Particle analyzer

• US 5,633,503 A
• Filed: 11/23/1994
• Issued: 05/27/1997
• Est. Priority Date: 11/26/1993
• Status: Expired due to Fees

• Current Assignee: Toa Medical Electronics Co., Ltd.
• Original Assignee: Toa Medical Electronics Co., Ltd.
• Inventors: Kosaka, Tokihiro
• Primary Examiner(s): Tokar, Michael J.
• Assistant Examiner(s): Tyler, Virgil O.
• Application Number:
  US08/346,268
• Time in Patent Office: 916 Days
• Field of Search: 250/458.1, 250/459.1, 250/461.2, 250/455.11
• US Class Current: 250/458.1
• CPC Class Codes: G01N 15/1404 Handling flow, e.g. hydrodynamic focusing

Abstract

A particle analyzer includes a flow cell for enclosing a sample liquid containing particles in a sheathed flow to form a flat flow of the sample liquid; an exciting light source for emitting light for exciting fluorescence to irradiate the particle in the flat flow; a capturing device for capturing a fluorescent image of the particle when the particle reaches a predetermined position of the flat flow, the exciting light source and the capturing device being disposed so that a capturing optical axis of the capturing device is perpendicular to a surface of the flat flow and orthogonal to a light emitting optical axis of the exciting light source; and a shutter device for allowing the capturing device to receive the fluorescence from the particle for a predetermined period of time.

Claims

1. A particle analyzer comprising:

a flow cell for enclosing a sample liquid containing particles in a sheathed flow to form a flat flow of the sample liquid;

exciting light source means for emitting light for exciting fluorescence to irradiate the particle in the flat flow;

an illumination light source for emitting illumination light to irradiate the particle in the flat flow;

a sensor for receiving the illumination light passing through the particle to capture an image of the particle;

monitoring means for determining whether two or more particles are passing through the flat flow imaged onto said sensor; and

capturing means for capturing a fluorescent image of the particle when the particle reaches a predetermined position of the flat flow.

2. A particle analyzer according to claim 1 further comprising:

a shutter which allows the capturing means to receive the fluorescence from the particle for a predetermined period of time;

light detection means for detecting light coming from the particle irradiated with the exciting light;

control means for controlling an operational timing of the shutter based on at least one of a detection signal from the light detection means and an image signal of said sensor; and

analyzing means for analyzing the particle based on at least one of an image signal from each of the capturing means and said sensor and the detection signal from the light detection means.

3. A particle analyzer according to claim 2 wherein the light coming from the particle is at least one of forward scatter light, side scatter light, forward fluorescence and side fluorescence.

4. A particle analyzer according to claim 1 further comprising:

a shutter which allows the capturing means to receive the fluorescence from the particle for a predetermined period of time;

control means for controlling an operation timing of the shutter based on an image signal from the sensor; and

analyzing means for analyzing the particle based on at least one of image signals from the capturing means and the sensor.

5. A particle analyzer according to claim 2 wherein the capturing means captures a fluorescent image obtained from one surface of the flat flow and light detection means detects the light obtained from the other surface of the flat flow.

6. A particle analyzer according to claim 1, wherein said sensor is a one dimensional image sensor capturing an image of the particle by scanning across the flat flow.

7. A particle analyzer according to claim 6, wherein said analyzing means further comprises means for calculating physical characteristics of the particle, said analyzing means ignoring calculated physical characteristics when two or more particles are indicated by said monitoring means.

8. A particle analyzer according to claim 4, wherein said analyzing means comprises means for calculating physical characteristics of the particle.

9. A particle analyzer according to claim 1, wherein said monitoring means monitors an area upstream of said predetermined position.

10. A method of analyzing particles in a sample liquid comprising the steps of:

enclosing the sample liquid in a sheathed flow to form a flat flow having a first side and a second side orthogonal to said first side;

irradiating particles in the first side of the flat flow with exciting light;

irradiating particles in the flat flow with illuminating light;

imaging the illuminating light passing through the flat flow onto a sensor;

determining whether two or more particles are passing through the flat flow imaged onto said sensor; and

capturing an image of the second side of the flat flow including a fluorescent image of a particle irradiated by the exciting light when the particle reaches a predetermined position.

11. A method according to claim 10, further comprising:

detecting light coming from the particle irradiated with the exciting light;

controlling, in accordance with the detecting step, an operational timing of a shutter for allowing the capturing step to receive fluorescence from the particle for a predetermined period of time; and

analyzing the particle based on at least one of an image signal from the capturing step and a detection signal from the detecting step.

12. A method according to claim 10, further comprising:

analyzing the particles based on at least one of image signals from the capturing step and the imaging step.

13. A method according to claim 10, wherein said imaging step includes imaging the illuminating light onto a one dimensional image sensor.

14. A method according to claim 12, further comprising ignoring said analyzing step based on an image signal from the capturing step when the determining step determines two or more particles are present.

15. A method according to claim 12, further comprising calculating physical characteristics of a particle in the flat flow imaged onto said one dimensional image sensor.

18. A method according to claim 10, wherein said imaging step includes imaging an area upstream of said predetermined position.

16. A particle analyzer comprising:

a flow cell for enclosing a sample liquid containing particles in a sheathed flow to form a flat flow of the sample liquid;

an exciting light source for emitting light for exciting fluorescence to irradiate the particle in the flat flow;

capturing means for capturing a fluorescent image of the particle when the particle reaches a predetermined position of the flat flow;

a shutter which allows the capturing means to receive the fluorescence from the particle for a predetermined period of time;

an illumination light source for emitting illumination light to irradiate the particle in the flat flow;

a sensor receiving the illumination light passing through the particle to capture an image of the particle;

control means for controlling an operation timing of the shutter based on an image signal from said sensor; and

analyzing means for analyzing the particle based on at least one of image signals from the capturing means and said sensor, said analyzing means including means for calculating physical characteristics of the particle.

19. A particle analyzer according to claim 16, wherein said physical characteristics include at least one of absorbency and area.

17. A method of analyzing particles in a sample liquid comprising the steps of:

enclosing the sample liquid in a sheathed flow to form a flat flow;

irradiating particles in the flat flow with exciting light;

capturing a fluorescent image of a particle irradiated by the exciting light;

irradiating particles in the flat flow with illuminating light;

imaging the illuminating light passing through the flat flow onto a sensor; and

analyzing the particles based on at least one of image signals from the capturing step and the imaging step, said analyzing step including, said analyzing step including calculating physical characteristics of a particle in the flat flow imaged onto said sensor.