Abstract: The present invention relates to a device for measuring object distance or an in-focus position used for a camera in which the object distance of focus adjusting condition are measured in a plurality of distance measuring areas in the photographing scene. The device is so constructed as to judge a main object from weight data in correspondence not only with the object distance of each distance measuring area but with the position thereof in the photographing scene. Further, when there is an object nearer than a predetermined distance, the main object is judged from whether the object has a size larger than a predetermined size in the photographing scene. Furthermore, it is judged from the difference between the object distances of adjacent distance measuring areas whether the objects are the same object.

Abstract: In a camera having an automatic focus detection device of active type, an auxiliary light source to project light to the object for the purpose of automatic focus detection is shared to a self-timer indicator.

Abstract: A focus detecting system having a passive type automatic focusing function and an active type automatic focusing function. When the passive type automatic focusing function is used, focus detection is performed using light which is incident from a position close to an optical axis of a photographic lens, while in the case of using the active type automatic focusing function, focus detection is performed using light which has passed through a position far from the optical axis of a photographic lens. The focus detection value is corrected using a preset correction value to set the photographic lens in the best image position.

Abstract: A developing apparatus which includes a toner replenishing device for replenishing toner into the developing apparatus, a toner concentration detecting sensor for generating an output coresponding to the toner amount in a developing material stirred and transported through the developing apparatus, with the output containing a varying output periodically produced and stable output, a discriminating element for deriving the stable output of the outputs from the toner concentration detecting element, and a comparator for outputting a feeding signal to the toner replenishing device through comparison between the output from the discriminating element and a preliminarily set reference value.

Abstract: A focus detecting device capable of correcting an error, between an in-focus position of a photographic lens detected by a focus detecting means and an image field position affording the best image. Focus detection is made using plural focus detecting areas provided on and off the optical axis of the photographic lens, to obtain an in-focus position. Then, the thus-obtained in-focus position of the photographic lens is corrected using an appropriate correction value out of those preset and stored in a ROM in the lens according to whether the focus detecting area used in the focus detection is an axial or off-axial area, or according to the focal length of the photographic lens as well as the photographing mode. And the photographic lens is thereby set to the best image field position.

Abstract: An automatic focus detection system for use in a camera system comprises focus detecting unit having one light receiving element corresponding to, in an objective field, a focus detection area whose center is deviated from the optical axis of the objective lens, the position of the focus detection area being changed in accordance with the change of the focal length of the objective lens; and a light projecting unit for projecting light towards the object field so that the region of the projected light covers the focus detection area, if the position of the focus detection area is changed in accordance with the change of the focal length of the objective lens.

Abstract: A focus adjusting system is provided with both a passive AF capability wherein ambient light is utilized and an active AF capability wherein an LED element for projecting light off the optical axis of a photo-taking lens and light reflected from an object after having been projected by the LED element are utilized. The focus detecting apparatus includes a secondary image forming element and an aperture opening disposed in the vicinity of the secondary image forming element. The aperture opening is symmetrically positioned relative to the optical axis of the photo-taking lens and lies on a straight line which contains the optical axis of the photo-taking lens and which is perpendicular to a straight line connecting the optical axis of the photo-taking lens and a projecting light optical axis. The aperture opening has a pair of inner regions and a pair of outer regions. A first cut-off filter having a property of cutting off rays of light of a wave-length projected from the LED element is provided.

Abstract: A focus detecting device which is capable of focus detection under both passive and active type of autofocussing modes. The device has a light projecting element which projects light at specific wavelengths in a boundary region between visible light and infrared light, and a sensor which is responsive to both ambient light and the light projected from the light projecting element. A correction unit corrects chromatic aberration information stored in the photographing lens on the basis of the results of arithmetic operation of the output signals from the sensor generated with the light projecting member activated and deactivated. In the active type of autofocussing mode, utilizing the light projected from the light projecting element, the result of the focus detection is corrected by the corrected chromatic aberration information while the result of the focus detection is not subjected to any correction in the passive type of autofocussing mode utilizing the ambient light.

Abstract: A focus detecting system having a passive type automatic focusing apparatus and an active type automatic focusing apparatus. When the passive type automatic focusing apparatus is used, focus detection is made using light which is incident from a position close to an optical axis of a photographic lens, while in the case of using the active type automatic focusing apparatus, focus detection is made using light passed through a position far from the optical axis of a photographic lens. The focus detection value is corrected using a preset correction value to set the photographic lens in the best image position.

Abstract: A focus detecting device having a function of detecting blur, including a focus detecting member, a detection member which receives two image signals of an identical object obtained in time series by an identical optical system so as to detect degree of coincidence between the two image signals, and a selector member for selecting whether operation of the focus detecting member and the selection member is performed continuously or operation of only the focus detecting member is performed.

Abstract: A focus detecting device capable of correcting an error, between an in-focus position of a photographic lens detected by a focus detecting means and an image field position affording the best image. Focus detection is made using plural focus detecting areas provided on and off the optical axis of the photographic lens, to obtain an in-focus position. Then, the thus-obtained in-focus position of the photographic lens is corrected using an appropriate correction value out of those preset and stored in a ROM in the lens according to whether the focus detecting area used in the focus detection is an axial or off-axial area, or according to the focal length of the photographic lens as well as the photographing mode. And the photographic lens is thereby set to the best image field position.

Abstract: A focus detection device for a camera, especially for a single lens reflex camera is disclosed.The focus detection device provides a light measuring means for measuring the color temperature of light beams being incident thereinto and a correction means for correcting the color temperature of said incident light for focus detection so as to have a predetermined constant color temperature. This correction removes possible errors in focus detection due to the chromatic aberration of an objective lens.

Abstract: A focus detection system for a camera, especially for a single lens reflex camera, is disclosed.The focus detection system comprises a light projection means for illuminating an object at the active AF and means for switching positions and/or sizes of iris apertures for focus detection according to the type, F-number, focal length, shift amount etc., of an interchangeable lens assembly in order to remove possible light beams such as flares and ghosts generated by surface reflections due to lenses comprising the interchangeable objective lens.

Abstract: In a focus condition detecting arrangement for use in a photographic camera, a focus condition detecting device including photo-sensor arrays having sensitivity with respect to a visible light and an infrared light from a target object to be photographed produces a focus condition detection signal based on an output of the photo-sensor arrays. A contrast detecting device which detects the visible light and the infrared light from the target object for detecting contrasts of the target object with respect to the respective lights, and a correcting means corrects the focus condition detection signal based on the output of the contrast detecting device, so that a corrected focus condition detection signal of the target object with respect to the visible light region is obtained.

Abstract: An image position detector includes a light receiving element for receiving an image of an object and for producing an electric signal generated by the image, and a signal processing circuit for processing the electric signal and for producing a position signal representing a position of the image on the light receiving element. The light receiving element is defined by a semiconductor device having an n-type substrate and p-type region formed in the substrate. A current generated between the n-type substrate and p-type region is in relation to the distance to the image from the p-type region. The signal processing circuit receives the generated current and determines the position of the image by the level of the generated current.

Abstract: A photographic camera having an automatic rangefinder system wherein a light emitter projects a beam of light through a convergent lens to illuminate a target object. This beam of light is detected through another convergent lens by one of a group of photoresponsive elements forming a light receiver. Depending upon which photoresponsive element of the light receiver detects the reflected beam of light, the range of the target object to be photographed from the photographic camera is indicated. The light emitter and the light receiver are supported by a single support member in laterally offset relation to each other and the lens elements for converging the projected beam of light and the reflected beam of light, respectively, are integrally formed of a synthetic resin. The rangefinder elements are assembled into a rangefinder module.

Abstract: An improvement is made in a camera wherein the exposure is controlled by an electronic circuit comprising a photoelectric element so situated as to receive a light reflected from the surface of photographic film in the camera.Conventional shortcomings of the above-mentioned camera that a time delay from operation of the electronic switching circuit to an actual completion of closing of the already opened shutter has been liable to cause an over-exposure and that an exposure period shorter than the delay has been impracticable can be eliminated by employing another photoelectric element which continuously receives a light from the object and influences a current to flow into a timer circuit.Moreover, by means of a change-over switch, the circuit is switched so as to be controlled substantially by the second photoelectric element in case the photographic object is so bright as to necessitate a high speed exposure faster than the time delay.

Abstract: An indicating device for producing a warning indication of possible over or under exposures in an automatic exposure adjusting device in a photographic camera. The brightness of light rays from a photographic object which are transmitted through a diaphragm aperture, is measured for a duration in which a diaphragm is stopped down from its fully open position to a diaphragm aperture preset by a diaphragm presetting ring. When light measuring output reaches a proper level with respect to a film speed of a film used and a pre-selected shutter speed, a diaphragm control circuit is actuated so as to set the aperture size of the diaphragm. The indicating device provides an indication as to whether or not a proper diaphragm aperture may be obtained during the diaphragm-stopping-down operation so as to effect a proper exposure.