| 摘要 |
A deflected beam optical scanning system is disclosed including means for generating a composite beam (24) having at least one scanning beam (14) which impinges at spot (42) on scanned surface (38) and a position sensing beam (18) which impinges at spot (58) on encoding surface (56) of encoding and collecting rod (52). A rotating mirror (28) causes spots (42 and 58) to move synchronously respectively across scanned surface (38) and encoding surface (56). As spot (58) moves along encoding surface (56), a patterned structure (64) on its surface imposes modulation on position sensing beam (18). Modulation of position sensing beam (18) indicates movement of scanning beam (14) across scanned surface (38). Encoding and collecting rod (52) gathers the modulated light and supplies it to encoder light-detection diode (72). An electronic circuit uses the modulation of beam (18), sensed by the encoder light-detection diode (72), to continuously measure the location of scanning beam (14) on scanned surface (38). |
