Abstract: A device for measuring distance and light in a single lens reflex camera includes first and second mirrors, a distance measuring element, and a light measuring element which are disposed on a mirror box. The second mirror extends obliquely from a rear side of the first mirror, and the second mirror has first and second surfaces which form different angles with the first mirror. The first surface is translucent so that light is reflected from and transmitted through it, while the second surface reflects the light which is transmitted through the first surface. The first surface reflects light towards a distance measuring element, while the second surface reflects light towards a light measuring element so that the mechanical arrangement of the distance and light measuring device is simplified.

Abstract: An automatic focus detecting device for a camera in which a contrast signal is produced which is made independent of variations and brightness of the object being viewed and of vibrations of the camera by utilizing an out-of-focus image on an average illumination detecting photoelectric element. The average illumination detecting photoelectric element is disposed in a plane perpendicular to the optical axis of an optical image of the camera. A pulse generator produces an output clock pulse signal having a frequency which is controlled by the output signal from the average illumination detecting photoelectric element. A self-scanning type photoelectric element array is scanned with this variable frequency clock pulse train wherein the frequency of the clock pulses is increased when the brightness of the object being viewed increases to thereby increase the dynamic range of the device.

Abstract: A focus position indicating device for a camera including an array of electrically activatable display elements such as light emitting diodes or liquid crystal elements, the number of which are activated being dependent upon the state of focusing. A drive contrast signal is converted into a digital signal and compared with the count output of a continuously-cycling digital counter. The output of the counter is also decoded into a set of signals one of which is activated for each possible state of the counter output. The decoder output signals are gated by the output of a comparator circuit with the outputs of the gates connected to drive the display elements.

Abstract: A multi-layer flexible printed circuit board assembly, having at least two flexible printed circuit boards with electrical conductive layers piled one on another. The conductive layers face in the same direction and a portion of the lower flexible printed circuit board is not covered with the upper flexible printed circuit board. Hence, some of the lead wires of an electronic component can be connected to the electrical conductive layer of the upper flexible printed circuit board, and the remaining lead wires can be connected to said electrical conductive layer of the lower flexible printed circuit board. The portion of the lower flexible printed circuit board which is not covered by the upper flexible printed circuit board is raised so that the surface of a copper foil layer on the upper flexible printed circuit board is substantially flush with the surface of a copper foil layer on the lower flexible printed circuit board.

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: 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: The shutter curtain surface(s) in a single lens reflex camera on the side facing the lens is roughened, as by sand blasting, to provide more uniform light diffusion and reflective scattering characteristics, whereby the output of a light sensing element disposed in the mirror box facing the shutter provides a more accurate measure of the integrated or averaged light intensity distribution over the entire picture or viewing frame.

Abstract: A single lens reflex camera has behind its objective a main mirror for reflecting light up to the viewfinder. This main mirror has a semitransparent portion through which part of the light which has traveled through the objective passes. Behind the semitransparent portion of the main mirror is an auxiliary mirror for receiving the light which has passed through the semitransparent portion of the main mirror and for reflecting this light along a predetermined path. A photosensitive device is situated along the latter path to receive the light reflected by the auxiliary mirror and to participate in the measurement thereof. The main mirror has at its semitransparent portion a front surface from which part of the light which has traveled through the objective is reflected up to the viewfinder and a rear surface beyond which part of the light travels to the auxiliary mirror.

Abstract: A light meter for a SLR camera implements both initial exposure time display and automatic exposure time control using a single light sensing element 8. The reflex mirror 3is formed as a beam splitter or half-mirror. When lowered, some of the viewfinder light passes through the mirror and is reflected onto the sensing face of the element 8 by the shutter curtains 9 or 10 to enable the time display function. When the mirror is raised and the lens diaphragm 2 reduced, the light is again reflected from the curtains and/or film surface 11 onto the sensing element face to enable the time control function.A hinged shield 13 may be provided to block light from entering the camera box 12 via the rangefinder lens 7 when the mirror 3 is raised, and dual sensing elements 8, 8' may be employed together with an additional reflecting mirror 15 and an angled or concave shield 13 ' to effect a uniform vertical light distribution sensitivity in both the display and control modes.

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 exposure display device for a single lens reflex camera including light display elements for displaying either shutter speed or diaphragm value is disclosed. Nominal values representing either shutter speed or diaphragm value are marked on a glass plate disposed in the vicinity of the focusing plate of the camera's viewfinder. A first display section, comprising a first set of light display elements aligned with (and, if desired, located inbetween) the nominal values, creates a first exposure component (e.g. diaphragm value or shutter speed) display whose value is related to predetermined exposure conditions, such as object brightness, film sensitivity and the other exposure component (e.g. shutter speed or diaphragm value). A second display section, comprising a second set of light display elements, also aligned with the nominal values, creates a second display of the exposure component chosen to be displayed.

Abstract: A single lens reflex camera system includes multiple replaceable mirrors, each designed to accomplish a specified function for different conditions of photography.

Abstract: A through the lens (TTL) photometric function is provided by apparatus built into a viewfinder system for a single lens reflex (SLR) camera. As to the viewfinder function, an optical path is defined between the SLR focusing screen and a viewfinder eyepiece. A first prism, forming part of the optical path, has a plurality of faces, two of which serve to internally reflect light entering the prism so that the light emerging from the prism has been twice reflected. As to the photometric function, at least one separate optical path is defined for light emerging from the first prism at a peripheral position outside the finder field. In each separate optical path there is a second prism and a light receiving element with the second prism being arranged between the first prism and the light receiving element.

Abstract: A photometric device for use in a single lens reflex camera comprising a photometric optical system and a light receiving element disposed behind a pentaprism is disclosed. The light receiving element is disposed at a position where the image of a subject, imaged on a focusing glass plate by the photographing lens, is refocused by the photometric lenses. The light receiving area of the light receiving element is sized so that only a portion of the light refocused by the photometric lenses is received to provide a photometric operation that gives priority to a portion of the subject image.