US3751132A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical apparatus for symbol regonition comprising a plurality of channels
Assignee: US Philips Corp
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Filing: 1971-01-28
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Granted: 1973-08-07
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Expires: 1991-01-28
Abstract
Abstract The invention relates to an optical apparatus for symbol recognition comprising a plurality of channels which include holographic filters. The Fourier spectrum of the symbol to be examined is produced in the plane of the various spatially separate filters by forming an image of a matrix of illuminated diaphragms in the filter plane, the individual diaphragms being illuminated, for example, mutually incoherently. The individual diaphragms of the matrix may be sequentially illuminated by means of an electronically controlled light deflector, for example a digital light deflector.
Inventors
- 👤 G Croh
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 11:15
CPC Classifications
G; G02; G02B; G02B5/00; G02B5/32; G06; G06V; G06V10/00; G06V10/88; G06V10/89; G06V10/893; G06V10/895
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
88 words
A multi-channel optical symbol recognition apparatus, comprising a planar array of holographic filters each corresponding to a recognition channel, a planar matrix of diaphragms, each diaphragm of the matrix corresponding to one of the holographic filters, the symbol to be recognized being placed between the matrix and the filters, optical means for forming an image of each diaphragm on the corresponding holographic filter, and means for projecting coherent radiation through each diaphragm that is incoherent with respect to the radiation projected through the other diaphragms of the matrix.
Claim 2
Dependent Claim
88 words
A multi-channel optical symbol recognition apparatus, comprising a planar array of holographic filters each corresponding to a recognition channel, a planar matrix of diaphragms, each diaphragm of the matrix corresponding to one of the holographic filters, the symbol to be recognized being placed between the matrix and the filters, optical means for forming an image of each diaphragm on the corresponding holographic filter, and means for projecting coherent radiation through each diaphragm that is incoherent with respect to the radiation projected through the other diaphragms of the matrix.
Claim 3
Dependent Claim
37 words
An optical apparatus as claimed in claim 1, characterized in that there is inserted in the radiation path at a point preceding the diaphragm matrix an electronically controllable light deflector capable of successively illuminating the individual diaphragms.
Claim 4
Dependent Claim
45 words
An optical apparatus as claimed in claim 2, characterized in that there are inserted in the radiation path at points succeeding the light deflector a field lens and a fly''s eye lens for focussing the beam emanating from the light deflector on the diaphragm matrix.
Claim 5
Dependent Claim
28 words
An optical apparatus as claimed in claim 1, characterized in that all the spatially separate holographic filters have been recorded with the use of the same reference source.
Claim 6
Dependent Claim
33 words
An optical apparatus as claimed in claim 1, characterized in that identical filters are arranged in several of the separate transmission channels, the output signals of the filters being superimposed on one another.
Claim 7
Dependent Claim
105 words
An optical apparatus as claimed in claim 1, characterized in that in the radiation path at a point preceding the diaphragm matrix a field lens and a fly''s eye lens in this order are arranged for simultaneously illuminating the individual diaphragms and that there is arranged between the field lens and the fly''s eye lens a phase shifting means comprising a matrix of optical modulators, each modulator corresponding to one diaphragm for modulating the phase of the light so that in space it is constant but in time it exhibits statistic fluctuations with respect to the phases of the light emanating from the remaining diaphragms.
References Cited (Backward Citations)
US3600054A
Cited
US3530442A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-08-06 | 1977-02-05 | 1977-08-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-08-06 | 1981-02-05 | 1981-08-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-08-06 | 1985-02-05 | 1985-08-07 | $7700.00 | Window Closed / Lapsed |