US3619022A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of making an object dependent diffuser
Assignee: International Business Machines Corp
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Filing: 1970-09-17
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Granted: 1971-11-09
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Expires: 1990-09-17
Abstract
Abstract A technique for making optimized phase objects which can uniformly diffuse the information content in a physical wave front across a defined recording plane.
Inventors
- 👤 Peter M Hirsch
- 👤 James A Jordan Jr
- 👤 Louis B Lesem
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 01:01
CPC Classifications
G; G03; G03H; G03H1/00; G03H1/04; G03H1/08; Y; Y10; Y10S; Y10S359/00; Y10S359/90
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
253 words
The method of constructing a diffuser which will provide an object dependent wave front of nearly constant amplitude at an arbitrary plane comprising the steps of: A. calculating by machine the phase distribution from said object by: 1. specifying the amplitude of each object point and assigning a random phase factor according to a uniform set of random numbers to each such point, 2. calculating the form at said arbitrary plane of the wave front which would propagate from an object having said specified amplitude and phase, and 3. setting all the amplitude factors in said calculated arbitrary plane wave front to a uniform value so as to produce a normalized wave front having only phase information; B. back propagating said normalized wave front to produce a new wave front at the location of said object, C. comparing the amplitude distribution of said new wave front with the amplitude distribution of said object points calculated in step (A)2. D. calculating the form at said arbitrary plane of the wave front which would propagate from an object having the amplitude distribution of step (A)1 and the phase distribution from the said new wave front of step (B). E. repeating steps D, A(3), (B) and (C) until the mean deviation between the amplitude distribution of said new wave front at said object location and the amplitude distribution of said specified object falls within acceptable levels, and constructing said diffuser having controlled phase retarding areas in accordance with the phase distribution of said normalized wave front.
Claim 2
Independent Claim
253 words
The method of constructing a diffuser which will provide an object dependent wave front of nearly constant amplitude at an arbitrary plane comprising the steps of: A. calculating by machine the phase distribution from said object by: 1. specifying the amplitude of each object point and assigning a random phase factor according to a uniform set of random numbers to each such point, 2. calculating the form at said arbitrary plane of the wave front which would propagate from an object having said specified amplitude and phase, and 3. setting all the amplitude factors in said calculated arbitrary plane wave front to a uniform value so as to produce a normalized wave front having only phase information; B. back propagating said normalized wave front to produce a new wave front at the location of said object, C. comparing the amplitude distribution of said new wave front with the amplitude distribution of said object points calculated in step (A)2. D. calculating the form at said arbitrary plane of the wave front which would propagate from an object having the amplitude distribution of step (A)1 and the phase distribution from the said new wave front of step (B). E. repeating steps D, A(3), (B) and (C) until the mean deviation between the amplitude distribution of said new wave front at said object location and the amplitude distribution of said specified object falls within acceptable levels, and constructing said diffuser having controlled phase retarding areas in accordance with the phase distribution of said normalized wave front.
Claim 3
Dependent Claim
24 words
calculating the form at said arbitrary plane of the wave front which would propagate from an object having said specified amplitude and phase, and
Claim 4
Dependent Claim
24 words
calculating the form at said arbitrary plane of the wave front which would propagate from an object having said specified amplitude and phase, and
Claim 5
Dependent Claim
23 words
The method of claim 1 wHerein said step of back propagating is accomplished by calculating the inverse transform of said normalized wave front.
Claim 6
Dependent Claim
19 words
The method of claim 2 wherein said mean deviation of said amplitudes is defined in the least squares sense.
Claim 7
Dependent Claim
164 words
setting all the amplitude factors in said calculated arbitrary plane wave front to a uniform value so as to produce a normalized wave front having only phase information; B. back propagating said normalized wave front to produce a new wave front at the location of said object, C. comparing the amplitude distribution of said new wave front with the amplitude distribution of said object points calculated in step (A)2. D. calculating the form at said arbitrary plane of the wave front which would propagate from an object having the amplitude distribution of step (A)1 and the phase distribution from the said new wave front of step (B). E. repeating steps D, A(3), (B) and (C) until the mean deviation between the amplitude distribution of said new wave front at said object location and the amplitude distribution of said specified object falls within acceptable levels, and constructing said diffuser having controlled phase retarding areas in accordance with the phase distribution of said normalized wave front.
Claim 8
Dependent Claim
164 words
setting all the amplitude factors in said calculated arbitrary plane wave front to a uniform value so as to produce a normalized wave front having only phase information; B. back propagating said normalized wave front to produce a new wave front at the location of said object, C. comparing the amplitude distribution of said new wave front with the amplitude distribution of said object points calculated in step (A)2. D. calculating the form at said arbitrary plane of the wave front which would propagate from an object having the amplitude distribution of step (A)1 and the phase distribution from the said new wave front of step (B). E. repeating steps D, A(3), (B) and (C) until the mean deviation between the amplitude distribution of said new wave front at said object location and the amplitude distribution of said specified object falls within acceptable levels, and constructing said diffuser having controlled phase retarding areas in accordance with the phase distribution of said normalized wave front.
Claim 9
Dependent Claim
18 words
The method of claim 3 wherein said image points are places so as to define a continuous function.
Claim 10
Dependent Claim
33 words
The method of claim 4 wherein said object is constructed by plotting said required phase as amplitude on a multigrey level plotter, photoreducing said plot onto a film and etching the resultant film.
Claim 11
Independent Claim
189 words
A method of diffusing a wave front from an object across an arbitrary plane, comprising the steps of: constructing a diffuser having selective phase-retarding areas in accordance with required phase distribution calculations based on the wave front from said object, said required phase distribution calculated in a machine by: calculating the wave front at said arbitrary plane using the amplitude factors in said wave front from said object and phase distribution selected from a uniform set of random numbers, setting all the amplitude factors in said calculated arbitrary plane wave front to a uniform value so as to produce a normalized wave front having only phase information, back propagating said normalized wave front to provide a new wave front at the location of said object; using the original object amplitude factors and the phase distribution of said new wave front to provide a new object wave front, and; repeating the above steps until the mean deviation between the said original object amplitude factors and the amplitude distribution of said new wave front fall within acceptable levels, the phase distribution in said new wave front being said required phase distribution.
Claim 12
Independent Claim
189 words
A method of diffusing a wave front from an object across an arbitrary plane, comprising the steps of: constructing a diffuser having selective phase-retarding areas in accordance with required phase distribution calculations based on the wave front from said object, said required phase distribution calculated in a machine by: calculating the wave front at said arbitrary plane using the amplitude factors in said wave front from said object and phase distribution selected from a uniform set of random numbers, setting all the amplitude factors in said calculated arbitrary plane wave front to a uniform value so as to produce a normalized wave front having only phase information, back propagating said normalized wave front to provide a new wave front at the location of said object; using the original object amplitude factors and the phase distribution of said new wave front to provide a new object wave front, and; repeating the above steps until the mean deviation between the said original object amplitude factors and the amplitude distribution of said new wave front fall within acceptable levels, the phase distribution in said new wave front being said required phase distribution.
Claim 13
Dependent Claim
23 words
The method of claim 6 wherein said step of back propagating is accomplished by calculating the inverse transform of said normalized wave front.
Claim 14
Dependent Claim
19 words
The method of claim 7 wherein said mean deviation of said amplitudes is defined in the least squares sense.
References Cited (Backward Citations)
US3539241A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-11-08 | 1975-05-10 | 1975-11-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-08 | 1979-05-10 | 1979-11-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-08 | 1983-05-10 | 1983-11-09 | $7700.00 | Window Closed / Lapsed |