With Automatic Diaphragm Control Patents (Class 352/141)
  • Patent number: 4101910
    Abstract: A diaphragm-adjusting motor varies the setting of an adjustable diaphragm and includes a drive winding and a damping winding. A negative-feedback control circuit generates a scene-light-dependent error signal and energizes the drive winding of the adjusting motor in dependence upon the error signal. During adjusting motion of the adjusting motor, a damping voltage is induced in the damping winding. The damping voltage is utilized to modify the error signal in a sense opposing energization of the adjusting motor, so as to damp the adjusting motion of the adjusting motor and thereby prevent adjustment overshoots during normal operation. When the error signal reaches a preselected value, further energization of the drive winding of the adjusting motor is prevented. During normal operation, the lowering of the error signal effected by the damping voltage as the adjusting motor performs an automatic adjustment prevents the error signal from reaching the preselected value.
    Type: Grant
    Filed: March 7, 1977
    Date of Patent: July 18, 1978
    Assignee: Robert Bosch GmbH
    Inventor: Hermann Mayer
  • Patent number: 4100558
    Abstract: Herein disclosed is an electromagnetic rotary motion device including permanent magnets establishing a pair of spaced concentric and coextensive circular or semicircular air gaps and a rotor unit including armatures which are movable in a circular path in and along the spaced air gaps in response to an electric control signal impressed thereon. A typical application of the rotary motion device is a diaphragm-assisted exposure control arrangement of an optical instrument, such as for example as a still camera, a cinema motion camera or a television camera, wherein the diaphragm is driven by the rotor unit for providing a degree of exposure which is optimum for the brightness of an object to be photographed or televised.
    Type: Grant
    Filed: October 17, 1975
    Date of Patent: July 11, 1978
    Inventors: Hiroshi Koike, Shoji Suzuki, Takeki Asakawa
  • Patent number: 4094594
    Abstract: A movie camera has a film advance motor which can only operate when a relay is closed that is controlled by a transistor. This transistor can be operated by the release switch of the camera and by a circuit which senses the end of a fade-out cycle so that the film-advance motor is automatically stopped at the end of the fade-out cycle. To this end a variable diaphragm, which is provided with automatic light-adjusting circuitry is operated by a driving coil adjacent which is provided a damping coil that causes a control circuit to change the level of an output signal when the diaphragm aperture is fully closed so that at this time the film-advance motor is automatically stopped.
    Type: Grant
    Filed: April 12, 1976
    Date of Patent: June 13, 1978
    Assignee: Robert Bosch GmbH
    Inventors: Hermann Mayer, Hans-Friedrich Kiefer
  • Patent number: 4087164
    Abstract: A motion picture camera wherein a part of the light entering the camera lens from the subject being photographed is reflected by a reflector on the shutter to a light sensitive element of exposure metering means. In order to insure that, for a given degree of brightness of the scene, the same quantity of light reaches the sensitive element regardless of whether the shutter is in motion or is stationary, an adjustable reflector is interposed between the shutter and the light sensitive element. This adjustable reflector is shifted from one position to another position by operation of the camera release member. A bendable ear is provided for calibration purposes.
    Type: Grant
    Filed: August 31, 1976
    Date of Patent: May 2, 1978
    Assignee: Rollei-Werke Franke & Heidecke
    Inventors: Kurt Bode, Heinz Vehrke
  • Patent number: 4084893
    Abstract: A control system is described for automatically setting the exposure of a motion picture camera. The circuits shown include, as basic elements, a photoresponsive device, an amplifier connected thereto, and a stepping motor for actuating the diaphragm of the camera.
    Type: Grant
    Filed: April 22, 1976
    Date of Patent: April 18, 1978
    Assignee: Braun Aktiengesellschaft
    Inventor: Robert Flandorfer
  • Patent number: 4083630
    Abstract: The disclosure relates to a fade circuit for a motion picture camera of the type which includes an automatic exposure control. The fade circuit includes a light emitting diode which illuminates the light sensitive device of the automatic exposure control to augment the ambient light levels normally received by the light sensitive device. The intensity of the light emitted by the light emitting diode is controlled by a variable current source which provides the light emitting diode with continuously increasing or decreasing current for increasing or decreasing the intensity of the light from the light emitting diode. Fade-in is obtained as the light intensity of the light emitting diode is gradually decreased from an initial intensity sufficient to close the diaphragm opening to zero intensity to allow the diaphram to assume an opened condition corresponding to ambient light levels.
    Type: Grant
    Filed: July 24, 1975
    Date of Patent: April 11, 1978
    Assignee: Bell & Howell Company
    Inventors: Robert C. Mau, deceased, Erwin E. Figge
  • Patent number: 4073582
    Abstract: A camera shutter has at least one diaphragm leaf which is mounted for angular displacement about a pivot axis. A cam element is mounted for rotation on the output shaft of a motor and is provided either with a planar surface formed with a spiral cam groove or with a conical surface formed with a conically spiral cam groove. A pin is fixed to the diaphragm leaf at a location laterally offset from the pivot axis and tracks the cam groove.
    Type: Grant
    Filed: March 16, 1977
    Date of Patent: February 14, 1978
    Assignee: AGFA-Gevaert, A.G.
    Inventor: Peter Lermann
  • Patent number: 4072962
    Abstract: A metering device comprises a photoelectric converter circuit for generating a first voltage corresponding to the brightness of a subject to be photographed. The converter circuit includes a photoelectric converter element and a first conductor element for logarithmically converting the output of the photoelectric converter element. The device further comprises a voltage generating circuit including a second semiconductor element and a current source for flowing a current proportional to an absolute temperature to a resistor connected in series to the second semiconductor element. The voltage generating circuit is effective to generate a second voltage comprising the sum of the voltages generated in the resistor and the second conductor element. The difference beween the first and the second voltage is put out by a differential amplifier.
    Type: Grant
    Filed: June 29, 1976
    Date of Patent: February 7, 1978
    Assignee: Nippon Kogaku K.K.
    Inventor: Osamu Maida
  • Patent number: 4066347
    Abstract: The pulse repetition rate of a pulse generator furnishing pulses to a stepmotor which opens and closes the aperture in response to signals indicating that the quantity of light falling on the film is too little or too much respectively, is varied so that the aperture size is changed more rapidly when the difference between the desired and the actual quantity of light falling on the film is great, and is changed more slowly as the quantity of light falling on the film approaches the desired light quantity.
    Type: Grant
    Filed: December 10, 1975
    Date of Patent: January 3, 1978
    Assignee: AGFA-Gevaert, AG
    Inventor: Eduard Wagensonner
  • Patent number: 4059350
    Abstract: A rotating or reciprocating shutter synchronized with the film drive of a cinematographic camera carries or incorporates a light-guiding body of transparent material interposed between the camera objective and its light gate during periods of film transport to direct incident light onto a photoelectric element. The light-guiding body has a flat front surface perpendicular to the optical axis and a generally dihedral internally reflecting rear surface whose faces converge forwardly at a ridge intersecting that axis.
    Type: Grant
    Filed: August 10, 1976
    Date of Patent: November 22, 1977
    Assignees: Karl Vockenhuber, Raimund Hauser
    Inventor: Josef Schild
  • Patent number: 4057333
    Abstract: An exposure time control device in a cinecamera comprises a rotatable shutter, an electric motor for driving the shutter, a power source for the motor, and changing means operatively associated with the rotatable shutter to change the number of revolutions of the motor within a period during which an aperture is opened and closed by the rotatable shutter.
    Type: Grant
    Filed: August 26, 1975
    Date of Patent: November 8, 1977
    Assignee: Nippon Kogaku K.K.
    Inventors: Shigeo Akasaka, Hiroaki Tanaka
  • Patent number: 4052126
    Abstract: A motion picture camera having a film transport mechanism driven by an electric motor having an electronic speed control circuit which may be controlled by the camera operator so as to modify the speed of the motor and consequently the film transport velocity for the selection of various picture frequencies or frames per unit of time both above and below a normal picture frequency for normal shooting thereby permitting both time lapse and slow motion photography during use, the motor speed control circuit permitting the motor to be returned to its normal film speed automatically, together with an automatic aperture control circuit and a picture frequency indicator which may be observed by the operator during the operation of the camera.
    Type: Grant
    Filed: January 23, 1976
    Date of Patent: October 4, 1977
    Assignees: Karl Vockenhuber, Raimund Hauser
    Inventors: Otto Freudenschuss, Gerd Kittag
  • Patent number: 4051496
    Abstract: A remote control camera having a fitting member for mounting thereon a signal receiving device to receive a remote control signal, the body of the signal receiver, when fitted on the camera body, serving to cover the entire eye-piece on the camera body to intercept light entering into the camera body through the eye-piece.
    Type: Grant
    Filed: February 2, 1976
    Date of Patent: September 27, 1977
    Assignee: Nippon Kogaku K.K.
    Inventors: Yozo Iida, Shigeo Akasaka, Yasuhito Kawahara
  • Patent number: 4050795
    Abstract: A single operating switch replaces the main switch connecting the diaphragm control means to the battery and the release switch activating the film transport. All camera circuits are directly connected to the battery when the main operating switch is closed. An electronic switch is connected in series with the film transport motor and is closed only upon receipt of a control signal. In a first embodiment the control signal is furnished by a timing circuit after a predetermined time interval following the activation of the main operating switch. In a second embodiment the control signal is furnished by a NAND-gate which has a first input which receives a "1" signal while the diaphragm is being adjusted and a second input which receives a "1" signal while the electronic switch is open. The NAND-gate thus furnishes a "1" signal to the electronic switch causing it to be conductive at all times except when the initial adjustment of the diaphragm takes place.
    Type: Grant
    Filed: March 4, 1976
    Date of Patent: September 27, 1977
    Assignee: Agfa-Gevaert Aktiengesellschaft
    Inventors: Eduard Wagensonner, Theodor Huber, Bernhard VON Fischern
  • Patent number: 4046464
    Abstract: An automatic exposure control system for controlling the diaphragm of a motion picture camera in accordance with the object brightness level photoelectrically determined from the amount of light passing through the diaphragm is provided with a manually switchable shutter control device having a number ofswitched positions including positions for selection of various speeds of rotation of the camera shutter and for selection of various shutter intervals each effected in one revolution of the shutter in combination with a corresponding number of branch circuits of the exposure metering device controlling operation of the camera diaphragm, whereby it is made possible to make exposures not only at normal light levels but also at low light levels outside the lower limit of the normal light level range.
    Type: Grant
    Filed: June 20, 1975
    Date of Patent: September 6, 1977
    Assignee: Canon Kabushiki Kaisha
    Inventors: Mamoru Shimazaki, Masamichi Toyama, Toshikazu Ichiyanagi, Hideto Iwama
  • Patent number: 4035817
    Abstract: A remote controlled camera having a fitting member for mounting a signal receiving device to receive a remote control signal on the body of the camera, and a light intercepting device incorporated in the camera body to intersect a light path of an incident light beam through an eye-piece and to be actuated in conjunction with mounting operation of a reote control signal receiver on the camera body.
    Type: Grant
    Filed: February 3, 1976
    Date of Patent: July 12, 1977
    Assignee: Nippon Kogaku K.K.
    Inventors: Yozo Iida, Shigeo Akasaka, Yasuhito Kawahara
  • Patent number: 4010480
    Abstract: The control circuit for automatically controlling a diaphragm of a camera for the proper exposure has a servomotor coupled with the diaphragm and provided with a pair of coils each for driving a servomotor coupled with the diaphragm in the opposite direction upon energization thereof so as to open or close the diaphragm and a circuit including a photoelectric element adapted to receive scene light through the diaphragm so as to generate a first and a second input for the pair of coils varying in relation to each other in accordance with the scene light quantity passed through the diaphragm and received by the photoelectric element.
    Type: Grant
    Filed: August 12, 1975
    Date of Patent: March 1, 1977
    Assignee: Yugenkaisha Sato Kenkyusho
    Inventor: Takayoshi Sato
  • Patent number: 4005445
    Abstract: A diaphragm of a camera is controlled by a servomotor which is actuated with an output of an amplifier. A bridge circuit including a photodetector which receives light from the object to be photographed is connected with the amplifier so that the imbalance output of the bridge circuit may be amplified by the amplifier and transmitted to the servomotor to actuate the motor in accordance with the imbalance of the bridge circuit. The output of the photodetector is differentiated by a differentiation circuit connected between the photodetector and the amplifier so that the output of the amplifier may be controlled by the differentiated output which represents the rate of variation in the quantity of light received by the photodetector.
    Type: Grant
    Filed: February 15, 1974
    Date of Patent: January 25, 1977
    Assignee: Fuji Photo Optical Co., Ltd.
    Inventor: Kunio Ando
  • Patent number: 4003646
    Abstract: A cine camera with an exposure regulating device for regulating the aperture during operation with a continuously driven shutter and having means for stopping the rotation of the shutter in an open position to provide long exposures. The means for stopping the rotation of the shutter for long exposures operates automatically when the maximum available aperture is inadequate to provide correct exposure when the shutter is driven continuously.
    Type: Grant
    Filed: October 22, 1975
    Date of Patent: January 18, 1977
    Assignees: Karl Vockenhuber, Dennis Hauser
    Inventors: Otto Freudenschuss, Gerd Kittag
  • Patent number: 4000941
    Abstract: The present invention relates to an automatic exposure adjusting device for a camera or the like, comprising a single photometric mechanism capable of measuring the light corresponding to the light amount entering into a photosensitive material such as film, the first light amount control mechanism driven in accordance with the output of the photometric mechanism for controlling the light amount over the range of the ordinary brightness and the second light amount control mechanism capable of operating in accordance with the output of the photometric mechanism beyond the operation range of the first light amount control mechanism, whereby for the brightness of the object beyond the range of the ordinary brightness the second light amount control mechanism is automatically operated in accordance with the output of the photometric mechanism so as to give a proper exposure.
    Type: Grant
    Filed: February 24, 1975
    Date of Patent: January 4, 1977
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hidekazu Okajima, Tomoshi Takigawa, Noritsugu Hirata, Masamichi Toyama, Toshikazu Ichiyanagi
  • Patent number: 3995285
    Abstract: An optical filter the density of which is variable is provided in the optical path of the taking lens. The density of the filter is controlled to effect optimum exposure with freely selected aperture size and the shutter speed by means of an exposure control circuit. The density of the filter is varied by moving a filter operating member. The filter operating member is controlled by the output of an electric circuit connected with a light measuring circuit including a photodetector to measure the scene brightness.
    Type: Grant
    Filed: May 19, 1975
    Date of Patent: November 30, 1976
    Assignees: Fuji Photo Film Co., Ltd., Toshihiro Kondo
    Inventor: Toshihiro Kondo
  • Patent number: 3987461
    Abstract: An optical filter the density of which is variable is provided in the optical path of the taking lens. The density of the filter is controlled to effect optimum exposure with freely selected aperture size and the shutter speed by means of an exposure control circuit. The density of the filter is varied by moving a filter operating member which is driven by a filter driving means. The stroke of the filter operating member is controlled by means operated by electric pulses generated by an electric circuit connected with a light measuring circuit including a photodetector to measure the scene brightness.
    Type: Grant
    Filed: September 4, 1975
    Date of Patent: October 19, 1976
    Assignees: Toshihiro Kondo, Fuji Photo Film Co., Ltd.
    Inventor: Toshihiro Kondo
  • Patent number: 3978497
    Abstract: An optical filter the density of which is variable is provided in the optical path of the taking lens. The density of the filter is controlled to effect optimum exposure with freely selected aperture size and the shutter speed by means of an exposure control circuit. The density of the filter is varied by moving a filter operating member which is driven by a filter driving means. The start and stop of the filter operating member is controlled by a start controlling electromagnet and a stop controlling electromagnet which are controlled by an electric circuit connected with a light measuring circuit including a photodetector to measure the scene brightness.
    Type: Grant
    Filed: May 19, 1975
    Date of Patent: August 31, 1976
    Assignees: Fuji Photo Film Co., Ltd., Toshihiro Kondo
    Inventor: Toshihiro Kondo
  • Patent number: 3972607
    Abstract: A bridge circuit which includes a photoelectric transducer furnishes input signals to a differential amplifier whose analog output signal varies in correspondence to the bridge unbalance. A first and second bistable threshold circuit changes the analog output signal into digital signals signifying bridge unbalance in a first direction, balance, and unbalance in the opposite direction. A motor is energized to rotate in a direction corresponding to the direction of bridge unbalance. The motor can be utilized to move the objective lens of a slide projector or change the aperture of a diaphragm.
    Type: Grant
    Filed: December 30, 1974
    Date of Patent: August 3, 1976
    Assignee: AGFA-Gevaert, A.G.
    Inventor: Alois Reider
  • Patent number: 3966312
    Abstract: A bridge circuit contains a photoelectric resistor positioned behind the diaphragm and thus having a resistance varying as a function of the light falling on the film. A second arm of the bridge circuit contains a resistor. The bridge circuit output is connected to the inputs of a differential amplifier whose output controls a step motor which adjusts the size of the aperture until the bridge is balanced. For fade-out, an additional resistor is inserted in the second arm by opening a short-circuiting switch, thus causing the bridge to become unbalanced and the step motor to change the aperture until it is again in balance. This balance will take place at a predetermined low illumination suitable for fade-out. Closing the switch will result in fade-in, namely an opening of the aperture until the circuit is again in balance. The output signal from the bridge circuit thus controls the aperture even during fade-in and fade-out.
    Type: Grant
    Filed: December 5, 1974
    Date of Patent: June 29, 1976
    Assignee: AGFA-Gevaert, A.G.
    Inventors: Eduard Wagensonner, Volkmar Stenzenberger
  • Patent number: 3963333
    Abstract: A control system for a cassette-load movie camera having an automatic exposure control system. A variable neutral density filter adjusts the exposure control system to the film sensitivity, and a sensitivity range control adjusts the exposure control system alternatively for a range of high film sensitivities or a range of low film sensitivities. Cassette indicia automatically effect a filter setting and sensitivity range setting upon placement of the cassette within the camera. A switching system controls energization of the exposure control system in relation to energization of the camera drive motor.
    Type: Grant
    Filed: February 25, 1974
    Date of Patent: June 15, 1976
    Assignee: Polaroid Corporation
    Inventors: Arthur C. Mueller, Erwin E. Figge
  • Patent number: 3955887
    Abstract: The present invention refers to a motion picture camera which is characterized in that respectively on the driving shaft to be rotated by means of a driving power from the driving motor and on the shutter shaft to be rotated by means of a rotating power of the above mentioned driving shaft elliptical gears in mutual engagement with each other are provided in such a manner that the ratio of the angular speed to be communicated between the driving shaft and the shutter shaft is continuously increased and decreased while on the above mentioned shutter shaft a non-circular cam to reciprocate the claw for feeding film is provided in such a manner that while the shutter blade is opened the shutter shaft rotates slowly and further the claw for feeding film stops feeding film whereby the effective proper opening angle of the shutter blade is changed largely by means of the above mentioned pair of elliptical gears and the non-circular cam.
    Type: Grant
    Filed: May 22, 1974
    Date of Patent: May 11, 1976
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masamichi Toyama, Tomoshi Takigawa, Noritsugu Hirata, Keiichi Sakaguchi, Toshikazu Ichiyanagi
  • Patent number: 3953116
    Abstract: An exposure control arrangement for motion picture cameras of the type in which the diaphragm is set in accordance with the amount of light passing through the objective is described. The activation of the diaphragm is automatically effected by photoelectric means which are energized upon closure of the shutter and disabled during exposure of the film.
    Type: Grant
    Filed: December 3, 1974
    Date of Patent: April 27, 1976
    Assignee: Braun Aktiengesellschaft
    Inventors: Johann Roth, Robert Flandorfer
  • Patent number: 3942183
    Abstract: A pivoting exposure control system is provided for a photographic apparatus wherein the exposure control system includes a shutter blade apparatus for respectively blocking and unblocking the passage of light through a light entry exposure opening in a camera housing. The shutter blade mechanism includes two shutter blade elements which are disposed for both pivoting and translational motion about a first fixed pivot point spaced laterally apart from the light entering opening in the camera housing. Rotating means pivotally connect at two spaced-apart locations to the respective shutter blade elements so that the shutter blade elements may be simultaneously rotated about a second pivot point spaced laterally apart from the light entering opening and the first pivot point. In this manner, the shutter blade elements may be simultaneously moved over the light entering exposure opening to define a progressive variation of effective apertures.
    Type: Grant
    Filed: July 2, 1974
    Date of Patent: March 2, 1976
    Assignee: Polaroid Corporation
    Inventor: George D. Whiteside
  • Patent number: 3935524
    Abstract: An electronic switching system for the control of a load, such as a motor serving to adjust the diaphragm of a motion-picture camera, comprises a normally inactive comparison circuit including a transistor bridge with a pair of NPN transistors in one pair of adjoining arms and a pair of PNP transistors in the other pair. Two complementary transistors in each half of the bridge, lying between diagonally opposite corners, are provided with a common biasing circuit shunted across that bridge diagonal, the load being connected across the other bridge diagonal. Each biasing circuit includes a resistive voltage divider with taps joined to the bases of the associated bridge transistors and a group of cascaded ancillary transistors connected across a section of the voltage divider containing one of these taps. The first ancillary transistor of each cascaded group has its base connected to an associated input terminal receiving a switching signal and a reference voltage, respectively.
    Type: Grant
    Filed: September 26, 1973
    Date of Patent: January 27, 1976
    Assignees: Karl Vockenhuber, Raimund Hauser
    Inventors: Heinrich Cap, Herbert Krammer, Robert Scheiber