US4090792A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Single beam photometer for investigating a specimen
Assignee: Bayer AG
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Filing: 1976-06-22
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Granted: 1978-05-23
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Expires: 1996-06-22
Abstract
Abstract In a single beam photometer the transmitted radiation is modulated in respect of wavelength. As the modulator, an interference pattern filter is used, whose transmitted wavelength agrees in the middle approximately with the absorption band to be measured. The interference pattern filter is either arranged so as to be rotatable in the beam path or oscillates at right angles to the optical axis. The electronic system is tuned to the first harmonic of the interference pattern filter frequency; i.e. the effects of signals of other frequencies are suppressed by the electronics.
Inventors
- 👤 Konrad Bunge
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 21:48
CPC Classifications
G; G01; G01J; G01J3/00; G01J3/28; G01J3/42; G01J3/433
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
189 words
A single beam photometer for investigating a specimen, comprising: a. source means for projecting a beam of light in a predetermined path in the form of a closely limited cone; b. a graded interference filter having an optical axis and a range of wavelength transmission substantially coinciding with the absorption wavelength of the specimen to be investigated, means mounting the filter for positioning same in the path of said beam of light at the closely limited cone; c. moving means connected to the mounting means of said interference filter for periodically moving said filter relative to said beam of light at a basic frequency to modulate said beam of light; d. cell means for holding a specimen to be investigated disposed in the path of said modulated light beam; e. receiving means receptive of the beam of light passing through the specimen for converting said beam into information signals representative of a single harmonic of the basic frequency of movement of said filter; and f. means tuned to the single harmonic of the basic frequency for evaluating the information to obtain values of a desired characteristic of the specimen.
Claim 2
Dependent Claim
189 words
A single beam photometer for investigating a specimen, comprising: a. source means for projecting a beam of light in a predetermined path in the form of a closely limited cone; b. a graded interference filter having an optical axis and a range of wavelength transmission substantially coinciding with the absorption wavelength of the specimen to be investigated, means mounting the filter for positioning same in the path of said beam of light at the closely limited cone; c. moving means connected to the mounting means of said interference filter for periodically moving said filter relative to said beam of light at a basic frequency to modulate said beam of light; d. cell means for holding a specimen to be investigated disposed in the path of said modulated light beam; e. receiving means receptive of the beam of light passing through the specimen for converting said beam into information signals representative of a single harmonic of the basic frequency of movement of said filter; and f. means tuned to the single harmonic of the basic frequency for evaluating the information to obtain values of a desired characteristic of the specimen.
Claim 3
Dependent Claim
36 words
A single beam photometer as in claim 1, wherein the mounting means disposes the optical axis of said intereference filter displaced from the light beam, and said moving means comprises means for rotating said intereference filter.
Claim 4
Dependent Claim
42 words
A single beam photometer as in claim 2, wherein the mounting means comprises adjusting means for selectively displacing said interference filter in the vertical direction to adjust the spacing between the optical axis and said beam of light to a preselected distance.
Claim 5
Dependent Claim
32 words
A single beam photometer as in claim 1, wherein the moving means comprises shift means for shifting said interference filter in the direction of changing wavelength relative to said beam of light.
Claim 6
Dependent Claim
31 words
A single beam photometer as in claim 1, in which said moving means comprises oscillating means for periodically shifting said interference filter back and forth in the direction of changing wavelength.
Claim 7
Dependent Claim
36 words
A single beam photometer as in claim 1, wherein said moving further comprises tilt means for selectively tilting said interference filter through a preselected angle about an axis perpendicular to the optical axis of said filter.
Claim 8
Dependent Claim
25 words
A single beam photometer as in claim 6, in which said tilt means comprises means for periodically tilting said interference filter at a selected frequency.
Claim 9
Dependent Claim
28 words
A single beam photometer as in claim 7, in which the selected frequency of said tilt means is substantially less than the basic frequency of said moving means.
Claim 10
Dependent Claim
23 words
A single beam photometer as in claim 1, in which the evaluating means comprises a filter tunable to harmonics of said basic frequency.
Claim 11
Dependent Claim
29 words
A single beam photometer as in claim 9, in which said evaluating means further includes an amplifier lockable to the harmonics of the basic frequency of said interference filter.
Claim 12
Dependent Claim
27 words
A single beam photometer as in claim 1, and further comprising chopping means disposed between said light source and said interference filter for chopping said light beam.
References Cited (Backward Citations)
US3744918A
Cited
US3994592A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-05-22 | 1981-11-21 | 1982-05-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-05-22 | 1985-11-21 | 1986-05-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-05-22 | 1989-11-21 | 1990-05-23 | $7700.00 | Window Closed / Lapsed |