US4240753A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for the quantitative determination of turbidities, especially of immune reactions
Assignee: Diamant Test Gesellschaft fuer Edelsteinpreufungen mbH
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Filing: 1978-11-14
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Granted: 1980-12-23
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Expires: 1998-11-14
Abstract
Abstract A nephelometer wherein a laser beam is split to define reference and sample beams. The reference beam is directed to a photodetector and the sample beam is passed through a test sample, the emerging beam being directed to a separate photodetector. The output from the respective photodetectors are compared via a comparator, and the comparator output is divided by the reference beam photodetector output to provide a recordable signal. Preferably, the photodetectors are dispersed within Ulbrecht type spheres whereby they are indirectly irradiated by the respective beam. The invention is particularly effective for measuring turbidities of very minute degree.
Inventors
- 👤 Gernot K. Bruck
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 17:36
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/17; G01N21/47; G01N21/49; G01N21/53; G01N21/534
Claims Analysis
Total Claims: 36
Claim 1
Independent Claim
157 words
A method for quantitative determination of very minute degrees of turbidities in a dilute test specimen comprising the steps of: a. irradiating a test specimen with a monochromatic laser beam along a first path; b. detecting and measuring the intensity of the laser beam emerging from the test specimen to provide a first measurement signal; c. diverting a defined portion of the laser beam from said first path to a lateral path prior to interception of said beam by the test specimen; d. detecting the intensity of said diverted laser beam along the lateral path to provide a reference signal; e. subtracting said reference signal from said first signal to provide an output signal; f. dividing said output signal by said reference signal to provide a quotient output signal corresponding to the true differential without variation effects originating with the laser light source; and, g. responding to said quotient output signal to provide a value for turbidity.
Claim 2
Independent Claim
157 words
A method for quantitative determination of very minute degrees of turbidities in a dilute test specimen comprising the steps of: a. irradiating a test specimen with a monochromatic laser beam along a first path; b. detecting and measuring the intensity of the laser beam emerging from the test specimen to provide a first measurement signal; c. diverting a defined portion of the laser beam from said first path to a lateral path prior to interception of said beam by the test specimen; d. detecting the intensity of said diverted laser beam along the lateral path to provide a reference signal; e. subtracting said reference signal from said first signal to provide an output signal; f. dividing said output signal by said reference signal to provide a quotient output signal corresponding to the true differential without variation effects originating with the laser light source; and, g. responding to said quotient output signal to provide a value for turbidity.
Claim 3
Dependent Claim
56 words
The method as claimed in claim 1 in which the said diverted portion of the laser beam and the laser beam emerging from the test specimen are each received by a respective photoresponsive element offset from the direct path of each respective beam so as to be activated by indirect, uniform irradiation of each respective beam.
Claim 4
Dependent Claim
54 words
The method as claimed in claim 2 wherein the diverted beam and the emerging beam are each introduced directly into a respective sphere having a uniform inner reflective surface and an entrance aperture and wherein the photoresponsive detector is positioned at the reflective surface and offset from the direct irradiation by the respective beam.
Claim 5
Dependent Claim
15 words
The method as claimed in claim 3 in which said laser beam is rotation polarized.
Claim 6
Dependent Claim
29 words
The method as claimed in claim 2 wherein the reference beam and the emerging beam are each measured by an indirectly irradiated photodetector directly irridiated by the respective beam.
Claim 7
Dependent Claim
26 words
The method as claimed in claim 2 in which the diverted beam intensity has a predetermined ratio relative to the beam intensity irradiating said test sample.
Claim 8
Dependent Claim
15 words
The method as claimed in claim 2 in which said laser beam is rotation polarized.
Claim 9
Dependent Claim
28 words
The method as claimed in claim 2 in which the ratio of the diverted beam intensity to the beam intensity which irradiates the test sample is about 50:50.
Claim 10
Dependent Claim
17 words
The method as claimed in claim 2 wherein said laser beam wavelength is in the visible range.
Claim 11
Dependent Claim
26 words
The method as claimed in claim 1 in which the diverted beam intensity has a predetermined ratio relative to the beam intensity irradiating said test sample.
Claim 12
Dependent Claim
28 words
The method as claimed in claim 10 in which the ratio of the diverted beam intensity to the beam intensity which irradiates the test sample is about 50:50.
Claim 13
Dependent Claim
15 words
The method as claimed in claim 11 in which said laser beam is rotation polarized.
Claim 14
Dependent Claim
29 words
The method as claimed in claim 11 wherein the reference beam and the emerging beam are each measured by an indirectly irradiated photodetector directly irridiated by the respective beam.
Claim 15
Dependent Claim
17 words
The method as claimed in claim 11 wherein said laser beam wavelength is in the visible range.
Claim 16
Dependent Claim
54 words
The method as claimed in claim 1 wherein the diverted beam and the emerging beam are each introduced directly into a respective sphere having a uniform inner reflective surface and an entrance aperture, and wherein the photoresponsive detector is positioned at the reflective surface and offset from the direct irradiation by the respective beam.
Claim 17
Dependent Claim
15 words
The method as claimed in claim 15 in which said laser beam is rotation polarized.
Claim 18
Dependent Claim
29 words
The method as claimed in claim 15 wherein the reference beam and the emerging beam are each measured by an indirectly irradiated photodetector directly irridiated by the respective beam.
Claim 19
Dependent Claim
17 words
The method as claimed in claim 15 wherein said laser beam wavelength is in the visible range.
Claim 20
Dependent Claim
28 words
The method as claimed in claim 1 in which the ratio of the diverted beam intensity to the beam intensity which irradiates the test sample is about 50:50.
Claim 21
Dependent Claim
15 words
The method as claimed in claim 1 in which said laser beam is rotation polarized.
Claim 22
Dependent Claim
17 words
The method as claimed in claim 1 wherein said laser beam wavelength is in the visible range.
Claim 23
Dependent Claim
34 words
The method as claimed in claim 1 wherein the reference beam and the emerging beam are each measured by an indirectly irradiated photodetector as opposed to a photodetector directly irradiated by the respective beam.
Claim 24
Dependent Claim
15 words
The method as claimed in claim 22 in which said laser beam is rotation polarized.
Claim 25
Dependent Claim
26 words
The method as claimed in claim 23 wherein the wavelength of said laser beam is selected to be in the range of 400 to 650 nanometers.
Claim 26
Dependent Claim
17 words
The invention as claimed in claim 24 in which the signal dividing device is a quotient amplifier.
Claim 27
Dependent Claim
49 words
The invention as claimed in claim 25 in which each of the detectors comprises an Ulbricht sphere type photometer having an entrance for receiving the beam and a photoresponsive device responsive to radiation in the interior of the sphere at a location offset from direct radiation of the beam.
Claim 28
Independent Claim
254 words
A device for quantitative determination of very minute degrees of turbidity in a dilute biological specimen or the like which comprises A. a laser light source arranged to provide a monochromatic laser beam along a first beam path; B. a specimen holder in the said path adapted to have the specimen disposed therein, the walls of said holder being substantially transparent to the laser beam; C. a first photoresponsive detector aligned with said path and disposed to receive the portion of the beam which has passed through the specimen holder directly and to provide a measurement signal as its output; D. a beam splitter in the path but before the specimen holder adapted to divert a substantial portion of the original beam along a lateral path; E. a second photoresponsive detector disposed to receive the portion of beam of said lateral path directly and provide a reference signal as its output; F. a differential amplifier having two inputs and an output channel; G. each detector having an output terminal which is connected to a different input of the differential amplifier; H. a signal dividing device connected to the output channel of the differential amplifier; I. the second detector also having its output connected to said signal dividing device and arranged so that the differential amplifier output is divided by the second detector output in order to provide a quotient output that corresponds to the true differential without the variation effects of said laser light source; and, J. means for responding to said quotient output.
Claim 29
Independent Claim
254 words
A device for quantitative determination of very minute degrees of turbidity in a dilute biological specimen or the like which comprises A. a laser light source arranged to provide a monochromatic laser beam along a first beam path; B. a specimen holder in the said path adapted to have the specimen disposed therein, the walls of said holder being substantially transparent to the laser beam; C. a first photoresponsive detector aligned with said path and disposed to receive the portion of the beam which has passed through the specimen holder directly and to provide a measurement signal as its output; D. a beam splitter in the path but before the specimen holder adapted to divert a substantial portion of the original beam along a lateral path; E. a second photoresponsive detector disposed to receive the portion of beam of said lateral path directly and provide a reference signal as its output; F. a differential amplifier having two inputs and an output channel; G. each detector having an output terminal which is connected to a different input of the differential amplifier; H. a signal dividing device connected to the output channel of the differential amplifier; I. the second detector also having its output connected to said signal dividing device and arranged so that the differential amplifier output is divided by the second detector output in order to provide a quotient output that corresponds to the true differential without the variation effects of said laser light source; and, J. means for responding to said quotient output.
Claim 30
Dependent Claim
52 words
The invention as claimed in claim 27 in which each of said detectors is of the type which has a photoresponsive element out of the path of its received incident beam and is activated by indirect, uniform irradiation of said incident beam as opposed to being directly irradiated by the respective beam.
Claim 31
Dependent Claim
17 words
The invention as claimed in claim 28 in which the signal dividing device is a quotient amplifier.
Claim 32
Dependent Claim
50 words
The invention as claimed in claim 29 in which each of the detectors comprises an Ulbricht sphere type photometer having an entrance for receiving the beam and a photoresponsive device responsive to radiation in the interior of the sphere at a location offset from the direct path of the beam.
Claim 33
Dependent Claim
26 words
The invention as claimed in claim 27 and means for shielding said beam paths to protect them from light entering from the exterior of said device.
Claim 34
Dependent Claim
50 words
The invention as claimed in claim 31 in which each of the detectors comprises an Ulbricht sphere type photometer having an entrance for receiving the beam and a photoresponsive device responsive to radiation in the interior of the sphere at a location offset from the direct path of the beam.
Claim 35
Dependent Claim
16 words
The invention as claimed in claim 27 in which said beam splitter is a semi-transparent mirror.
Claim 36
Dependent Claim
19 words
The invention as claimed in claim 27 in which the beam provided by said laser light source is polarized.
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) | 1983-12-23 | 1984-06-23 | 1984-12-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-12-23 | 1988-06-23 | 1988-12-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-12-23 | 1992-06-23 | 1992-12-23 | $7700.00 | Window Closed / Lapsed |