Patent US3682526A successfully refreshed from Google Patents.
US3682526A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Holography with blocked unmodulated object beam light
Assignee: Canon Inc
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Filing: 1970-08-19
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Granted: 1972-08-08
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Expires: 1990-08-19
Abstract
Abstract In the method and apparatus disclosed, a laser, a beam splitter, and one polarizer form two beams one of which is linearly polarized. The polarized beam is directed onto an object to be recorded so that the object depolarizes the light striking it, the depolarized light is sensed with a holographic sensing material through a second linear polarizer whose direction of polarization is transverse to that of the polarized beam. Thus effectively the second polarizer allows only light that has struck the object to reach the material. The second beam is directed to the other side of the sensing material. A mirror deflects part of the polarized light that does not strike the object back onto the shaded portions of the object. This reflected light is also depolarized by the object and sensed through the second polarizer.
Inventors
- 👤 Kazuya Matsumoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 18:57
CPC Classifications
G; G03; G03H; G03H1/00; G03H1/02; G03H1/024; G03H1/0248; G03H2222/00; G03H2222/31
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
163 words
The method of making A holographic record of a subject, which comprises forming a first beam of light and a second beam of light, directing the first beam of light at a recording medium, directing the second beam at a subject so that light may be reflected from the subject toward the medium, locating the medium relative to the subject and directing the second beam so that at least a portion of the light from the second beam bypasses the subject and is directed at the medium, reflecting at least a portion of the light of the second beam directed at the medium toward the subject, and limiting the intensity of the portion of the second beam which bypasses the subject and is directed at the medium by polarizing the second beam before it strikes the subject and subjecting the light between the subject and the medium to polarization that limits the intensity of the portion of the second beam that is polarized.
Claim 2
Independent Claim
163 words
The method of making A holographic record of a subject, which comprises forming a first beam of light and a second beam of light, directing the first beam of light at a recording medium, directing the second beam at a subject so that light may be reflected from the subject toward the medium, locating the medium relative to the subject and directing the second beam so that at least a portion of the light from the second beam bypasses the subject and is directed at the medium, reflecting at least a portion of the light of the second beam directed at the medium toward the subject, and limiting the intensity of the portion of the second beam which bypasses the subject and is directed at the medium by polarizing the second beam before it strikes the subject and subjecting the light between the subject and the medium to polarization that limits the intensity of the portion of the second beam that is polarized.
Claim 3
Dependent Claim
59 words
The method as in claim 1, wherein the step of limiting includes substantially blocking the effect of the portions of the second beam which bypass the subject upon the medium by subjecting the light between the subject and the medium to polarization that substantially cancels the portion of the second beam directed at the medium in bypassing the subject.
Claim 4
Dependent Claim
54 words
The method as in claim 2, wherein the step of polarizing the second beam before it strikes the subject includes linearly polarizing the second beam in one direction, and wherein the step of subjecting the light to polarization includes linearly polarizing the light transverse to the one direction between the subject and the medium.
Claim 5
Dependent Claim
43 words
The method as in claim 2, wherein the first beam is directed toward one face of the recording medium and the second beam is directed toward the opposite face of the recording medium, said recording medium being substantially flat and having two faces.
Claim 6
Dependent Claim
43 words
The method as in claim 3, wherein the first beam is directed toward one face of the recording medium and the second beam is directed toward the opposite face of the recording medium, said recording medium being substantially flat and having two faces.
Claim 7
Dependent Claim
22 words
The method as in claim 5, wherein the step of reflecting includes locating a transparent mirror between the subject and the medium.
Claim 8
Dependent Claim
39 words
The method as in claim 6, wherein the step of forming the second beam and the first beam includes the step of generating a single source beam from a source and forming the two beams with a beam splitter.
Claim 9
Dependent Claim
26 words
The method as in claim 7, wherein the step of forming the source beam includes forming the source beam as a coherent beam with a laser.
Claim 10
Dependent Claim
40 words
The method as in claim 8, wherein the first beam is adjusted sufficiently to include light polarized in a manner comparable to the polarization effected by the step of subjecting the light between the subject and the medium to polarization.
Claim 11
Independent Claim
204 words
An apparatus for holographic recording of a subject, comprising beam forming means for forming a first beam of light and a second beam of light, holographic recording means for forming a holographic recording, first beam directing means for directing the first beam toward the holographic recording means, second beam directing means for directing the second beam so that a portion of the light of the second beam strikes the subject and a second portion of the light from the second beam bypasses the subject and is directed toward the medium; protector means for substantially limiting the intensity of the second portion of the second beam that bypasses the subject and is directed at said recording means; said protector means including polarizing means positioned in the path of the second beam before the subject for polarizing the second beam before it reaches the subject, and second polarizing means positioned between the subject and the recording means for polarizing the light from the subject in such a manner that the portion of the beam which bypasses the subject is reduced in intensity; and reflecting means for reflecting a part of the second portion of the second beam which is Directed at the medium, onto the subject.
Claim 12
Independent Claim
204 words
An apparatus for holographic recording of a subject, comprising beam forming means for forming a first beam of light and a second beam of light, holographic recording means for forming a holographic recording, first beam directing means for directing the first beam toward the holographic recording means, second beam directing means for directing the second beam so that a portion of the light of the second beam strikes the subject and a second portion of the light from the second beam bypasses the subject and is directed toward the medium; protector means for substantially limiting the intensity of the second portion of the second beam that bypasses the subject and is directed at said recording means; said protector means including polarizing means positioned in the path of the second beam before the subject for polarizing the second beam before it reaches the subject, and second polarizing means positioned between the subject and the recording means for polarizing the light from the subject in such a manner that the portion of the beam which bypasses the subject is reduced in intensity; and reflecting means for reflecting a part of the second portion of the second beam which is Directed at the medium, onto the subject.
Claim 13
Dependent Claim
45 words
An apparatus as in claim 10, wherein said recording means is flat and has two faces, and wherein light from the subject is directed at one face of said recording means and said first beam is directed at the other face of said recording means.
Claim 14
Dependent Claim
41 words
An apparatus as in claim 10, wherein said reflecting means includes transparent mirror means located between the subject and said recording means for reflecting light from the second portion of the second beam toward the subject and thereby illuminating the subject.
Claim 15
Dependent Claim
21 words
An apparatus as in claim 12, wherein said second polarizing means is located between said mirror means and said recording means.
Claim 16
Dependent Claim
34 words
An apparatus as in claim 13, wherein said first polarizing means linearly polarizes said second beam in one direction and said second polarizing means linearly polarizes said second beam in a direction transverse thereto.
Claim 17
Dependent Claim
31 words
An apparatus as in claim 14, wherein said beam forming means includes laser means for forming a source beam of coherent light, and beam splitter means for forming the two beams.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-08-08 | 1976-02-07 | 1976-08-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-08 | 1980-02-07 | 1980-08-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-08 | 1984-02-07 | 1984-08-08 | $7700.00 | Window Closed / Lapsed |