Process and apparatus for analyzing cells

• US 5,088,816 A
• Filed: 03/06/1990
• Issued: 02/18/1992
• Est. Priority Date: 09/19/1989
• Status: Expired

• Current Assignee: TOA Medical Electronics Company Limited
• Original Assignee: Toa Medical Electronics Co., Ltd.
• Inventors: Tomioka, Atuo, Maeda, Tadashi, Nakagawa, Masayuki
• Primary Examiner(s): Rosenberger, Richard A.
• Application Number:
  US07/489,463
• Time in Patent Office: 714 Days
• Field of Search: 356/39, 356/246
• US Class Current: 356/39
• CPC Class Codes: G01N 15/1404 Handling flow, e.g. hydrodynamic focusing
• CPC Class Codes: G01N 2015/1411 Features of sheath fluids
• CPC Class Codes: G01N 2021/8557 Special shaping of flow, e.g. using a by-pass line, jet flow, curtain flow
• CPC Class Codes: G01N 33/497 of gaseous biological material, e.g. breath

Abstract

A cell analyzing system flows a liquid to be tested and a sheath liquid through a flattened flow passage. An image of the flattened flow passage is formed at two different magnifications. The thickness of the liquid to be tested in the flattened flow passage is changed between the two different magnifications to maintain this thickness at a value smaller than a depth of field of the apparatus forming the image. The thickness of the liquid to be tested is changed by changing its flow relationship to the sheath liquid.

Claims

1. A process for classifying and counting ingredients of a liquid to be tested, comprising:

flowing said liquid to be tested in a flattened path;

surrounding said liquid to be tested in said flattened path with a sheath liquid;

impinging a light on said flattened path;

photographing said flattened path at a first magnification;

photographing said flattened path at a second magnification; and

changing a thickness of said liquid to be tested in said flattened path when photographing at said first and second magnifications, whereby said thickness remains less than a depth of field of a lens used in said photographing.

2. A process according to claim 1, wherein the step of changing a thickness includes changing a flow rate of at least one of said liquid to be tested and said sheath liquid.

3. A process according to claim 1, further comprising:

adjusting an amount of said light according to said first and second magnifications.

4. A process according to claim 1, further comprising diffusing said light during photographing at one of said first and second magnifications, and not at the other thereof.

5. A process according to claim 4, wherein the one of said first and second magnifications is a lower magnification.

6. A process according to claim 1, further comprising:

simultaneously adjusting an intensity of said light, said thickness, and said magnification to attain a sharp image of particles in said liquid to be tested.

7. A cell analyzing system comprising:

a strobe for emitting flashes of a light;

at least one lens;

said at least one lens being effective for transforming said light into a parallel light;

an iris receiving said parallel light;

adjustable means for adjusting an opening of said iris;

a condenser lens receiving light from said iris;

a flow cell;

a reduced flow passage in said flow cell;

said reduced flow passage including a thickness which narrows gradually in a downstream direction;

a flattened flow passage;

said flattened flow passage communicating with a downstream side of said reduced flow passage;

a nozzle having an end facing in a downward direction toward an upstream side of said reduced flow passage;

a test liquid supply means;

said test liquid supply means being connected to said nozzle;

said test liquid supply means including means for changing a supply quantity of said liquid to be tested;

a sheath liquid supply means connected to an upstream side of said reduced flow passage;

at least said flattened flow passage being transparent;

said light from said condenser lens passing through said flattened flow passage, including liquids therein;

an objective lens disposed behind said flow cell;

at least first and second projection lenses;

said at least first and second projection lenses having first and second different magnifications;

means for selectably disposing said first and second projection lenses in a path of light from said flattened flow path;

means for photographing an image from a selected one of said first and second projection lenses; and

means for controlling a flow such that a thickness of said test liquid differs for different magnifications.

8. A system according to claim 7, wherein said means for selectably disposing includes means for changing a path length of said light, whereby a sharp focus is maintained at said first and second magnifications.

9. A system according to claim 7, further comprising means for changing a thickness of said test liquid in said flattened flow passage.

10. A system according to claim 9 wherein said means for changing a thickness includes changing a flow of at least one of said test liquid and said sheath liquid.

11. A system according to claim 7, further comprising means for diffusing said light from said strobe during at least a lower of said first and second magnifications.

12. A system according to claim 7, wherein the means for diffusing includes means for diffusing said light only during said lower of said first and second magnifications.

13. A method for photographing a test liquid comprising:

flowing said test liquid through a reduced flow passage;

flowing a sheath liquid through said reduced flow passage;

flowing said test liquid and said sheath liquid from said reduced flow passage through a flattened flow passage;

passing a parallel light through said flattened flow passage;

forming an image of said parallel light passing through said flattened flow passage;

controlling a thickness of said test liquid in said flattened flow passage to a value permitting said image to be sharp;

the step of controlling including changing a flow relationship of said test liquid and said sheath liquid;

changing a magnification of said image; and

changing a thickness of said test liquid in said flattened flow passage to a value within a depth of field of an apparatus forming said image.

14. A method for photographing a test liquid comprising:

flowing said test liquid through a reduced flow passage;

flowing a sheath liquid through said reduced flow passage;

flowing said test liquid and said sheath liquid from said reduced flow passage through a flattened flow passage;

passing a parallel light through said flattened flow passage;

forming an image of said parallel light passing through said flattened flow passage;

controlling a thickness of said test liquid in said flattened flow passage to a value permitting said image to be sharp; and

the step of controlling including changing a flow relationship of said test liquid and said sheath liquid;

forming a first image at a first magnification;

controlling said thickness to a first value within a depth of field at said first magnification;

forming a second image at a second magnification; and

controlling said thickness to a second value within a depth of field at said second magnification.