Live print scanner with holographic platen
View Patent ↗This invention relates to the use of holographic optical elements in the design and application of biometric scanning instruments used typically for capturing biometric information such as fingerprints and handprints. A live print scanning system for generating a high contrast print image is presented. The system includes a flatbed scanner with a scanning surface and an image sensor, a holographic platen placed on the scanning surface, and a reference beam source that provides a reference beam to the holographic platen. A high contrast print image of a biometric object that is placed on the holographic platen is obtained at the image sensor. A method for generating a high contrast print image is also presented.
1. A system for capturing light from a holographic platen, the holographic platen being formed from a holographic element, onto an image sensor in order to generate a print image of a biometric object, comprising:
a flatbed scanner including a scanning surface that supports the holographic platen and an image sensor; and
a reference beam source that provides a reference beam to the holographic platen,
wherein the holographic platen receives the biometric object on a top surface thereof, and
wherein the reference beam interacts with the biometric object through reflection from the top surface of the holographic platen, such that, when the biometric object is present on the holographic platen, biometric information correlating to the biometric object is formed through frustrated total internal reflection and the holographic platen directs the biometric information onto the image sensor.
2. The system of claim 1 , wherein the reference beam source comprises an illumination system within the flatbed scanner.
3. A method for capturing light from a holographic platen, the holographic platen being formed from a holographic element, onto an image sensor in order to generate a print image of a biometric object, comprising:
receiving the biometric object on a top surface of the holographic platen, the holographic platen being supported by a scanning surface of a flatbed scanner;
directing a reference beam onto the holographic platen, the reference beam reflecting through the holographic platen to interact with the biometric object, such that, when the biometric object is present on the holographic platen and through frustrated total internal reflection between the reference beam reflecting from the holographic platen, biometric information corresponding to the biometric object is directed onto an image sensor that is coupled to the scanning surface of the flatbed scanner.