초록 ▼

Method and apparatus are disclosed which direct a preliminary pulse of radiation from a selectively energizable light source toward a subject, and a device for evaluating the amplitude of the reflected pulse of radiation therefrom so as to determine a weighted range signal as a function of the ampli

Method and apparatus are disclosed which direct a preliminary pulse of radiation from a selectively energizable light source toward a subject, and a device for evaluating the amplitude of the reflected pulse of radiation therefrom so as to determine a weighted range signal as a function of the amplitude of generally non-visible radiation frequencies selected for reducing the non-uniformity in reflectivity values of reflected visible radiation in the scene, which weighted range signal includes a reflectivity factor and a range factor. The reflectivity factor, which detracts from the range factor for focusing, significantly enhances exposure control under certain scene lighting conditions.

대표청구항 ▼

A camera comprising: a lens assembly for directing image-carrying light rays along a given path from a photographic scene to a focal plane; a shutter system for controlling the transmission of light from the scene to the focal plane so as to define an exposure interval during an evaluation period; m

A camera comprising: a lens assembly for directing image-carrying light rays along a given path from a photographic scene to a focal plane; a shutter system for controlling the transmission of light from the scene to the focal plane so as to define an exposure interval during an evaluation period; means for first actuating a light source, configured to produce radiation which essentially comprises simultaneously of both visible and non-visible electromagnetic frequencies, to direct a first pulse of said radiation of given intensity toward a subject in the scene prior to commencement of or in the early stages of said exposure interval to evaluate the subject including its distance from the camera, and for subsequently actuating the same source to direct a second pulse of said radiation toward the scene during said exposure interval to artificially illuminate the subject for photographic recording during exposure; means for evaluating the intensity of primarily non-visible light from the scene during the first pulse of illumination; and means responsive to the evaluated intensity of the scene resulting from reflection of the first pulse for controlling at least one photographic function, whereby non-visible frequencies from the source are utilized for subject evaluation and subsequent photographic control, and the visible frequencies from the same source are utilized for scene illumination for photographic recording during the exposure interval.