| 摘要 |
One embodiment relates to a laser positioning device for sensing relative movement between a data input device and a surface by determining displacement of image features in a succession of images of the surface. The device forms a single integrated package, which includes a planar substrate and a transparent encapsulant that also embodies a collimating lens. Both a coherent light source and a sensor array and associated circuitry are configured on the planar substrate. Another embodiment relates to a method of sensing relative movement between a data input device and a surface. Coherent light is emitted from a laser and collimated so as to form a collimated illumination beam with a predetermined diameter, D, and a substantially uniform phase front. A speckle pattern is generated by impingement of the collimated illumination beam on the surface and detected by a sensor array. Other embodiments are also disclosed. |
