US3744910A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for optical investigations and measurements with the aid of several coherent light beams
Assignee: Nederlandse Organisatie voor Toegepast Natuurwetenschappelijk Onderzoek TNO
•
Filing: 1971-06-11
•
Granted: 1973-07-10
•
Expires: 1991-06-11
Abstract
Abstract In an apparatus for optical investigations and measurements in which a laser and a beam splitter produce coherent beams of monochromatic light, the beam splitter is a hologram that is a photographic reproduction of the intersection of corresponding coherent beams of monochromatic light. The superposition of a plurality of such holograms in different positions results in a multiple beam splitter that provides a plurality of coherent beams. These beams are used for the three-dimensional determination of the speed of a moving effluvium and for the elimination of noise in the output signals.
Inventors
- 👤 Deelen W Van
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 12:14
CPC Classifications
G; G01; G01P; G01P13/00; G01P13/02; G01P5/00; G01P5/26; G02; G02B; G02B5/00; G02B5/32
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
190 words
An apparatus for the optical determination of the velocity of an effluvium with light-scattering properties or components comprising a first light Source producing a monochromatic light beam, a beam splitter splitting said monochromatic light beam into a first two or more divergent light beams, means to cause said divergent light beams to converge at a point of convergence, transparent means to conduct a moving effluvium with lightscattering properties or components past said point of convergence, and means in the axis of at least one of said light beams beyond said point of convergence to detect interference frequencies in light received from said point of convergence, said beam splitter being a multiple hologram of a planar superposition in different positions of at least two holograms on one photographic film, each hologram being a reproduction of the point of intersection of a second two or more coherent light beams produced by a second light source similar to the said first light source, said planar superposition in different positions of said at least two holograms being positions relatively rotated around the axis of one of said second two or more coherent light beams.
Claim 2
Independent Claim
190 words
An apparatus for the optical determination of the velocity of an effluvium with light-scattering properties or components comprising a first light Source producing a monochromatic light beam, a beam splitter splitting said monochromatic light beam into a first two or more divergent light beams, means to cause said divergent light beams to converge at a point of convergence, transparent means to conduct a moving effluvium with lightscattering properties or components past said point of convergence, and means in the axis of at least one of said light beams beyond said point of convergence to detect interference frequencies in light received from said point of convergence, said beam splitter being a multiple hologram of a planar superposition in different positions of at least two holograms on one photographic film, each hologram being a reproduction of the point of intersection of a second two or more coherent light beams produced by a second light source similar to the said first light source, said planar superposition in different positions of said at least two holograms being positions relatively rotated around the axis of one of said second two or more coherent light beams.
Claim 3
Dependent Claim
109 words
An apparatus according to claim 1 wherein said multiple holographic beam splitter is adapted to produce a transmitted light beam and at least one pair of diffracted light beams which are substantially symmetrical with relation to said transmitted light beam and wherein said means to detect interference frequencies is arranged in one of said pair of diffracted light beams beyond said point of convergence and a second means to detect interferences frequencies is arranged in the axis of the other of said pair of diffracted light beams before said point of convergence and the outputs of said means to detect are led to the inputs of a differential amplifier.
Claim 4
Dependent Claim
42 words
An apparatus according to claim 1, wherein multiple holographic beam splitter comprises a plurality of multiple holograms mounted in a circular fashion and rotatable about its center, which on revolution causes a frequency shift in the frequency of a diffracted light beam.
Claim 5
Dependent Claim
54 words
An apparatus according to claim 1, designed to determine at least three spatial components of the velocity of the effluvium, wherein the hologram is at least threefold and interference detectors are present in the axes of at least three light beams that intersect the optical axis of the apparatus in the point of measurement.
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) | 1976-07-09 | 1977-01-08 | 1977-07-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-09 | 1981-01-08 | 1981-07-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-09 | 1985-01-08 | 1985-07-10 | $7700.00 | Window Closed / Lapsed |