JPH0560541B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is used for flow cytometers, etc.
The present invention relates to a particle analysis device that can specify the shape of an irradiation beam and perform measurements with high precision when scanning the irradiation beam.

[Prior art] A flow cytometer is a device that elucidates the properties and structure of cells by irradiating a rapidly flowing cell suspension solution, that is, a sample solution, with laser light, for example, and detecting photoelectric signals from the scattered light and fluorescence. It is used in fields such as cytochemistry, immunology, hematology, oncology, and genetics.

In conventional particle analysis devices used in flow cytometers and the like, test particles such as blood cells are passed through a flow section in the center of the flow cell that has a minute rectangular cross section of, for example, 200 μm x 200 μm, while being wrapped in a sheath fluid. It is possible to obtain particle properties such as the shape, size, and refractive index of the target particle by irradiating it with irradiation light such as a laser beam and using the resulting forward and side scattered light. In addition, for test particles that can be stained with fluorescent agents, important information for analyzing the test particles can be obtained by detecting the fluorescence of the test particles from side scattering light in a direction almost perpendicular to the irradiation light. can be found.

Conventionally, the particles to be examined are passed through a fixed light beam, but since the irradiation beam is usually a laser beam and has a Gaussian intensity distribution, it is difficult to detect the movement of the sample flow or the Due to variations in the flow position of the test particles, the test particles do not necessarily pass through the peak position of the Gaussian intensity distribution, and the energy irradiated to each test particle is different, causing variations in measurement values. There is a point.

[Objective of the Invention] An object of the present invention is to scan the irradiation light in order to eliminate the drawbacks of the conventional example described above, and even if there are variations in the position of the particles to be inspected in the flow in the scanning direction, the same light can be used. An object of the present invention is to provide a particle analysis device that can impart intensity to particles to be examined.

[Summary of the invention] The gist of the present invention for achieving the above object is as follows:
In a device that measures test particles by irradiating light from a light source onto test particles in a fluid and detecting the light generated by a light receiving element, a second direction intersecting the first direction in which the test particles flow; A light scanning means for scanning light from the light source in a direction, and a shape setting means for setting the shape of the scanning light by the light scanning means to be longer in the first direction than in the second direction. This is a particle analysis device.

[Embodiments of the Invention] The present invention will be described in detail based on illustrated embodiments.

Fig. 1a is a configuration diagram of the embodiment as seen from the plane direction;
b is an optical path diagram inside the flow cell viewed from the side. A laser light source 2 is disposed in a direction perpendicular to the flow path 1a through which the sample flow containing the particles S to be detected in the flow cell 1 passes, and the laser light emitted from the laser light source 2 is transmitted to an A/O light deflector 3 and a cylindrical lens. The light is focused on the flow cell 1 via the light beams 4 and 5. The cylindrical lens 4 has refractive power only in the flow direction of the sample flow, and the cylindrical lens 5 has a focal point at the center of the A/O optical deflector 3 in a plane orthogonal to the flow of the sample flow. has been done. Further, on the opposite side of the flow cell 1, a stopper 6, a condensing lens 7, and a photodetector 8 are arranged.

The laser light emitted from the laser light source 2 is A/
While being scanned by the O light deflector 3, the flow section 1a of the flow cell 1 is
The light is focused inside. Then, the scattered light from the test particles S is focused on the photodetector 8 by the condensing lens 7 and detected. Note that the stopper 6 functions to cut off the direct light at this time. Also, A/O
By placing the vicinity of the center of the optical deflector 3 at the focal position in front of the cylindrical lens 5, it is possible to scan and irradiate the target particle S with the laser beam in a telecentric state in the X direction. Particle detection S
will always be irradiated with a constant amount of light.

In FIGS. 1a and 1b, cylindrical lenses 4 and 5
Because the F value of the light beam that hits the particle S to be examined differs due to the effect of , the shape of the imaging beam L becomes elliptical as shown in FIG. 2. Also, in Figure 2, A, B
is the intensity distribution at the center cross section of each imaging beam L.

FIG. 3 is a diagram showing the relationship between the particles S to be detected flowing through the flow section 1a and the shape of the scanning beam. FIG. 3a corresponds to a case where a stationary particle S to be inspected is scanned, or a case where the scanning intensity is high relative to the velocity in the flow direction Y. On the other hand, Fig. 3b shows t1, t2, t3
As time passes, the position of the light beam in the flow direction Y changes.

Therefore, if the shape of the imaging beam L is made long in the flow direction Y of the sample flow as shown in FIG.
Since there is little change in the light intensity in the flow direction Y as shown in B, there is little change in the energy distribution hitting the test particles S. In this way, by making the shape of the imaging beam L elliptical, even if the flow of the particle S to be detected is fast, the light energy of approximately the same intensity in the direction of flow is applied to the particle S to be inspected during one scan. is irradiated to enable highly accurate measurements.

It goes without saying that the shape of the imaging beam L may not be a regular ellipse but may be substantially elliptical.

[Effects of the Invention] As explained above, the particle analysis device according to the present invention can detect particles to be detected with high accuracy by making the shape of the scanning imaging beam into a substantially elliptical shape having a major axis in the flow direction of the sample flow. can be analyzed.

[Brief explanation of the drawing]

The drawings show an embodiment of the particle analysis device according to the present invention, and Fig. 1 a shows its configuration, b shows an optical path diagram seen from a direction perpendicular to a, and Fig. 2 shows the shape and intensity of the imaging beam. The relationship diagrams of distribution, FIGS. 3a and 3b, are explanatory diagrams of the relationship between the shape of the imaging beam and the particles to be examined. 1 is a flow cell, 1a is a flow path, 2 is a laser light source, 3 is a light deflector, 4 and 5 are cylindrical lenses, 6 is a stopper, 7 is a condensing lens, and 8 is a photodetector.

Claims (1)

[Scope of Claims] 1. In an apparatus that measures test particles by irradiating light from a light source onto test particles in a fluid and detecting the light generated by a light-receiving element, A light scanning means for scanning light from the light source in a second direction intersecting one direction, and shape setting of the scanning light by the light scanning means so that the first direction is longer than the second direction. A particle analysis device comprising: means. 2. The particle analysis device according to claim 1, wherein the shape setting means includes a cylindrical lens, and the scanning light has an elliptical shape. 3. The particle analysis device according to claim 1, wherein the optical scanning means includes an A/O optical deflector. 4. The particle analysis apparatus according to claim 1, wherein the optical scanning means is a telecentric optical system.