US4768879A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for measuring the size of objects in a fluid medium
Assignee: Dow Chemical Co
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Filing: 1986-06-17
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Granted: 1988-09-06
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Expires: 2006-06-17
Abstract
Abstract A method for determining the size of moving objects present in a transparent or translucent fluid medium comprises illuminating a zone of the suspension with monochromatic light, collecting scattered light having a wavelength characteristic of the objects or of the medium, and measuring the intensity and variations in intensity of the collected light. The data thus obtained may be compared with data obtained from corresponding measurements of corresponding mediums containing corresponding objects of known size.
Inventors
- 👤 Richard D. McLachlan
- 👤 Ray W. Chrisman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 15:03
CPC Classifications
G; G01; G01N; G01N15/00; G01N15/02; G01N15/0205; G01N21/00; G01N21/17; G01N21/47; G01N2021/4704; G01N2021/4709; G01N21/62; G01N21/63; G01N21/64; G01N2021/6417; G01N21/65; G01N2021/651; G01N2021/653; G01N2021/656; G01N21/84; G01N21/85; G01N21/8507
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
133 words
An in-situ method for determining the size of objects present and moving in a translucent or transparent fluid medium comprising: a. illuminating with monochromatic light a zone of said medium traversed by said objects; b. collecting light scattered selectively by said objects or said medium and having a wavelength that is characteristic of the composition of said objects or said medium; c. measuring a selected plurality of times the intensity of the collected light over a plurality of spaced intervals of time; d. calculating the mean intensity and the variance in the intensities of the scattered light collected during said time intervals; and e. comparing data obtained from such measurements and calculations with values obtained from the making of corresponding measurements and calculations of corresponding objects present and moving in a corresponding medium.
Claim 2
Dependent Claim
133 words
An in-situ method for determining the size of objects present and moving in a translucent or transparent fluid medium comprising: a. illuminating with monochromatic light a zone of said medium traversed by said objects; b. collecting light scattered selectively by said objects or said medium and having a wavelength that is characteristic of the composition of said objects or said medium; c. measuring a selected plurality of times the intensity of the collected light over a plurality of spaced intervals of time; d. calculating the mean intensity and the variance in the intensities of the scattered light collected during said time intervals; and e. comparing data obtained from such measurements and calculations with values obtained from the making of corresponding measurements and calculations of corresponding objects present and moving in a corresponding medium.
Claim 3
Dependent Claim
17 words
The method according to claim 1 including transmitting the light to said zone by optical fiber means.
Claim 4
Dependent Claim
15 words
The method according to claim 1 including collecting the scattered light by optical fiber means.
Claim 5
Dependent Claim
42 words
The method according to claim 1 including illuminating said zone and collecting the scattered light by means of a probe immersed in said medium, said probe having therein means for transmitting the illuminating light and means for transmitting the collected scattered light.
Claim 6
Dependent Claim
19 words
The method according to claim 1 including illuminating said zone by light emitted from a continuous wave gas laser.
Claim 7
Dependent Claim
17 words
The method according to claim 1 including measuring the intenstiy of said collected light by spectrophotometer means.
Claim 8
Dependent Claim
29 words
The method of claim 1 including filtering the collected light prior to measuring the intensity and to limit the light utilized for such measurements to that having said wavelength.
Claim 9
Dependent Claim
12 words
The method according to claim 1 wherein said objects comprise solid particles.
Claim 10
Dependent Claim
12 words
The method according to claim 1 wherein said objects comprise liquid droplets.
Claim 11
Dependent Claim
12 words
The method according to claim 1 wherein said objects comprise gas bubbles.
Claim 12
Dependent Claim
17 words
The method according to claim 1 wherein the illuminating light is scattered due to the Raman effect.
Claim 13
Dependent Claim
15 words
The method according to claim 1 wherein the illuminating light is scattered due to fluorescence.
Claim 14
Dependent Claim
16 words
The method according to claim 1 wherein the intervals of time are of substantially uniform duration.
Claim 15
Dependent Claim
15 words
The method according to claim 13 wherein the space between successive intervals is substantially uniform.
Claim 16
Dependent Claim
135 words
An in-situ method for determining the size of objects present and moving in a translucent or transparent fluid medium comprising: a. illuminating with monochromatic light a zone of said medium traversed by said objects; b. collecting light scattered selectively by said objects or said medium and having a wavelength that is characteristic of the composition of said objects or said medium; c. measuring a selected plurality of times the intensity of the collected light over a plurality of spaced intervals of time; d. calculating the mean intensity and the variance in intensities of the scattered light collected during said intervals of time; and e. comparing the measured intensity and variance thereof with calibration data obtained by performing the above steps a-d using corresponding objects of known size present and moving in a corresponding fluid medium.
Claim 17
Dependent Claim
135 words
An in-situ method for determining the size of objects present and moving in a translucent or transparent fluid medium comprising: a. illuminating with monochromatic light a zone of said medium traversed by said objects; b. collecting light scattered selectively by said objects or said medium and having a wavelength that is characteristic of the composition of said objects or said medium; c. measuring a selected plurality of times the intensity of the collected light over a plurality of spaced intervals of time; d. calculating the mean intensity and the variance in intensities of the scattered light collected during said intervals of time; and e. comparing the measured intensity and variance thereof with calibration data obtained by performing the above steps a-d using corresponding objects of known size present and moving in a corresponding fluid medium.
Claim 18
Dependent Claim
16 words
The method according to claim 16 wherein the intervals of time are of substantially uniform duration.
Claim 19
Dependent Claim
15 words
The method according to claim 16 wherein the space between successive intervals is substantially uniform.
References Cited (Backward Citations)
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1991-09-06 | 1992-03-07 | 1992-09-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-09-06 | 1996-03-07 | 1996-09-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-09-06 | 2000-03-07 | 2000-09-06 | $7700.00 | Window Closed / Lapsed |