US3863071A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Infrared measuring system with channel spectra negation
Assignee: ABB Automation Inc
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Filing: 1974-04-17
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Granted: 1975-01-28
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Expires: 1994-04-17
Abstract
Abstract Method and apparatus for measuring the constituent properties of a moving web or sheet of thin material utilizing a source of radiation emitting radiant energy in the infrared spectral band, a beam chopper for deriving separate beams of radiation of distinct wavelength bands, and means for directing the beams through the moving sheet. A detector detects the beams transmitted through the web. The first wavelength pass band is known as the absorption band; the other wavelength pass band is the reference band. The detected energy from the absorption and reference pass bands are utilized in a ratio computer whose output is indicative of the measure of the varying constituent. The reference position on the chopper contains material identical to the material, the properties of which are being measured to negate the effect of channel spectra in the measurement of thin films.
Inventors
- 👤 Angelo J Campanella
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 10:46
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/17; G01N21/25; G01N21/31; G01N21/314
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
163 words
In an infrared system for measuring the constitutent properties of a thin film material subject to the effect of channel spectra, wherein at least two beams of infrared energy are radiated, passed through or reflected from the material, and then detected, one of said beams being the reference signal and one being the absorption signal, the improvement being in the portion of the system for deriving the separate beams of energy and comprising: a. filter means positioned to limit the passband of all beams to a band where perceptible absorption exists in the film material to be measured, and b. a material sample, positioned in said system to attenuate only the beam corresponding to the reference signal by the passage of said beam through said material sample and absorption thereby, wherein said sample is: 1. made of the same material or a material spectrally similar to that to be measured, and 2. said sample is separate from the film material to be measured.
Claim 2
Dependent Claim
163 words
In an infrared system for measuring the constitutent properties of a thin film material subject to the effect of channel spectra, wherein at least two beams of infrared energy are radiated, passed through or reflected from the material, and then detected, one of said beams being the reference signal and one being the absorption signal, the improvement being in the portion of the system for deriving the separate beams of energy and comprising: a. filter means positioned to limit the passband of all beams to a band where perceptible absorption exists in the film material to be measured, and b. a material sample, positioned in said system to attenuate only the beam corresponding to the reference signal by the passage of said beam through said material sample and absorption thereby, wherein said sample is: 1. made of the same material or a material spectrally similar to that to be measured, and 2. said sample is separate from the film material to be measured.
Claim 3
Dependent Claim
11 words
said sample is separate from the film material to be measured.
Claim 4
Dependent Claim
11 words
said sample is separate from the film material to be measured.
Claim 5
Dependent Claim
34 words
In a system as claimed in claim 1 having a source of radiation in the infrared spectral band, and further comprising: a. a chopper positioned to intercept the radiation from said source, and having:
Claim 6
Dependent Claim
33 words
said material sample being positioned in at least one of said apertures to form the reference signal beam as such aperture moves into optical alignment with said source during movement of said chopper.
Claim 7
Dependent Claim
33 words
said material sample being positioned in at least one of said apertures to form the reference signal beam as such aperture moves into optical alignment with said source during movement of said chopper.
Claim 8
Dependent Claim
68 words
In a system as claimed in claim 2 having a motor for rotating said chpper and wherein: a. said chopper has four apertures formed therein for the sequential passage of infrared energy therethrough. b. said material sample is positioned in two non-adjacent apertures, and c. said two remaining apertures passing absorption signal beams as such apertures move into optical alignment with said source during rotation of said chopper.
Claim 9
Dependent Claim
34 words
In a system as claimed in claim 2 wherein: a. said filter means is positioned between said chopper and the material to be measured, and is in optical alignment with said source of radiation.
Claim 10
Dependent Claim
27 words
In a system as claimed in claim 4, wherein: a. said material to be measured is a film having a thickness no greater than approximately 0.001 inch.
Claim 11
Dependent Claim
38 words
In a system as claimed in claim 4 wherein: a. said reference signal beam after passage through said filter means and material sample has a wavelength above and a wavelength below the wavelength of said absorption signal beam.
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) | 1978-01-27 | 1978-07-29 | 1979-01-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-01-27 | 1982-07-29 | 1983-01-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-01-27 | 1986-07-29 | 1987-01-28 | $7700.00 | Window Closed / Lapsed |