Patent US3883249A successfully refreshed from Google Patents.
US3883249A
Expired / Lapsed
US
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Z-factor and other diffractographic displacement and profile sensors
Assignee: Sensor Adaptive Machines Inc
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Filing: 1973-05-09
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Granted: 1975-05-13
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Expires: 1993-05-09
Abstract
Abstract Disclosed are a method and devices for determining the relative position of two boundaries by analyzing the interference pattern produced by diffraction waves created when a laser beam irradiates the boundaries.
Inventors
- 👤 Timothy R Pryor
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 14:29
CPC Classifications
G; G01; G01B; G01B11/00; G01B11/24; G01B11/2433; G01B11/02; G01B11/06; G01B11/0616; G01B11/0675
Claims Analysis
Total Claims: 43
Claim 1
Independent Claim
112 words
A method of determining the relative position of at least two boundaries comprising the steps of: directing electromagnetic waves onto at least one first boundary to produce a first diffraction wave; directing electromagnetic waves onto at least one second boundary to produce a second diffraction wave, said second boundary being spaced from said first boundary in the direction of propagation of said electromagnetic waves, said first and second diffraction waves interacting to produce an interference pattern; and determining from said interference pattern the relative position of said first and second boundaries, in a direction transverse to said direction of propagation, or in said direction of propagation, or in both of said directions.
Claim 2
Independent Claim
112 words
A method of determining the relative position of at least two boundaries comprising the steps of: directing electromagnetic waves onto at least one first boundary to produce a first diffraction wave; directing electromagnetic waves onto at least one second boundary to produce a second diffraction wave, said second boundary being spaced from said first boundary in the direction of propagation of said electromagnetic waves, said first and second diffraction waves interacting to produce an interference pattern; and determining from said interference pattern the relative position of said first and second boundaries, in a direction transverse to said direction of propagation, or in said direction of propagation, or in both of said directions.
Claim 3
Dependent Claim
15 words
A method according to claim 1 wherein one of said boundaries comprises a moving surface.
Claim 4
Dependent Claim
17 words
A method according to claim 2 wherein said moving surface is a surface of a sheet material.
Claim 5
Dependent Claim
16 words
A method according to claim 3 wherein said sheet material is moved over a curved surface.
Claim 6
Dependent Claim
15 words
A method according to claim 4 wherein said curved surface comprises a rotatable cylindrical roller.
Claim 7
Dependent Claim
32 words
A method according to claim 5 wherein the position of said curved surface relative to said boundary not comprised by a moving sheet is known such that sheet thickness may be determined.
Claim 8
Dependent Claim
34 words
A method according to claim 4 wherein the position of said sheet surface boundary relative to the other boundary is known such that the thickness of a coating on said sheet may be determined.
Claim 9
Dependent Claim
16 words
A method according to claim 1 wherein said first and second boundaries are on single member.
Claim 10
Dependent Claim
15 words
A method according to claim 1 wherein said electromagnetic waves are produced by a laser.
Claim 11
Dependent Claim
25 words
A method according to claim 1 wherein the boundary more remote from the source of electromagnetic waves comprises a material transparent to said electromagnetic waves.
Claim 12
Dependent Claim
49 words
A method according to claim 1 wherein changes in relative position of said boundaries are determined from the interference pattern using two detectors each at the same angular position relative to the axis of the direction of propagation of electromagnetic waves but located on opposite sides of said axis.
Claim 13
Dependent Claim
44 words
A method according to claim 11 wherein said boundaries each lie on a separate member and each member is spaced in said direction of propagation a distance such that fringe positions at each of said detectors are 90* out of phase with each other.
Claim 14
Dependent Claim
23 words
A method according to claim 1 wherein the path of said electromagnetic waves is deviated prior to production of said second diffraction wave.
Claim 15
Dependent Claim
34 words
A method according to claim 3 wherein said electromagnetic waves produce diffraction waves from an elongate region of said sheet material and said waves are focused to form essentially a unitary average interference pattern.
Claim 16
Dependent Claim
34 words
A method according to claim 3 wherein a multiplicity of separate patterns are produced corresponding to the relative position of various portions of the sheet relative to positions on one or more other boundaries.
Claim 17
Dependent Claim
25 words
A method according to claim 1 wherein said waves are sequentially directed to a plurality of locations across the length of one of said boundaries.
Claim 18
Dependent Claim
29 words
A method according to claim 1 wherein said electromagnetic waves are directed onto a continuum of first and second boundary locations to produce a continuum of adjacent interference patterns.
Claim 19
Dependent Claim
25 words
A method according to claim 1 wherein electromagnetic waves are directed onto a continuum of first boundary locations and essentially a single second boundary location.
Claim 20
Dependent Claim
40 words
A method according to claim 1 wherein said first and second diffraction waves emanate in a plane and wherein said first and second boundaries are spaCed in a direction making a non-zero angle with the plane of the diffracted waves.
Claim 21
Independent Claim
110 words
A method of determining the relative position of at least two boundaries comprising the steps of: directing electromagnetic waves onto at least one first boundary to produce a first diffraction wave, said first wave emanating in a plane; directing electromagnetic waves onto at least one second boundary to produce a second diffraction wave, said second wave emanating in a plane, said second boundary being spaced in a direction making a non-zero angle with the planes of the waves diffracted from said boundaries; causing said first and second waves to interact to produce an interference pattern; and determining from said interference pattern the relative position of said first and second boundaries.
Claim 22
Independent Claim
110 words
A method of determining the relative position of at least two boundaries comprising the steps of: directing electromagnetic waves onto at least one first boundary to produce a first diffraction wave, said first wave emanating in a plane; directing electromagnetic waves onto at least one second boundary to produce a second diffraction wave, said second wave emanating in a plane, said second boundary being spaced in a direction making a non-zero angle with the planes of the waves diffracted from said boundaries; causing said first and second waves to interact to produce an interference pattern; and determining from said interference pattern the relative position of said first and second boundaries.
Claim 23
Dependent Claim
114 words
Apparatus for determining the relative position of at least two boundaries comprising: means for directing electromagnetic waves onto at least one first boundary to produce a first diffraction wave; means for directing electromagnetic waves onto at least one second boundary to produce a second diffraction wave, said second boundary being spaced from said first boundary in the direction of propagation of said electromagnetic waves, said first and second diffraction waves interacting to produce an interference pattern; and means for determining from said interference pattern the relative position of said first and second boundaries, in a direction transverse to said direction of propagation, or in said direction of propagation, or in both of said directions.
Claim 24
Dependent Claim
114 words
Apparatus for determining the relative position of at least two boundaries comprising: means for directing electromagnetic waves onto at least one first boundary to produce a first diffraction wave; means for directing electromagnetic waves onto at least one second boundary to produce a second diffraction wave, said second boundary being spaced from said first boundary in the direction of propagation of said electromagnetic waves, said first and second diffraction waves interacting to produce an interference pattern; and means for determining from said interference pattern the relative position of said first and second boundaries, in a direction transverse to said direction of propagation, or in said direction of propagation, or in both of said directions.
Claim 25
Dependent Claim
14 words
Apparatus according to claim 21 wherein said electromagnetic waves are produced by a laser.
Claim 26
Dependent Claim
16 words
Apparatus according to claim 21 including photodetector means for detecting a portion of said interference pattern.
Claim 27
Dependent Claim
16 words
Apparatus according to claim 23 wherein said photodetector means comprises a pair of closely spaced photocells.
Claim 28
Dependent Claim
33 words
Apparatus according to claim 21 including scanning means for determining fringe positions in said interference pattern, said scanning means comprising a plurality of photosensing elements reponsive to the wavelength of electromagnetic radiation used.
Claim 29
Dependent Claim
13 words
Apparatus according to claim 25 wherein said scanning means comprises a photodiode array.
Claim 30
Dependent Claim
13 words
Apparatus according to claim 25 wherein said scanning means comprises a television camera.
Claim 31
Dependent Claim
38 words
Apparatus according to claim 21 including two photodetector means each being located at the same angular position relative to the axis of the directon of propagation of said electromagnetic waves, but located on opposite sides of said axis.
Claim 32
Dependent Claim
22 words
Apparatus according to claim 21 including means for adjustably moving one of said boundaries a known distance relative to the other boundary.
Claim 33
Dependent Claim
25 words
Apparatus according to claim 21 including means for sequentially directing electromagnetic waves to a plurality of locations across the length of one of said boundaries.
Claim 34
Dependent Claim
14 words
Apparatus according to claim 21 including a cylinder lens for diverging said electromagnetic waves.
Claim 35
Dependent Claim
108 words
Apparatus for determining the relative position of at least two boundaries comprising: means for directing electromagnetic waves onto at least one first boundary to produce a first diffraction wave emanating in a plane; means for directing electromagnetic waves onto at least one second boundary to produce a second diffraction wave emanating in a plane, said second boundary being spaced in a direction making a non-zero angle with the plane of the waves diffracted from said boundaries; means for causing said first and second waves to interact to produce an interference pattern; and means for determining from said interference pattern the relative position of said first and second boundaries.
Claim 36
Dependent Claim
108 words
Apparatus for determining the relative position of at least two boundaries comprising: means for directing electromagnetic waves onto at least one first boundary to produce a first diffraction wave emanating in a plane; means for directing electromagnetic waves onto at least one second boundary to produce a second diffraction wave emanating in a plane, said second boundary being spaced in a direction making a non-zero angle with the plane of the waves diffracted from said boundaries; means for causing said first and second waves to interact to produce an interference pattern; and means for determining from said interference pattern the relative position of said first and second boundaries.
Claim 37
Dependent Claim
40 words
A method according to claim 1 wherein said first and second boundaries are separated a known distance in the direction of propagation of said electromagnetic waves and wherein the relative position of said boundaries in said transverse Direction is determined.
Claim 38
Dependent Claim
45 words
A method according to claim 1 wherein said first and second boundaries are separated a known distance in a direction transverse to the direction of propagation of said electromagnetic waves and wherein the relative position of said boundaries in said direction of propagation is determined.
Claim 39
Dependent Claim
42 words
A method according to claim 1 wherein said first and second boundaries are separated a fixed distance in the direction of propagation of said electromagnetic waves and wherein change in the relative position of said boundaries in said transverse direction is determined.
Claim 40
Dependent Claim
40 words
A method according to claim 1 wherein said first and second boundaries are separated a fixed distance in a direction transverse to the direction of propagation of said electromagnetic waves and wherein change in the direction of propagation is determined.
Claim 41
Dependent Claim
52 words
A metal according to claim 1 including the step of detecting the intensity of electromagnetic radiation in said interference pattern with detection means located at a fixed distance from the axis of said interference pattern to detect a portion of the interference pattern, and determining said relative position from said detected intensity.
Claim 42
Dependent Claim
27 words
Apparatus according to claim 21 further including means for fixing the position of said first and second boundaries in the direction of propagation of said electromagnetic radiation.
Claim 43
Dependent Claim
31 words
Apparatus according to claim 21 further including means for fixing the position of said first and second boundaries in a direction transverse to the direction of propagation of said electromagnetic radiation.
References Cited (Backward Citations)
US3518007A
Cited
US3709610A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-05-12 | 1978-11-11 | 1979-05-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-12 | 1982-11-11 | 1983-05-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-12 | 1986-11-11 | 1987-05-13 | $7700.00 | Window Closed / Lapsed |