Apparatus and method for analyzing particle images including measuring at a plurality of capturing magnifications

• US 5,721,433 A
• Filed: 11/03/1995
• Issued: 02/24/1998
• Est. Priority Date: 11/04/1994
• Status: Expired due to Term

• Current Assignee: Toa Medical Electronics Co., Ltd.
• Original Assignee: Toa Medical Electronics Co., Ltd.
• Inventors: Kosaka, Tokihiro
• Primary Examiner(s): Westin, Edward P.
• Assistant Examiner(s): PYO, KEVIN K
• Application Number:
  US08/552,675
• Time in Patent Office: 844 Days
• Field of Search: 250/573, 250/574, 250/576, 356/335, 356/336
• US Class Current: 250/573
• CPC Class Codes: G01N 15/0227 using imaging; using holography
• CPC Class Codes: G01N 15/147 the analysis being performed on a sample stream
• CPC Class Codes: G01N 2015/0294 Particle shape

Abstract

An apparatus for analyzing particle images includes a sheath flow cell for transforming a particle suspension flow into a flat flow surrounded by a sheath liquid, a light source for irradiating particles in the transformed particle suspension flow, a video camera for capturing particle images of irradiated particles, an image analyzer for analyzing the captured particle images, and a display device. The image analyzer including a calculator for measuring a projected area and perimeter of each captured particle image to calculate a particle diameter and circularity of each particle, a graph making device for making a histogram based on the particle diameter and for making a scattergram based on two parameters corresponding to the particle diameter and the circularity to allow the display device to display the histogram and the scattergram, a memory for storing each of the captured particle images, and a particle image recalling device for allowing the display device to collectively display the particle images stored by the memory.

Claims

1. An apparatus for analyzing particle images comprising:

a sheath flow cell for transforming a flow of particle suspension into a flow surrounded by a sheath liquid;

irradiating means for irradiating particles in the transformed particle suspension flow with a light;

image capturing means for capturing particle images of the irradiated particles;

image analyzing means for analyzing the captured particle images; and

a display,

the image analyzing means including;

calculating means for measuring a projected area of each captured particle image to calculate a particle diameter of each particle;

graph making means for making a histogram based on particle size frequency data corresponding to the particle diameters and for allowing the display to display the histogram;

storage means for storing each captured particle image; and

particle image recalling means for allowing the display means to collectively display the particle images stored by the storage means,

wherein the image capturing means further includes means for providing a plurality of capturing magnifications, wherein measuring ranges of particle diameters differ at each capturing magnification and partially overlap each other,

wherein the calculating means calculates particle size frequency data based on particle images captured at the plurality of capturing magnifications, corrects the particle size frequency data depending upon an amount of samples obtained at each capturing magnification, and integrates the particle size frequency data obtained at the plurality of capturing magnifications.

2. The apparatus according to claim 1, which further comprises at least one of supply means for selecting a sheath liquid from plural kinds of sheath liquid in accordance with a property of the particle suspension to supply the selected sheath liquid to the sheath flow cell and dyeing means for staining the particles in advance.

3. The apparatus according to claim 1, wherein the sheath flow cell transforms the particle suspension flow into a flat flow and the image capturing means captures images of the particles through a flat surface of the particle suspension flow.

4. The apparatus according to claim 1, wherein the calculating means and the graph making means ignore the particle images that are on an edge of a screen obtained by the image capturing means to obtain the particle size frequency data and correct the obtained frequency data according to the particle diameter.

5. The apparatus according to claim 1, wherein the calculating means further includes means for measuring a perimeter of each captured particle image to calculate a circularity of each particle and the graph making means further includes means for making a scattergram based on two parameters corresponding to the particle diameter and the circularity and for allowing the display to display the scattergram.

6. The apparatus according to claim 1, wherein the calculating means integrates, by weighted average method, the particle size frequency data obtained at the plurality of capturing magnifications.

7. A method for analyzing particle images comprising the steps of:

transforming a flow of particle suspension into a flow surrounded by a sheath liquid;

irradiating particles in the transformed particle suspension flow with a light;

capturing particle images of the irradiated particles, said capturing step including providing a plurality of capturing magnifications, wherein measuring ranges of particle diameters differ at each capturing magnification and partially overlap each other;

analyzing the captured particle images, including

measuring a projected area and perimeter of each captured particle image;

calculating a particle diameter of each particle in accordance with the measuring step, said calculating step including

determining particle size frequency data based on particle images captured at the plurality of capturing magnifications,

correcting the particle size frequency data depending upon an amount of samples obtained at each capturing magnification, and

integrating the particle size frequency data obtained at the plurality of capturing magnifications, and

making a histogram based on particle size frequency data corresponding to the particle diameters;

displaying the histogram and the scattergram;

storing each captured particle image; and

collectively displaying the particle images stored by the storing means, the collective displaying providing confirmation of morphology and aggregation of the irradiated particles.

8. The method according to claim 7, wherein the analyzing step further includes measuring a perimeter of each captured particle image to calculate a circularity of each particle and making a scattergram based on two parameter corresponding to the particle diameter and the circularity, and the displaying step further includes displaying the scattergram.

9. The method according to claim 8, wherein said analyzing step includes calculating, from the calculated circularity of each particle, at least one of circularity frequency data, an average of circularity, and a standard deviation of circularity to be displayed by the displaying step.

10. The method according to claim 7, wherein the integrating step includes integrating, by weighted average method, the particle size frequency data obtained at the plurality of capturing magnifications.

11. The method according to claim 7, further comprising

selecting a sheath liquid from plural kinds of sheath liquid in accordance with a property of the particle suspension;

supplying the selected sheath liquid to the sheath flow cell; and

staining the particles in advance.

12. The method according to claim 7, wherein said transforming step includes transforming the particle suspension flow into a flat flow and the capturing step includes capturing images of the particles through a flat surface of the particle suspension flow.

13. The method according to claim 12, wherein the calculating step further includes:

calculating particle size frequency data based on particle images capture at the plurality of capturing magnifications,

correcting the particle size frequency data depending upon an amount of samples obtained at each capturing magnification, and

smoothly integrating, by a weighted average method, the particle size frequency data obtained at the plurality of capturing magnifications.

14. The method according to claim 7, wherein the calculating step and the making steps each further include ignoring the particle images that are on an edge of a screen obtained by the capturing step to obtain the particle size frequency data and correcting the obtained frequency data according to the particle diameter.

15. The method according to claim 7, wherein the capturing step further includes providing a plurality of capturing magnifications, wherein measuring ranges of particle diameters differ at each capturing magnification and partially overlap each other.

16. The method according to claim 7, wherein the analyzing step further includes:

inputting information as to whether each of the collectively displayed particle images represents a single particle or an aggregation of a plurality of particles;

calculating a numerical proportion of the single particles to the aggregations based on the input information; and

outputting the calculated proportion.

17. The method according to claim 7, wherein the analyzing step further includes inputting information as to whether each of the collectively displayed particle images represents a single particle or an aggregation of a plurality of particles, and the calculating step further includes calculating the particle diameter and circularity of the particle based only on the images of the single particles differentiated by the input information.

18. An apparatus for analyzing particle images comprising:

a sheath flow cell for transforming a flow of particle suspension into a flow surrounded by a sheath liquid;

irradiating means for irradiating particles in the transformed particle suspension flow with a light;

image capturing means for capturing particle images of the irradiated particles;

image analyzing means for analyzing the captured particle images, the image analyzing means including;

means for providing a plurality of capturing magnifications, wherein measuring ranges of particle diameters differ at each capturing magnification and partially overlap each other, and

calculating means for calculating particle size frequency data based on particle images captured at the plurality of capturing magnifications, correcting the particle size frequency data depending upon an amount of samples obtained at each capturing magnification, and integrating the particle size frequency data obtained at the plurality of capturing magnifications.

19. The apparatus according to claim 18, wherein the calculating means integrates, by a weighted average method, the particle size frequency data obtained at the plurality of capturing magnifications.

20. An apparatus for analyzing particle images comprising:

a sheath flow cell for transforming a flow of particle suspension into a flow surrounded by a sheath liquid;

irradiating means for irradiating particles in the transformed particle suspension flow with a light;

image capturing means for capturing particle images of the irradiated particles;

image analyzing means for analyzing the captured particle images, the image analyzing means including;

storage means for storing each captured particle image,

particle image recalling means for allowing a display to collectively display the particle images stored by the storage means,

input means for inputting information as to whether each of the collectively displayed particle images represents a single particle or an aggregation of a plurality of particles,

means for calculating a numerical proportion of the single particles to the aggregations based on the input information, and

means for outputting the calculated proportion.

21. The apparatus according to claim 20, wherein the image analyzing means further includes operating means for calculating, from the calculated circularity of each particle, at least one of circularity frequency data, an average of circularity, and a standard deviation of circularity to be displayed by the display.

22. The apparatus according to claim 20, wherein the image analyzing means further includes input means for inputting information as to whether each of the collectively displayed particle images represents a single particle or an aggregation of a plurality of particles, and means for calculating a numerical proportion of the single particles to the aggregations based on the input information to allow the display means to display the calculated proportion.

23. The apparatus according to claim 20, wherein the image analyzing means further includes input means for inputting information as to whether each of the collectively displayed particle images represents a single particle or an aggregation of a plurality of particles, and the calculating means calculates the particle diameter and circularity of the particle based only on the images of the single particles differentiated by the input information.

24. An apparatus for analyzing particle images comprising:

a sheath flow cell for transforming a flow of particle suspension into a flow surrounded by a sheath liquid;

irradiating means for irradiating particles in the transformed particle suspension flow with a light;

image capturing means for capturing particle images of the irradiated particles;

image analyzing means for analyzing the captured particle images, the image analyzing means including;

storage means for storing each captured particle image,

particle image recalling means for allowing a display to collectively display the particle images stored by the storage means,

input means for inputting information as to whether each of the collectively displayed particle images represents a single particle or an aggregation of a plurality of particles, and

calculating means for calculating the particle diameter and circularity of the particle based only on the images of the single particles differentiated by the input information.