Abstract: This invention relates to an automatic camera exposure control device comprising a first light measuring circuit including a photoelectric element receiving light through the objective lens of the camera and generating a first output proportional to the logarithm of the brightness of an object to be photographed, and a circuit for providing a second output indicative of the film sensitivity and the lens aperture value, the light measuring circuit for providing a first signal indicative of the sum of the first and second outputs and a second circuit including a pulse genrator circuit for generating clock pulses and a counter for counting the clock pulses and for producing a second signal of a stairstep waveform corresponding to the counting of a pulse; a voltage comparator circuit for comparing the second signal with the first signal and for producing a signal when the level of the second signal exceeds that of the first signal; a third circuit composed mainly of a gate circuit for stopping the counting of the

Abstract: An automatically light adjusted luminous indicator observable through a camera view finder includes a photoconductor exposed to the camera incident light and either constitutes or controls the resistance component of a frequency controlling RC network of a relaxation oscillator. The output of the relaxation oscillator controls a bi-stable multivibrator whose output is coupled through a switching transistor to the primary of a transformer whose secondary is connected to a light emitting member such as an electroluminescent device or a light emitting diode. The parameters of the network are adjusted so that the luminosity of the indicator and viewed image are about equal or within any desired ratio range. The photoconductor may also control an exposure control network.

Abstract: An automatic exposure time control circuit for use with a camera having a shutter. A light measuring circuit for measuring the scene brightness passing through the camera lens produces an electric signal proportional to the logarithm of the scene brightness. An A-D converter circuit converts the output signal from the light measuring circuit to a digital signal. A first decoder, having a plurality of output terminals, receives the converted, digital signal and produces an output at a corresponding one of the output terminals. An exposure time control circuit, comprising a binary counter having the same number of stages and output terminals as the number of output terminals of the first decoder is set to the output of the decoder upon release of the shutter.

Abstract: In an exposure meter having a row of lighting elements, such as lamps or light-emitting diodes, which correspond to respective exposure values, an improvement is made in that by utilizing a capacitor-charging integrating circuit, a constant current circuit and a ring-counter, an exposure value between two neighboring steps of the above-mentioned exposure values can be indicated by lighting said two lighting elements, and in that ranges of exposure indication can be switched by shifting a dial plate, which is facing the lighting elements, in interlocking relation with a range-shifting switch for switching its circuit for range selection, thus enabling a doubling of the steps of exposure values to be indicated with a limited number of lighting elements.

Abstract: This invention relates to an automatic camera exposure control device comprising a first light measuring circuit including a photoelectric element receiving light through the objective lens of the camera and generating a first output proportional to the logarithm of the brightness of an object to be photographed, and a circuit for providing a second output indicative of the film sensitivity and the lens aperture value, the light measuring circuit for providing a first signal indicative of the sum of the first and second outputs; and a second circuit including a pulse generator circuit for generating clock pulses and a counter for counting the clock pulses and for producing a second signal of a stairstep waveform corresponding to the counting of a pulse; a voltage comparator circuit for comparing the second signal with the first signal and for producing a signal when the level of the second signal exceeds that of the first signal; a third circuit composed mainly of a gate circuit for stopping the counting of t