Patent attributes
A biometric sensor apparatus uses an infra red light source and a CMOS image sensor. A platen receives a body part and the image sensor receives light transmitted through the body part. A processor determines from the detected through-transmitted light whether the body part is live or is a spoof body part. This determination is based upon a detected variation of the opacity of the body part due to blood flow through the body part. Digital processing of the collected image signal data is performed, such as by smoothing. The sensor may further function as a pattern (such as a fingerprint) sensor for detecting surface patterns on the presented body part and identifying an individual from those sensed patterns.