Apparatus for detecting and evaluating indicia on processed photographic film or the like

Claim 2

Apparatus for detecting and evaluating indicia applied at longitudinally spaced intervals to one side of a web which travels lengthwise along a predetermined path and wherein each of said indicia has a predetermined width as considered at right angles to the direction of travel of the web and an opacity deviating from that of the remainder of said one side of the web, comprising a plurality of identical photoelectric detectors adjacent to a portion of said path so that each detector scans a different strip-shaped section of said one side of the web for the presence of indicia and produces first signals in response to detection of indicia and second signals in response to detection of the absence of indicia, the width of said strip-shaped sections being less than said predetermined width and each of said detectors comprising a light source arranged to direct a beam of light against the respective strip-shaped section of the travelling web, a light sensitive element which produces said first and second signals and an amplifier system arranged to regulate the intensity of light issuing from said source so as to respectively equalize said first and second signals; and common evaluating means connected with said detectors to produce a further signal in response to reception of at least one first signal, each of said amplifier systems comprising time-delay means arranged to delay the equalization of said first and second signals so as to insure that first signals produced on detection of said indicia are transmitted to said evaluating means.

Claim 3

Apparatus as defined in claim 1, wherein each of said detectors further comprises a concave reflector arranged to deflect the respective light beam against the corresponding strip-shaped section, the curvature of said reflector being identical with or approximating the curvature of an ellipse having a first focus at least closely approximating the respective light source and a second focus at least closely approximating the point where the reflected light beam impinges upon said one side of the web.

Claim 4

Apparatus as defined in claim 2, wherein the light beams emitted by said sources are parallel with the direction of travel of the web.

Claim 5

Apparatus as defined in claim 2, wherein the curvature of each of said reflectors equals or approximates that of the larger auxiliary circle of the respective ellipse.

Claim 6

Apparatus as defined in claim 2, wherein each of said detectors further comprises a transparent tubular envelope for the respective light source.

Claim 7

Apparatus as defined in claim 5, wherein each of said envelopes comprises a lens at one end thereof, said lens being disposed between the respective light source and the associated reflector.

Claim 8

Apparatus as defined in claim 6, further comprising housing means for said envelopes, said housing means having elongated recesses extending in substantial parallelism with the direction of travel of the web and each accommodating one of said envelopes.

Claim 9

Apparatus as defined in claim 2, further comprising opaque partitioning means disposed between the light sources of said detectors.

Claim 10

Apparatus as defined in claim 8, further comprising housing means for said detectors, said housing means having slots for said partitioning means.

Claim 11

Apparatus aS defined in claim 1, wherein the width of said strip-shaped sections at most equals one-half of said predetermined width.

Claim 12

Apparatus as defined in claim 1, wherein the opacity of the major part of said one side of the web is less than the opacity of said indicia.

Claim 13

Apparatus as defined in claim 1, wherein each of said detectors further comprises means for shielding the respective light sensitive element against direct impingement of light issuing from the respective light source and against direct impingement of light which is reflected by the travelling web, each of said light sensitive elements being exposed to stray light which is reflected by said one side of the web.

Claim 14

Apparatus as defined in claim 1, wherein said evaluating means comprises an OR-gate.

Claim 15

Apparatus as defined in claim 13, wherein said evaluating means further comprises a circuit which is arranged to receive from said OR-gate signals exceeding a predetermined threshold value.

Claim 16

Apparatus for detecting and evaluating indicia applied at longitudinally spaced intervals to one side of a web which travels lengthwise along a predetermined path and wherein each of said indicia has a predetermined width as considered at right angles to the direction of travel of the web and an opacity deviating from that of the remainder of said one side of the web, comprising a plurality of identical photoelectric detectors adjacent to a portion of said path so that each detector scans a different strip-shaped section of said one side of the web for the presence of indicia and produces first signals in response to detection of indicia and second signals in response to detection of the absence of indicia, the width of said strip-shaped sections being less than said predetermined width and each of said detectors comprising a variable-intensity light source arranged to illuminate the respective strip-shaped section of the web, a light sensitive element located in the path of light which is reflected by the web to respectively produce said first and second signals in response to exposure to light which is respectively reflected by an indicium and by an unmarked portion of the respective strip-shaped section, and an amplifier system having means for comparing the intensities of signals furnished by the light sensitive elements of all detectors with the intensity of a predetermined signal and for varying the intensities of said light sources as a function of the results of such comparison, each of said amplifier systems further comprising two transistors with the base of one of said transistors connected to the respective light sensitive element and the emitter of said one transistor connected to said signal comparing means, the collector of said one transistor being connected with the base of the other transistor and said other transistor having an emitter-collector circuit which includes the respective light source, each of said amplifier systems further comprising time-delay means connected between the base and collector of said one transistor; and common evaluating means connected with said detectors to produce a further signal in response to reception of at least one first signal.

Claim 17

Apparatus for detecting and evaluating indicia applied at longitudinally spaced intervals to one side of a web which travels lengthwise along a predetermined path and wherein each of said indicia has a predetermined width as considered at right angles to the direction of travel of the web and an opacity deviating from that of the remainder of said one side of the web, comprising a plurality of identical photoelectric detectors adjacent to a portion of said path so that each detector scans a different strip-shaped section of said one side of the web for the presence of indicia and produces first signals in response to detection of indicia and second signals in response to detection of the absence of indicia, the width of said strip-shaped sections being less than said predetermined width and each of said detectors comprising a variable-intensity light source arranged to illuminate the respective strip-shaped section of the web, a light sensitive element located in the path of light which is reflected by the web to respectively produce said first and second signals in response to exposure to light which is respectively reflected by an indicium and by an unmarked portion of the respective strip-shaped section, and an amplifier system having means for comparing the intensities of signals furnished by the light sensitive elements of all detectors with the intensity of a predetermined signal and for varying the intensities of said light sources as a function of the results of such comparison, each of said amplifier systems further comprising two transistors with the base of one of said transistors connected to the respective light sensitive element and the emitter of said one transistor connected to said signal comparing means, the collector of said one transistor being connected with the base of the other transistor and said other transistor having an emitter-collector circuit which includes the respective light source, each of said amplifier systems further comprising time-delay means connected between the base and collector of said one transistor; and common evaluating means connected with said detectors to produce a further signal in response to reception of at least one first signal.

Claim 18

Apparatus as defined in claim 15, wherein said signal comparing means is a Zener diode.

Claim 19

Apparatus as defined in claim 15, wherein each of said time-delay means comprises a capacitor.

Claim 20

Apparatus for detecting and evaluating indicia applied at longitudinally spaced intervals to one side of a web which travels lengthwise along a predetermined path wherein each of said indicia has a predetermined width as considered at right angles to the direction of travel of the web and an opacity deviating from that of the remainder of said one side of the web, comprising a plurality of identical photoelectric detectors adjacent to a portion of said path so that each detector scans a different strip-shaped section of said one side of the web for the presence of indicia and produces first signals in respoNse to detection of indicia and second signals in response to detection of the absence of indicia, the width of said strip-shaped sections being less than said predetermined width and each of said detectors comprising variable-intensity light source arranged to illuminate the respective strip-shaped sections of the web, a light sensitive element located in the path of light which is reflected by the web to respectively produce said first and second signals in response to exposure to light which is respectively by an indicium and by an unmarked portion of the respective strip-shaped section, and an amplifier system having means for comparing the intensities of signals furnished by the light sensitive elements of all detectors with the intensity of a predetermined signal and for varying the intensities of said light sources as a function of the results of such comparison; and common evaluating means connected with said detectors to produce a further signal in response to reception of at least one first signal.

Claim 21

Apparatus for detecting and evaluating indicia applied at longitudinally spaced intervals to one side of a web which travels lengthwise along a predetermined path wherein each of said indicia has a predetermined width as considered at right angles to the direction of travel of the web and an opacity deviating from that of the remainder of said one side of the web, comprising a plurality of identical photoelectric detectors adjacent to a portion of said path so that each detector scans a different strip-shaped section of said one side of the web for the presence of indicia and produces first signals in respoNse to detection of indicia and second signals in response to detection of the absence of indicia, the width of said strip-shaped sections being less than said predetermined width and each of said detectors comprising variable-intensity light source arranged to illuminate the respective strip-shaped sections of the web, a light sensitive element located in the path of light which is reflected by the web to respectively produce said first and second signals in response to exposure to light which is respectively by an indicium and by an unmarked portion of the respective strip-shaped section, and an amplifier system having means for comparing the intensities of signals furnished by the light sensitive elements of all detectors with the intensity of a predetermined signal and for varying the intensities of said light sources as a function of the results of such comparison; and common evaluating means connected with said detectors to produce a further signal in response to reception of at least one first signal.

Claim 22

Apparatus as defined in claim 18, wherein said evaluating means comprises a transistor and each of said light sensitive elements is connected with the base of said transistor by way of a discrete diode and with the emitter of said transistor by way of at least one resistor.

Claim 23

Apparatus as defined in claim 19, wherein said resistors are connected in parallel and the collector of said transistor is arranged to transmit the maximum-intensity signals received from said light sensitive elements.

Claim 24

Apparatus for detecting and evaluating indicia applied at longitudinally spaced intervals to one side of a web which travels lengthwise along a predetermined path and wherein each of said indicia has a predetermined width as considered at right angles to the direction of travel of the web and an opacity deviating from that of the remainder of said one side of the web, comprising a plurality of identical photoelectric detectors adjacent to a portion of said path so that each detector scans a different strip-shaped section of said one side of the web for the presence of indicia and produces first signals in response to detection of indicia and second signals in response to detection of the absence of indicia, the width of said strip-shaped sections being less than said predetermined width and each of said detectors comprising a light source arranged to emit a beam of light, a concave reflector arranged to deflect the respective light beam against the corresponding strip-shaped section, the curvature of said reflector being identical with or approximating the curvature of an ellipse having a first focus at least closely approximating the respective light source and a second focus at least closely approximating the point where the reflected light beam impinges upon said one side of the web, and a light sensitive element located in the path of light which is reflected by said one side of the web and arranged to produce said first and second signals in response to changes in the intensity of reflected light, housing means for said light sources and said light sensitive elements, said housing means having duct means extending substantially at right angles to the direction of lengthwise travel of the web to direct reflected light against said light sensitive elements; and common evaluating means connected with said detectors to produce a further signal in response to reception of at least one first signal.

Claim 25

Apparatus for detecting and evaluating indicia applied at longitudinally spaced intervals to one side of a web which travels lengthwise along a predetermined path and wherein each of said indicia has a predetermined width as considered at right angles to the direction of travel of the web and an opacity deviating from that of the remainder of said one side of the web, comprising a plurality of identical photoelectric detectors adjacent to a portion of said path so that each detector scans a different strip-shaped section of said one side of the web for the presence of indicia and produces first signals in response to detection of indicia and second signals in response to detection of the absence of indicia, the width of said strip-shaped sections being less than said predetermined width and each of said detectors comprising a light source arranged to emit a beam of light, a concave reflector arranged to deflect the respective light beam against the corresponding strip-shaped section, the curvature of said reflector being identical with or approximating the curvature of an ellipse having a first focus at least closely approximating the respective light source and a second focus at least closely approximating the point where the reflected light beam impinges upon said one side of the web, and a light sensitive element located in the path of light which is reflected by said one side of the web and arranged to produce said first and second signals in response to changes in the intensity of reflected light, housing means for said light sources and said light sensitive elements, said housing means having duct means extending substantially at right angles to the direction of lengthwise travel of the web to direct reflected light against said light sensitive elements; and common evaluating means connected with said detectors to produce a further signal in response to reception of at least one first signal.