US5568258A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and device for measuring distortion of a transmitting beam or a surface shape of a three-dimensional object
Assignee: AGC Inc
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Filing: 1995-04-25
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Granted: 1996-10-22
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Expires: 2015-04-25
Abstract
Abstract A method of measuring a distortion of a transmitting beam, characterized in that a transmitting beam is emitted from a beam generator and projected onto a screen as a bright spot, the bright spot is scanned over a surface of the screen, and a distortion of the transmitting beam is measured on the basis of a distance between a first location of the bright spot on the screen at a first time when the transmitting beam is incident on a beam receiving device in a specified incident direction upon transmitting through a measured body, and a second location of the bright spot on the screen at a second time when the transmitting beam is incident on the beam receiving device in the specified incident direction upon not transmitting through the measured body. A surface shape of a three-dimensional object may also be measured on the basis of a distance between a first location of the bright spot on the screen at a first time when the transmitting beam is incident on a beam receiving device in a specified incident direction upon being reflected from a surface of a three-dimensional measured body, and a second location of the bright spot on the screen at a second time when the transmitting beam is incident on the beam receiving device in the specified incident direction upon being reflected from a surface of a reference body. The present invention provides measurements having improved accuracy for objects of any size irrespective of the resolution of the beam receiving device.
Inventors
- 👤 Ken Uemura
- 👤 Yukiko Nagashima
- 👤 Yasunari Saito
- 👤 Takao Kurita
- 👤 Tetsuo Miyake
- 👤 Kazuaki Shimizu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-10 01:31
CPC Classifications
G; G01; G01B; G01B11/00; G01B11/24
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
286 words
A method of measuring a distortion of a transmitting beam, characterized in that: a transmitting beam is emitted from a beam generator and projected onto a screen as a bright spot; said bright spot is scanned over a surface of said screen; a beam receiving device is provided with a beam receiving plane comprising a plurality of pixels and brightness distribution curves are generated for each of said plurality of pixels of said beam receiving device by measuring and recording a degree of brightness detected at each of said plurality of pixels during each time period when said bright spot changes position while scanning over said surface of said screen and selecting a representative point representing a degree of brightness on a brightness distribution curve corresponding to each of said plurality of pixels; a first location of said bright spot on said screen is determined at a first time when a measured degree of brightness at a given one of said plurality of pixels is equal to a degree of brightness represented by a representative point on a brightness distribution curve corresponding to said given one of said plurality of pixels upon transmitting through a measured body, and a second location of said bright spot on said screen is determined at a second time when a measured degree of brightness at said given one of said plurality of pixels is equal to a degree of brightness represented by a representative point on a brightness distribution curve corresponding to said given one of said plurality of pixels upon not transmitting through said measured body; and a distortion of said transmitting beam is measured on the basis of a distance between said first location and said second location.
Claim 2
Independent Claim
286 words
A method of measuring a distortion of a transmitting beam, characterized in that: a transmitting beam is emitted from a beam generator and projected onto a screen as a bright spot; said bright spot is scanned over a surface of said screen; a beam receiving device is provided with a beam receiving plane comprising a plurality of pixels and brightness distribution curves are generated for each of said plurality of pixels of said beam receiving device by measuring and recording a degree of brightness detected at each of said plurality of pixels during each time period when said bright spot changes position while scanning over said surface of said screen and selecting a representative point representing a degree of brightness on a brightness distribution curve corresponding to each of said plurality of pixels; a first location of said bright spot on said screen is determined at a first time when a measured degree of brightness at a given one of said plurality of pixels is equal to a degree of brightness represented by a representative point on a brightness distribution curve corresponding to said given one of said plurality of pixels upon transmitting through a measured body, and a second location of said bright spot on said screen is determined at a second time when a measured degree of brightness at said given one of said plurality of pixels is equal to a degree of brightness represented by a representative point on a brightness distribution curve corresponding to said given one of said plurality of pixels upon not transmitting through said measured body; and a distortion of said transmitting beam is measured on the basis of a distance between said first location and said second location.
Claim 3
Dependent Claim
46 words
The method of measuring a distortion of a transmitting beam according to claim 1, wherein said bright spot scanning over said surface of said screen is produced by a laser beam generated by said beam generator, and said surface of said screen approximately forms a plane.
Claim 4
Independent Claim
295 words
A method of measuring a surface shape of a three-dimensional object, characterized in that: a transmitting beam is emitted from a beam generator and projected onto a screen as a bright spot; said bright spot is scanned over a surface of said screen; a beam receiving device is provided with a beam receiving plane comprising a plurality of pixels and brightness distribution curves are generated for each of said plurality of pixels of said beam receiving device by measuring and recording a degree of brightness detected at each of said plurality of pixels during each time period when said bright spot changes position while scanning over said surface of said screen and selecting a representative point representing a degree of brightness on a brightness distribution curve corresponding to each of said plurality of pixels; a first location of said bright spot on said screen is determined at a first time when a measured degree of brightness at a given one of said plurality of pixels is equal to a degree of brightness represented by a representative point on a brightness distribution curve corresponding to said given one of said plurality of pixels upon being reflected from a surface of said three-dimensional object, and a second location of said bright spot on said screen is determined that a second time when a measured degree of brightness at said given one of said plurality of pixels is equal to a degree of brightness represented by a representative point on a brightness distribution curve corresponding to said given one of said plurality of pixels upon being reflected from a surface of a reference body; and a surface shape of said three-dimensional object is measured on the basis of a distance between said first location and said second location.
Claim 5
Independent Claim
295 words
A method of measuring a surface shape of a three-dimensional object, characterized in that: a transmitting beam is emitted from a beam generator and projected onto a screen as a bright spot; said bright spot is scanned over a surface of said screen; a beam receiving device is provided with a beam receiving plane comprising a plurality of pixels and brightness distribution curves are generated for each of said plurality of pixels of said beam receiving device by measuring and recording a degree of brightness detected at each of said plurality of pixels during each time period when said bright spot changes position while scanning over said surface of said screen and selecting a representative point representing a degree of brightness on a brightness distribution curve corresponding to each of said plurality of pixels; a first location of said bright spot on said screen is determined at a first time when a measured degree of brightness at a given one of said plurality of pixels is equal to a degree of brightness represented by a representative point on a brightness distribution curve corresponding to said given one of said plurality of pixels upon being reflected from a surface of said three-dimensional object, and a second location of said bright spot on said screen is determined that a second time when a measured degree of brightness at said given one of said plurality of pixels is equal to a degree of brightness represented by a representative point on a brightness distribution curve corresponding to said given one of said plurality of pixels upon being reflected from a surface of a reference body; and a surface shape of said three-dimensional object is measured on the basis of a distance between said first location and said second location.
Claim 6
Dependent Claim
47 words
The method of measuring a surface shape of a three-dimensional object according to claim 3, wherein said bright spot scanning over said surface of said screen is produced by a laser beam generated by said beam generator, and said surface of said screen approximately forms a plane.
Claim 7
Independent Claim
314 words
A device for measuring a distortion of a transmitting beam or a surface shape of a three-dimensional object, comprising: beam emitting means for emitting a transmitting beam, projecting said transmitting beam onto a screen as a bright spot, and scanning said bright spot over a surface of said screen; beam receiving means having a plurality of pixels, wherein brightness distribution curves are generated for each of said plurality of pixels of said beam receiving device by measuring and recording a degree of brightness detected at each of said plurality of pixels during each time period when said bright spot changes position while scanning over said surface of said screen and selecting a representative point representing a degree of brightness on a distribution curve corresponding to each of said plurality of pixels; support means for supporting said three-dimensional object and maintaining said three-dimensional object in a path of said transmitting beam between said screen and said beam receiving means; and calculating means for calculating a distortion of said transmitting beam or a surface shape of said three-dimensional object on the basis of a distance between a first location of said bright spot on said screen determined at a first time when a measured degree of brightness at a given one of said plurality of pixels is equal to a degree of brightness represented by a representative point on a brightness distribution curve corresponding to said given one of said plurality of pixels upon being deviated by said three-dimensional object, and a second location of said bright spot on said screen determined at a second time when a measured degree of brightness at said given one of said plurality of pixels is equal to a degree of brightness represented by a representative point on a brightness distribution curve corresponding to said given one of said plurality of pixels upon not being deviated by said three-dimensional object.
Claim 8
Independent Claim
314 words
A device for measuring a distortion of a transmitting beam or a surface shape of a three-dimensional object, comprising: beam emitting means for emitting a transmitting beam, projecting said transmitting beam onto a screen as a bright spot, and scanning said bright spot over a surface of said screen; beam receiving means having a plurality of pixels, wherein brightness distribution curves are generated for each of said plurality of pixels of said beam receiving device by measuring and recording a degree of brightness detected at each of said plurality of pixels during each time period when said bright spot changes position while scanning over said surface of said screen and selecting a representative point representing a degree of brightness on a distribution curve corresponding to each of said plurality of pixels; support means for supporting said three-dimensional object and maintaining said three-dimensional object in a path of said transmitting beam between said screen and said beam receiving means; and calculating means for calculating a distortion of said transmitting beam or a surface shape of said three-dimensional object on the basis of a distance between a first location of said bright spot on said screen determined at a first time when a measured degree of brightness at a given one of said plurality of pixels is equal to a degree of brightness represented by a representative point on a brightness distribution curve corresponding to said given one of said plurality of pixels upon being deviated by said three-dimensional object, and a second location of said bright spot on said screen determined at a second time when a measured degree of brightness at said given one of said plurality of pixels is equal to a degree of brightness represented by a representative point on a brightness distribution curve corresponding to said given one of said plurality of pixels upon not being deviated by said three-dimensional object.
Claim 9
Dependent Claim
54 words
The device for measuring distortion of a transmitting beam or a surface shape of a three-dimensional object according to claim 5, wherein said bright spot scanning over said surface of said screen is produced by a laser beam generated by said beam emitting means, and said surface of said screen approximately forms a plane.
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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) | 1999-10-22 | 2000-04-22 | 2000-10-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-10-22 | 2004-04-22 | 2004-10-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-10-22 | 2008-04-22 | 2008-10-22 | $7700.00 | Window Closed / Lapsed |