US3923397A
Expired / Lapsed
US
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Hematocrit measuring method
Assignee: Individual
•
Filing: 1974-05-29
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Granted: 1975-12-02
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Expires: 1994-05-29
Abstract
Abstract A method for measuring a hematocrit ratio for a sample of blood comprises the steps of passing electromagnetic energy through the blood sample, measuring a characteristic representative of the amount of energy absorbed by the sample, and computing the hematocrit ratio by applying a proportionality factor to the measured characteristic of absorbed energy.
Inventors
- 👤 Reginald C Shuck
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 19:50
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/17; G01N21/59
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
74 words
A method for measuring a hematocrit ratio for a diluted blood sample, comprising the steps of: passing electromagnetic energy through said blood sample; measuring a characteristic representative of the amount of said energy absorbed by said sample; determining a proportionality factor by dividing the hematocrit of a known blood sample by said characteristic of said known sample; and computing said hematocrit ratio by applying said proportionality factor to said measured characteristic of absorbed energy.
Claim 2
Independent Claim
74 words
A method for measuring a hematocrit ratio for a diluted blood sample, comprising the steps of: passing electromagnetic energy through said blood sample; measuring a characteristic representative of the amount of said energy absorbed by said sample; determining a proportionality factor by dividing the hematocrit of a known blood sample by said characteristic of said known sample; and computing said hematocrit ratio by applying said proportionality factor to said measured characteristic of absorbed energy.
Claim 3
Dependent Claim
21 words
The method recited in claim 1 further comprising the step of centrifuging said known sample to determine said hematocrit ratio thereof.
Claim 4
Dependent Claim
38 words
The method recited in claim 1 wherein said characteristic of said known sample is determined by: passing electromagnetic energy through said known sample; and measuring a characteristic representative of the amount of energy absorbed by said known sample.
Claim 5
Dependent Claim
26 words
The method recited in claim 1 further comprising the step Of diluting said blood sample with a saline solution prior to passing said electromagnetic energy therethrough.
Claim 6
Dependent Claim
15 words
The method recited in claim 4 wherein said saline solution comprises a physiological saline solution.
Claim 7
Dependent Claim
15 words
The method recited in claim 1 wherein said electromagnetic energy comprises a beam of light.
Claim 8
Dependent Claim
28 words
The method recited in claim 6 wherein said absorbance characteristic measuring step comprises comparing an unobstructed beam of said light with said beam passing through said blood sample.
Claim 9
Independent Claim
107 words
A method for measuring a hematocrit ratio for a blood sample, comprising the steps of: diluting said sample; passing a beam of light through said sample; measuring a characteristic representative of the amount of light absorbed by said sample; measuring the hematocrit ratio of a standard sample by a known technique; passing a beam of light through said standard sample; measuring a characteristic representative of the amount of energy absorbed by said standard sample; and calculating the hematocrit ratio of said sample by dividing said standard sample hematocrit ratio by the absorbance characteristic thereof and multiplying the resulting ratio by the absorbent characteristic measured for said sample.
Claim 10
Independent Claim
107 words
A method for measuring a hematocrit ratio for a blood sample, comprising the steps of: diluting said sample; passing a beam of light through said sample; measuring a characteristic representative of the amount of light absorbed by said sample; measuring the hematocrit ratio of a standard sample by a known technique; passing a beam of light through said standard sample; measuring a characteristic representative of the amount of energy absorbed by said standard sample; and calculating the hematocrit ratio of said sample by dividing said standard sample hematocrit ratio by the absorbance characteristic thereof and multiplying the resulting ratio by the absorbent characteristic measured for said sample.
Claim 11
Independent Claim
79 words
A method for measuring a hematocrit ratio for a blood sample, comprising the steps of: passing a beam of light energy through said sample; measuring the amount of said light energy transmitted through said sample; and computing said hematocrit ratio by applying a proportionality factor to said measurement of transmitted light energy by the following expression: H K (2 - log10 T) where: H hematocrit sought to be measured; T measured transmitted light energy; and K said proportionality factor.
Claim 12
Independent Claim
79 words
A method for measuring a hematocrit ratio for a blood sample, comprising the steps of: passing a beam of light energy through said sample; measuring the amount of said light energy transmitted through said sample; and computing said hematocrit ratio by applying a proportionality factor to said measurement of transmitted light energy by the following expression: H K (2 - log10 T) where: H hematocrit sought to be measured; T measured transmitted light energy; and K said proportionality factor.
Claim 13
Dependent Claim
21 words
The method recited in claim 9 further comprising the step of diluting said blood sample prior to said beam passing step.
Claim 14
Dependent Claim
23 words
The method recited in claim 10 wherein said diluting step comprises adding an amount of a physiological saline solution to said blood sample.
Claim 15
Dependent Claim
82 words
The method recited in claim 11 werhein said proportionality factor is determined by: passing a beam of light energy through a known blood sample diluted with said saline solution; measuring the amount of said light energy transmitted through said known sample; and measuring the hematocrit of said known sample by a known technique; and computing said proportionality factor by employing said hematocrit and transmission measurements in that expression set forth in claim 10 above and solving said expression for said proportionality factor.
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) | 1978-12-01 | 1979-06-02 | 1979-12-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-01 | 1983-06-02 | 1983-12-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-01 | 1987-06-02 | 1987-12-02 | $7700.00 | Window Closed / Lapsed |