Abstract: Position detector for determining the rotation angle position of a rotatably supported object, comprising a light source for producing a light beam, a diffraction grating, a mirror which is connected with the object in a co-rotating manner in such a way that the light beam is reflected therefrom onto the diffraction grating and passes over the diffraction grating during a rotation of the mirror, thereby producing diffraction light, an interference device which is configured such as to be able to bring different diffraction orders of the diffraction light to interference, thereby producing an interference pattern, a light detector by means of which a brightness course, caused by the passing over of the diffraction grating with the reflected light beam, of the interference pattern can be detected, and an evaluation unit by which the rotation angle position of the object can be determined based on the brightness course.

Abstract: A divergence-changing device, comprising a ray source, a substantially telecentric arrangement, having an optical system, which has a first focal point and a first system region and a second system region, and having a ray-deflecting device, which is designed such that the beam of rays from the ray source hits the ray-deflecting device, wherein the main ray would hit/hits the ray-deflecting device at the first focal point or close to the first focal point, and that the ray-deflecting device can feed the beam of rays from the ray source to the first system region at different angles of incidence, wherein the beam of rays imaged by the first system region is deflected onto the second system region by a ray-folding device, wherein the beam of rays is imaged by the second system region such that the beam of rays hits the ray-deflecting device again and leaves the divergence-changing device with a constant position.

Abstract: Position detector for determining the rotation angle position of a rotatably supported object, comprising a light source for producing a light beam, a diffraction grating, a mirror which is connected with the object in a co-rotating manner in such a way that the light beam is reflected therefrom onto the diffraction grating and passes over the diffraction grating during a rotation of the mirror, thereby producing diffraction light, an interference device which is configured such as to be able to bring different diffraction orders of the diffraction light to interference, thereby producing an interference pattern, a light detector by means of which a brightness course, caused by the passing over of the diffraction grating with the reflected light beam, of the interference pattern can be detected, and an evaluation unit by which the rotation angle position of the object can be determined based on the brightness course.

Abstract: A position detector for a scanning device includes a movable light blocker, at least two light detectors which are located behind the light blocker and which can be covered by the light blocker at different extents of coverage as the light blocker is being moved, so that the position of the light blocker can be determined, and at least one light source for emitting light onto the light detectors. A reflector is provided which is located in front of the light blocker. The light source is arranged such that the light emitted therefrom is emitted onto the reflector. Furthermore, the reflector is arranged such that the light impinging thereon is reflected onto the light detectors.