摘要 |
A system according to an embodiment of the present invention includes one or more first optical sensors and one or more second optical sensors. The first optical sensor(s) each include a photodetector region and a plurality of first slats over the photodetector region. The second optical sensor(s) each include a photodetector region and a plurality of second slats over the photodetector region, wherein the second slats have a different configuration than the first slats. For example, the second slats can be orthogonal relative to the first slats. For another example, the first slats can slant in a first direction, and the second slats can slant in a second direction generally opposite the first direction. Currents produced by the first optical sensor(s) and the second optical sensor(s), which are indicative of light incident on the optical sensors, are useful for distinguishing between movement in at least two different directions. |