| 摘要 |
An optical fingerprint sensor (100) comprising; a lens (2); a filter (30); a reflector (31); an image capture module (41); a light source (1). The lens has two separate areas for detection (Fig. 2). There is a light source which illuminates the lens, and reflects light from the fingertip, forming two partial images of the fingerprint (Fig. 4). A filter is directly below a first area of the lens (21), and reflects the first partial image (101) of the fingerprint to the image capture module. A reflector is directly below a second area (22) of the lens, and reflects the second partial image (102) of the fingerprint through the filter, to the image capture device. The image captured contains two partial fingerprint images, which both have some features in common (23, Fig. 4), due to the overlap of the detection areas. The advantage of this invention is that it reduces the thickness of the sensor needed to capture an entire fingerprint. The filter may be a polarization beam splitter, dichroic filter or light filter. |
