Abstract: An auto-focus arithmetic device suitable for use in a photographic camera is provided. The device includes a photographic lens which is movable along a predetermined optical axis and a CCD for detecting light coming from a subject of interest through the lens. An arithmetic unit for determining the direction and amount of movement of the lens with respect to the subject of interest based on a detection signal from the CCD is provided. The arithmetic unit includes an integer portion calculating sub-unit for calculating an integer portion of the detection signal and a fractional portion calculating sub-unit for calculating a fractional portion of the detection signal. The fractional portion calculating sub-unit remains deactivated as long as the detected amount of discrepancy from the in-focus condition is larger than a predetermined level; however, it is activated when the detected amount of discrepancy becomes equal to or less than the predetermined level.

Abstract: An automatic focusing device for use in a camera using photographic lenses having a variable power region in which an entire focal length of a variable power optical system comprising a variable power lens group, a focusing lens group and a macro lens group disposed on an identical optical axis can optionally be set by the variable power lens group between a shortest focal length and a longest focal length, a macro region capable of macro photographing by the macro lens group, a variable power focusing region from an infinite position to a nearest position on the optical axis corresponding to an object distance from an infinite distance to a nearest distance and a macro focusing region capable of macro photographing in a predetermined region disposed from a nearest position on a side opposite to an infinite position.

Abstract: An apparatus for controlling a motor in a camera including, a motor drive unit for driving the motor in a prescribed sequence, a braking device for applying the brakes on the motor in accordance with the prescribed sequence, and a speed detecting unit for monitoring the speed of the motor and permitting initiation of the next action only after the speed of the motor, in consequence of application of the brakes by the braking device, is brought to a level incapable of obstructing the next action.

Abstract: An automatic focusing control system includes a focus detecting light detector, a rangefinder, a lens driver, a manual range setting unit, a mode setting unit, and a control unit. When a manual mode is selected by the mode setting unit, the control unit applies a lens driving signal from the manual range setting unit to the lens driver unit to drive a lens. When an automatic mode is selected by the mode setting unit, the control unit operates the lens driver unit to drive the lens based on a measured distance at the time distance measurement is possible, applies the lens driving signal from the manual range setting unit to the lens driver unit at the time distance measurement is impossible, and operates the lens driver unit to drive the lens based on the measured distance at the time distance measurement becomes possible from a condition in which distance measurement is impossible.

Abstract: An image signal amplifier circuit includes an amplifier for amplifying an image signal from a focusdetecting self-scanned image sensor, and a monitor photodetector for detecting the brightness of an object to be photographed. The amplification degree of the image signal is controlled by an automatic gain controller in the amplifier based on an output signal from the monitor photodetector so that the image signal as amplified will be of a constant level. An offset voltage is added to an output signal from the amplifier.

Abstract: A charge-coupled device has a plurality of photodiode arrays, a plurality of storage electrodes, a pluratity of shift gates, a plurality of reset terminals, and a plurality of shift terminals, which can be operated at different timings. Object images detected by the charge-coupled device at a certain time interval are compared for camera shake detection.

Abstract: A quick mirror return mechanism includes a return spring and a quick return setting member, which are formed, in the region where they abut against each other, so that as the return spring is stressed, the resilient force of the return spring is directed closer to the direction in which a setting pawl moves. A main mirror for a finder, a stationary member, a mirror-up lever, a main mirror drive, a sub-mirror and a sub-mirror driver form together a six-bar linkage wherein the main mirror moves upward while swinging back and the sub-mirror moves into overlapping relationship with the main mirror when the latter has completed its upward movement. The quick return mechanism which is biased with an increased force is disposed on a front panel of a camera, thus preventing any excessive force from being applied to a mirror box. A light receiving element unit is disposed in the bottom of the mirror box.

Abstract: An auto-focusing method includes a scanning step for scanning a pair of solid-state image sensors on which light from a subject of interest impinges as passing through a focusing lens, an A/D conversion step, a Fourier transformation step, a convolution operation step, a peak detection step for determining an amount of displacement of said lens from the results of said convolution, and a lens displacement step for displacing said lens according to the displacement amount thus determined. The present auto-focusing method is least susceptible to noises and not adversely affected by differences in contrast of the subject of interest.

Abstract: A quick mirror return mechanism includes a return spring and a quick return setting member, which are formed, in the region where they abut against each other, so that as the return spring is stressed, the resilient force of the return spring is directed closer to the direction in which a setting pawl moves. A main mirror for a finder, a stationary member, a mirror-up lever, a main mirror drive, a sub-mirror and a sub-mirror driver form together a six-bar linkage wherein the main mirror moves upward while swinging back and the sub-mirror moves into overlapping relationship with the main mirror when the latter has completed its upward movement. The quick return mechanism which is biased with an increased force is disposed on a front panel of a camera, thus preventing any excessive force from being applied to a mirror box. A light receiving element unit is disposed in the bottom of the mirror box.