Abstract: Display systems, control systems for a display and a method for operating a display are provided in which people are detected a presentation space within which content presented by the display can be observed. Viewing areas are defined for each person with each viewing area comprising a less than all of the presentation space and including an area corresponding to each person. One channel of image content is obtained for presentation to each person and a combination image is presented on the display. The combination image is modulated so that each area of the combination image presented by the display is viewable only in selected areas of the presentation space. The combination image has image content from each channel of image content arranged in areas of said combination image so that, when modulated, the image content from each channel of image content is viewable only in a viewing area defined for the person for whom the content is obtained.

Abstract: Methods and control systems are provided for operating a display capable of presenting content within a presentation space. In accordance with the method, a person is located in the presentation space and a viewing space is defined comprising less than all of the presentation space and including the location of the person. Content is presented so that the presented content is discernable only within the viewing space.

Abstract: A focus detecting system is provided for detecting the focus condition of a moving image in an optical system. The focus detecting system includes means for detecting the sharpness of a plurality of sub-images formed along a plurality of sight lines by the optical system, the detecting means including a plurality of detectors arranged in a plane tilted with respect to an optical axis of said optical system and the detectors aligned with a direction of motion of the image formed by the optical system such that the sub-images are detected at a plurality of positions in the vicinity of best focus of the optical system. A time delay is provided between the sub-images such that the sub images represent the same portion of a scene being imaged by the optical system. A position of best focus for said optical system is calculated from the sub-image data.