JPH03235037A - Particle analyzing apparatus - Google Patents

Abstract

PURPOSE:To obtain a compact and inexpensive particle analyzing apparatus in a simple structure by receiving the obtained light by use of a photodetector through a photometric optical system having an optical member with at least one aspherical surface. CONSTITUTION:A laser beam from a laser source 2 irradiates a particle to be detected which passes a circulating part 1a of a flow cell 1, through a cylindrical lens 3 and a lens 4. The front scattering light is condensed by an aspherical lens 12 and received by a photodetector 7 via a field stop 6. The side scattering light and fluorescence are condensed by an aspherical lens 13 and received by a photodetector 10 via a condenser lens 8 and a field stop 9. The front scattering light or the side scattering light, fluorescense is correctly formed into an image at the position of the field stop 6 or 9. Accordingly, if the lenses 12, 13 are processed to be an ideal shape, the number of lenses of the condenser lens 8 can be reduced. An efficient photometric optical system can be formed of a small number of lenses, so that the particle analyzing apparatus becomes compact and inexpensive.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention, for example in a flow cytometer, irradiates test particles passing through a flow cell with a laser beam or the like, and detects scattered light from the test particles, The present invention relates to a particle analysis device that measures depolarized light, fluorescence, and the like to analyze the properties, structure, etc. of test particles.

[Conventional technology] A flow cytometer is a cell suspension solution that flows at high speed.
In other words, it is a device that irradiates a sample liquid with, for example, a laser beam, detects a photoelectric signal from the scattered light and fluorescence, and elucidates the properties and structure of cells, and is used in cytochemistry, immunology, hematology, oncology, genetics, etc. used in the field of

In the conventional particle analysis device used in this flow cytometer, etc., the central part of the flow cell is 200 tLmx.
Inside the flow part with a minute rectangular cross section of 200 LLm,
Laser light or other light is irradiated onto test particles such as blood cells that pass through the sheath fluid, and the resulting forward and side scattered light is used to determine the shape, size, and shape of the test particles.
It is possible to obtain particle-like properties such as refractive index. Also,
For test particles that can be stained with a fluorescent agent, important information for analyzing the test particles is obtained by detecting the fluorescence of the test particles from side scattered light in a direction almost perpendicular to the irradiation light. be able to.

FIG. 3 is a diagram showing the configuration of a conventional particle analysis device.
is a flow cell having a flow section 1a through which a sample liquid containing test particles flows at high speed together with a sheath liquid. flow cell l
A laser light source 2 is provided toward the flow cell 1, and a cylindrical lens 3.4 is arranged from the laser light source 2 side on the optical axis O1 between the flow cell 1 and the flow cell 1. As a forward scattered light photometric optical system, a condenser lens 5, a field stop 6, and a photodetector 7 are arranged on the optical axis 01 on the opposite side of the flow cell l, and as a side scattered light and fluorescence photometric optical system. A condensing lens 8 is disposed on the optical axis 02 in a direction perpendicular to the flow section 1a and the optical axis 01.
, a field stop 9, and a photodetector 10 are arranged.

When the laser beam L1 is emitted from the laser light source 2 while the sample liquid wrapped in the high-speed laminar flow sheath liquid passes through the flow section 1a inside the flow cell 1, the laser beam L1 advances along the optical axis and forms a cylindrical lens 3.4
The light is focused by the ellipsoidal spot and irradiates the test particles in the flow section la with an elliptical spot.

The forward scattered light from the test particles is received by the photodetector 7 via the condenser lens 5 and the field stop 6, and information regarding the size of the test particles can be obtained from the amount of the received light. On the other hand, side scattered light and fluorescence are condensed by a condenser lens 8, and a field aperture 9
The light is received by the photodetector 10 via the light beam, and information mainly regarding the shape of the particle to be detected can be obtained from the amount of light received. Here, since scattered light and especially fluorescence are weak, it is generally a good idea to incorporate an objective lens for a microscope into the condenser lenses 5 and 8 to increase the numerical aperture of the photometric optical system. being done.

[Problems to be Solved by the Invention] However, in the conventional example, as mentioned above, for example, an objective lens for a microscope is used, but in order to increase the numerical aperture, the lens of the photometric optical system must be made large. In addition, due to the large numerical aperture, the photometric optical system uses many lenses for aberration correction, and in order to achromatize the lenses, various types of glass materials that are expensive and difficult to process are used. The analysis device becomes complicated, large and expensive.

An object of the present invention is to provide a particle analysis device that is simple, compact, and inexpensive by using an aspherical lens.

[Means for Solving the Problems] In order to achieve the above-mentioned object, the particle analysis device according to the present invention irradiates test particles in a liquid passing through a flow section made of a transparent body with irradiation light, A particle analysis device that receives the obtained light with a photodetector via a photometric optical system and analyzes a target particle based on the amount of light received by the photodetector, the photometric optical system having at least one aspherical surface. It is characterized by having an optical member arranged therein.

[Operation] The particle analysis device having the above configuration irradiates the test particles in the liquid passing through the flow section with irradiation light, and transmits the obtained light through a photometric optical system having an optical member having an aspherical surface on at least one surface. The light is received by a photodetector.

[Example] The present invention will be explained in detail based on the example illustrated in FIGS. 1 and 2. Note that the same reference numerals as in FIG. 3 indicate the same members.

FIG. 1 is a configuration diagram of a particle analyzer. A stopper 11 and an aspherical lens 12 having aspherical surfaces on both sides are arranged between a flow cell 1 and a field stop 6 on the optical axis 01. An aspherical lens 13 having aspherical surfaces on both sides and a condensing lens 8 are arranged between the flow cell 1 and the field stop 9.

The laser beam L1 from the laser light source 2 irradiates the test particles passing through the flow section 1a of the flow cell 1 via the cylindrical lens 3 and lens 4 as in the conventional example, and the forward scattered light is emitted by the aspherical lens 12. The light is condensed and further received by a photodetector 7 via a field diaphragm 6. Further, the side scattered light and fluorescence are collected by an aspherical lens 13 and received by a photodetector 10 via a condensing lens 8 and a field stop 9.

The aspherical lens 12.12 is manufactured by molding, and the aspherical lens 12 has a numerical aperture N/'; 13 is combined with a condensing lens 8 to effectively correct aberrations of side scattered light and fluorescence with numerical aperture NA≦0.7, and forward scattered light, side scattered light, and fluorescence are The image is accurately formed at the position of the diaphragm 6 or field diaphragm 9.

In the conventional example, a large number of lenses are incorporated into the condenser lens 5.8 for aberration correction and achromatization, but the aspherical lens 12, - aspherical lens processed into an ideal shape in this way. 13, the number of condensing lenses 5.8 can be reduced, a photometric optical system with good performance can be constructed with a small number of lenses, and a compact and low-cost particle analysis device can be realized. The background to this is that recent molding technology in particular has made it possible to produce high-precision aspherical lenses that meet the requirements at low cost. The reason why the upper limit of the numerical aperture NA that can be corrected by the aspherical lens 13 is set larger than that of the aspherical lens 12 is because side scattered light and fluorescence are weaker than forward scattered light, and This is because a photometric optical system with a numerical aperture NA is required.

In a microscope, etc., if the refractive index of the medium between the objective lens and the object to be examined is n, and the maximum angle that the light beam incident on the objective lens makes with the optical axis is α, then the numerical aperture NA is calculated using the following formula. Since the refractive index is approximately 1, a so-called immersion objective lens in which the space between the object to be examined and the objective lens is filled with a medium with a refractive index of 1 or more, such as chrycerin or seda oil, has a higher refractive index than an objective lens in air. Numerical aperture increases.

FIG. 2 is a block diagram of a particle analysis device according to a second embodiment applying this principle, and shows the aspherical lens 1 of the first embodiment.
2 or instead of the aspherical lens 13, an aspherical lens 14 and an aspherical lens 15, each having a flat surface on the flow cell 1 side and an aspherical surface on the opposite surface, are fixed to the side surface of the flow cell 1 on the optical axes 01 and 02. has been done. Since the aspherical lenses 13 and 14 can be regarded as immersion lenses using the flow cell 1 as a medium,
If the flow cell 1 is formed of quartz glass with a refractive index of 1 or more, for example, 1.46, aberrations can be corrected and achromatized as in the first embodiment, and furthermore, the numerical aperture NA can be larger than 1. A photometric optical system is easily realized. Note that even if the aspherical lens 13.14 is not directly fixed to the flow cell 1, the same effect can be obtained even if the space between the aspherical lens 13.14 and the flow cell 1 is filled with a medium having a refractive index of 1 or more.

[Effects of the Invention] As explained above, the particle analysis device according to the present invention receives the obtained light through a photometric optical system having an optical member with at least one aspherical surface, and receives the obtained light on a photodetector. When used, aberration correction and achromatization are performed well even with a large numerical aperture, so the photometric optical system can be easily constructed, and is small and inexpensive.

[Brief explanation of drawings]

Drawings 1 and 2 show an embodiment of a particle analysis device according to the present invention, FIG. 1 is a block diagram of the first embodiment, and FIG. 2 is a block diagram of the second embodiment. FIG. 3 is a block diagram of a conventional particle analysis device. 1 is a flow cell, 1a is a flow section, 5.8 is a condensing lens, 6.9 is a field stop, 7.10 is a photodetector, 12.1
3.14.15 is an aspherical lens.

Claims (1)

[Claims] 1. Irradiation light is irradiated onto test particles in a liquid passing through a flow section made of a transparent body, the resulting light is received by a photodetector via a photometric optical system, and the light is detected. What is claimed is: 1. A particle analysis device for analyzing test particles based on the amount of light received by a device, characterized in that an optical member having at least one aspherical surface is disposed within the photometric optical system. 2. The particle analysis device according to claim 1, wherein the flow cell having the flow section is a transparent body having a refractive index of 1 or more, and the aspherical optical member is adhered to the flow section. 3. The particle analysis device according to claim 1, wherein a space between the flow cell having the flow section and the aspherical optical member is filled with a medium having a refractive index of 1 or more.