Abstract: A focusing screen provided with a plurality of cylindrical lenses adjacent to one another is disclosed. The adjacent two of the cylindrical lenses have individual characteristics to shift between respective areas an image of an object in opposite directions when the object is out of focus. For this reason, when in an out-of-focus condition, the amount of the slided image along a boundary line between the areas is doubled, thus permitting the operator to perform a focusing operation with high accuracy.

Abstract: A view finder for a camera includes an eye piece and an optical system having an optical axis to direct light from a certain view field towards the eye piece. A reflecting device directs light from outside the view field through the optical system at a given angle relative to the optical axis, and a sub-prism is arranged relative to the optical system to direct the light from outside the view field toward the eye piece after the light passes through the optical system. The sub-prism has a light incident plane, a light reflecting plane and a light emitting plane all of which are arranged so that after the light from outside the view field passes through the optical system, it enters the sub-prism through the light incident plane. The light is thereafter reflected from the reflecting plane so that it leaves the sub-prism from the light emitting plane.

Abstract: A view finder for a single-lens reflex camera has a notch formed in the light exit face of a view finder prism outside of the area through which photographic light rays are passing. At the notch, a reflection member guides rays of light representing photographic data and passing through the inside of the view finder prism toward an eyepiece.

Abstract: A camera having a holographic indicator in which a reconstructed image of hologram and an image of an object formed by an image forming optical system are formed on the same plane, so that the reconstructed image and the object's image can be observed at the same diopter through a common observation optical system.

Abstract: A camera wherein a front housing which contains a photographing optical system, an exposure device, etc. is connected by a foldable connecting device such as a bellows or the like to a rear housing which contains a photosensitive material to be exposed to light, a view finder optical system, etc. During photographing, the foldable connecting device is stretched to adjust the distance between the front and rear housings to a distance suitable for photographing. When the camera is not in use, the connecting device is contracted to being the front and rear housings very close to each other. An electrical wiring arrangement of a flexible material is either provided on the surface of the bellows or formed together with the bellows as an integral part of the bellows when it is formed in such a way as to be stretchable and contractable together with the bellows, the wiring service to electrically connect the components disposed in the front housing to those disposed in the rear housing.

Abstract: A data printing device for use in a photographic camera includes an electronic clock for providing time and date data to be printed in digital form on the associated film in the camera. In one embodiment, the data are grouped into two parts which are printed in time-displaced relation to each other on a common picture frame, while the data are prevented from changing during the printing operation, as time passes on. The display of data is effected only when printing is performed, or when required or desired values of time and/or date are set in the electronic clock, thereby the consumption of electrical energy of a common battery of the exposure control apparatus in the camera is minimized.

Abstract: A data recording camera capable of recording a data image on film as well as observing the data image through the view finder is disclosed. A beam splitter directs the light beam coming from the data to the film and view finder. The inner surface reflector of the beam splitter forms a ghost beam which forms a ghost image of the data on the film. The ghost image of the data is removed by a polarization filter (polar screen), wedge prism or thick glass plate.

Abstract: A photographic data recording device for a camera for photographically recording some data on film together with a photographic image. The device includes a capacitor, a charging circuit for the capacitor which responds to the release of the shutter for commencing charging and an electronic flash device operating in response to the capacitor discharge to illuminate the data. A control device automatically causes the capacitor to discharge electricity to allow the electronic flash device to emit a flash when the charge of the capacitor reaches a preset level of potential and which prevents the capacitor from discharging when the charge is below the preset level of potential. A display lamp may be utilized to indicate when the charged voltage of the capacitor reaches a preset level.

Abstract: The present invention relates to a device for measuring light incident on an image-forming optical system, making use of a plural number of diffraction elements. The plural number of the diffraction elements are respectively provided in the optical path of the image-forming optical system. Further the plural number of the diffraction elements respectively have a certain predetermined area. The plural number of the diffraction elements, seen along the direction of the optical axis of the image-forming optical system, are substantially only partially overlapped with respect to each other. The light beam incident on a diffraction element is divided into a non-diffracted light beam and a diffracted light beam. Thus, the diffracted light beam is directed toward the light detecting means so as to be measured while the non-diffracted light beam advances along the above mentioned optical axis.

Abstract: A camera having a holographic indicator in which a reconstructed image of hologram and an image of an object formed by an image forming optical system are formed on the same plane, so that the reconstructed image and the object's image can be observed at the same diopter through a common observation optical system.

Abstract: In a finder optic system having the structure in which a tiltable mirror, in its reflecting position, reflects light entering through the camera objective upward onto a focusing screen where an image of the object to be photographed is formed and light from the image is radiated upward through the condenser lens and a pentaprism into an eyepiece, a light meter arrangement in accordance with an embodiment of the invention comprises a single photo-cell and a glass plate provided with an angular surface formed therein for acceptance of the photo-cell.

Abstract: In a reflex camera having a penta prism positioned in the view-finder thereof, there is provided a glass member having a reflactive index equal to or larger than that of the penta prism and positioned in intimately contacting relation with the exit surface of said penta prism to utilize that portion of a view-finder image forming light beam which is directed to the exit surface of said penta prism after successive reflection from the two roof surfaces, the front reflection surface and again the roof surfaces of the penta prism such light beam portion would be otherwise subject to the total reflection from the exit surface in vain in measuring the light at a central portion of the view-finder image as well as at any portions outside thereof. In this way it being made possible to operate the camera selectively in a spot-metering mode or overall field of view light metering mode by the use of a single light value sensing means without causing the reduction of quality of the view-finder image.

Abstract: In the disclosed single lens reflex camera a focusing screen presents exposure information in addition to an image of the scene to be photographed. The image area of the screen is surrounded by walls protruding upward from and integral with the screen to prevent dust from entering the image area and to space the viewfinder lens from the screen in a dust tight manner along all or most of the periphery. Also disclosed is a pointer in a second area adjacent to one wall outside the image area which indicates information on a scale or a sliding plate.A fresnel lens, angled edge, or other means formed on the upper and/or lower side of the screen directs light to both the image area and the second area.

Abstract: The present invention relates to a data printing device suited to be built in a compact camera, the device is designed so that optical fibers are provided between the data carrier comprising data figures and the photosensitive film in such a manner that the data light is transmitted through the optical fibers so as to form an image of the data figures on the film plane by means of the image forming lens.

Abstract: The present invention relates to a device for measuring light incident on an image forming optical system, making use of a plural number of the diffraction element. The plural number of the diffraction elements are respectively provided in the optical path of the image forming optical system. Further the plural number of the diffraction elements respectively present a certain predetermined area. The plural number of the diffraction elements, seen along the direction of the optical axis of the image forming optical system, are substantially only partially overlapped with respect to each other. The light beam incident on a diffraction element is divided into a non diffracted light beam and a diffracted light beam. Thus diffracted light beam is directed toward the light detecting means so as to be measured while the non diffracted light beam advances along the above mentioned optical axis.

Abstract: A data recording device for a single reflex camera has a demountable view finder in which a data signal from a source is guided by optical means along a data recording optical path and divided, for viewing and entering the camera.

Abstract: A view finder system for a single lens reflex camera which provides in the field of the finder an image of a photographic information indicator such as a distance adjusting ring, diaphragm adjusting ring and the like movably mounted in the lens barrel which is connected to the camera body. The view finder includes a pentagonal roof prism in combination with supplementary optical means optically connected thereto, said supplementary optical means comprising a sub-prism having an exit face cemented to the front non-reflecting face of the pentagonal roof prism, an entrance face and a reflecting face, and a mirror element spaced apart from the sub-prism. The mirror element is arranged above the sub-prism to face down optically both the indicator and the sub-prism, so that a light beam from the indicator is reflected by the mirror element to the sub-prism and thereby directed through the pentagonal roof prism to provide an image of the indicator in the field of finder.

Abstract: A light measuring device for a single lens reflex camera wherein a reflection member having a slant surface is provided at the rear of an exit plane of a pentagonal roof prism and locating to be outside of the viewfinder light path, and the effect by undesired incident light is eliminated by a mirror formed by the slant surface placed in front of the light receiving element or photosensitive device, which light once enters into the pentagonal prism from the ocular lens and is reflected at the bottom surface thus again comes out of the surface of the pentagonal prism facing the ocular lens to proceed toward the photosensitive device.

Abstract: An object image is formed on a screen by an objective lens. The light beam from the object image formed on the screen is guided in a direction to an eye piece by a pentagonal roof prism. Only one light measuring means is provided facing an upper part of the exit face of the pentagonal roof prism. Therefore, the light beam from the screen passing through the upper part of the pentagonal roof prism impinges into the light measuring means. Also the light beam from the screen passing through both left and right end parts of the exit face of the pentagonal roof prism is directed onto the light-measuring means through a reflective plane. A shutter means is provided at least for one of the luminous flux from the upper part of the pentagonal roof prism and the luminous flux from the both left and right end parts. The light measurement distribution in an object scene may be varied by the shutter means.

Abstract: The finder device forms the images of a plural number of photographing information indication bodies, provided on the exterior of the camera in a row extending in a direction other than parallel to one side edge of the focussing screen of the camera, in the neighborhood of the rectangular image of the focussing screen to extend in a row in a direction parallel to such side edge of the focussing screen and closely adjacent this side.