THE EFFECTS OF RF INTERFERENCE, MULTIPATH AND SIGNAL OBSTRUCTION ON THE GPS OBSERVABLES

An optical scanning apparatus is capable of scanning a surface with a plurality of fluxes of light along a principal scanning direction. In the apparatus, a plurality of fluxes of light are emitted by a plurality of light sources arranged at intervals along an auxiliary scanning direction perpendicular to the principal scanning direction. The plurality of fluxes of light are lead to an optical deflector via an optical system for incident light and deflected by the optical deflector. Most part of the deflected fluxes of light are lead to the surface via an imaging optical system for scanning the surface, while small part of the deflected fluxes of light are lead to a photodetector to generate a synchronizing signal for controlling the timing of the scanning start of each of the fluxes of light. A slit is arranged between the optical deflector and the photodetector and the slit is inclined relative to the auxiliary scanning direction, whereby the scanning start timings for the plurality of fluxes of light are adjusted. The optical scanning apparatus is used in an image forming apparatus or an electrophotographic printer.

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