Abstract: A range-finding device includes: a light emitting unit that continuously emits measurement light to be used for distance measurement toward a measurement target object; a light-receiving unit that receives reflected light reflected by the measurement target object; a calculation unit that repeatedly calculates a distance to the measurement target object over predetermined time intervals by using the reflected light; a display unit at which an update of the distance is displayed each time the distance is calculated by the calculation unit; and a display update control unit that prohibits the update of the distance on display at the display unit and sustains the display of the previously calculated distance at the display unit according to a change in the most recently calculated distance calculated most recently by the calculation unit relative to the previously calculated distance having been calculated previously by the calculation unit.

Abstract: A range-finding device includes: a light emitting unit that continuously emits measurement light to be used for distance measurement toward a measurement target object; a light-receiving unit that receives reflected light reflected by the measurement target object; a calculation unit that repeatedly calculates a distance to the measurement target object over predetermined time intervals by using the reflected light; a display unit at which an update of the distance is displayed each time the distance is calculated by the calculation unit; and a display update control unit that prohibits the update of the distance on display at the display unit and sustains the display of the previously calculated distance at the display unit according to a change in the most recently calculated distance calculated most recently by the calculation unit relative to the previously calculated distance having been calculated previously by the calculation unit.

Abstract: A lens-fitted photo film unit includes a flash emitter for emitting flash light toward a photographic object in flash photography. A flash amount control circuit quenches flash emission of the flash emitter when a value of integration of light reflected by the object as measured by a first sensor in the flash photography comes up to a predetermined level. An aperture stop device designates one of a large aperture state and a small aperture state. A switch disables the flash amount control circuit if the small aperture state is designated, and enables the flash amount control circuit if the large aperture state is designated. The switch regulates operation of the flash amount control circuit in order to raise an amount of the flash light at a time of the flash photography in the small aperture state.

Abstract: A lens-fitted photo film unit includes a flash emitter for emitting flash light toward a photographic object in flash photography. A flash amount control circuit quenches flash emission of the flash emitter when a value of integration of light reflected by the object as measured by a first sensor in the flash photography comes up to a predetermined level. An aperture stop device designates one of a large aperture state and a small aperture state. A switch disables the flash amount control circuit if the small aperture state is designated, and enables the flash amount control circuit if the large aperture state is designated. The switch regulates operation of the flash amount control circuit in order to raise an amount of the flash light at a time of the flash photography in the small aperture state.

Abstract: A data-imprinting apparatus for preventing the imprinting of incorrect dates in a lens-equipped film unit that lacks a monitor display unit for the confirmation of the date display. The lens-equipped film unit 1 contains a built-in data module 27 that lacks an external display unit that allows the confirmation of the date display from the outside. The data module 27 contains a transmission-type liquid crystal display unit 45 that automatically updates and displays dates based upon a pre-stored calendar. In the liquid crystal display unit 45, external light enters from the light collection window 15 on the front cover 12, thus creating a beam of data light. The data light, acting in concert with the shutter release operation, is guided into a dark box. The image-forming optical system that is provided in the dark box forms an image of the data light on a part of the photographic film.

Abstract: A lens-fitted photo film unit includes a photo film housing. A photo film roll chamber is formed in the photo film housing and pre-loaded with photo film in a roll form. A cassette holder chamber incorporates a photo film cassette, to wind the photo film therein after being exposed. A flash-emission main capacitor stores charge by a charging operation. A flash discharge tube emits flash light by a discharging operation of the charge. A flash circuit controls the main capacitor and the flash discharge tube for effecting the charging operation and the discharging operation. An EEPROM is incorporated in the photo film cassette. A write control IC is incorporated in the photo film housing, for writing information to EEPROM. A battery supplies the flash circuit and the write control IC with power. A charge control signal generator or BUSY terminal is disposed in the write control IC, and supplies the flash circuit with a low-level inhibit signal, to inhibit the flash circuit from effecting the charging operation.

Abstract: In a flash circuit of a flash device, a Zener diode (37) is connected to a tap point (23f) located at an intermediate position of a secondary coil of an oscillation transformer (23). The oscillation transformer (23) and an oscillation transistor (22) constitutes an oscillation circuit. A potential at the tap point (23f) changes proportionally to a voltage charged in a main capacitor (41). When the main capacitor (41) is charged up to a set voltage, the Zener diode (37) conducts a Zener current, which activates a stopping transistor (38) and thus deactivates the oscillation circuit. When a flash charge switch (51) is turned on, an end of a light guide portion of a charge condition indicator (60) protrudes out of a lens-fitted film unit. When the main capacitor (41) is charged up to the set voltage, a light emission element starts lighting and the light from the light emission element is projected from the end of the light guide portion.

Abstract: A photo diode and a resistor are connected to each other in series. A gate of a FET is connected to the connection of the photo diode and the resistor. When a photometry switch is turned on, the photo diode generates a photo current according to a subject brightness. A potential difference is generated between the both terminal of the resistor. When the subject brightness is less than a threshold level, the FET is not turned on because of low potential difference of the resistor. When a subject brightness is equal to or more than the threshold level, the FET is turned on because of high potential difference of the resistor. A first transistor turned to be in a state opposite to the FET and a second transistor turned on and off according the state of the first transistor are provided. When the FET is turned off, the second transistor is turned on, and a solenoid is powered. The solenoid moves a stop plate out of an optical axis such that an exposure is taken through a large stop opening.

Abstract: In a flash circuit of a flash device, a Zener diode (37) is connected to a tap point (23f) located at an intermediate position of a secondary coil of an oscillation transformer (23). The oscillation transformer (23) and an oscillation transistor (22) constitutes an oscillation circuit. A potential at the tap point (23f) changes proportionally to a voltage charged in a main capacitor (41). When the main capacitor (41) is charged up to a set voltage, the Zener diode (37) conducts a Zener current, which activates a stopping transistor (38) and thus deactivates the oscillation circuit. When a flash charge switch (51) is turned on, an end of a light guide portion of a charge condition indicator (60) protrudes out of a lens-fitted film unit. When the main capacitor (41) is charged up to the set voltage, a light emission element starts lighting, and the light from the light emission element is projected from the end of the light guide portion.

Abstract: A lens-fitted film unit with an exposure mechanism which is equipped with a built-in flash and a pre-loaded film cartridge is provided with an IC memory in which exposure data is written, a write control IC operative to control writing data on an exposure in the IC memory, and a switch arrangement comprising a synchronizing switch which is actuated by a shutter blade of the exposure mechanism to cause the built-in flash to make a flash and an auxiliary switch which is actuated by operation of the shutter mechanism. The write control IC is actuated to control writing data on an exposure in the IC memory when at least one of the synchronizing and auxiliary switches is actuated during making the exposure. The built-in flash has a charge switch opetative to be turned on for charging a capacitor of the built-in flash and to remain turned on until turned off.

Abstract: In a flash circuit of a flash device, a Zener diode (37) is connected to a tap point (23f) located at an intermediate position of a secondary coil of an oscillation transformer (23). The oscillation transformer (23) and an oscillation transistor (22) constitutes an oscillation circuit. A potential at the tap point (23f) changes proportionally to a voltage charged in a main capacitor (41). When the main capacitor (41) is charged up to a set voltage, the Zener diode (37) conducts a Zener current, which activates a stopping transistor (38) and thus deactivates the oscillation circuit. When a flash charge switch (51) is turned on, an end of a light guide portion of a charge condition indicator (60) protrudes out of a lens-fitted film unit. When the main capacitor (41) is charged up to the set voltage, a light emission element starts lighting, and the light from the light emission element is projected from the end of the light guide portion.

Abstract: An electronic flash device equipped with LED indicator for providing an indication of completion of charging a main capacitor and a circuit for lowering power consumption has a controlling transistor operative to control a base current of the oscillating transistor which increases or decreases a primary current flowing through a primary winding and to be turned conductive by a current supplied from a battery through a current limiting resistor to start supply of the base current of the oscillating transistor. A secondary current generated in a secondary winding increases the base current of the controlling transistor, which increases the base current of the oscillating transistor which is lowered by the current limiting resistor having a large resistance and is increased or decreased by the controlling transistor.

Abstract: A switching circuit is connected to an oscillation transistor of a charging circuit of a flash device of a lens-fitted photo film unit, for turning on or off the oscillation transistor. When a rear cover of a unit body of the film unit is separated, a battery for supplying the flash device is disconnected from the flash device through an insulating plate that is provided on the front cover. Thereafter when the battery or a new battery is connected to the flash device, a clear circuit outputs a clear signal to the switching circuit and a restoring circuit to initialize these circuits. In the initialized position, the switching circuit turns off the oscillation transistor, and maintains this switching condition until a restore signal is applied from the restoring circuit. The restoring circuit outputs the restore signal only when a predetermined cancel signal is applied from an external device.

Abstract: A data-imprinting apparatus for preventing the imprinting of incorrect dates in a lens-equipped film unit that lacks a monitor display unit for the confirmation of the date display. The lens-equipped film unit 1 contains a built-in data module 27 that lacks an external display unit that allows the confirmation of the date display from the outside. The data module 27 contains a transmission-type liquid crystal display unit 45 that automatically updates and displays dates based upon a pre-stored calendar. In the liquid crystal display unit 45, external light enters from the light collection window 15 on the front cover 12, thus creating a beam of data light. The data light, acting in concert with the shutter release operation, is guided into a dark box. The image-forming optical system that is provided in the dark box forms an image of the data light on a part of the photographic film.

Abstract: A photo diode and a resistor are connected to each other in series. A gate of a FET is connected to the connection of the photo diode and the resistor. When a photometry switch is turned on, the photo diode generates a photo current according to a subject brightness. A potential difference is generated between the both terminal of the resistor. When the subject brightness is less than a threshold level, the FET is not turned on because of low potential difference of the resistor. When a subject brightness is equal to or more than the threshold level, the FET is turned on because of high potential difference of the resistor. A first transistor turned to be in a state opposite to the FET and a second transistor turned on and off according the state of the first transistor are provided. When the FET is turned off, the second transistor is turned on, and a solenoid is powered. The solenoid moves a stop plate out of an optical axis such that an exposure is taken through a large stop opening.

Abstract: A write control IC is incorporated in the photo film housing, for writing information to EEPROM. A battery supplies the flash circuit and the write control IC with power. A charge control signal generator or BUSY terminal is disposed in the write control IC, and supplies the flash circuit with a low-level inhibit signal, to inhibit the flash circuit from effecting the charging operation. The write control IC controls the charge control signal generator, to write the information while the flash circuit is inhibited from effecting the charging operation. A power source voltage of the battery is prevented from dropping while the information is written.

Abstract: A lens-fitted photo film unit includes a photo film housing. A photo film roll chamber is formed in the photo film housing and pre-loaded with photo film in a roll form. A cassette holder chamber incorporates a photo film cassette, to wind the photo film therein after being exposed. A flash-emission main capacitor stores charge by a charging operation. A flash discharge tube emits flash light by a discharging operation of the charge. A flash circuit controls the main capacitor and the flash discharge tube for effecting the charging operation and the discharging operation. An EEPROM is incorporated in the photo film cassette. A write control IC is incorporated in the photo film housing, for writing information to EEPROM. A battery supplies the flash circuit and the write control IC with power. A charge control signal generator or BUSY terminal is disposed in the write control IC, and supplies the flash circuit with a low-level inhibit signal, to inhibit the flash circuit from effecting the charging operation.

Abstract: A lens-fitted photo film unit includes a photo film housing. A photo film roll chamber is formed in the photo film housing and pre-loaded with photo film in a roll form. A cassette holder chamber incorporates a photo film cassette, to wind the photo film therein after being exposed. A flash-emission main capacitor stores charge by a charging operation. A flash discharge tube emits flash light by a discharging operation of the charge. A flash circuit controls the main capacitor and the flash discharge tube for effecting the charging operation and the discharging operation. An EEPROM is incorporated in the photo film cassette. A write control IC is incorporated in the photo film housing, for writing information to EEPROM. A battery supplies the flash circuit and the write control IC with power. A charge control signal generator or BUSY terminal is disposed in the write control IC, and supplies the flash circuit with a low-level inhibit signal, to inhibit the flash circuit from effecting the charging operation.

Abstract: In a flash device, a three-terminal switch is provided for connecting or disconnecting between a secondary coil of an oscillating transformer and a base of an oscillating transistor, between the secondary coil of the oscillating transformer and a triggering capacitor, and between the triggering capacitor and a primary coil of a triggering transformer. When the three-terminal switch is turned on, a biasing current is supplied to the base of the oscillating transistor, so a current flows through a primary coil of the oscillating transformer, and a secondary current from the secondary coil of the oscillating transformer is supplied to the main capacitor through the three-terminal switch and a base-emitter circuit of the oscillating transistor, to charge the main capacitor. The secondary current is also supplied to the triggering capacitor through the three-terminal switch, to charge the triggering capacitor.

Abstract: A lens-fitted photo film unit has an electronic flash device (11, 30; 115) with a printed circuit board (173). The flash device includes a flash-emitting section (6, 170) for emitting flash light toward a photographic field, and a main capacitor (31, 155) for storing charge to be discharged in the flash-emitting section. The printed circuit board converts a current of a battery (12, 127) into a current of high voltage to be supplied to the main capacitor. The printed circuit board has a transistor (13, Tr1) for oscillation. A primary winding (15) has one end connected to the battery, and another end connected to a collector of the transistor. A secondary winding (16) is combined in mutual induction with the primary winding, has one end connected to the main capacitor, and another end connected to a base of the transistor. A tertiary winding (17) is combined in mutual induction with the secondary winding, has one end connected to the battery, and another end connected to the base of the transistor.