Abstract: A flash illumination device is removably mounted on the body of an accompanying camera. Electric adjusting means set the diaphragm of the camera. A signal system produces a signal corresponding to a prescribed diaphragm setting and transfers the signal through a shoe attached to the camera body or through other electric connecting means. When the flash illumination device is connected to the camera body, the signal system provides an electrical signal which causes the adjusting means automatically to set the diaphragm.

Abstract: An interchangeable-lens camera is usable with a flash unit which stops the flash on the basis of the object distance and transmits a signal corresponding to a required aperture value. The camera includes a diaphragm control that responds to the light passing through the maximum aperture of the interchangeable lens and corrects for a particular maximum aperture. A selector causes the diaphragm control to respond either to the light or the signal transmitted by the flash and a switch aborts the maximum aperture connection during flash photography.

Abstract: In the disclosed light measuring system, light coming from a photographic lens is measured through a momentarily closed diaphragm and memorized to control the diaphragm during a subsequent exposure.

Abstract: In the disclosed solid-state diaphragm device, a liquid crystal cell is driven by a matrix driving system. Electrodes of a set on one plate of the cell are arranged in concentric circular relation to each other, while electrodes of another set on the other plate are arranged in radial relation. Related ones of the latter electrodes are connected with one another at their outer or inner peripheral portions to the matrix driving system.

Abstract: An exposure control apparatus including an electrically operated optical diaphragm. The apparatus is provided with means for detecting a quantity of light coming from an object to be photographed during an exposure control cycle thereof. The detecting means is connected to the electrically operated optical diaphragm device in accordance with an output signal of the detecting means during the exposure control cycle.

Abstract: The present invention relates to a diaphragm device for a camera, particularly making use of the property of matter in such a manner that the light permeable characteristics of the matter is changed by applying the control signal to the matter so as to form a light shading part and a light permeable part in order to control aperture. In case of the above-mentioned diaphragm device, a matter having property is sandwiched between the first electrode member consisting of a plural number of the electrode plates and the second electrode member, whereby the control signal is selectively applied to certain determined electrode plates in accordance with the aperture signal in such a manner that only the part of the matter facing to the selected electrode plates assumes the light shading state so as to form the light shading part and the light permeable part so that the aperture is controlled by means of the ratio of the area of the light shading part to that of the light permeable part.

Abstract: A focusing screen device for use in a photographic camera or other suitable optical instrument includes a light refracting structure having a number of sets of light refracting surfaces. Each set of surfaces provides a different light refracting direction than that of the other sets. A light control assembly including an electro-optical element controls the passage of light through each surface of each set. The focusing condition of the optical system of the camera then is perceived by observing whether or not an object image changes its position, as a whole or in part, after light from the object passes through the device. For example, the position of the image may change continuously or periodically as a split line scans the image. Accordingly, the observer is able to recognize the focusing condition of the optical system with extreme clarity.

Abstract: A display device comprising a first semiconductor stripe and a second stripe of composite structure in which a great number of successive areas alternate between a semiconductor material having different type with respect to that of the first stripe and an insulating material or materials and which is positioned in side-by-side contact relation to the first stripe to establish P-N junctions. A resistor stripe connected lengthwise to the second stripe so that a voltage proportional to a value of information which is desired to be displayed is applied across a third stripe when first stripe is negatively biased, a corresponding number of successive semiconductor areas in the second stripe are caused to emit visible light, giving a viewer the impression of a continuous luminous stripe having a length representative of the information value.

Abstract: A stop device of the type using a physical property member which is arranged to have its light transmission factor variable and to form a light shielding part and a light transmitting part for effecting adjustment of an aperture value by adjusting the area of the light transmitting part. The area of the light transmitting part for each stopping step of the aperture is determined in relation to the light shielding part and the light transmission factor of the light transmitting part to obtain an effective T number.

Abstract: A charge circuit for secondary batteries. The charge circuit encompasses a control circuit having as a power source accumulators chargeable with the current resulting from the electromotive force of a plural number of solar batteries built in a camera. The plural number of the solar batteries are distributed at a plural number of portions on the exterior of the camera. The plural number of the solar batteries are connected in series or parallel or, in accordance with necessity, a serial-parallel connection change-over of the solar batteries is carried out. Circuits for comparing the level at both terminals of each solar battery and for short-circuiting the terminal in accordance with the result of the comparison are provided.

Abstract: In a slit exposure shutter having leading and trailing blades driven to run down to make an exposure and to return to their initial positions by an electromagnetic drive source, this source is provided with electromagnetically operated latch means for holding the leading and trailing blades in either one of the terminal ends of running down and returning movement thereof. Another feature is that the above-described latch means is constructed by utilizing the magnetic attraction force of at least one of the stationary and movable electromagnetic members of the drive source.

Abstract: The present invention relates to an aperture stop-down confirmation device for a camera. So far, in order to carry out the aperture stop-down operation for confirming the depth of focus before photographing in the case of a camera having a mechanical diaphragm device, it is necessary to drive the diaphragm member against the strength of the charge spring of the diaphragm device so that considerable strength is needed for carrying out the diaphragm closing, which is inconvenient. In accordance with the present invention, a diaphragm device whose aperture is controlled by means of an electrical signal such as a diaphragm device making use of a property of matter is so designed that the light admitting part and the light shading part are constituted by varying the light transmittance.

Abstract: A flash illumination device is removably mounted on the body of an accompanying camera. Electric adjusting means set the diaphragm of the camera. A signal system produces a signal corresponding to a prescribed diaphragm setting and transfers the signal through a shoe attached to the camera body or through other electric connecting means. When the flash illumination device is connected to the camera body, the signal system provides an electrical signal which causes the adjusting means automatically to set the diaphragm.

Abstract: In the slit exposure shutter disclosed, front and rear shutter blades carry permanent magnets along a passage of electromagnets which are excited to repel the permanent magnets and cause the blades to float in the gaps of the electromagnets.

Abstract: In a camera provided with an electromagnetic drive source when energized producing an electromagnetic force by which the shutter is driven to move, the above-described electromagnetic force of drive source is used only as the power of driving the shutter, while an electromagnetic device which is controlled by a shutter closing signal is provided, so that an initiation of returning movement of the mirror and automatic diaphragm and of lock releasing operation of the film transporting mechanism is controlled by said electromagnetic device.

Abstract: A slit exposure shutter having the front and rear screens thereof respectively arranged to be driven by a source of an electromagnetic driving force is provided with a minimum slit width insuring means which prevents uneven exposure resulting from difference in travelling speed between the front and rear shutter screens during a high speed shutter operation and particularly prevents a total absence of the slit, the shutter is also provided with a nullifying means which nullifies the insuring means when the shutter screens are on their return travels.

Abstract: A liquid crystal cell of elongated shape adapted to be arranged at one side of the field of view of the camera finder has a plurality of opposing of transparent electrodes on opposite sides of a liquid crystal layer which are aligned to each other in a matrix form, whereby the necessary number of leads is reduced. In order for the liquid crystal layer to present an indication in a selected area, or areas, an alternating voltage is applied across the correspondingly aligned electrodes, while still preventing the above-identified alternating voltage to appear at two or more electrodes in one set simultaneously even when light is blocked in the two separated areas of the liquid crystal layer. In other words, the number of those of the plurality of electrodes in set to which the alternating voltage is applied at a time depending upon the exposure value is limited always to only one even when two separated areas are selected for light shuttering at a time.

Abstract: By providing a liquid crystal cell nearly at the position of the clear vision of the view finder optical system together with a means for masking the display part of the liquid crystal cell the noise appearing on the boundary between the display part and the object view field is eliminated while the invasion of dusts is avoided, whereby further by means of the liquid crystal cell the alarm for the improper exposure, the alarm of the consumption of the power source battery and so on are displayed besides the photographic informations.

Abstract: The present invention relates to a liquid crystal cell having a plural number of electrode pairs arranged on both sides of the liquid crystal matter so as to be opposed to each other, being characterized in that a pulse wave generating device for generating the first pulse wave with smaller amplitude than the threshold value for lighting the liquid crystal and the second pulse wave with larger amplitude than the threshold value for lighting the liquid crystal in reversed phase to each other and a gate device for selectively applying the outputs of the pulse wave generating device to each electrode of the liquid crystal cell in accordance with the input signal are provided. Thus, only the voltage between the selecting electrodes is higher than the threshold value. An input change over device is provided so as to change over the input signal group in a time dividing way in such a manner that a plural number of dots can be displayed visually at the same time. As a result, the wiring is simplified.

Abstract: In the slit shutter disclosed, an actuator transmits the rotational force of an electromagnetic drive arrangement to move shutter blades through opening and closing cycles. A spring arrangement for engaging the actuating means serves to aid the shutter movement at the beginning of the cycle and retard the shutter movement at the end of each cycle while the spring arrangement is energized during its retarding action. According to an embodiment of the invention, the spring arrangement encounters an arm of the actuator at the end of each cycle, absorbs the arm movement during the retardation, and uses the energization to aid the movement at the start of the next cycle. The spring arrangement again encounters the arm at the end of the next cycle.