Abstract: A distance measuring device for ensuring accuracy of the positional relationship between the optical axis of a light-receiving lens and the optical center of a light-receiving element obtains distance information data by measuring the distance to a target plate which is 1 meter from the distance measuring device. If the distance information is not smaller than 1.625 meter, a switch is connected to one pair of terminals and the difference between reference output data stored in a control circuit and output data of an AF-IC obtained when the distance to the target plate is measured with the switch connected to the pair of terminals is calculated and stored in a memory circuit. When the value of the distance information data is not greater than 0.375 meter, the switch is connected to another pair of terminals, and output deviation data is stored in the memory circuit 11 in the same way. When the value of the distance information value is smaller than 1.625 meter and greater than 0.

Abstract: A photographic camera has a rectilinear approximate operation circuit for calculating characteristic correction data for correcting errors in the operational characteristics of the camera. Predetermined theoretical characteristic data dependent on operational characteristics of the camera are stored. Measured data corresponding to predetermined measured values are stored as individually measured characteristic data in a nonvolatile EEPROM so that the stored measured data can be easily changed by rewriting the EEPROM. An object signal is generated depending on an object to be photographed. The rectilinear approximate operational circuit calculates characteristic correction data from the object signal, the theoretical characteristic data and the measured characteristic data, which is then used for correcting errors in the operation characteristics of the camera.

Abstract: A camera has a shutter which may also constitute a diaphragm. In a multi-flash mode the shutter selectively has a maximum aperture at an onset or at the end of the time base. The flash occurs in synchronism with a shutter waveform shaped by this aperture area and a time base element. In a second embodiment, a second diaphragm setting circuit is provided, in diaphragm priority photography, for computing a measurement value of a distance to a subject and a second diaphragm value from the guide number during an emission of flashed light. The diaphragm is set to the computed second diaphragm value, ad an electronic flash is energized with a desired aperture area. The diaphragm is set to an initial value to effect the photography at a time other than during the emission of flashed light. A timing circuit may be provided for setting the diaphragm to the second diaphragm value.

Abstract: In the distance measuring device for an automatic focusing camera, the reliability is improved by preventing the device from electric noise, and the structure is simplified so as to provide interchangeability to reduce the production cost. A light receiving lens 2 and a multilayer printed circuit board 3 are mounted on a holder 1. A potting frame 6 is provided on the lens-facing side surface of the printed circuit board 3. An optical sensor 4 and an IC 5 are both mounted within a space 3 enclosed by the potting frame 6, and sealed by a protecting resin 7 simultaneously. Further, resistors S and capacitors C of a distance measuring circuit are mounted on the opposite surface of the printed circuit board 3. Both the surfaces of the printed circuit board 3 are connected to each other via a through hole to construct the distance measuring circuit. The protecting resin 7 transmits light having specified wave lengths.