Patent US5202749A successfully refreshed from Google Patents.
US5202749A
Expired / Lapsed
US
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Process and device for observing moire patterns of surfaces to be tested by application of the moire method using phase shifting
Assignee: Individual
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Filing: 1989-12-22
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Granted: 1993-04-13
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Expires: 2009-12-22
Abstract
Abstract The object of the invention is a process for observing moire patterns of surfaces to be tested, wherein the object gratings to be observed are pictured onto auxiliary gratings and the moire patterns generated thereby are detected, stored and/or processed by computer, wherein for each observation at least phase-shifted moire patterns are respectively evaluated. Furthermore, the invention relates to a device for observing moire patterns of the surfaces to be tested by applying the moire method using phase shifting. For an observation of the phase-shifted moire patterns associated with the object grating are simultaneously generated, pictured and detected by superposition of the object grating image with auxiliary gratings which are disposed in a phase-shifted manner.
Inventors
- 👤 Klaus Pfister
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 10:28
CPC Classifications
G; G01; G01B; G01B11/00; G01B11/24; G01B11/25; G01B11/254
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
189 words
A device for observing moire patterns of surfaces to be tested, said device applying the moire method by phase shifting, comprising: observation objective means for receiving an object grating emitted from the object in the form of a picturing path of rays; a first auxiliary grating for generating a moire pattern from the picturing path of rays; camera means for observing the moire pattern generated from the picturing path of rays; means for storing and/or evaluating the observed moire pattern generated from the picturing path of rays, said storing means connected to said camera means; wherein the improvement comprises: at least two additional auxiliary gratings, said second and third auxiliary gratings positioned near said first auxiliary grating with all of said auxiliary gratings adjustably positioned in the path of the rays, between said observation objective means and said camera means, so as to be in a phase-shifted relationship to each other by a corresponding phase angle, each of said at least three auxiliary gratings generating a phase-shifted moire pattern; and said camera means respectively detecting the phase-shifted moire patterns simultaneously from each of the at least three auxiliary gratings.
Claim 2
Independent Claim
189 words
A device for observing moire patterns of surfaces to be tested, said device applying the moire method by phase shifting, comprising: observation objective means for receiving an object grating emitted from the object in the form of a picturing path of rays; a first auxiliary grating for generating a moire pattern from the picturing path of rays; camera means for observing the moire pattern generated from the picturing path of rays; means for storing and/or evaluating the observed moire pattern generated from the picturing path of rays, said storing means connected to said camera means; wherein the improvement comprises: at least two additional auxiliary gratings, said second and third auxiliary gratings positioned near said first auxiliary grating with all of said auxiliary gratings adjustably positioned in the path of the rays, between said observation objective means and said camera means, so as to be in a phase-shifted relationship to each other by a corresponding phase angle, each of said at least three auxiliary gratings generating a phase-shifted moire pattern; and said camera means respectively detecting the phase-shifted moire patterns simultaneously from each of the at least three auxiliary gratings.
Claim 3
Dependent Claim
32 words
The device according to claim 1, wherein said object grating and said at least three auxiliary gratings are two-fold and arranged in an angular manner and provide crossed line gratings for measuring.
Claim 4
Dependent Claim
17 words
The device according to claim 2, wherein said crossed line gratings are positioned vertical to each other.
Claim 5
Dependent Claim
47 words
The device according to claim 1, wherein a plurality of beam splitters are positioned between said object grating and said at least three auxiliary gratings in the path of the picturing ray, said plurality of beam splitters splitting the picturing ray into at least three partial beams.
Claim 6
Dependent Claim
17 words
The device according to claim 4, wherein said plurality of beam splitters are splitting plates or prisms.
Claim 7
Dependent Claim
25 words
The device according to claim 5, wherein a colour filter is positioned in the path of the picturing rays before the plurality of beam splitters.
Claim 8
Dependent Claim
67 words
The device of claim 1, wherein one of said at least three auxiliary gratings includes a plurality of sensor arrays for producing line or column pitch wherein the pitch is at least threefold of the pitch required for producing a moire pattern; and reading means for resolving the lines or columns of the auxiliary grating pattern as lines or columns of the at least three phase-shifted patterns.
Claim 9
Dependent Claim
22 words
The device of claim 1, wherein said at least three auxiliary gratings generating a single line or column for the moire pattern.
Claim 10
Dependent Claim
22 words
The device of claim 1, wherein said at least three auxiliary gratings include sensors positioned and being effective in a grating-line manner.
Claim 11
Dependent Claim
19 words
The device of claim 9, wherein at least one of said three auxiliary gratings includes a CCD camera array.
Claim 12
Dependent Claim
18 words
The device of claim 1, wherein at least one of said three auxiliary gratings includes a microchannel plate.
Claim 13
Dependent Claim
13 words
The device of claim 1, wherein said camera means includes a video camera.
Claim 14
Dependent Claim
14 words
The device of claim 1, wherein said camera means includes a drum type camera.
Claim 15
Dependent Claim
18 words
The device of claim 1, wherein said object grating is fixedly applied to the surfaces to be tested.
Claim 16
Dependent Claim
13 words
The device of claim 1, wherein said object grating includes a projection arrangement.
Claim 17
Independent Claim
171 words
A method for observing moire patterns of surfaces to be tested, said method applying the moire method by phase-shifting, comprising the steps of: receiving an object grating in the form of a picturing path of rays emitted from the object surface; generating by means of a first auxiliary grating a moire pattern from the picturing path of rays; observing the moire pattern generated from the picturing path of rays; storing and/or evaluating the observed moire pattern generated from the picturing path of rays; wherein the improvement comprises the steps of: positioning at least two additional auxiliary gratings near said first auxiliary grating in the picturing path of the rays, wherein each auxiliary grating is in a phase-shifted relationship; generating a plurality of moire patterns by said at least two additional auxiliary gratings simultaneously together with said generated moire pattern by said first auxiliary grating; detecting at least three phase-shifted moire patterns simultaneously generated; and evaluating said at least three phase-shifted moire patterns simultaneously detected by superposition of an object generating image.
Claim 18
Independent Claim
171 words
A method for observing moire patterns of surfaces to be tested, said method applying the moire method by phase-shifting, comprising the steps of: receiving an object grating in the form of a picturing path of rays emitted from the object surface; generating by means of a first auxiliary grating a moire pattern from the picturing path of rays; observing the moire pattern generated from the picturing path of rays; storing and/or evaluating the observed moire pattern generated from the picturing path of rays; wherein the improvement comprises the steps of: positioning at least two additional auxiliary gratings near said first auxiliary grating in the picturing path of the rays, wherein each auxiliary grating is in a phase-shifted relationship; generating a plurality of moire patterns by said at least two additional auxiliary gratings simultaneously together with said generated moire pattern by said first auxiliary grating; detecting at least three phase-shifted moire patterns simultaneously generated; and evaluating said at least three phase-shifted moire patterns simultaneously detected by superposition of an object generating image.
Claim 19
Dependent Claim
26 words
The method of claim 16, wherein the phase shift of the auxiliary gratings further comprises the step of: providing two directions preferably vertical to each other.
Claim 20
Dependent Claim
60 words
The method of claim 16, wherein the step of generating the phase-shifted moire patterns further comprises the steps of: picturing the object grating by means of at least three partial beams onto said at lest three auxiliary gratings; arranging said at least three auxiliary gratings in a phase-shifted manner to each other; and detecting the generated phase-shifted moire patterns simultaneously.
Claim 21
Dependent Claim
61 words
The method of claim 16, further comprising the steps of: generating the phase-shifted moire patterns by picturing the object grating by means of a beam onto the auxiliary grating; packing the at least three auxiliary gratings for generating at least threefold scaling; detecting the single phase-shifted moire patterns; reading the moire patterns by interleaving each other from the auxiliary gratings line-by-line/column-by-column.
Claim 22
Dependent Claim
19 words
The method of claim 16, further comprising the step of: picturing only onto one auxiliary grating line or column.
Claim 23
Dependent Claim
50 words
The method of claim 16, wherein the step of generating further comprises the steps of: observing at least three object gratings having a different colour; and detecting arranged phase-shifted and single phase shifted moire patterns by separating the moire pattern packed together of the object grating images selectively in colour.
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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) | 1996-04-12 | 1996-10-12 | 1997-04-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-04-12 | 2000-10-12 | 2001-04-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-04-12 | 2004-10-12 | 2005-04-13 | $7700.00 | Window Closed / Lapsed |