Abstract: A system for scanning or tracking, which includes a polygon rotatable about a rotational axis. The system further includes a fixed radiation source directing radiation at the polygon along a path whose extension would intersect the rotational axis of the polygon. The intersection of the extended path with the rotational axis of the polygon constitutes an original imaginary intersection point. The system includes a first scanned region onto which the radiation is projected, the projection being characterized in that radiation emanating from the radiation source is reflected from the polygon and is made to propagate, prior to impinging on the first scanned region, along a path which includes at least one additional path segment with the additional path segment passing through or directed at an additional intersection point, the additional intersection point being a real or imaginary image of the original intersection point.

Abstract: An optical scanner including a light source which is turned ON and OFF in accordance with drawing data. A hologram deflector, made of a rotatable planar hologram disc, provided with a plurality of hologram facets through which light emitted from the light source passes, is rotated to scan an image surface with light emitted from the light source. An optical detector detects light passing in a scanning direction through at least a first reference point, for the commencement of the scanning, and a second reference point, for the completion of the scanning. A scanning time detector detects a scanning time period in which the light deflected by each hologram facet of the hologram disc, passes the first reference point and reaches the second reference point. Finally, a frequency varying device varies the frequency of the light source for each hologram facet in accordance with a unique scanning time period directed by the scanning time detector for each hologram facet.

Abstract: A method and apparatus are provided for emitting a laser like monochromatic narrow beam of light at a selected wavelength from a heated emitter member having a plurality of parallel layers while reducing emission at other wavelengths of light. The parallel layers are overlaid with each other. Each of the parallel layers extends transversely for a particular width. A heat source stimulates the emitter member to emit photons, which are determined by the composition of materials within the emitter member. The emitter member emits monochromatic light at a selected wavelength in response to the photon emissions. The selected wavelength of the monochromatic light is determined by the width of the layers of the emitter member. Light at other wavelengths does not transmit through and their emissivity also decreases.