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US4669885A Expired / Lapsed US ⏱️ 0.0 years remaining

Apparatus for inspecting negatives

Assignee: Canon Inc
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Filing: 1983-03-17
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Granted: 1987-06-02
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Expires: 2003-03-17
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Abstract

Abstract Disclosed is an apparatus for inspecting negatives which is provided with a laser beam generating source, a scanner for scanning the laser beam, a holding device for holding a negative having a pattern formed in a reflective area on a first surface of a transparent plate and transferring the negative in a direction perpendicular to the scanning direction of the laser beam, a first converging lens for converging the laser beam on said first surface, a second converging lens for converging on a first photocell the beam transmitted through the negative, a third converging lens for converging on a second photocell the beam reflected by the first surface of the negative, and a comparator for comparing a first signal stream put out from the first photocell and a second signal stream put out from the second photocell and detecting an undesirable adhering matter.

Inventors

  • 👤 Hideki Ina

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 19:03
CPC Classifications
G; G03; G03F; G03F9/00; G03F9/70; H; H10; H10P; H10P95/00

Claims Analysis

Total Claims: 23
Claim 1
Independent Claim 184 words
An inspecting method comprising the steps of: holding a transparent body, a reflective pattern being formed on one of the opposed surfaces of said transparent body; producing radiant energy; applying said radiant energy from the side of said body on which said reflective pattern is not formed so as to cause said radiant energy to converge so that the convergency of said radiant energy is greater on the surface on which said reflective pattern is formed than on the surface on which said reflective pattern is not formed; moving the area irradiated with the radiant energy and said body relative to each other; receiving the radiant energy reflected by said pattern and producing a first output; receiving the radiant energy transmitted through said body and producing a second output; and discriminating that the radiant energy applied area includes defects, when said first output is smaller than an output to be obtained in the normal reflection of said radiant energy on said pattern and said output is smaller than an output to be obtained in the normal transparence of said radiant energy through said pattern.
Claim 2
Dependent Claim 184 words
An inspecting method comprising the steps of: holding a transparent body, a reflective pattern being formed on one of the opposed surfaces of said transparent body; producing radiant energy; applying said radiant energy from the side of said body on which said reflective pattern is not formed so as to cause said radiant energy to converge so that the convergency of said radiant energy is greater on the surface on which said reflective pattern is formed than on the surface on which said reflective pattern is not formed; moving the area irradiated with the radiant energy and said body relative to each other; receiving the radiant energy reflected by said pattern and producing a first output; receiving the radiant energy transmitted through said body and producing a second output; and discriminating that the radiant energy applied area includes defects, when said first output is smaller than an output to be obtained in the normal reflection of said radiant energy on said pattern and said output is smaller than an output to be obtained in the normal transparence of said radiant energy through said pattern.
Claim 3
Dependent Claim 13 words
An inspecting method according to claim 1, wherein said radiant energy is laser.
Claim 4
Dependent Claim 14 words
An inspecting method according to claim 2, wherein said laser has a P-polarization characteristic.
Claim 5
Dependent Claim 34 words
An inspecting method according to claim 1, wherein said step of discriminating includes a sample and hold step, an A/D converting step, a binary conversion step, and a step of forming the logical sum.
Claim 6
Dependent Claim 215 words
A mask aligner provided with; first holding means for holding a transparent negative, a reflective semiconductor circuit pattern being formed on one of the opposed surfaces of said transparent negative; beam producing means for producing an inspecting beam; projection means for projecting said inspecting beam from the side of said negative on which said pattern is not formed so as to cause said inspecting beam to converge so that the convergency of said inspecting beam is greater on the surface on which said pattern is formed that on the surface on which said pattern is not formed; second holding means for holding a recording carrier responsive to the projected image of said pattern; first detecting means for receiving the inspecting beam reflected by said negative; second detecting means for receiving the inspecting beam transmitted through said negative; and discriminating means for discriminating that a defect is included in the area to which said inspecting beam is applied, when an output of said first detecting means is smaller than an output of said first detecting means in the normal reflection of said inspecting beam on said pattern, and an output of said second detecting means is smaller than an output of said second detecting means in the normal transparence of said inspecting beam through said pattern.
Claim 7
Dependent Claim 215 words
A mask aligner provided with; first holding means for holding a transparent negative, a reflective semiconductor circuit pattern being formed on one of the opposed surfaces of said transparent negative; beam producing means for producing an inspecting beam; projection means for projecting said inspecting beam from the side of said negative on which said pattern is not formed so as to cause said inspecting beam to converge so that the convergency of said inspecting beam is greater on the surface on which said pattern is formed that on the surface on which said pattern is not formed; second holding means for holding a recording carrier responsive to the projected image of said pattern; first detecting means for receiving the inspecting beam reflected by said negative; second detecting means for receiving the inspecting beam transmitted through said negative; and discriminating means for discriminating that a defect is included in the area to which said inspecting beam is applied, when an output of said first detecting means is smaller than an output of said first detecting means in the normal reflection of said inspecting beam on said pattern, and an output of said second detecting means is smaller than an output of said second detecting means in the normal transparence of said inspecting beam through said pattern.
Claim 8
Independent Claim 179 words
An apparatus for inspecting defects included in a transparent body, a reflective pattern being formed on one of the opposed surfaces of said transparent body, comprising: projection means for projecting a beam from the side of said body on which said pattern is not formed so as to cause said beam to converge so that the convergency of said beam is greater on the surface on which said pattern is formed than on the surface on which said pattern is not formed; first detecting means for detecting the beam reflected by said pattern; second detecting means for detecting the beam transmitted through said body; and discriminating means for discriminating that a defect is included in the area to which said beam is applied, when an output of said first detecting means is smaller than an output of said first detecting means in the normal relection of said beam on said pattern, and an output of said second detecting means is smaller than an output of said second detecting means in the normal transparence of said beam through said pattern.
Claim 9
Independent Claim 179 words
An apparatus for inspecting defects included in a transparent body, a reflective pattern being formed on one of the opposed surfaces of said transparent body, comprising: projection means for projecting a beam from the side of said body on which said pattern is not formed so as to cause said beam to converge so that the convergency of said beam is greater on the surface on which said pattern is formed than on the surface on which said pattern is not formed; first detecting means for detecting the beam reflected by said pattern; second detecting means for detecting the beam transmitted through said body; and discriminating means for discriminating that a defect is included in the area to which said beam is applied, when an output of said first detecting means is smaller than an output of said first detecting means in the normal relection of said beam on said pattern, and an output of said second detecting means is smaller than an output of said second detecting means in the normal transparence of said beam through said pattern.
Claim 10
Dependent Claim 27 words
An inspecting apparatus according to claim 6, wherein said discriminating means comprises means for taking the sum of the outputs of said first and second detecting means.
Claim 11
Dependent Claim 28 words
An inspecting apparatus according to claim 7, wherein said discriminating means further comprises means for converting the outputs of said first and second detecting means to digital form.
Claim 12
Dependent Claim 31 words
An inspecting apparatus according to claim 8, wherein said discriminating means carries out the discrimination on the basis of the sum of digitalized outputs of said first and second detecting means.
Claim 13
Dependent Claim 18 words
An inspecting apparatus according to claim 6, wherein said projecting means scans the beam relative to said body.
Claim 14
Dependent Claim 22 words
An inspecting apparatus according to claim 10, wherein said projecting means scans the beam relative to said body at a constant speed.
Claim 15
Dependent Claim 18 words
An inspecting apparatus according to claim 11, wherein said projecting means obliquely projects the beam to said body.
Claim 16
Dependent Claim 24 words
An inspecting apparatus according to claim 12, wherein said projecting means comprises means for correcting the aberrations of the converged point of the beam.
Claim 17
Dependent Claim 16 words
An inspecting apparatus according to claim 13, wherein said projecting means projects a linearly polarized beam.
Claim 18
Dependent Claim 15 words
An inspecting apparatus according to claim 14, wherein said projecting means projects a P-polarized beam.
Claim 19
Dependent Claim 15 words
An inspecting apparatus according to claim 15, wherein said projecting means projects a laser beam.
Claim 20
Dependent Claim 18 words
An inspecting apparatus according to claim 6, wherein said body is used during the manufacturing of a semiconductor.
Claim 21
Dependent Claim 19 words
An inspecting apparatus according to claim 6, wherein said body moves in a predetermined direction relative to the beam.
Claim 22
Dependent Claim 26 words
An inspecting apparatus according to claim 18, wherein said projecting means scans the beam in a direction different from that of the movement of said body.
Claim 23
Dependent Claim 30 words
An inspecting apparatus according to claim 19, wherein at least one of said first and second detecting means comprises a sensor array arranged in the direction of said beam scan.

References Cited (Backward Citations)

GB988014A Cited
US3632226A Cited
US3693021A Cited
US3746869A Cited
US3734624A Cited
US3877821A Cited
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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-06-01 1990-12-01 1991-06-02 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-06-01 1994-12-01 1995-06-02 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-06-01 1998-12-01 1999-06-02 $7700.00 Window Closed / Lapsed

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