Circular polarization illumination based analyzer system

• US 7,630,075 B2
• Filed: 10/31/2006
• Issued: 12/08/2009
• Est. Priority Date: 09/27/2004
• Status: Active Grant

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Fritz, Bernard S.
• Primary Examiner(s): NGUYEN, SANG H
• Application Number:
  US11/554,878
• Publication Number:
  US 20070058252A1
• Time in Patent Office: 1,134 Days
• Field of Search: 356335-343, 356364-369, 356317-319, 250/458.1, 250/459.1, 250/461.1, 250/461.2
• US Class Current: 356/337
• CPC Class Codes: G01N 15/1404 Handling flow, e.g. hydrodynamic focusing
• CPC Class Codes: G01N 15/1459 the analysis being performed on a sample stream
• CPC Class Codes: G01N 2015/016 White blood cells
• CPC Class Codes: G01N 2015/1027 Determining speed or velocity of a particle
• CPC Class Codes: G01N 2015/1413 Hydrodynamic focussing
• CPC Class Codes: G01N 2015/1477 Multiparameters
• CPC Class Codes: G01N 2015/1486 Counting the particles
• CPC Class Codes: G01N 2015/1493 Particle size
• CPC Class Codes: G01N 2021/4707 Forward scatter; Low angle scatter
• CPC Class Codes: G01N 2021/4792 Polarisation of scatter light
• CPC Class Codes: G01N 21/21 Polarisation-affecting properties G01N21/19 takes precedence

Abstract

A particle discriminator using circularly polarized light projected through a channel having target particles. Light may be propagated through the channel, with some light scattered separated into forward angle scattered light, small angle scattered light and unscattered light. The forward angle scattered light may be linearly polarized and detected. The small angle scattered light may be linearly polarized in a direction orthogonal to the direction of the polarization of the forward angle scattered light, and at least both these kinds of light may be detected. Data from these detected kinds of light may be analyzed to discriminate particles from one another.

Claims

1. A polarization based analyzer system comprising:

a light source;

a first polarizer situated at an output of the light source;

a channel;

a first optical mechanism for focusing light from the polarizer to the channel;

a second optical mechanism for collimating light from the channel;

a structure for directing a first light from the second optical mechanism in a first direction and a second light from the second optical mechanism in a second direction;

a first detector for detecting the first light;

a second detector for detecting second light;

a second polarizer situated between the structure and the first detector; and

a third polarizer situated between the structure and the second detector.

2. The system of claim 1, wherein:

the light source is for emanating linearly polarized light;

the first polarizer is a circular polarizer;

the second polarizer is a first linear polarizer; and

the third polarizer is a second linear polarizer.

3. The system of claim 2, wherein a polarization state of the second linear polarizer is approximately orthogonal to a polarization state of the second linear polarizer.

4. The system of claim 3, wherein:

the first light comprises forward angle scattered light; and

the second light comprises small angle scattered light.

5. The system of claim 4, further comprising:

a computer connected to the first and second detectors; and

wherein;

the forward angle scattered light is some of the first light scattered by particles in the channel;

the small angle scattered light is some of the second light scattered by particles in the channel;

the computer processes data from the first and second detectors into small angle scatter light versus forward angle scatter light graphs; and

the graphs provide groupings of the particles according to at least one feature that distinguish particles from one another.

6. The system of claim 4, wherein:

the structure comprises a first portion, a second portion and a third portion;

wherein;

the first portion is transmissive;

the second portion is reflective; and

the third portion is reflective;

the first portion is for transmitting the first light; and

the second portion is for reflecting the second light; and

the third portion is for reflecting a third light in a third direction.

7. The system of claim 1, wherein the channel is of a cytometer.

8. A method for discriminating particles, comprising:

projecting circularly polarized light through a receptacle for particles;

collimating the light that has been projected through the receptacle;

separating the light into small angle scattered light and forward angle scattered light;

linearly polarizing the forward angle scattered light;

linearly polarizing the small angle scattered light orthogonally relative to the polarized forward angle scattered light; and

analyzing the polarized forward angle scattered light and the polarized small angle scattered light to discriminate particles that being in the receptacle.

9. The method of claim 8, further comprising:

converting the polarized forward angle scattered light into a first type of electronic signals;

converting the polarized small angle scattered light into a second type of electronic signals; and

processing the first and second types of electronic signals into data representing various particles that being in the receptacle.

10. The method of claim 8, wherein the receptacle is a flow channel of a cytometer.

11. A circularly polarized illumination-based analyzer comprising:

a circularly polarized light source;

a first light splitter;

a channel situated between the light source and the first light splitter; and

a first linear polarizer proximate to the light splitter;

a second linear polarizer proximate to the first light splitter and having a polarization direction approximately orthogonal to a polarization direction of the first linear polarizer;

a first detector proximate to the first linear polarizer;

a second detector proximate to the second linear polarizer;

the first light splitter for separating light from the channel into small angle scattered light, forward angle scattered light, and unscattered light;

the first linear polarizer for polarizing forward angle scattered light; and

the second linear polarizer is for polarizing small angle scattered light.

12. The analyzer of claim 11, further comprising:

a third detector proximate to the channel; and

wherein the third detector is for detecting unscattered light.

13. The analyzer of claim 11, further comprising:

a second light splitter situated between the first light splitter and the first polarizer;

a third detector proximate to the second light splitter;

a third linear polarizer situated between the second light splitter and the third detector;

a third light splitter situated between the first light splitter and the second linear polarizer;

a fourth detector proximate to the third light splitter; and

a fourth linear polarizer situated between the third light splitter and the fourth detector; and

wherein;

the third linear polarizer is orthogonal relative to the first linear polarizer; and

the fourth linear polarizer is orthogonal relative to the second linear polarizer.

14. A polarization based analyzer system comprising:

a light source;

a first polarizer situated at an output of the light source;

a channel;

a first optical mechanism for focusing light from the polarizer to the channel;

a second optical mechanism for collimating light from the channel;

a structure for directing a first light from the second optical mechanism in a first direction and a second light from the second optical mechanism in a second direction;

a first detector for detecting the first light;

a second detector for detecting second light;

a second polarizer situated between the structure and the first detector; and

a third polarizer situated between the structure and the second detector; and

wherein;

the light source is for emanating linearly polarized light;

the first polarizer is a circular polarizer;

the second polarizer is a first linear polarizer;

the third polarizer is a second linear polarizer;

a polarization state of the second linear polarizer is approximately orthogonal to a polarization state of the second linear polarizer;

the first light comprises forward angle scattered light;

the second light comprises small angle scattered light;

the structure comprises a first portion, a second portion and a third portion;

the first portion is transmissive;

the second portion is reflective;

the third portion is reflective;

the first portion is for transmitting the first light;

the second portion is for reflecting the second light; and

the third portion is for reflecting a third light in a third direction.

15. The system of claim 14, further comprising:

a third detector for detecting the third light; and

wherein the third light is unscattered light.

16. The system of claim 14, wherein:

the second portion is a ring-like band having borders that are different sized concentric circles;

the first portion is situated within the smaller concentric circle; and

the third portion is situated within the first portion.

17. A polarization based analyzer system comprising:

a light source;

a first polarizer situated at an output of the light source;

a channel;

a first optical mechanism for focusing light from the polarizer to the channel;

a second optical mechanism for collimating light from the channel;

a structure for directing a first light from the second optical mechanism in a first direction and a second light from the second optical mechanism in a second direction;

a first detector for detecting the first light;

a second detector for detecting second light;

a second polarizer situated between the structure and the first detector; and

a third polarizer situated between the structure and the second detector; and

wherein the channel is of a cytometer.

18. A method for discriminating particles, comprising:

projecting circularly polarized light through a receptacle for particles;

collimating the light that has been projected through the receptacle;

separating the light into small angle scattered light and forward angle scattered light;

linearly polarizing the forward angle scattered light;

linearly polarizing the small angle scattered light orthogonally relative to the polarized forward angle scattered light;

analyzing the polarized forward angle scattered light and the polarized small angle scattered light to discriminate particles that being in the receptacle;

converting the polarized forward angle scattered light into a first type of electronic signals;

converting the polarized small angle scattered light into a second type of electronic signals; and

processing the first and second types of electronic signals into data representing various particles that being in the receptacle.

19. The method of claim 18, further comprising:

plotting the data representing the signals into plots; and

analyzing the plots to classify the particles into several groups.

20. A method for discriminating particles, comprising:

projecting circularly polarized light through a receptacle for particles;

collimating the light that has been projected through the receptacle;

separating the light into small angle scattered light and forward angle scattered light;

linearly polarizing the forward angle scattered light;

linearly polarizing the small angle scattered light orthogonally relative to the polarized forward angle scattered light; and

analyzing the polarized forward angle scattered light and the polarized small angle scattered light to discriminate particles that being in the receptacle; and

wherein the receptacle is a flow channel of a cytometer.

21. A circularly polarized illumination-based analyzer comprising:

a circularly polarized light source;

a first light splitter;

a channel situated between the light source and the first light splitter; and

a first linear polarizer proximate to the light splitter;

a second linear polarizer proximate to the first light splitter and having a polarization direction approximately orthogonal to a polarization direction of the first linear polarizer;

a first detector proximate to the first linear polarizer; and

a second detector proximate to the second linear polarizer; and

wherein;

the first light splitter is for separating light from the channel into small angle scattered light, forward angle scattered light, and unscattered light;

the first linear polarizer is for polarizing forward angle scattered light; and

the second linear polarizer is for polarizing small angle scattered light; and

further comprising;

a second light splitter situated between the first light splitter and the first polarizer;

a third detector proximate to the second light splitter;

a third linear polarizer situated between the second light splitter and the third detector;

a third light splitter situated between the first light splitter and the second linear polarizer;

a fourth detector proximate to the third light splitter; and

a fourth linear polarizer situated between the third light splitter and the fourth detector; and

wherein;

the third linear polarizer is orthogonal relative to the first linear polarizer; and

the fourth linear polarizer is orthogonal relative to the second linear polarizer.

22. The analyzer of claim 21, further comprising:

a fifth detector proximate to the first light splitter;

a fifth linear polarizer situated between the fifth detector and the first light splitter;

a fourth light splitter situated between the fifth linear polarizer and the first detector;

a sixth detector proximate to the fourth light splitter; and

a sixth linear polarizer situated between the sixth detector and the fourth light splitter; and

wherein;

the fifth detector is for detecting unscattered light;

the sixth detector is for detecting unscattered light; and

the sixth linear polarizer is orthogonal relative to the fifth linear polarizer.

23. The analyzer of claim 22, further comprising:

a processor connected to the first, second, third, fourth, fifth and sixth detectors; and

the processor processes signals from the first, second, third, fourth, fifth and sixth detectors into data for discriminating particles in the channel.