US3768911A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electro-optical incremental motion and position indicator
Assignee: Cubic Corp
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Filing: 1971-08-17
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Granted: 1973-10-30
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Expires: 1991-08-17
Abstract
Abstract A compact electro-optical system provides electrical signals for indicating extent and direction of incremental movement. By employing a plurality of moire fringe-generating grating pairs in optical series, the system eliminates the need for a collimated light source or imaging optics, and further provides a multiplication of sensitivity.
Inventors
- 👤 K Erickson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:58
CPC Classifications
G; G01; G01D; G01D5/00; G01D5/26; G01D5/32; G01D5/34; G01D5/36; G01D5/38
Claims Analysis
Total Claims: 31
Claim 1
Independent Claim
251 words
A method of creating an electrical signal varying as a function of physical displacement which comprises: a. arranging a light source and two pairs of amplitude grating patterns in sequence along an optical axis, the grid rulings comprising said grating patterns being substantially parallel and in parallel planes disposed substantially perpendicular to said axis, the grating patterns comprising each of said grating pattern pairs being spaced apart by a distance substantially equal to d2/ lambda ; where d is the grating pattern period and lambda is the effective wavelength of light from said source, said spacing thereby establishing a series of directional light transmission preferences varying cyclically in a direction transverse to said grid rulings; b. directing a beam of substantially omnidirectional light from said source through said two pairs of grating patterns along said optical axis to incidence upon photoelectric means capable of providing an electrical signal varying as a function of the intensity of light from said source incident thereupon, said photoelectric means having a field of view with respect to said light source inclusive of a plurality of cycles in said directional light transmission preference series; and c. displacing at least one of said grating patterns with respect to its pair-mate grating pattern in a direction transverse to said grid rulings, thereby effecting a variation in the intensity of the light transmitted through said two pairs of grating patterns and incident upon said photoelectric means as a function of the displacement of said at least one grating pattern.
Claim 2
Independent Claim
251 words
A method of creating an electrical signal varying as a function of physical displacement which comprises: a. arranging a light source and two pairs of amplitude grating patterns in sequence along an optical axis, the grid rulings comprising said grating patterns being substantially parallel and in parallel planes disposed substantially perpendicular to said axis, the grating patterns comprising each of said grating pattern pairs being spaced apart by a distance substantially equal to d2/ lambda ; where d is the grating pattern period and lambda is the effective wavelength of light from said source, said spacing thereby establishing a series of directional light transmission preferences varying cyclically in a direction transverse to said grid rulings; b. directing a beam of substantially omnidirectional light from said source through said two pairs of grating patterns along said optical axis to incidence upon photoelectric means capable of providing an electrical signal varying as a function of the intensity of light from said source incident thereupon, said photoelectric means having a field of view with respect to said light source inclusive of a plurality of cycles in said directional light transmission preference series; and c. displacing at least one of said grating patterns with respect to its pair-mate grating pattern in a direction transverse to said grid rulings, thereby effecting a variation in the intensity of the light transmitted through said two pairs of grating patterns and incident upon said photoelectric means as a function of the displacement of said at least one grating pattern.
Claim 3
Dependent Claim
14 words
a second amplitude grating pattern situated in a plane substantially perpendicular to said axis;
Claim 4
Dependent Claim
14 words
a second amplitude grating pattern situated in a plane substantially perpendicular to said axis;
Claim 5
Independent Claim
333 words
A method of determining incremental displacement between a pair of objects which comprises: a. arranging a light source and two pairs of amplitude grating patterns in sequence along an optical axis, the grid rulings comprising said grating patterns being substantially parallel and in parallel planes disposed substantially perpendicular to said axis, the grating patterns comprising each of said grating pattern pairs being spaced apart by a distance substantially equal to d2/ lambda ; where d is the grating pattern period and lambda is the effective wavelength of light from said source, said spacing thereby establishing a series of directional light transmission preferences varying cyclically in a direction transverse to said grid rulings, at least one of said grating patterns being coupled with at least one of said pair of objects in such a manner as to effect a relative movement between said at least one grating pattern and its pair-mate grating pattern in a direction transverse to said grid rulings as a function of said incremental displacement between said pair of objects; b. directing a beam of substantially omnidirectional light from said source along said optical axis and through said grating pattern pairs to incidence upon photoelectric means capable of providing an electrical signal varying as a function of the intensity of light from said source incident thereupon, said photoelectric means having a field of view with respect to said light source inclusive of a plurality of cycles in said directional light transmission preference series; c. connecting said photoelectric means as electrical signal input source in circuit with electronic means capable of indicating displacement as a function of the cycling of an electrical input signal; and d. causing said incremental displacement between said object pair and coincidentally said relative transverse movement between said pair of grating patterns; thereby effecting a cycling variation in the intensity of light transmitTed by said two pairs of grating patterns and incident upon said photoelectric means, and providing said cycling electrical input signal indicative of said incremental displacement.
Claim 6
Independent Claim
333 words
A method of determining incremental displacement between a pair of objects which comprises: a. arranging a light source and two pairs of amplitude grating patterns in sequence along an optical axis, the grid rulings comprising said grating patterns being substantially parallel and in parallel planes disposed substantially perpendicular to said axis, the grating patterns comprising each of said grating pattern pairs being spaced apart by a distance substantially equal to d2/ lambda ; where d is the grating pattern period and lambda is the effective wavelength of light from said source, said spacing thereby establishing a series of directional light transmission preferences varying cyclically in a direction transverse to said grid rulings, at least one of said grating patterns being coupled with at least one of said pair of objects in such a manner as to effect a relative movement between said at least one grating pattern and its pair-mate grating pattern in a direction transverse to said grid rulings as a function of said incremental displacement between said pair of objects; b. directing a beam of substantially omnidirectional light from said source along said optical axis and through said grating pattern pairs to incidence upon photoelectric means capable of providing an electrical signal varying as a function of the intensity of light from said source incident thereupon, said photoelectric means having a field of view with respect to said light source inclusive of a plurality of cycles in said directional light transmission preference series; c. connecting said photoelectric means as electrical signal input source in circuit with electronic means capable of indicating displacement as a function of the cycling of an electrical input signal; and d. causing said incremental displacement between said object pair and coincidentally said relative transverse movement between said pair of grating patterns; thereby effecting a cycling variation in the intensity of light transmitTed by said two pairs of grating patterns and incident upon said photoelectric means, and providing said cycling electrical input signal indicative of said incremental displacement.
Claim 7
Independent Claim
237 words
A device for providing a variation in an electrical signal as a function of physical displacement which comprises: a. a source of substantially omnidirectional light; b. photoelectric means capable of providing an electrical signal varying as a function of the intensity of light from said source incident thereupon, said photoelectric means being disposed with respect to said light source so as to receive said omnidirectional light therefrom along a path establishing an optical axis in said device; and c. at least two pairs of amplitude grating patterns disposed in sequence along said optical axis, the grid rulings comprising said grating patterns being substantially parallel and in parallel planes disposed substantially perpendicular to said axis, the grating patterns comprising each of said grating pattern pairs being spaced apart by a distance substantially equal to d2/ lambda ; where d is the grating pattern period and lambda is the effective wavelength of light from said source, said spacing thereby establishing a series of directional light transmission preferences varying cyclically in a direction transverse to said grid rulings; d. said photoelectric means having a field of view with respect to said light source inclusive of a plurality of cycles in said directional light transmission preference series; e. at least one of said pairs of grating patterns being arranged for relative movement therebetween in a direction transverse to the grid rulings of said grating patterns, thereby to effect said physical displacement.
Claim 8
Independent Claim
237 words
A device for providing a variation in an electrical signal as a function of physical displacement which comprises: a. a source of substantially omnidirectional light; b. photoelectric means capable of providing an electrical signal varying as a function of the intensity of light from said source incident thereupon, said photoelectric means being disposed with respect to said light source so as to receive said omnidirectional light therefrom along a path establishing an optical axis in said device; and c. at least two pairs of amplitude grating patterns disposed in sequence along said optical axis, the grid rulings comprising said grating patterns being substantially parallel and in parallel planes disposed substantially perpendicular to said axis, the grating patterns comprising each of said grating pattern pairs being spaced apart by a distance substantially equal to d2/ lambda ; where d is the grating pattern period and lambda is the effective wavelength of light from said source, said spacing thereby establishing a series of directional light transmission preferences varying cyclically in a direction transverse to said grid rulings; d. said photoelectric means having a field of view with respect to said light source inclusive of a plurality of cycles in said directional light transmission preference series; e. at least one of said pairs of grating patterns being arranged for relative movement therebetween in a direction transverse to the grid rulings of said grating patterns, thereby to effect said physical displacement.
Claim 9
Dependent Claim
15 words
a third amplitude grating pattern situated in a plane substantially perpendicular to said axis; and
Claim 10
Dependent Claim
15 words
a third amplitude grating pattern situated in a plane substantially perpendicular to said axis; and
Claim 11
Dependent Claim
14 words
a fourth amplitude grating pattern situated in a plane substantially perpendicular to said axis;
Claim 12
Dependent Claim
14 words
a fourth amplitude grating pattern situated in a plane substantially perpendicular to said axis;
Claim 13
Dependent Claim
50 words
A device according to claim 3 which further comprises means whereby said optical axis is folded, and wherein said two pairs of grating patterns comprise a single pair of grating patterns which, by virtue of said axis folding, is disposed at least once in each leg of said folded axis.
Claim 14
Dependent Claim
33 words
A device according to claim 3 wherein each of said grating patterns is carried by a separate transparent support and wherein one of said supports is arranged for movement in said transverse direction.
Claim 15
Dependent Claim
17 words
the grid rulings of all said grating patterns being substantially parallel as viewed along said optical axis;
Claim 16
Dependent Claim
17 words
the grid rulings of all said grating patterns being substantially parallel as viewed along said optical axis;
Claim 17
Dependent Claim
150 words
said first and second grating patterns, and said third and fourth grating patterns, respectively, being spaced apart by a distance substantially equal to d2/ lambda ; where d is the grating pattern period and lambda is the effective wavelength of light from said source, said spacing thereby establishing a series of directional light transmission preferences varying cyclically in a direction transverse to said grid rulings; d. said photoelectric means having a field of view with respect to said light source inclusive of a plurality of cycles in said directional light transmission preference series; e. at least one of said grating patterns being arranged for movement in its plane in a direction transverse to its grid rulings, thereby to effect the displacement to be indicated; and f. electronic means in circuit with said photoelectric means and responsive to electrical signals provided by said photoelectric means to provide an indication of displacement.
Claim 18
Dependent Claim
150 words
said first and second grating patterns, and said third and fourth grating patterns, respectively, being spaced apart by a distance substantially equal to d2/ lambda ; where d is the grating pattern period and lambda is the effective wavelength of light from said source, said spacing thereby establishing a series of directional light transmission preferences varying cyclically in a direction transverse to said grid rulings; d. said photoelectric means having a field of view with respect to said light source inclusive of a plurality of cycles in said directional light transmission preference series; e. at least one of said grating patterns being arranged for movement in its plane in a direction transverse to its grid rulings, thereby to effect the displacement to be indicated; and f. electronic means in circuit with said photoelectric means and responsive to electrical signals provided by said photoelectric means to provide an indication of displacement.
Claim 19
Dependent Claim
95 words
A device according to claim 3 wherein said two pairs of grating patterns respectively comprise, in sequence along said optical axis, first and second grating patterns carried on separate transparent supports, and third and fourth grating patterns carried on separate transparent supports, and wherein said supports are arranged for coincident relative transverse movement in such a manner that the direction of relative movement of said first grating pattern with respect to said second grating pattern is opposite to the direction of relative movement of said third grating pattern with respect to said fourth grating pattern.
Claim 20
Dependent Claim
44 words
A device according to claim 6 wherein said first grating pattern is carried on a first support, said second and third grating patterns are carried, respectively, on opposite faces of a second support, and said fourth grating pattern is carried on a third support.
Claim 21
Dependent Claim
69 words
A device according to claim 6 which further comprises reflective means whereby said optical axis is folded, and wherein, by virtue of said axis folding, a grating pattern carried by one of a pair of said supports comprises both of said first and fourth grating patterns and a grating pattern carried by the other one of said pair of supports comprises both of said second and third grating patterns.
Claim 22
Dependent Claim
82 words
A device according to claim 6 wherein said first and fourth grating patterns are carried by a first transparent support and a separate grating pattern is carried by a second transparent support, said device further comprising means whereby said optical axis is folded and caused to double-pass said second support, said separate grating pattern thereby comprising said second and third grating patterns, at least one of said first and second supports beIng arranged to provide relative opposite transverse movement between said supports.
Claim 23
Dependent Claim
77 words
A displacement-indicating device comprising: a. a source of substantially omnidirectional light; b. photoelectric means capable of providing an electrical signal varying as a function of the intensity of light from said source incident thereupon, said photoelectric means being disposed with respect to said light source so as to receive said omnidirectional light therefrom along a path establishing an optical axis in said device; c. a plurality of amplitude grating patterns comprising, in sequence along said optical axis:
Claim 24
Dependent Claim
77 words
A displacement-indicating device comprising: a. a source of substantially omnidirectional light; b. photoelectric means capable of providing an electrical signal varying as a function of the intensity of light from said source incident thereupon, said photoelectric means being disposed with respect to said light source so as to receive said omnidirectional light therefrom along a path establishing an optical axis in said device; c. a plurality of amplitude grating patterns comprising, in sequence along said optical axis:
Claim 25
Dependent Claim
82 words
A device according to claim 10 wherein said first and fourth grating patterns are carried by a first transparent support and a separate grating pattern is carried by a second transparent support, said device further comprising means whereby said optical axis is folded and caused to double-pass said second support, said separate grating pattern thereby comprising said second and third grating patterns, at least one of said first and second supports being arranged to provide relative opposite transverse movement between said supports.
Claim 26
Dependent Claim
60 words
A device according to claim 10 wherein a plurality of said grating patterns are arranged for coincident transverse movement in such a manner as to effect relative movement of said first grating pattern with respect to said second grating pattern in a direction opposite to the relative movement of said third grating pattern with respect to said fourth grating pattern.
Claim 27
Dependent Claim
44 words
A device according to claim 12 wherein said second and said third grating patterns are carried in common by a single transparent support, and wherein said support is arranged for said transverse movement, thereby to effect said opposite directions of relative grating pattern movement.
Claim 28
Dependent Claim
87 words
A device according to claim 10 wherein said first grating pattern is carried by a first transparent support and said second grating pattern is carried by a second transparent support, and wherein said means establishing said optical axis comprises means whereby said optical axis is folded and caused to double-pass said supports, said second and first grating patterns thereby comprising, respectively, said third and fourth grating patterns, at least one of said first and second supports being arranged to provide relative opposite transverse movement between said supports.
Claim 29
Dependent Claim
37 words
A device according to claim 14 wherein said optical axis folding means comprises a reflective surface situated subsequent to said second grating pattern in said sequence along said optical axis and disposed substantially perpendicular to said axis.
Claim 30
Dependent Claim
125 words
A device according to claim 10 wherein: a. at least one of said grating patterns comprises a plurality of regions wherein the grid rulings comprising each of said grating pattern regions are transversely displaced with respect to the grid rulings comprising each other grating pattern of said plurality of regions by a fractional increment of the period of said at least one grating pattern; and b. said photoelectric means comprises a plurality of photocells, each of said photocells being arranged to respectively receive light transmitted by a different one of said plurality of grating pattern regions; whereby a plurality of phase-displaced electrical signals are generated by said photoelectric means in response to light transmitted through said plurality of amplitude grating patterns along said optical axis.
Claim 31
Dependent Claim
49 words
A device according to claim 16 wherein said at least one grating pattern comprises four grating pattern regions, and wherein said regions are displaced sequentially by an increment substantially equal to one-quarter of said grating pattern period, thereby providing phase-quadrature displacement in four signals generated by said photoelectric means.
References Cited (Backward Citations)
US2993279A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-10-29 | 1977-04-30 | 1977-10-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-29 | 1981-04-30 | 1981-10-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-29 | 1985-04-30 | 1985-10-30 | $7700.00 | Window Closed / Lapsed |