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US5177802A Expired / Lapsed US ⏱️ 0.0 years remaining

Fingerprint input apparatus

Assignee: Sharp Corp
•
Filing: 1991-03-04
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Granted: 1993-01-05
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Expires: 2011-03-04
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Abstract

Abstract A fingerprint input apparatus is constructed to have simple construction. It serves to provide an excellen S/N ratio and reliably input a fingerprint pattern. The fingerprint input apparatus includes a light source for emitting a ray of light, a lightguide plate having a predetermined location at which a finger can be contact with the lightguide plate, a unit for directing the ray of light into at least one surfaces of the lightguide plate in a manner to keep such an angle of incidence as allowing the ray of light to be totally reflected within the lightguide plate, the lightguide plate being constructed to direct the ray of light into the predetermined location, and an image pickup unit located near the predetermined location of the lightside plate and outside of an opposite surface to a surface having the predetermined location, the image pickup unit being constructed to pick up a right irregularly reflected on a fingerprint surface of the finger contacted with the predetermined location.

Inventors

  • 👤 Yoshiji Fujimoto
  • 👤 Masayuki Katagiri
  • 👤 Naoyuki Fukuda
  • 👤 Kenji Sakamoto

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 12:22
CPC Classifications
G; G06; G06V; G06V40/00; G06V40/10; G06V40/12; G06V40/13; G06V40/1312; A; A61; A61B; A61B5/00; A61B5/117; A61B5/1171; A61B5/1172; G06V40/1335; G07; G07C; G07C9/00; G07C9/30; G07C9/32; G07C9/37

Claims Analysis

Total Claims: 25
Claim 1
Independent Claim 118 words
A fingerprint input apparatus comprising: a lightguide plate having a through hole on which a finger is placed; light sources for emitting rays of light; means for directing said rays of light into surfaces of said lightguide plate in a manner to keep such an angle of incidence as allowing said rays of light to be totally reflected within said lightguide plate, said lightguide plate being constructed to guide said rays of light to said through hole and to said finger; and an image pickup means located in opposition to said finger through said through hole therebetween, and said image pickup means being constructed to pick up light rays reflected from said finger placed on the through hole.
Claim 2
Dependent Claim 118 words
A fingerprint input apparatus comprising: a lightguide plate having a through hole on which a finger is placed; light sources for emitting rays of light; means for directing said rays of light into surfaces of said lightguide plate in a manner to keep such an angle of incidence as allowing said rays of light to be totally reflected within said lightguide plate, said lightguide plate being constructed to guide said rays of light to said through hole and to said finger; and an image pickup means located in opposition to said finger through said through hole therebetween, and said image pickup means being constructed to pick up light rays reflected from said finger placed on the through hole.
Claim 3
Dependent Claim 39 words
A fingerprint input apparatus according to claim 1, wherein said lightguide plate is made of a tabular glass plate and is formed to have a light propagating length of about 100 mm and a width of about 50 mm.
Claim 4
Dependent Claim 25 words
A fingerprint input apparatus according to claim 1, wherein said through hole has a slightly smaller diameter than an average finger diameter and is oval.
Claim 5
Dependent Claim 31 words
A fingerprint input apparatus according to claim 1, wherein two light sources included in said light sources are located as opposed to right and left end surfaces of said lightguide plate.
Claim 6
Dependent Claim 38 words
A fingerprint input apparatus according to claim 1, wherein said angle of incidence of the rays of light against said lightguide plate is adjusted to be slightly larger than a critical angle relevant to a total internal reflection.
Claim 7
Dependent Claim 20 words
A fingerprint input apparatus according to claim 1, wherein said light sources are constructed to emit parallel rays of light.
Claim 8
Dependent Claim 33 words
A fingerprint input apparatus according to claim 1, wherein said image pickup means is constructed to pick up said irregularly reflected light and to convert said irregularly reflected light into an electric signal.
Claim 9
Dependent Claim 46 words
A fingerprint input apparatus according to claim 1, wherein said lightguide plate includes two sides and an opposite surface to a light-incident surface of said lightguide plate, said two sides and said opposite surface being made of mirrors on which metal such as aluminum is vaporized.
Claim 10
Dependent Claim 20 words
A fingerprint input apparatus according to claim 1, wherein said through hole has a tapered inner wall progressively spread downwardly.
Claim 11
Dependent Claim 17 words
A fingerprint input apparatus according to claim 1, wherein said through hole has a straight inner wall.
Claim 12
Dependent Claim 23 words
A fingerprint input apparatus according to claim 1, wherein said through hole has a tapered inner wall progressively curved in a downward manner.
Claim 13
Dependent Claim 171 words
A fingerprint input apparatus comprising: a light source for emitting a ray of light; a lightguide plate having a plurality of surfaces and a predetermined contact location on one of the surfaces whereat a finger can be in contact with said lightguide plate; means for directing the ray of light into at least one surface of said lightguide plate in a manner to keep such an angle of incidence as allowing the ray of light to be totally reflected within said lightguide plate, said lightguide plate being constructed to totally reflect the light ray at least twice in the plate and to guide the ray of light within said lightguide plate into said predetermined contact location; and an image pickup means located near said predetermined contact location of said lightguide plate and outside a surface which is opposite to the surface having the predetermined contact location, said image pickup means being constructed to pick up light irregularly reflected from a fingerprint surface of the finger contacted with said predetermined contact location.
Claim 14
Dependent Claim 171 words
A fingerprint input apparatus comprising: a light source for emitting a ray of light; a lightguide plate having a plurality of surfaces and a predetermined contact location on one of the surfaces whereat a finger can be in contact with said lightguide plate; means for directing the ray of light into at least one surface of said lightguide plate in a manner to keep such an angle of incidence as allowing the ray of light to be totally reflected within said lightguide plate, said lightguide plate being constructed to totally reflect the light ray at least twice in the plate and to guide the ray of light within said lightguide plate into said predetermined contact location; and an image pickup means located near said predetermined contact location of said lightguide plate and outside a surface which is opposite to the surface having the predetermined contact location, said image pickup means being constructed to pick up light irregularly reflected from a fingerprint surface of the finger contacted with said predetermined contact location.
Claim 15
Dependent Claim 42 words
A fingerprint input apparatus according to claim 12, wherein said lightguide plate is made of a tabular glass plate and is formed to have a light propagating length of about 100 mm and a width of about 30 mm to 40 mm.
Claim 16
Dependent Claim 35 words
A fingerprint input apparatus according to claim 12, wherein said means for directing the ray of light into at least one surface of said lightguide plate includes a prism having an isosceles triangle in section.
Claim 17
Dependent Claim 33 words
A fingerprint input apparatus according to claim 12, wherein said image pickup means is constructed to pick up the irregularly reflected light and to convert the irregularly reflected light into an electric signal.
Claim 18
Dependent Claim 192 words
A fingerprint input apparatus comprising: at least one light source for emitting a ray of light; a lightguide plate having a plurality of surfaces including a light-incident surface whereupon the ray of light is incident, a surface opposite the light-incident surface, a surface having a predetermined contact location provided thereon, and a surface opposite the surface having the predetermined contact location, the predetermined contact location being provided for a finger to be in contact therewith, the lightguide plate being constructed to totally reflect the light ray at least twice in the plate and to guide the ray of light within said lightguide plate into said predetermined contact location, the surface opposite the light-incident surface, the surface having the predetermined contact location provided thereon, and the surface opposite the surface having the predetermined contact location being formed by mirrors; and an image pickup means located near said predetermined contact location of said lightguide plate and outside the surface which is opposite the surface having the predetermined contact location, said image pickup means being constructed to pick up light irregularly reflected from a fingerprint surface of the finger contacted with said predetermined contact location.
Claim 19
Dependent Claim 192 words
A fingerprint input apparatus comprising: at least one light source for emitting a ray of light; a lightguide plate having a plurality of surfaces including a light-incident surface whereupon the ray of light is incident, a surface opposite the light-incident surface, a surface having a predetermined contact location provided thereon, and a surface opposite the surface having the predetermined contact location, the predetermined contact location being provided for a finger to be in contact therewith, the lightguide plate being constructed to totally reflect the light ray at least twice in the plate and to guide the ray of light within said lightguide plate into said predetermined contact location, the surface opposite the light-incident surface, the surface having the predetermined contact location provided thereon, and the surface opposite the surface having the predetermined contact location being formed by mirrors; and an image pickup means located near said predetermined contact location of said lightguide plate and outside the surface which is opposite the surface having the predetermined contact location, said image pickup means being constructed to pick up light irregularly reflected from a fingerprint surface of the finger contacted with said predetermined contact location.
Claim 20
Dependent Claim 42 words
A fingerprint input apparatus according to claim 16, wherein said lightguide plate is made of a tabular glass plate and is formed to have a light propagating length of about 100 mm and a width of about 30 mm to 40 mm.
Claim 21
Dependent Claim 33 words
A fingerprint input apparatus according to claim 16, wherein said image pickup means is constructed to pick up the irregularly reflected light and to convert the irregularly reflected light into an electric signal.
Claim 22
Dependent Claim 45 words
A fingerprint input apparatus according to claim 16, wherein a surface of said lightguide plate lit by said at least one light source is formed to keep a right angle of incidence of the ray of light emitted by said at least one light source.
Claim 23
Dependent Claim 39 words
A fingerprint input apparatus according to claim 16, wherein two light sources included in said at least one light source are constructed to respectively apply rays of light to both surfaces opposite to each other of said lightguide plate.
Claim 24
Dependent Claim 17 words
A fingerprint input apparatus according to claim 16, wherein said mirrors are made of a reflective metal.
Claim 25
Dependent Claim 15 words
A fingerprint input apparatus according to claim 21, wherein said mirrors are made of aluminum.

References Cited (Backward Citations)

US3975711A Cited
US4246568A Cited
US4569080A Cited
US4905293A Cited
JPS63156294A Cited
US4785171A Cited
US5077803A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1996-01-05 1996-07-06 1997-01-05 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2000-01-05 2000-07-06 2001-01-05 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2004-01-05 2004-07-06 2005-01-05 $7700.00 Window Closed / Lapsed

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