Small reliable image input apparatus incorporated in finger-print collation system of personal identification
First Claim
1. An image input device for producing a piece of data information representative of a fingerprint of a finger of a living body, comprising:
- a transparent optical guide plate including a first surface having an detecting area where said living body presses said finger, and radiating a reflection representative of an image of said fingerprint from a second surface to the outside thereof;
a light source attached to an incident area of a third surface of said transparent optical guide plate narrower than said detecting area, and diffusing light into said transparent optical guide in such a manner as to illuminate said detecting area;
an image pickup device provided in the vicinity of said second surface, and having an incident surface so as to detect said reflection;
an image forming means provided between said second surface and said image pickup device so as to form said image on said incident surface; and
a case for accommodating said transparent optical plate, said light source, said image pickup device and said image forming mean.
4 Assignments
0 Petitions
Accused Products
Abstract
An image input device has a optical guide plate exposed to a window of a photo-shield case, a pair of light emitting diodes attached to side surfaces of the optical guide plate for radiating light into it, an area image sensor provided under the optical guide plate, a gradient index lens unit provided between the optical guide plate and the area image sensor and a filter connected to the area image sensor for eliminating a low frequency component from an image carrying signal; when a person presses a finger on the optical guide plate, the fingerprint scatters the light toward the gradient index lens unit, and the area image sensor produces the image carrying signal from the incident light; the reflection on valley lines is gradually varied along the width of the finger, and the elimination of the low frequency component makes the contrast of the image clear.
-
Citations
27 Claims
-
1. An image input device for producing a piece of data information representative of a fingerprint of a finger of a living body, comprising:
-
a transparent optical guide plate including a first surface having an detecting area where said living body presses said finger, and radiating a reflection representative of an image of said fingerprint from a second surface to the outside thereof; a light source attached to an incident area of a third surface of said transparent optical guide plate narrower than said detecting area, and diffusing light into said transparent optical guide in such a manner as to illuminate said detecting area; an image pickup device provided in the vicinity of said second surface, and having an incident surface so as to detect said reflection; an image forming means provided between said second surface and said image pickup device so as to form said image on said incident surface; and a case for accommodating said transparent optical plate, said light source, said image pickup device and said image forming mean. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
-
-
13. An image input device for producing a piece of data information representative of a fingerprint of a finger of a living body, comprising:
-
a transparent optical guide plate including a first surface having an detecting area where said living body presses said finger, and radiating a reflection representative of an image of said fingerprint from a second surface to the outside thereof; a light source radiating light into said transparent optical guide so as to illuminate said detecting area; an image pickup device provided in the vicinity of said second surface, and having an incident surface so as to detect said reflection; a gradient index lens array provided between said second surface and said image pickup device so as to form said image on said incident surface; and a case for accommodating said transparent optical plate, said light source, said image pickup device and said image forming mean. - View Dependent Claims (14, 15, 16)
-
-
17. An image input device for producing a piece of data information representative of a fingerprint of a finger of a living body, comprising:
-
a transparent optical guide plate including a first surface having an detecting area where said living body presses said finger, and radiating a reflection representative of an image of said fingerprint from a second surface to the outside thereof; a light source radiating light into said transparent optical guide so as to illuminate said detecting area; an image pickup device provided in the vicinity of said second surface, and having an incident surface so as to detect said reflection; an image forming means provided between said second surface and said image pickup device so as to form said image on said incident surface; a case for accommodating said transparent optical plate, said light source, said image pickup device and said image forming mean; and an eliminating means for eliminating a sub-piece of data information representative of a sub-image of valley lines of said fingerprint from said piece of data information representative of said fingerprint. - View Dependent Claims (18, 19, 20, 21, 22)
-
-
23. An image input device for producing a piece of data information representative of a fingerprint of a finger, comprising:
-
a transparent optical guide plate including a first surface having an detecting area where said finger is pressed, and radiating a reflection representative of an image of said fingerprint from a second surface to the outside thereof; a light source radiating light into said transparent optical guide so as to illuminate said detecting area; an image pickup device provided in the vicinity of said second surface, and having an incident surface so as to detect said reflection; a gradient index lens array provided between said second surface and said image pickup device so as to form said image on said incident surface; a case for accommodating said transparent optical plate, said light source, said image pickup device and said image forming mean; and a biological information discriminating means checking said reflection to see whether or not said finger changes the reflective index with time so as to produce another piece of data information representative of a living body or non-living body. - View Dependent Claims (24, 25, 26, 27)
-
Specification