초록 ▼

This invention relates to a device for focus detection or distance detection in which one or more images of a target formed by an optical system are received by photoelectric light receiving means to obtain a photoelectric output regarding the imaging condition of the image of the target and this ph

This invention relates to a device for focus detection or distance detection in which one or more images of a target formed by an optical system are received by photoelectric light receiving means to obtain a photoelectric output regarding the imaging condition of the image of the target and this photoelectric output is electrically processed through a processing circuit to thereby provide an electrical output representing the focus adjusted condition of the optical system with respect to the target or the distance to the target. According to the improvements of the present invention, such device is provided with projector means for illuminating a limited part of the detection view field determined by the focal length of the optical system and the dimensions of the effective light receiving surface of the photoelectric light receiving means, detection means for detecting whether or not the signal put out by the photoelectric light receiving means regarding the imaging condition of one or more images of the target is a sufficiently proper signal to ensure accurate focus detection or distance detection by the processing circuit, and control means for controlling the projector means in accordance with the detection output from the detection means. When proper detection is not ensured during the focus detection or the distance detection, the projector means is driven by the control means in accordance with the detection output of the detection means and the projection image of the projected light formed thereby on the target is utilized to effect focus detection or distance detection.

대표청구항 ▼

A system comprising: (A) means for forming one or more images of an object; (B) means for receiving said one or more images to provide one or more electrical outputs indicative of said one or more images, said image receiving means being signal integration type image sensing means for providing, as

A system comprising: (A) means for forming one or more images of an object; (B) means for receiving said one or more images to provide one or more electrical outputs indicative of said one or more images, said image receiving means being signal integration type image sensing means for providing, as the outputs thereof, one or more integrated image signal integrated within an integration time period; (C) means for receiving and processing said one or more electrical outputs of said image receiving means to detect the imaging condition of said one or more images formed by said image forming means; (D) means for locally illuminating said object to form an optical mark on said object; (E) means for detecting whether or not said one or more electrical outputs of said image receiving means are sufficiently proper outputs to ensure accurate imaging condition detection by said processing means, said detection means producing a detection signal when said one or more electrical outputs of the image receiving means are outputs which cannot ensure accurate imaging condition detection by the processing means; (F) said system further comprising means for controlling the integration time period of said image sensing means, said control means producing a control signal indicative of the integration time period of the sensing means; (G) means responsive to said detection signal produced by said detection means to actuate said illuminating means, said actuating means being responsive to said control signal produced by said control means to actuate said illuminating means for a time period corresponding to the integration time period of said image sensing means in accordance with said control signal and said detection signal produced by said detection means.