The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 25, 2012
Filed:
Apr. 17, 2008
Ming Hsieh, South Pasadena, CA (US);
Ankuo Wang, Santa Ana, CA (US);
Fei Zhou, Shenzhen, CN;
Wheshi Chen, Shenzhen, CN;
Ming Hsieh, South Pasadena, CA (US);
Ankuo Wang, Santa Ana, CA (US);
Fei Zhou, Shenzhen, CN;
Wheshi Chen, Shenzhen, CN;
3M Cogent, Inc., Pasadena, CA (US);
Abstract
An apparatus for capturing the image of a wet/moist fingerprint. The apparatus includes: a prism having an imaging plane on which a finger having valleys and ridges is place, a bottom plane parallel to the imaging plane and a reflective plane intercepting the imaging plane and intercepting the bottom plane at an angle α; a light source for generating a light with an incident angle of approximately 0° with respect to a surface normal of the imaging plane; and a lens for capturing light reflected from the reflective plane. The apparatus further includes an image sensor for generating an image of the valleys and ridges of the finger, wherein the reflective plane is arranged in such a way to meet the equation of α>45 +(arc sin (n/n))/2, where nis a refraction index of medium filled between the valleys of the finger and the imaging plane, and nis refraction index of the prism.