Abstract: A thermoelectric power generation system 20 includes a heat exchanger 1 having double tubes which are an inner tube 1a and an outer tube 1b, and a thermoelectric power generation module 2 mounted between the inner tube and the outer tube. The thermoelectric power generation module generates thermoelectric power using a temperature difference between a medium inside the inner tube and a medium outside the outer tube, and a highly thermal conductive elastic sheet 3a, 3b is mounted between the thermoelectric power generation module and the inner tube and/or the outer tube in close contact therewith.

Abstract: A zoom optical system is composed of a positive focusing lens group, a negative variating lens group, a negative compensating lens group and a positive rear fixed lens group. A rotating grooved cam moves the variating lens group and the compensating lens group in a given relation to each other along the optical axis in the normal focusing range. The focusing lens group is moved along the optical axis normal range for focusing. The variating lens group is kept stationary on the optical axis while the compensating lens group is moved along the optical axis during close-range focusing.

Abstract: A motion picture camera which can use a cartridge for film having a sound track includes sound recording means and a mechanism which actuates and releases the sound recording means to an operative state and to an inoperative state, respectively, in response to an actuation and a release of a shutter release member. All such parts which are needed to engage a film are arranged in a cartridge chamber defined in the camera housing so that the operator enables to readily insert a cartridge into the chamber so long as the sound recording means are set to their inoperative position.

Abstract: In a diaphragm device for use in an optical instrument such as a camera and having two or more diaphragm blades movable across an imaging path of rays and arranged in axially displaced relation from each other to define a common aperture of variable size, there is provided means formed in a portion of at least one of the diaphragm blades to substantially either eliminate or reduce the axial displacement between the diaphragm blades at a relatively small aperture region, whereby the distribution of light energy is made uniform over the entire area of the image.

Abstract: A photographic camera in which a film cartridge, housing a photographing film having a recording belt capable of recording sound signal, can be loaded, wherein for the purpose of effecting the recording of sound signal simultaneously with photographing a sound signal recording head and a constant speed film running mechanism are provided at the sound signal recording part being separated from an intermittent film transport mechanism for running the above mentioned film with a constant speed.

Abstract: A zoom lens structure for use with an optical instrument comprises a zooming optical system movable along the optical axis thereof and including a magnifying system and a correcting system; support frames for holding the zooming optical system; a plurality of guide shafts fitted in the support frames of the zooming optical system to cause sliding of the support frames; a frame member for holding the guide shafts at the opposite ends thereof and surrounding the zooming optical system; a fucusing optical system; a holder frame for permitting the focusing optical system to be moved along the optical axis independently of the zooming optical system; and a mechanism using a cam to drive the holder frame. Within the frame member surrounding the zooming optical system, a beam splitter for splitting an object light beam to derive a viewfinder light beam is interposed between the portion of the frame member remote from an object to be photographed and the zooming system.

Abstract: The present invention refers to a motion picture camera which is characterized in that respectively on the driving shaft to be rotated by means of a driving power from the driving motor and on the shutter shaft to be rotated by means of a rotating power of the above mentioned driving shaft elliptical gears in mutual engagement with each other are provided in such a manner that the ratio of the angular speed to be communicated between the driving shaft and the shutter shaft is continuously increased and decreased while on the above mentioned shutter shaft a non-circular cam to reciprocate the claw for feeding film is provided in such a manner that while the shutter blade is opened the shutter shaft rotates slowly and further the claw for feeding film stops feeding film whereby the effective proper opening angle of the shutter blade is changed largely by means of the above mentioned pair of elliptical gears and the non-circular cam.

Abstract: A film gate formed as one integral unit by molding a black synthetic resin material includes a film gate portion, a recess for receiving a film driving member for reciprocal movement therein, film guide walls, positioning means and protective walls to protect resilient side pressure members from damage from careless loading of a film magazine. The positioning means may be used as reference position to secure the gate unit to a fixed frame of a motion picture apparatus. The side pressure members are formed as extensions of a holding member that also applies resilient force to the film driving member near the root of its film-advancing pawl.

Abstract: An information displaying apparatus includes, bundles of optical fibers with their ends coplanar and disposed in line. A movable masking member imposes information on the light input to the fiber array. At the output end, information markings are selectively illuminated or otherwise luminously designated to display various kinds of information. Displaying means may be disposed within a view finder or on the outer casing of a camera. An artificial light source operates to provide light through the masking member and may be switched on manually or automatically when needed for information display.