Abstract: A computer or calculator for calculating dates or a period of days, wherein a selector device is provided for selecting any one of a plurality of predetermined sequences or orders in which input date data may be manually entered.

Abstract: A sound device incorporated camera has an indication signal forming circuit for producing a warning signal, a signal indicative of the fact that the operation of the self-timer is in progress, or the like, and a sound producing device for converting the output signal from said circuit to a sound.

Abstract: The present invention relates to a photographic camera device in which current is supplied to the winding up motor device for automatically advancing the film and cocking the shutter and to a rechargeable electronic flash light device from a single common power source battery. The camera is provided with a voltage detecting device for detecting the voltage of the power source battery, and a control device for simultaneously supplying current to the winding up motor device and the flash light device when the power source voltage detected by the voltage detecting device is higher than a certain determined voltage, and for preventing current flow to the flash light device while the current is being supplied to the winding up motor device when the detected power source voltage is lower than the determined voltage.

Abstract: An exposure control device for a camera, having a first light receiving element for sensing light beams reflected from a film surface and a second light receiving element for sensing light beams from an object before taking a photograph. In this arrangement an auxiliary diaphragm, which is opened as a shutter is closed and is closed as the shutter is opened, is provided in front of the second light receiving element. The first and second light receiving elements are connected in parallel between input terminals of an operational amplifier for the light measuring. Accordingly, an exposure control with a high degree of accuracy is effected based on an output of the light measuring operational amplifier.

Abstract: A filter for compensation of spectral sensitivity is provided in front of a light receiving element through a light shielding tube. A light source emitting such light as having wave length characteristics which fall within a sensitive wave length zone of the light receiving element yet fall outside of transmitting wave length zone of the filter is provided between the filter and the light receiving element. Light from outside irradiates the light receiving element through the filter while light from the light source is so controlled as irradiating the light receiving element but not leaking through the filter to outside, so that the light from the light source can irradiate the light receiving element without any relationship with the irradiation of outside light on the light receiving element.

Abstract: A computer capable of rounding a number, such as by raising, truncating or chopping the digits of the number which are lower than a specified digit position above a decimal point.