
US Patent No: 4,830,494
Number of patents in Portfolio can not be more than 2000
Method and apparatus for measuring particles in a fluid
Stats
-
May 16, 1989
Issued date -
Jul 9, 1987
filing date -
07/072,228
serial no -
Expired
status
Importance
Abstract
Disclosed is a method and apparatus for measuring particles in a fluid by irradiating the fluid containing the particle with a laser beam and analyzing the laser light scattered by the particle to determine the characteristics of the particle. An elliptical laser beam is projected into a particle detection area in which the particles to be measured are caused to flow. The laser light scattered by the particle is received for photoelectric conversion into a time-series photoelectric signal in a direction along which the particle flows. The photoelectric signal is subjected to a moving average process to determine a time width during which the signal exceeds a predetermined level to cause the change in intensity of the scattered light. This change is recognized as a change in intensity caused by the passage of the particle through the particle detection area when the time width falls within a certain range.
First Claim
Related Publications
International Classification(s)
- [Classification Symbol]
- [Patents Count]
Cited Art
| Patent Info | (Count) | # Cites | Year |
|---|---|---|---|
|
|
|||
| 4,521,521 Particle reagent size distribution measurements for immunoassay | 21 | 1983 | |
|
|
|||
| 4,265,538 Optical sample cell for analysis of particles in liquid suspension | 28 | 1979 | |
|
|
|||
| 4,226,532 Device for granulometric analysis of particles in fluids | 5 | 1978 | |