Abstract: The spatial field is sequentially convolved at each of a plurality of uniformly-spaced intervals along a field dimension with a given type of limited spatial extent kernel function which preferably has a one-octave spatial bandwidth. Convolution combining means derives an output only if the q'th power of the sequential convolutions exceed a threshold corresponding to the just-noticeable presence of spatial frequencies within the spatial bandwidth of the kernel function.

Abstract: This apparatus comprises a device for illuminating in a permanent manner a zone in which the band travels, a television camera having a high luminous sensitivity and a low remanence controlled for exposure during constant periods of time which are short relative to the speed of travel of the band with a frequency of recurrence which is substantially equal to the speed of the band divided by the length of said zone in the direction of travel of the band. In this way, said successive images detected constitute a substantially continuous representation of the band. An electronic circuit is provided for analysing the images received by the camera.

Abstract: A blackening sensor analyses a signal generated by the detection of scattered light reflected from a succession of small illuminated areas on the surface of a web to determine the degree of skewness of the amplitude distribution of the generated signal from a normal distribution, thereby to provide an indication of the degree of blackening.

Abstract: The invention relates to a method for detecting continuously the direction of the weft threads in a moving woven material. A plurality of unit slits (at least three), hereinafter referred to as a "divided slit arrangement," is provided, the plurality of unit slits having a pitch substantially the same as that of the weft threads. The divided slit arrangement is disposed adjacent to the woven material which moves traversely between a light source and at least three unit weft thread detectors. Each detector comprises an alignment slit and a transducer, and is designed so that a moire (generated by light passing through the divided slit arrangement and the weft threads of the woven material), as transmitted through a condensing lens and the alignment slit to the transducer, is converted to an electric signal.

Abstract: An automatic on-line computer-aided inspection system for a running web utilizing a transverse web scanning means, detection means incorporating feature extraction and processing circuitry for generating unique output signals corresponding to said web scanning characteristic of web features of inspection interest, means converting the output signals to digital data words input sequentially to a digital computer, said computer applying one or more algorithms to said words, thereby calibrating the values of said features of said words, comparing said calibrated feature values to at least one set of product-qualifying values held in memory, and means responsive to the computer classifying the web as acceptable or non-acceptable as regards areas of preselected marketable size in the web.

Abstract: Optical monitoring apparatus for detecting the angles at which light rays leave a material surface scanned by a light bead such as an incident laser beam includes a row of individual Fresnel lenses arranged edgewise directly adjacent each other to focus light leaving the surface onto respective arrays of photodetectors arranged in their focal planes.The outputs from the photodetectors are connected together by processing means to allow evaluation of their output signals. The row of Fresnel lenses may also be used for other optical monitoring purposes.

Abstract: Device and method for the optical inspection of speck-like and streaklike defects in a moving web.A source of radiation illuminates a transverse zone of the web, a series of photocells measures the radiation after transmission through, or reflection from the web, and a grating arrangement modulates the radiation received by the photocells, thereby to modulate the output signal of each cell by an A.C. component.

Abstract: Automatic defect detecting inspection apparatus for detecting defects or imperfections contained in or on a moving slab or strip. The defect detection apparatus utilizes a linear light source for illuminating a selected portion of the slab or sheet surface and an array of optically sensitive elements arranged in side-by-side relationship to scan the surface of the sheet or slab in a direction transverse to the direction of movement to produce an output video signals corresponding to the optical intensity of the area scanned. An anamorphic optical system comprising spaced cylindrical lenses forming a Galilean telescope positioned between the moving material and the optically sensitive elements increases the sensitivity of the optically sensitive elements in the direction of the material movement while maintaining the sensitivity of the optical elements substantially unchanged in the direction transverse to the material movement.

Abstract: This invention relates to a method and apparatus for determining whether a glue drop is present on the reflective inner surface of a closure. Collimated light is projected onto the reflective inner surface of the closure, and a measurement is taken of the amount of light which remains collimated after reflection from the closure. The measurement of the amount of light reflected in this way is used to determine whether a glue drop is present.

Abstract: In a method for testing a continuously forward-moving strand a light beam which passes along a plane that extends approximately perpendicularly to the longitudinal axis of the strand is introduced into the strand. The brightness value is measured on a place of the strand exterior which is distal from the light incidence place by means of at least one photoelectronic element disposed directly on the strand exterior and the measured result is evaluated in a gating circuit which is electrically connected to the photoelectronic element.

Abstract: A device for dynamically measuring the degree of dirt accumulation on bank-notes in which certain areas of the bank-note are illuminated and examined by means of a receiving unit. The light from a succession of adjacent elemental areas of a bank-note so illuminated is dependent upon the degree of dirt accumulation and is converted into a corresponding electric signal. The signal is analyzed to determine the number and amount of changes due to dirt accumulated in creases, and the analyzed signal is integrated to determine whether or not the number and nature of areas of accumulated dirt makes the ban-note unsuitable for further circulation.

Abstract: In a method and apparatus for the detection of yarn defects, which may be effected in combination with a standard yarn clearer or independently thereof, the cross section of the yarn is continuously scanned and an electrical signal is generated representing not only the cross section and length of yarn defects, but also their frequency or periodicity, and these features are used as the criterion for generating a defect signal as an indication of detection of regular or irregular sequences of thick places in the yarn.

Abstract: A monitoring system for detecting the presence of folds, creases, etc., in the surface of a moving web of material such as paper. The system utilizes a laser light beam arranged parallel to the surface of the web and transversely to the direction of movement thereof. A light detector such as a differential photo electric detector senses changes in the light beam caused by impingement on a fold or crease.

Abstract: The invention provides novel apparatus for detecting and marking defects in flat glass advancing on a conveyor, for example a ribbon of float glass. There are two viewing stations on opposite sides of the center of the conveyor and spaced longitudinally so that there is staggered viewing of the two halves of the width of the advancing glass. Light reflected obliquely through each half is received on a viewing screen mounted above the respective side of the conveyor. Images of defects are recognized by examiners or cameras viewing the screens and the defects are marked by operation of appropriate marker guns positioned above the conveyor.

Abstract: Apparatus and method for testing surface defect on an object are disclosed, which comprise an illumination means for illuminating collimated lights onto a surface of the object obliquely to the surface and from two symmetrical directions, a sensor composed of a TV camera or a linear image sensor for sensing diffused reflected lights from the surface of the object in the direction perpendicular to the surface, a classification means for discriminating the sensed image signal by a threshold level which is higher than an average level of the image signal and a threshold level which is lower than the average level to determine the surface defect pattern as a broken cavity pattern or a pit or crack pattern by the discriminated signals, and a discrimination means for calculating L.sup.2 -4.pi.S, where S is an area of the defect and L is a length of the contour, when signal discriminated by the lower threshold level is produced to discriminate the pit pattern and the crack pattern by determining whether L.sup.2 -4.

Abstract: An apparatus for inspecting motion picture film so as to locate edge cuts and tears, sprocket hole tears, improper splices and tape fragments or other objectionable foreign material on the film surface, which apparatus comprises a supporting frame with a front panel disposed in a generally vertical plane between parallel spaced end frame members and extending above a work table on which are mounted a plurality of work units and control apparatus therefor, the work units being disposed between the end frame members and along a generally horizontal path traversed by the film which is fed from a supply reel and gathered onto a take-up reel, both of which are driven by circuit controlled motors, the work units comprising a film cleaning unit, a defect detector unit, a viewer or an illuminated film viewing light box unit, a splice counter and footage measuring unit and a film tension sensor unit, with integrated circuit electronics for control of all machine functions and with safety devices including a transparen

Abstract: A television inspection system for detecting flaws on a cable and the like, without contact, utilizes means for obliquely, evenly illuminating the object; a backing member having the same average reflectivity as the object and video sensor-signal processing means for detecting changes in the reflected illumination to sense flaws upon the object's surface.

Abstract: A flaw detection system is provided in which a source of radiation is scanned across a web of moving material being examined for repeat defects. The web is divided into lanes for processing purposes, and flaw information derived from the surface of material being examined is processed to provide a two-coordinate matrix location (lane and down-web), which is stored. This circuitry without the matrix outputs has other applications. Separation distances of a repeat flaw in the same lane are compared with a predetermined list, and if a match occurs, future flaw locations are projected in that lane. A repetition of a predetermined number of flaw repeats in a given lane signals an alarm. A predetermined number of misses in a row will result in the clearing of that lane of the particular flaw that failed to repeat.

Abstract: The purpose of this invention is to reveal the surface properties, such as smoothness and resulting printability of a rapidly moving strip of material, such as paper. To accomplish this, the production process is continuously monitored, without error due to environmental conditions such as dust and dirt on optical surfaces, temperature affects, lamp degradation, etc. An index of printability relative to smoothness is obtained by integrating the plateau areas in the optical field of view. A unique combination of approach angle, selected wave length of infra red radiation, horizontal polarization of search beam, and use of four optical paths to obtain mathematical model equivalency, is employed.