US4009443A
Expired / Lapsed
US
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Method and apparatus for providing primary coincidence correction during particle analysis utilizing time generation techniques
Assignee: Coulter Electronics Inc
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Filing: 1975-04-03
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Granted: 1977-02-22
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Expires: 1995-04-03
Abstract
Abstract A method and apparatus for correcting a particle pulse count subject to coincidence error is disclosed wherein particle pulses, developed in response to passage of particles in a particulate system through a sensing zone, are counted for a predetermined period of time. The predetermined period of time is increased or extended in response to each pulse counted by a time increment that is related to a characteristic of the counted pulse, such as the pulse width, duration, or amplitude. The total additional time period allows the counting of additional particle pulses such that the total count at the end of the extended time period is an error corrected count for the number of particles detected in the predetermined time period.
Inventors
- 👤 Wallace H. Coulter
- 👤 Walter R. Hogg
- 👤 Millard D. Longman, Jr.
- 👤 Stephen Campbell
- 👤 Edward Neal Doty
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 11:46
CPC Classifications
H; H03; H03K; H03K21/00; H03K21/02; G; G01; G01N; G01N15/00; G01N15/10; G01N15/1031; G01N15/12; G01N15/131; G01N15/132
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
59 words
A method for correcting a particle pulse count subject to coincidence error including the steps of: counting the particle pulses received for a predetermined period of time, increasing said predetermined period of time by a fixed time increment in response to each pulse, the fixed time increment being a function of coincidence error and therefore related to pulse width.
Claim 2
Independent Claim
59 words
A method for correcting a particle pulse count subject to coincidence error including the steps of: counting the particle pulses received for a predetermined period of time, increasing said predetermined period of time by a fixed time increment in response to each pulse, the fixed time increment being a function of coincidence error and therefore related to pulse width.
Claim 3
Dependent Claim
38 words
The method of claim 1 wherein the step of counting the particle pulses for a predetermined period of time includes the step of detecting particle pulses in excess of a first amplitude and counting said detected particle pulses.
Claim 4
Independent Claim
72 words
A method for automatically correcting a particle pulse count subject to coincidence error including the steps of measuring a predetermined time period during which time period said received particle pulses are counted and inhibiting measurement of said predetermined time period by a fixed time increment in response to each received particle pulse said fixed time increment being related to the characteristics of the particle pulse received and therefore to the coincidence error.
Claim 5
Independent Claim
72 words
A method for automatically correcting a particle pulse count subject to coincidence error including the steps of measuring a predetermined time period during which time period said received particle pulses are counted and inhibiting measurement of said predetermined time period by a fixed time increment in response to each received particle pulse said fixed time increment being related to the characteristics of the particle pulse received and therefore to the coincidence error.
Claim 6
Independent Claim
131 words
An apparatus for automatically correcting a particle pulse count subject to coincidence error wherein the particle pulses are developed in response to passage of particles in a particulate system through a particle sensing device, said apparatus including in combination, timer means operative to count the particle pulses for a predetermined period of time, and control means coupled to said timer means and operative to increase said predetermined period of time by a time increment in response to each particle pulse, said control means including detection circuit means coupled to said particle sensing device and operative in response to each particle pulse to develop said control signal for a fixed duration, said fixed duration being selected such that it is related to the particle pulse characteristics and therefore to the coincidence error.
Claim 7
Independent Claim
131 words
An apparatus for automatically correcting a particle pulse count subject to coincidence error wherein the particle pulses are developed in response to passage of particles in a particulate system through a particle sensing device, said apparatus including in combination, timer means operative to count the particle pulses for a predetermined period of time, and control means coupled to said timer means and operative to increase said predetermined period of time by a time increment in response to each particle pulse, said control means including detection circuit means coupled to said particle sensing device and operative in response to each particle pulse to develop said control signal for a fixed duration, said fixed duration being selected such that it is related to the particle pulse characteristics and therefore to the coincidence error.
Claim 8
Dependent Claim
51 words
The apparatus of claim 4 further including detection means coupling said particle sensing device to said timer means and control means, said detection means operative in response to particle pulses in excess of a first amplitude to develop detection signals and couple said signals to said timer means and control means.
Claim 9
Dependent Claim
42 words
The apparatus of claim 4 wherein said timer means includes, counter means for counting said particle pulses, and a timer circuit coupled to said counter means for enabling said counter means to count said particle pulses for said predetermined period of time.
Claim 10
Dependent Claim
66 words
The apparatus of claim 6 wherein said timer circuit generates a timing signal for said predetermined time period, said counter means including gating means coupled to said particle sensing device and said timer circuit and operative in response to said timing signal and each particle pulse detected to develop a gating signal, and a counter circuit coupled to said gating means for counting each gating signal.
Claim 11
Dependent Claim
13 words
The apparatus of claim 7 wherein said gating means is an AND gate.
Claim 12
Dependent Claim
39 words
The apparatus of claim 4 wherein said detection circuit includes monostable means operative in response to each particle pulse to develop said fixed duration control signal said monostable means including means for selecting the period of said fixed duration.
Claim 13
Dependent Claim
64 words
The apparatus of claim 9 wherein said detection circuit includes a trailing edge detection circuit coupled to said particle sensing device and operative in response to the trailing edge of each of said particle pulses to develop a detection pulse, said monostable means being coupled to said trailing edge detection circuit and operative in response to each detection pulse to develop said control signal.
Claim 14
Dependent Claim
128 words
In a particle analyzer subject to coincidence error wherein particle pulses are developed in response to passage of particles in a particulate system through a sensing zone, the improvement comprising, detection means operative in response to receipt of particle pulses to develop detection signals having a duration equal to the period said particle pulses exceed a predetermined amplitude, timer means coupled to said detector means and operative to count said detection signals for a predetermined period of time, and control means coupled to said detection means and said timer means and operative to increase said predetermined period of time by a time increment in response to each detection signal, said time increment duration being related to a characteristic of said detection signal and therefore to said coincidence error.
Claim 15
Dependent Claim
128 words
In a particle analyzer subject to coincidence error wherein particle pulses are developed in response to passage of particles in a particulate system through a sensing zone, the improvement comprising, detection means operative in response to receipt of particle pulses to develop detection signals having a duration equal to the period said particle pulses exceed a predetermined amplitude, timer means coupled to said detector means and operative to count said detection signals for a predetermined period of time, and control means coupled to said detection means and said timer means and operative to increase said predetermined period of time by a time increment in response to each detection signal, said time increment duration being related to a characteristic of said detection signal and therefore to said coincidence error.
Claim 16
Dependent Claim
32 words
The apparatus of claim 11 wherein said control means is operative to increase said predetermined period of time by a fixed time increment in response to the termination of each detection signal.
Claim 17
Dependent Claim
51 words
The apparatus of claim 12 wherein said control means is further operative to increase said predetermined time period by a second time increment in response to the termination of each detection signal, said second time increment having a duration which is a function of the repetition rate of said particle pulses.
Claim 18
Dependent Claim
130 words
In a particle analyzer subject to coincidence error wherein particle pulses are developed in response to passage of particles in a particulate system through a sensing zone and wherein the coincidence error is a function of particle passage time the improvement comprising; detection means operative in response to receipt of particle pulses in excess of a predetermined amplitude to develop detection pulses, timer means coupled to said detection means and operative to count said detection signals for a predetermined period of time, and control means coupled to said detection means and said timer means and operative in response to each detection signal to increase said predetermined period of time by a fixed time increment, said time increment duration being a function of particle passage time and therefore of coincidence error.
Claim 19
Dependent Claim
130 words
In a particle analyzer subject to coincidence error wherein particle pulses are developed in response to passage of particles in a particulate system through a sensing zone and wherein the coincidence error is a function of particle passage time the improvement comprising; detection means operative in response to receipt of particle pulses in excess of a predetermined amplitude to develop detection pulses, timer means coupled to said detection means and operative to count said detection signals for a predetermined period of time, and control means coupled to said detection means and said timer means and operative in response to each detection signal to increase said predetermined period of time by a fixed time increment, said time increment duration being a function of particle passage time and therefore of coincidence error.
Claim 20
Independent Claim
111 words
An apparatus for automatically correcting a particle pulse count subject to coincidence error wherein the particle pulses are developed in response to passage of particles in a particulate system through a particle sensing device and wherein the coincidence error is related to particle passage time through said sensing device, said apparatus including in combination, timer means operative to count the particle pulses for a predetermined period of time, and control means coupled to said timer means and operative to increase said predetermined period of time by a fixed time increment in response to each particle pulse, said time increment duration being related to particle passage time and therefore to coincidence error.
Claim 21
Independent Claim
111 words
An apparatus for automatically correcting a particle pulse count subject to coincidence error wherein the particle pulses are developed in response to passage of particles in a particulate system through a particle sensing device and wherein the coincidence error is related to particle passage time through said sensing device, said apparatus including in combination, timer means operative to count the particle pulses for a predetermined period of time, and control means coupled to said timer means and operative to increase said predetermined period of time by a fixed time increment in response to each particle pulse, said time increment duration being related to particle passage time and therefore to coincidence error.
Claim 22
Dependent Claim
42 words
The apparatus of claim 15 wherein said timer means include, counter means for counting said particle pulses, and a timer circuit coupled to said counter means for enabling said counter means to count said particle pulses for said predetermined period of time.
Claim 23
Dependent Claim
57 words
The apparatus of claim 16 wherein said control means include detection circuit means coupled to said particle sensing device and operative in response to each particle pulse to develop said control signal for a fixed duration, said fixed duration being selected such that it is related to the particle passage time and therefore to the coincidence error.
Claim 24
Dependent Claim
155 words
The apparatus of claim 17 wherein said timer circuit includes, a clock oscillator for developing clock pulses, gate means coupled to said clock oscillator and operative to pass said clock pulses therethrough, a counter circuit coupled to said gate means for counting a particular number of said clock pulses in said predetermined time period and for developing an enable signal during said counting for enabling said counter means, stop-start control means coupled to said gate means and counter circuit, said stop-start control means operative when disabled to inhibit passage of said clock pulses through said gate means, to inhibit counting by said counting circuit and to inhibit said enable signal, said stop-start circuit operative when enabled to become disabled in response to termination of said enable signal, said gate means being coupled to said control means and operative in response to said control signal to inhibit passage of said clock pulses through said gate means.
Claim 25
Dependent Claim
13 words
The apparatus of claim 18 wherein said stop-start control means include bistable means.
Claim 26
Dependent Claim
39 words
The apparatus of claim 17 wherein said detection circuit includes monostable means operative in response to each particle pulse to develop said fixed duration control signal said monostable means including means for selecting the period of said fixed duration.
Claim 27
Dependent Claim
64 words
The apparatus of claim 20 wherein said detection circuit includes a trailing edge detection circuit coupled to said particle sensing device and operative in response to the trailing edge of each of said particle pulses to develop a detection pulse, said monostable means being coupled to said trailing edge detection circuit and operative in response to each detection pulse to develop said control signal.
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) | 1980-02-22 | 1980-08-23 | 1981-02-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-02-22 | 1984-08-23 | 1985-02-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-02-22 | 1988-08-23 | 1989-02-22 | $7700.00 | Window Closed / Lapsed |