Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
158 words
An optical apparatus for a fingerprint recognition system comprising: a light source for emitting a spherical beam, a collimating hologram for reproducing a plane beam upon receiving the emitted spherical beam from said light source, a diffuser for obtaining a scattered beam by scattering the plane beam from said collimating hologram, a triangular prism for absorbing the scattered beam at ridges but reflecting the scattered beam at valleys of subject fingerprint upon receiving said scattered beam from said diffuser, a fingerprint image producing hologram for processing the reflected spherical beam from said prism at the valleys and then condensing a spherical beam representing the subject fingerprint upon an area CCD for producing the subject fingerprint image thereon, the area CCD for converting the produced fingerprint image into an electric signal, and said triangular prism including said fingerprint image producing hologram and a cutoff/absorption plate for cutting off and absorbing the beam, respectively mounted at a vertical surface thereof.
Claim 2
Dependent Claim
92 words
The optical apparatus according to claim 1, wherein said collimating hologram is mounted as located at an angle of ⊖3 in a distance of Lo from said light source, and made as located at a location wherein at a center point C2 thereof a spherical beam as a reference beam emitted from a spherical beam scanning point P1 located in a distance of ℓo from said center point C2 crosses with a plane beam as an object beam, at an angle of ⊖4, and wherein ⊖4 = ⊖3, and Lo = ℓo.
Claim 3
Dependent Claim
102 words
The optical apparatus according to claim 1, wherein said fingerprint image producing hologram is mounted at a location of said prism with an angle ⊖1 in a distance of L1 from a center point Co of said slant surface of said prism, and said area CCD is located at a location with an angle of ⊖2 in a distance of L2 from a center point C1 of said image producing hologram 5, and the following conditions are satisfied. ⊖1 = ⊖2, 25° < ⊖1, ⊖2 < 35°, and L1 cos⊖1 = 2n L2 cos⊖2 (n: a refractive index of said triangular prism).
Claim 4
Dependent Claim
112 words
The optical apparatus according to claim 3, wherein said fingerprint image producing hologram is a hologram made as locating at a location wherein at a center point C3 of said hologram a spherical beam as a reference beam, emitted from a spherical beam scanning point P2 in a distance of ℓ1 from the center point C3 crosses at an angle of ⊖5 + ⊖6 with a condensed spherical beam condensed at a beam condensing point P3 in a distance of ℓ2 from the center point C3, and the following conditions are satisfied, ⊖1 = ⊖5, ⊖2 = ⊖6, L1 = nℓ1, L2 = ℓ2, and 25° < ⊖5 and ⊖6 < 35°.
Claim 5
Dependent Claim
19 words
The optical apparatus according to claim 1, wherein said light source is a laser for emitting a laser beam.