Abstract: A discharge light having a light emitting tube (1) encapsulates a discharging medium, an inner electrode (2) disposed in the light emitting tube, and an outer electrode unit (4) fixed to the outside of the light emitting tube. The outer electrode unit has at least a plurality of outer electrodes (4b) arranged intermittently in the axial direction of the tube and having a part abutting on the outer wall face of the light emitting tube, and a part (4c) engaging with the light emitting tube while coupling the outer electrodes thereof integrally, wherein the engaging part clamps the light emitting tube at a part thereof thus holding the outer electrode unit around the light emitting tube. The light emitting tube is lighted by applying a voltage between the inner electrode and the outer electrode. The outer electrode can be fixed readily to the light emitting tube and the plurality of outer electrodes can be held against the light emitting tube with high accuracy.

Abstract: A discharge light comprising a light emitting tube (1) encapsulating a discharging medium, an inner electrode (2) disposed in the light emitting tube, and an outer electrode unit (4) fixed to the outside of the light emitting tube. The outer electrode unit comprises a plurality of outer electrodes (4b) arranged intermittently in the axial direction of the tube and having a part abutting on the outer wall face of the light emitting tube, and a part (4c) engaging with the light emitting tube while coupling the outer electrodes thereof integrally, wherein the engaging part clamps the light emitting tube at a part thereof thus holding the outer electrode unit around the light emitting tube. The light emitting tube is lighted by applying a voltage between the inner electrode and the outer electrode. The outer electrode can be fixed readily to the light emitting tube and the plurality of outer electrodes can be held against the light emitting tube with high accuracy.

Abstract: An electric discharge tube withstands a large electric input, and has a small size. This discharge tube provides a small photographic strobe device and a small photographic camera. The discharge tube includes a glass bulb having a wall thickness ranging from 0.2 to 0.6 mm and filled with rare gas, a pair of main electrodes provided at both ends of the glass bulb, respectively, a trigger electrode formed on the outer surface of the glass bulb, and a film of silicon dioxide having a thickness ranging from 0.05 to 0.11 &mgr;m formed inside of the glass bulb. An electric power not larger than 0.90 Ws/mm3 with respect to the inner volume of the glass bulb is applied between the main electrodes.

Abstract: An illuminator requiring no prism sheet and having a high light efficiency and a liquid crystal display comprising the same. The illuminator has a plurality of groove groups 2 extending in a parallel to one side face 10, close to which a light source is disposed, each group including one or more grooves, and a flat face 16 bridging the groups 2-1 and 2-2, in the bottom surface 9. The depth of the grooves gradually increases from one side face 10 toward the other side face; or the depth is fixed constant from side face 10 to the proximity of area M and then gradually increases towards the other side face. The pitch p among the plurality of groove groups is fixed constant from side face 10 the other side face; or the pitch gradually decreases from side face 10 towards the proximity area, and the it is fixed constant to the other side face. The present invention implements the objective through combination of the groove depth and the pitch of the groove groups.

Abstract: In a discharge lamp, at least one of two main electrodes disposed at both ends of the discharge lamp includes one main electrode that comprises a sintered metal member having a slope with respect to another main electrode. A tip of the slope is positioned within a space covered by a trigger electrode coated on an outer surface of the discharge lamp in a limited area with respect to the entire circumference of a bulb of the lamp. This structure allows the discharge lamp to emit light at a stable level constantly. An electronic flash device using this discharge lamp can emit the light precisely.

Abstract: In a flash apparatus capable of making high-speed repeating light emission, a self-maintaining switch element provided for various purposes is prevented from erroneously operating due to the high-speed repeating light emission, by providing a circuit element which reverse-biases a control electrode of the self-maintaining switch element.

Abstract: A flash apparatus capable of varying the emission angle according to the present invention is characterized in that a light controller provided in front of a reflector for diffusing or condensing supplied light is configured to comprise a diffusion controlling portion having light diffusive action only with respect to a longitudinal direction of a bar-like light source and a condensation controlling portion having condensing action to omnidirectionally condense supplied light. By this, the flash apparatus capable of varying the emission angle can control and restrict prism action at the light controller by diffusing light emitted from the bar-like light source in respect to the longitudinal direction of the bar-like light source even when the bar-like light source and the light controller are close to each other.

Abstract: By more widely diffusing light from a rod light source, particularly in the direction of the length of the rod light source than conventional strobe lights and image recorders, a strobe light of the present invention and an image recorder containing the strobe light provide luminous intensity distribution characteristics including a light emitting angle large enough to cover, for example, landscape images and the angle of coverage of imaging lenses with a short focal length. This allows the light emitting angle in the direction of the length of the rod light source to increase during wide-angle imaging, with little variation in the luminous intensity distribution characteristics in the direction at right angles to the direction of the length of the rod light source, as compared with known-arrangement strobe lights.

Abstract: An emission angle variable flash apparatus of the invention alters an angular aperture to be formed by side reflection plates disposed oppositely to both side surfaces of a reflector in linkage with a change of a distance between a Xe tube and a reflector on their optical axis, thereby enhancing the efficiency of utilization of flash from a light source and expanding a variable range of an emission angle in the horizontal direction. As a result, the emission angle variable flash apparatus of the invention is made smaller in size than in the prior art.

Abstract: A cold cathode fluorescent discharge tube is provided having, as an anode standing for one of discharge electrodes, a mercury discharge structure comprising a metal sintered body formed by sintering powder of a high melting point metal such as titanium, with mercury combined with the metal sintered body. The mercury discharge structure is so formed as to contain a large amount of mercury and is therefore permitted to have a compact shape in order to obtain a requisite amount of mercury. The cold cathode fluorescent discharge tube permits a sufficient amount of mercury to be sealingly incorporated in the interior of the tube without decreasing the ratio of the effective luminescent length to the total length, having suitability to diameter reduction, and can be produced at low cost.

Abstract: A cold cathode fluorescent discharge tube is provided having, as an anode standing for one of discharge electrodes, a mercury discharge structure comprising a metal sintered body formed by sintering powder of a high melting point metal such as titanium, with mercury combined with the metal sintered body. The mercury discharge structure is so formed as to contain large amount of mercury and is therefore permitted to have a compact shape in order to obtain a requisite amount of mercury. The cold cathode fluorescent discharge tube permits a sufficient amount of mercury to be sealingly incorporated in the interior of the tube without decreasing the ratio of the effective luminescent length to the total length, having suitability to diameter reduction, and can be produced at low cost.

Abstract: An electronic flash unit being effective in emitting light repeatedly at high speed by boosting an applying voltage between main electrodes of a flash discharge tube twice or more as much as a charged voltage in a main capacitor connected parallel to a high voltage DC power source, wherein the electronic flash device has a plurality of boosting capacitors connected with the flash discharge tube through plural second control switches respectively and a common circuit including an insulated gate bipolar transistor IGBT, the main capacitor and a first control switch for selective excitations, and also connected with a primary winding of a trigger transformer via a trigger capacitor, a diode and so on for charges during being un-excited, and wherein the electronic flash device has a switch control device for selectively turning on one of the plural second switches and for simultaneously turning on the first switch so as to supply a high voltage to the flash discharge tube being combined with the charged voltages

Abstract: A strobo device in accordance with the present invention is provided with an insulated gate bipolar transistor connected to a flash discharge tube in series and a step-up capacitor to step up a voltage between the main electrodes of the flash discharge tube in the luminous operation. The step-up capacitor is connected so that a terminal on the side connected to a cathode of the flash discharge tube can have a high potential and the step-up capacitor is also connected so as to be charged by a current flowing through the flash discharge tube, which is not flashing. Thus the device realizes a rapid charging of the step-up capacitor. In this way a high voltage, at least more than twice as high as the charged voltage of the main capacitor, can be applied between the main electrodes of the flash discharge tube in the luminous operation, resulting in preventing flash failures during the repeating high-speed luminous emissions.

Abstract: An I.G.B.T. (Insulated Gate Bipolar Transistor) driven electronic flash unit includes a control switch for controlling an off-operation of the I.G.B.T. The control switch has a first terminal for receiving a light-emission stopping command of a very short pulse width, a second terminal supplied with a collector electrode voltage of the I.G.B.T. connected in series with a flash tube, third and fourth terminals respectively connected with gate and emitter electrodes of the I.G.B.T., which short-circuits the third and fourth terminals upon receiving the light-emission stopping command at the first terminal, and maintains the short-circuit operation as long as it receives the collector electrode voltage of the I.G.B.T. at the second terminal.

Abstract: In an electronic flash unit, a voltage applying device is provided to apply a predetermined voltage to the gate of an insulated gate bipolar transistor (IGBT), connected in series with a flash tube, for controlling the light-emission operation of the flash tube. The voltage applying device produces the predetermined voltage in response to the start of the operation of a DC high voltage power source. Thus, the voltage applying device applies a driving voltage to the gate of the IGBT without responding to a light-emission command signal. The IGBT enters a conduction standby state in response to the start of the operation of the DC high voltage power source, and is placed in a fully `on` state when a trigger circuit is operated by the light-emission command signal. The driving voltage can be applied to the gate in a very simple arrangement which does not require to respond to the trigger signal.

Abstract: An electric flash apparatus of the present invention is actuated to emit light by application of a trigger signal issues by a trigger circuit (5) after a power transistor (4), such as, an I.G.B.T. (insulated gate bipolar transistor) connected in series with a flash tube (3), is certainly turned to sufficient ON state.

Abstract: An electric flash apparatus of the present invention has an Insulated Gate Bipolar Transistor (I.G.B.T.) for controlling the light emission actuation of the strobe tube (Xe), which is connected to the strobe tube in series, a switching element (11) for supplying a driving signal to the I.G.B.T. from a main capacitor (C.sub.M), and a gate circuit (14) for controlling actuation of the switching element (11), which is connected across both ends of the strobe tube (Xe), and is actuated by a switch circuit (17) for actuating a trigger circuit (20). And the actuation of the switching element (11) is kept by turning on of the I.G.B.T.

Abstract: A drive device for a lens barrel and a diaphragm shutter is disclosed. The drive device of this invention comprises a stepping motor including a stator and rotors. The stator is constituted by a plurality of stator members disposed around a lens barrel, each having a bifurcate portion around which a conductor is wound, and the bifurcate portions are disposed in face-to-face relationship with each other with a predetermined space being interposed therebetween. The rotors are respectively disposed in the predetermined spaces. The driving forces of the rotors are independently transmitted at least to the lens barrel including a photographic lens element and to a diaphragm shutter.

Abstract: An automatic film winding system comprising in combination, a mechanical film winding or transport system including an electric motor and an optical film-advance sensing system comprising a light source and a light sensor for sensing the length of the film advanced in terms of one or more perforations of the film passed past a predetermined point. In response to the depression of a shutter button, a power supply is automatically connected to the light sensor and then to the electric motor and the light source when one exposure operation has been completed so that the film is advanced or wound. When a predetermined number of perforations has passed past the predetermined point and sensed by the optical sensing system; that is, after the film has been advanced by a predetermined length, the power supply is disconnected from the light sensor, the electric motor and the light source.