Wheel driver and portable electronic device having the same

摘要

A pattern wheel driver is provided. The pattern wheel driver includes a rotatable pattern wheel with patterned regions repeatedly formed on the pattern wheel. Each of the patterned regions has a plurality of patterns. Each of the plurality of patterns has a different width. The pattern wheel driver also includes a detector for detecting the plurality of patterns, mounted at a position where the patterned regions of the pattern wheel pass when the pattern wheel rotates. The pattern wheel driver also includes an encoder for producing a signal indicating whether the pattern wheel rotates in a forward direction or a reverse direction based on signals produced by the detector.

主权项

1. A pattern wheel driver comprising:
a rotatable pattern wheel with patterned regions repeatedly formed on the pattern wheel, each of the patterned regions having a plurality of patterns, wherein each pattern of the plurality of patterns has a different width; only a single photodiode configured to detect the plurality of patterns, the single photodiode mounted at a position where the patterned regions of the pattern wheel pass when the pattern wheel rotates; and an encoder configured to produce a signal indicating whether the pattern wheel rotates in a forward direction or a reverse direction based on signals produced by the only a single photodiode, wherein each of the patterned regions has at least one of at least three reflective sections with differing widths or at least three non-reflective sections with differing widths.