Claims
- 1. A particle size analyzer based on laser diffraction method, comprising:
an irradiation optical system for irradiating laser beam to particles, said irradiation optical system having a semiconductor laser in an output beam wavelength of 300 to 500 nm as a light source; a measurement optical system situated near the irradiation optical system for measuring a space intensity distribution by receiving light diffracted/scattered by particles of the laser beam from the irradiation optical system, said measurement optical system including a plurality of light sensors disposed in an area of a predetermined front angle in an irradiating direction of the laser beam, a converging lens for converging light diffracted/scattered by a particle group to be measured, and a ring detector disposed at a focal position of the converging lens and formed of a plurality of independent conical light receiving surfaces in a shape of a ring, half ring or ¼ ring having different radii; and an operation portion connected to the measurement optical system for obtaining a particle size distribution of the particles from results measured by the measurement optical system.
- 2. A particle size analyzer based on laser diffraction method according to claim 1, wherein said converging lens receives the light diffracted/scattered by the particles in a front angle region of about 40°.
- 3. A particle size analyzer based on laser diffraction method according to claim 1, wherein the output beam wavelength of 300 to 500 nm by the semiconductor laser is less absorbed by blue color particles so that the particle size distribution in a range from a sub.sub-micron to several thousands μm is accurately obtained by measuring the space intensity distribution by light diffracted/scattered by the blue color particles.
- 4. A particle size analyzer based on laser diffraction method according to claim 1, further comprising a flow cell situated between the irradiation optical system and the measurement optical system for allowing the particles to flow therethrough.
- 5. A particle size analyzer based on laser diffraction method according to claim 4, further comprising a plurality of sideward scattered light sensors and the backward scattered light sensors situated adjacent the flow cell, and electrically connected to the measurement optical system.
Priority Claims (2)
Number |
Date |
Country |
Kind |
11-316031 |
May 1999 |
JP |
|
11-316030 |
May 1999 |
JP |
|
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This is a continuation application of patent application Ser. No. 09/699,338 filed on Oct. 31, 2000.
Continuations (1)
|
Number |
Date |
Country |
Parent |
09699338 |
Oct 2000 |
US |
Child |
10078449 |
Feb 2002 |
US |