Abstract: A focus detecting device for optical devices such as cameras and microscopes, which like the human eye, can detect a point of focus in response not only to the contrast of an object but also to differences in hue. The invention provides a device which provides a measurement of contrast from an image projected onto sensors separated according to different ranges of wavelength. Focus is detected by the sensors as they measure the differences in the intensity of incident light reflected from an object under focus. The sensors also provide a measure of contrast in response to different wavelength ranges.

Abstract: A relay optical system used for focus detection including an optical lens system for forming the image of the exit pupil of a photographing lens, all or a part of said lens optical system for forming a secondary image of an image which is formed on a focusing plane by the photographing lens and a reflecting mirror provided in a plane where the image of said exit pupil is formed. The reflecting mirror is made up of a plurality of reflecting mirror portions which are obtained by dividing the reflecting mirror. The mirror portions divide the image of the exit pupil and have different optical axes, so that an image formed by the photographing lens is formed into secondary images the number of which is equal to the number of mirror parts. Sensor arrays are provided to receive the secondary images, respectively, to detect focusing from correlation of the images.

Abstract: A focus detecting device comprising split prisms between an optical lens and an object image formed on the focal plane of the lens. The image is divided into two images and a plurality of light receiving elements or two arrays are disposed on the image forming surface. The outputs of the elements or arrays are processed to provide an electrical signal indicative of focus status.

Abstract: A focus detecting device having two concave mirrors for reforming the image of an object which is formed between a lens and the focal plane of lens, and for dividing said image two same secondary images. Two light receiving element arrays are provided in the image forming planes of the secondary images. A signal processing circuit subjects the outputs of the light receiving element arrays to produce a signal indicating whether or not the lens is focussed on the object. By means of the two concave mirrors adapted to form said secondary images, the two secondary images are shifted in the opposite directions on the light receiving element arrays at the time of defocussing so that the difference between the outputs of the two light receiving element arrays is not zero. At the time of proper focus the two secondary images are located at equivalent positions on said light receiving element arrays so that the difference between the outputs of the two light receiving element arrays is zero.

Abstract: A display device for a camera in which both an electrical focus detecting and indicating device and an exposure meter or automatic exposure control device are incorporated into a single display element provided in the view finder of the camera. Switching means is coupled to receive on input contacts thereof signals representing both a focus indication and a shutter speed. Normally, the display device displays information in response to the focus detection and indication signal. When the shutter button of the camera is depressed to a first position, the switching means is changed over to display the shutter speed. The display device may be implemented either by an array of LED display elements or a liquid crystal display element.

Abstract: A camera including an automatic focalizing device with which the camera will automatically focus only upon objects within a predetermined range set by the photographer. The wiper of a potentiometer is coupled to the lens so that its operative position is determined by the position of the lens. The wiper is also electrically coupled to respective positive and negative comparison inputs of first and second comparators to the other inputs of which are applied voltages from a second potentiometer which are determinative of the selected range at which focalization may be achieved. The combined outputs of the comparators are coupled to the control input of an analog switch device coupled between the output of a focus detector and the control circuit of a lens positioning motor.

Abstract: A focus detecting device for a lens system having a subsystem for dividing the image of an object into two optically equal images and for shifting the two images of the object in the opposite directions or shifting only one of the two images of the object. Two photoelectric conversion element groups are adapted to convert the variations in relative position of the two images of the object into electrical signals. An optical system projects the images of the object onto the two photoelectric conversion element groups, in which the following outputs are obtained from the outputs of photoelectric conversion elements forming the two photoelectric conversion element groups by using a calculating circuit: ##EQU1## where: n is the number of photoelectric conversion elements forming each photoelectric conversion element group, m is the number in order of a photoelectric conversion element and, i.sub.1 through i.sub.n and i'.sub.1 through i'.sub.

Abstract: A focus detecting device in a single lens reflex camera having a lens system and an optical image splitter for splitting an object image into various partial images disposed at a position optically equivalent to that of a film surface in said single lens reflex camera. An array of photo-electric conversion devices are arranged into at least two rows, each row having a plurality of photo-electric conversion elements. The rows are disposed symmetrically with respect to a center line. The device includes an image projecting device for projecting the partial images onto the photo-electric conversion arrays. The projecting device has an optical axis which optically corresponds to said center line, the output of said conversion array defined by ##EQU1## The output of the conversion array has a maximum value when proper focus is obtained.

Abstract: A focus detecting device having a release lens for reforming the image of an object which is formed between a lens and the focal plane of the lens. A mirror is provided between the release lens and an image reforming plane for dividing the primary image into two secondary images. Two light receiving element arrays provided in the image forming planes of said secondary images provide outputs to a signal processing circuit for comparison to produce a signal indicating whether or not the lens is focussed on the object. The mirror for dividing the primary image into two secondary images, shifts the two secondary images in opposite directions on the light receiving element arrays at the time of defocussing so that the difference between the outputs of said two light receiving element arrays is not zero.

Abstract: A focus detection optical system where the image of an object is divided into two images thereof, and the two images are shifted in the opposite directions or one of the two images is shifted. The two images are projected respectively onto two photoelectric conversion element groups adapted to convert the variations in relative position of the two images into electrical signals. A focus detecting device comprises: a calculating circuit for providing outputs V.sub.out1(m), V.sub.out2(m) and V.sub.out3(m) from the outputs of photoelectric conversion elements forming the photoelectric conversion element groups,V.sub.out1(m) =.vertline.log(i'.sub.m /i.sub.m+1).vertline.V.sub.out2(m) =.vertline.log(i.sub.m /i'.sub.m+1).vertline.V.sub.out3(m) =V.sub.out1(m) -V.sub.out2(m),where: m=1, 2, 3, . . . and (n-1), being the number in order of the photoelectric conversion elements, n is the number of the photoelectric conversion elements forming each photoelectric conversion element group, and i.sub.1 through i.sub.

Abstract: A manual setting device is provided in a camera wherein the shutter speed is electrically controlled. The manual setting device can be used as an alternate control in an automatic exposure control camera or may be used in a non-automatic electrically controlled camera. For a camera having an electrically controlled shutter speed, first and second counters are provided. The first counter is preset to a computed or desired shutter speed, and the output of the first counter corresponding to the shutter speed is displayed by LEDs in the viewfinder of the camera. The second counter operates in response to an oscillator, and when the count accumulated in the second counter equals that of the first counter, the shutter bottom curtain electromagnet is operated. The manual setting device is a pulse generator controlled by a switch to preset the counter.

Abstract: A focus detecting device in a camera having an optical member or an optical system for obtaining two images from an object and an optical member for displacing said two images in opposite directions or displacing one of said two images. Two minute photoelectric conversion element groups are used for converting variations in light quantity of portions of the object into electrical signals. A photographing lens projects the image of the object onto the minute photoelectric conversion element groups. A circuit calculates outputs ##EQU1## from the outputs of minute photoelectric conversion elements forming the minute photoelectric conversion element groups. A circuit which has a first calculation function for calculating V.sub.out-3 =V.sub.out-1 +V.sub.out-2 and a second calculation function for calculating V.sub.out-4 =V.sub.out-1 -V.sub.out-2 so that when V.sub.out-3 becomes higher than a predetermined value, different outputs are produced under conditions that V.sub.out-4 >.epsilon..sub.1, .epsilon..sub.1 .

Abstract: An abnormal operation warning apparatus is disclosed which is capable of evaluating the photographic result for each photographing process of a camera. The warning apparatus includes a first voltage generator for producing a first voltage signal having a level corresponding to the film sensitivity set before photographing, and a second voltage generator for producing a second voltage signal having a level corresponding to the amount of light exposed on the film for each photographing process. The two voltage signal levels from the first and second voltage generators are compared by a comparator. The photographic effect is evaluated by a discriminator in response to the comparison result, thereby preventing any subsequent abnormal or undesirable photographic result.

Abstract: A pair of wedge prisms 11, 11' are disposed at an optical position equivalent to that of the film 10 in an SLR camera, and light from the object is directed thereon by a mirror 4 or the like. The prisms split the object image into two halves which are projected onto a two row array of thin photocells or the like, whereby the relative lateral displacement between the image halves as well as their level of contrast is a function of the degree of correct image focus. The latter is sensed by subtractively of differentially comparing the outputs of paired, laterally offset photocells in the two rows, such pairing being implemented in both directions. The output summation signal exhibits an easily detectable sharp peak when the object is properly focused, thereby enabling automatic focal point detection.

Abstract: A finder display for both shutter speed and diaphragm priority modes in an SLR camera includes a liquid crystal or the like indicator cell 12 having closely side-by-side Tv and Av scales 13, 14 sharing in common the first E, OVER and UNDER characters 15, 16 and 17 and an illuminable dot indicator 18, such as an LED. The scales are longitudinally offset such that the number of laterally aligned numerals in both scales never exceeds four, which serves to further reduce the display width and its projection into the finder viewing field.

Abstract: An electrically controlled camera device is disclosed which includes a counter for counting the number of pulses representative of the preferentially selected one exposure condition of a shutter speed and a diaphragm aperture level to control the preferentially selected one exposure condition, and a digital operation circuit for calculating the other exposure condition in the form of a number of digital pulses in accordance with the output pulses from the counter and with digital data signals representative of the sensed scene brightness and the film sensitivity used. During automatic exposure, the number of pulses counted by the counter is controlled by the combination of a pulse generator and a single-throw mechanical switch connected between the pulse generator and the counter, and the number of output digital pulses from the digital operation circuit is counted by another counter for controlling the other exposure condition.

Abstract: In a single lens reflex camera a focus detecting device is provided to identify or control the in-focus condition of a lens. The detecting device operates on the same principle as that used in visual focusing, namely the bringing together of a split image or the observation of the clarity of an image or both. A group of photo-electric light detecting elements is positioned to receive a part of the object's image, which part corresponds to that watched by the photographer in determining an in-focus condition. For split image focusing the group is divided into two lines of elements located adjacent to and on opposite sides of the line splitting the image. Each line of elements effectively measures the spatial light intensity impinging thereon. When the spatial light intensity detected by both lines are the same, an in-focus condition is detected. For image clarity focusing the adjacent elements of a line of photo electric elements are connected so as to subtractively combine their photo current outputs.

Abstract: An electronic strobe adapted to be used with a camera for providing flash illumination. The electronic strobe has its own circuitry for automatically determining the extent of flash exposure with a part of this circuitry being adjustable for introducing a variable exposure-determining factor such as film speed and diaphragm aperture. When the electronic strobe is used with a camera which does not have its own electronic shutter-controlling circuitry, then the controls of the strobe are used for introducing a variable factor of the latter type. However, when the electronic strobe is used with a camera which does have its own electronic circuitry for automatically determining the exposure time, then that part of the latter circuitry of the camera which introduces a variable factor of the above type is electrically connectable with the circuitry of the strobe to control the latter according to such a variable from the circuitry of the camera rather than from the circuitry of the strobe itself.