilinear or other axes. A series of adjacent spaces formed by the lines define unique cells on the tablet. The mouse includes one or more linear imaging arrays adapted to detect the presence of tablet lines adjacent thereto. An integrated processor identifies the line types, computes line spacings and ratios, and identifies subtending cells by comparison to the known tablet topography. The processor further computes the precise location of a point defined on the mouse.

Abstract: A moire fringe displacement sensor includes first and second gratings (3) (4), a polychromatic light source (1) illuminating the gratings, and a detector (8). The gratings are disposed such that a relative displacement of the first and second gratings causes a variation in the color of the light reaching the detector. The detector (8) comprises first and second photo-responsive elements (11) (12), the responsivity with respect to wavelength of the first element (11) being different from that of the second (12). Signals from the photo-responsive elements are fed to a micro-processor (15) which calculates the color of the light incident on the detector as represented by two or more parameters on the Chromaticity (CIE) Diagram, and interprets the color in terms of the displacement of the first and second gratings.

Abstract: A scanning light beam is reflectively deflected by a light deflector in a main scanning direction substantially perpendicular to a subscanning direction in which an object surface to be scanned is moved. The deflected scanning light beam is passed through a scanning lens to scan the object surface in the main scanning direction. A synchronizing light beam is applied to the light deflector at a position where the scanning light beam is reflected thereby, in a direction allowing the synchronizing light beam that is reflectively deflected by the light deflector to be applied to the scanning lens. A converging lens is disposed on the optical path of the synchronizing light beam prior to application to the light deflector. The synchronizing light beam having left the scanning lens is passed through a grid and detected by a light detector assembly.

Abstract: An optical component is described which can be introduced into a finite or an infinite beam path and which is provided with a spectrally selective filtering characteristic and thus as the same time compensates the thereby generated geometric-optical negative influence by appropriate image-relevant compensation measures. The optical component exhibits at least one optically effective, non-planar surface. It has, for example, the property of completely absorbing visible light and of being completely transparent to shorter- or longer-wavelength light. In addition to this, a laser autofocus arrangement known per se is described, which is equipped with the optical component according to the invention, whereby a dark field illumination with an incident light microscope can be achieved while maintaining the autofocus function.

Abstract: A navigation device for wheeled vehicles using an optical locating system to determine the vehicle's position with respect to a set of coded, and therefore separately identifiable, fixed beacons. This optically obtained navigational information is used in conjunction with information from revolution counters on the vehicle's wheels to permit operation when one or no beacons are visible, and to refine the accuracy of the position determination as derived from the optical system alone.

Abstract: A projection type exposure apparatus for projecting an original pattern formed on a mask onto a substrate, which comprises a projection optical system, a lens tube member for holding the projection optical system, an alignment optical system and a battle wall member disposed along the path of the projection light beam in the space between the mask and the projection optical system for shutting the space from the flow of external air.

Abstract: A photodetector for use in an angular displacement measuring apparatus consists a multiple photocell consisting of radially extending strip-shaped photodiodes (11 to 15). According to the invention, the diodes are connected alternately via switching electrodes (7) to an output electrode (6), which is constituted by a conductive image-defining shield arranged above the switching electrodes and comprises two opposite bands (AB, CD), whose widths (b.sub.1, b.sub.2) are substantially inversely proportional to their radii of curvature in order to reduce trouble by cross-talk. The photodetector may be an integrated circuit, which comprises besides the multiple photocell also a part of the processing circuit. The invention also relates to an apparatus for measuring angular displacements by means of such a photodetector.

Abstract: A laser scanner apparatus using a laser reference beam that is directed to and scans a grating plate which is used for producing a data clock for the apparatus. The grating plate has a line grating formed by a plurality of lines that are equally spaced along the scan of the grating plate by the laser reference beam. The plurality of lines, if extended, intersect at a single point. The grating plate can have more than one such line grating.

Abstract: A photodiode assembly including a photodiode array having a linear arrangement of photodiodes, and a mask associated with the photodiode array to shade one or more selected photodiodes from incoming light of a particular frequency. The mask includes a frame provided with an elongated slot, and at least one bridge formed across the slot for shading the selected photodiode. The bridge portion is sufficiently wide to fully cover the selected photodiode and to partially cover the two adjacent photodiodes. An aperture is provided through the bridge in alignment with the selected photodiode to allow a portion of the incident light to impinge upon the selected photodiode.

Abstract: A confocal scanning laser microscope according to the present invention employs an aperture which is provided at a predetermined position within a plane of a photomask including rectilinear pattern edges orthogonal to each other formed on a transparent substrate. The aperture is moved in such a way that coordinate positions at which a laser beam traverses the respective rectilinear pattern edges orthogonal to each other are found using output signals from an optical detector, and it is consequently brought into agreement with a focused position of the laser beam.

Abstract: A picture reproduction apparatus for recording reproduced picture images of an original picture in which picture information on the original picture is projected onto a photoelectric converting element(s) such as a CCD line sensor(s) etc. through a focusing optical system, and according to an output signal therefrom unevenness of a light quantity of a light flux projected to the photoelectric converting element(s) is corrected to obtain a reproduction picture of uniform quality.

Abstract: A wavefront sensor for detecting distortion in light wavefronts is described in which the wavefront is divided into a plurality of subapertures and light amplified or intensified and imaged as spots of light from each subaperture onto a filter mask. The filter mask encodes a predetermined function of the spot intensity distributor onto the light intensity of the spot transmitted through the filter. For spot centroid calculation, the function is linearly variable. Mask embodiments include linearly varying alternate opaque and transparent chevrons, electronically variable chevrons, and quadratically varying chevrons.

Abstract: A focus control device comprises a light source; a recording medium on which light from the light source is focused; an objective lens for focusing light from the light source on the recording medium; a light receiving element for receiving the light reflected from the recording medium; an optical unit disposed in the optical path of the reflected light; and a beam splitter for separating the reflected light from an incident light path to the recording medium. The optical unit comprises absorbing parts adapted to absorb a part of the reflected light and transmitting parts adapted to transmit a part of said reflected light, and the absorbing parts forming a predetermined angle with respect to the optical axis of the reflected light.

Abstract: Apparatus for determining the absolute position of a point on a surface including a tablet or overlay and a moveable mouse-type cursor. The tablet includes a unique pattern of lines or regions along rectilinear or other axes. A series of adjacent spaces formed by the lines define unique cells on the tablet. The mouse includes a pair of linear imaging arrays adapted to detect the presence of tablet lines adjacent thereto. An integrated processor identifies the line types, computes line spacings and ratios, and identifies subtending cells by comparison to the known tablet topography. The processor further computes the precise location of a point defined on the mouse.

Abstract: A solar reference flight roll position sensor is mounted on a flight vehi having a longitudinal flight axis. The sensor, a photodetector, senses the angular position of the vehicle with respect to the sun about the flight axis. The sensor includes a lateral effect photodiode for generating first and second photocurrents in response to the position of a beam of sunlight illuminating the active surface of the photodetector. An opaque screen having an aperture is superimposed above the surface of the photodetector such that a different section of the surface is illuminated by sunlight passing through the aperture for different roll angles of the vehicle. The photocurrents are processed to form a discriminant that is a function of roll position. Roll rate is determined by measuring the rate of change of the roll position.