US3780217A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heterodyne imaging device for providing high resolution images
Assignee: Bendix Corp
•
Filing: 1972-05-11
•
Granted: 1973-12-18
•
Expires: 1992-05-11
Abstract
Abstract Several heterodyne microscopes are illustrated herein in which light from a point source is directed to interfere with light scattered from an object to provide a large area interference pattern representing a point on that object. Scanning apparatus varies the interference pattern to represent different object points. Conventional heterodyne signal processing apparatus processes light from the interference pattern to provide an image. The resolution of the image is determined by the size of the point source and by the percentage of the area of the interference pattern from which the processing apparatus receives signals. A high resolution image is obtained by using a small pinhole aperture to provide the point source and by using a diffusive surface to receive and scatter light from the interference pattern to the signal processing apparatus.
Inventors
- 👤 T Sawatari
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 21:28
CPC Classifications
G; G02; G02F; G02F2/00; G02F2/002; G03; G03H; G03H1/00; G03H1/04; G03H1/08
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
180 words
A heterodyne device for providing a high resolution image of an object comprising: means for providing a wavefront having an amplitude representative of a point on the object; means for varying said wavefront to sequentially provide amplitude representations of different points on said object; means for providing a signal identifying the locations of the represented object points; a diffusive surface for receiving and scattering at least a substantial portion of said wavefront; and signal processing means for using said signal and wave energy scattered from said diffusive surface to form an image of said object, the resolution of said image being determined at least in part by the percentage of the cross-sectional area of said wavefront from which said imaging means receives wave energy, said diffusive surface directing at least a portion of the wave energy striking each position on said surface to said processing means and thereby causing the resolution of said image to be at least partially dependent on the area of said diffusive surface and to be independent of the signal receiving area of said processing means.
Claim 2
Dependent Claim
180 words
A heterodyne device for providing a high resolution image of an object comprising: means for providing a wavefront having an amplitude representative of a point on the object; means for varying said wavefront to sequentially provide amplitude representations of different points on said object; means for providing a signal identifying the locations of the represented object points; a diffusive surface for receiving and scattering at least a substantial portion of said wavefront; and signal processing means for using said signal and wave energy scattered from said diffusive surface to form an image of said object, the resolution of said image being determined at least in part by the percentage of the cross-sectional area of said wavefront from which said imaging means receives wave energy, said diffusive surface directing at least a portion of the wave energy striking each position on said surface to said processing means and thereby causing the resolution of said image to be at least partially dependent on the area of said diffusive surface and to be independent of the signal receiving area of said processing means.
Claim 3
Dependent Claim
122 words
The heterodyne device of claim 1 wherein saId wavefront comprises an interference pattern, and said means for providing said wavefront includes: means for directing a first wave energy signal to strike and be scattered and modulated to thereby provide a modulated wave energy signal having a large cross-sectional area and representing said object; a hologram of a pinhole aperture disposed to receive by the object said modulated wave energy from said object; and means for directing a reference beam of wave energy having a frequency slightly different from the frequency of said modulated wave energy to also strike said hologram, said hologram modulating received wave energy and providing a temporally varying interference pattern having an amplitude representing a point on said object.
Claim 4
Dependent Claim
50 words
The heterodyne device of claim 2 in which said varying means comprise means for varying the convergence of said reference beam and for varying the angle at which said reference beam strikes said hologram to thereby change the location of the point on said object represented by said interference pattern.
Claim 5
Dependent Claim
110 words
The heterodyne device of claim 1 wherein said wavefront comprises an interference pattern, and said means for providing said wavefront include: means for directing a first wave energy signal to strike and be modulated and scattered by the object to thereby provide a modulated wave energy signal having a large cross-sectional area and representing said object; and means for providing a second wave energy signal representing a point source of wave energy and for directing said second signal to interfere with said modulated signal, said second signal having a frequency slightly different from the frequency of said modulated signal and thereby providing a temporally varying interference pattern comprising said wavefront.
Claim 6
Dependent Claim
165 words
The heterodyne device of claim 4 in which the resolution of the image is at least partially determined by the sensitivity of the device to variations between signals representing different points on the object, and the device includes apparatus for increasing the resolution of the image comprising: means for providing a second temporally varying interference pattern representing the same object point represented by said interference pattern; a second diffusive surface for receiving at least a substantial portion of said second interference pattern and for scattering wave energy from said second pattern to said signal processing means; and means for utilizing wave energy scattered from said diffusive surface and wave energy scattered from said second diffusive surface to provide a summation signal, the variation of said interference patterns to represent different object points providing said summation signal with larger amplitude variations that are more easily detected and processed by said signal processing means than the amplitude variations of anY of the components of said summation signal.
Claim 7
Dependent Claim
73 words
The heterodyne device of claim 4 in which: said means for directing said second wave energy signal comprise reflective means for directing said second signal to interfere with wave energy modulated and scattered by the object; and said diffusive surface for receiving and scattering at least a substantial portion of said interference wavefront comprises a reflective diffusive surface, said heterodyne device thereby comprising an all-reflective device permitting image formation utilizing ultraviolet laser light.
Claim 8
Dependent Claim
39 words
The heterodyne device of claim 6 in which said reflective means for directing said second signal to interfere with wave energy modulated by said object comprise a reflective hologram representing a point source of wave energy proximate the object.
Claim 9
Dependent Claim
99 words
The heterodyne device of claim 4 in which said means for providing and directing said second wave energy signal include: means defining a pinhole aperture for receiving wave energy and causing said received wave energy to propagate in a diverging distribution, said diverging distribution comprisinG said second signal; and a beam splitter for receiving and superposing said modulated signal and said second signal to provide said interference pattern, said beam splitter being positioned to project an image of said aperture onto a point on said object, said interference pattern representing the point on said object receiving said projected image.
Claim 10
Dependent Claim
51 words
The heterodyne device of claim 8 wherein said varying means comprise means for providing a relative movement between said object and said pinhole aperture to scan said projected image of said aperture across said object and thereby vary the amplitude of said interference pattern to represent different points on the object.
Claim 11
Dependent Claim
77 words
The heterodyne device of claim 8 in which: said means for providing and directing said second wave energy signal include means for directing a beam of wave energy having a frequency slightly different from the frequency of said modulated signal along a straight line path toward said object; and said pinhole aperture and said beam splitter are disposed along said path with said beam splitter disposed between said object and said aperture to provide a compact structure.
References Cited (Backward Citations)
US3644665A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-12-17 | 1977-06-18 | 1977-12-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-17 | 1981-06-18 | 1981-12-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-17 | 1985-06-18 | 1985-12-18 | $7700.00 | Window Closed / Lapsed |