JPS6135335A - Particle analyzing device - Google Patents

Abstract

PURPOSE:To obtain a stable measured value with high accuracy by measuring sideway scattered light in plural directions across a sample, and averaging measured values and generating an output signal. CONSTITUTION:A lens 10a, photodetector 11a, lens 10b, and photoelectric detector 11b are installed in two directions perpendicular to incident luminous flux so as to measure sideway scattered light projected to both short sides of a flowing part 2. Then, outputs of photoelectric detectors 11a and 11b are connected to an arithmetic part 12, storage part 13, and display part 14. Namely, scattered light La in one direction of the sideway scattered light from the sample and scattered light Lb in the opposite direction are passed through the lenses 10a and 10b and converted by the detectors 11a and 11b into light signal outputs, which are inputted to the arithmetic part 12; and the result is inputted to the storage part 13 and displayed on the display part 14. Therefore, the even if the flow of sample in the flowing part 2 deviates lengthwise, scattered light from both sides of the a moving direction is detected and processed, so the influence of the movement of the sample is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a particle analysis device used in a flow cytometer or the like, which irradiates a sample with light, measures the side scattered light from multiple directions, and averages the measured values. be.

A flow cytometer is a device that irradiates a rapidly flowing cell suspension solution with, for example, a laser beam, detects a photoelectric signal from the scattered light, and elucidates the nature and structure of cells. It is being used in fields such as , oncology, and genetics.

In conventional optical systems for particle analysis, side scattered light emitted when a sample is irradiated with light is measured from one direction. That is,
For example, 70 pmX in the center of the flow cell l shown in FIG.
Inside the flow section 2 having a minute rectangular cross section of 20 ILm,
Samples S, such as blood cells, pass through wrapped in sheath fluid,
As shown in FIG. 2, parallel light from a laser light source (not shown) is focused through a lens 3, and forward scattered light in the straight direction of this irradiated light is received on a photoelectric detector 5 through a lens 4. Information on the size of the specimen S is obtained. In addition, the side scattered light obtained in a direction almost perpendicular to the straight direction of the irradiated light is
It is detected by the lens 6 and the photoelectric detector 7, and information on the internal state of the specimen S can be obtained. Furthermore, when performing cytochemical analysis by fluorescently labeling cells, measurement can be performed using a combination of a barrier filter, lens 6, and photoelectric detector 7 (not shown).

The photoelectric detector 5 on the forward scattered light side can be sufficiently detected by a semiconductor detector having a normal detection ability, but since the side scattered light is extremely weak compared to the forward scattered light, a photoelectric detector 5 is used. 7 etc., a light intensifier tube such as a photomultiplier is used. Further, in order to obtain a large amount of received side scattered light, it is conceivable to increase the output of the light source, but for example, in the case of a laser light source, the output is required to be several watts. On the other hand, in order to reduce the light source output, it is desirable to increase the ability to collect side scattered light, but this can usually be achieved by increasing the numerical aperture of the focusing optical system. However, when the numerical aperture of the condensing optical system is increased in this manner, there is a problem in that when the distribution of the specimen S moves in the direction of the optical axis of the lens 6 within the flow section 2, variations in the amount of measured light tend to occur.

FIG. 3 shows how an image is formed when sample particles move on the measurement optical axis. In Fig. 3, when the light emitted by the particle at position 0 is guided to the photoelectric detector 7 through the condenser lens 6, the intensity of the optical signal is increased by the solid angle 2π (1-c
osφ1). Similarly, the light emitted by a particle at position 0' is proportional to the solid angle 2π (1-cosφ2). Therefore, if a particle moves from O to O'' on the measurement optical axis, the output signal of the photoelectric detector 7 will fluctuate even though the same particle is being measured, making the measurement inaccurate. This effect becomes particularly large as the solid angle φ becomes larger, that is, as the numerical aperture of the condensing lens 6 becomes larger.In this way, in the conventional particle analysis optical system, side scattered light If the numerical aperture of the condensing optical system is increased in order to obtain a large amount of received light, there is a drawback that variations in the amount of measured light are likely to occur due to movement of the specimen S in the optical axis direction.

The purpose of the present invention is to eliminate such drawbacks of conventional optical systems for particle analysis, measure side scattered light of a specimen from multiple lateral directions, and perform calculation processing on the multiple outputs obtained.
The purpose is to provide a particle analyzer that corrects variations in the amount of measurement light due to lateral movement of the sample and can perform stable and accurate measurements. a plurality of optical systems each having a photoelectric detector for measuring scattered light of the sample in both directions substantially orthogonal to a traveling direction of light irradiated onto the sample from a light source; The present invention is characterized by comprising an arithmetic processing circuit section for calculating an output signal from the detector.

The present invention will be explained in detail based on the embodiment shown in FIGS. 4 and 5. FIG.

Here, FIG. 4 is a block diagram of the optical system, and FIG. 5 is a block circuit diagram of the signal processing system. Note that the same reference numerals as in FIG. 2 represent the same members.

A lens 3 for condensing parallel light from a laser light source (not shown) onto the specimen S is disposed on the long side side of the flow section 2 of the flow cell 1, and is used to photometer forward scattered light in the incident direction of the irradiation light. The arrangement of the lens 4 and the photoelectric detector 5 is the same as in the conventional example shown in FIG.

Here, in order to measure side scattered light emitted to both short sides of the circulation section 2, a lens 10a and a photodetector 11b are installed in both directions substantially orthogonal to the above-mentioned incident light flux.
, a lens 10a, and a photoelectric detector 11b are installed.

Then, as shown in FIG. 5, photoelectric detectors 11a and llb
The output of is connected to the calculation section 12, the storage section 13, and the display section 14. That is, the scattered light La of the side scattered light from the specimen S and the scattered light Lb of the side scattered light in the opposite direction are transmitted to the photoelectric detectors 11a and llb via lenses loa and 10b, respectively.
The signal is converted into an optical signal output and input to the arithmetic unit 12.

The result calculated by this calculation unit 12 is stored in a storage unit 13.
, and is further displayed on the display unit 14.

For example, 1/2 of the sum of the outputs of the photoelectric detectors 11a and llb
is stored moment by moment in the storage unit 13 as data of the specimen S, and is finally displayed on a display unit 14 such as a CRT as histogram data.

By doing this, even if the flow of the sample S in the flow section 2 deviates along the long side direction of the flow section 2, the scattered light is detected and processed from both sides of the movement direction. , sample S
The impact of migration will be mitigated.

Further, the calculation in the calculation unit 12 is carried out by the photoelectric detectors 11a and l.
It is most common to simply average the sum of the outputs of lb, but it is also possible to simply calculate the sum, or
It is also conceivable to consider the distribution function in the long side direction of , and use other statistical processing methods such as the root mean square.

Furthermore, when the specimen S is fluorescently labeled, barrier filters may be inserted into the two side scattered light detection optical systems.

As explained above, the particle analyzer according to the present invention measures side scattered light in multiple directions across the sample, averages the values, and uses the resulting output signal to obtain highly accurate and stable measured values. It will be done. Further, even if the output of the light source is reduced, it is possible to obtain accuracy equivalent to that of the conventional method.

[Brief explanation of drawings]

Figure 1 is a perspective view of the flow cell, Figure 2 is a configuration diagram of the optical system of a conventional device, Figure 3 is an explanatory diagram of the light collection efficiency of the lens, and Figure 4
The figure below shows an example of a particle analysis device according to the present invention,
FIG. 4 is a diagram of its optical configuration, and FIG. 5 is a block circuit diagram of the signal processing system. Code 1 is the flow cell, 2 is the circulation section, 3, 4.10a, i
ob is L/ns, 5, lla, llb are photoelectric detectors, 1
2 is a calculation section, 13 is a storage section, 14 is a display section, and S is a sample.

Claims (1)

[Claims] 1. A flow cell having a flow section through which a specimen passes, and a photoelectric detector for measuring scattered light of the specimen in both directions substantially orthogonal to the traveling direction of the light irradiated onto the specimen from a light source. What is claimed is: 1. A particle analysis apparatus comprising: a plurality of optical systems, each having a plurality of optical systems; and an arithmetic processing circuit section for computing output signals from the plurality of photoelectric detectors. 2. The particle analysis apparatus according to claim 1, wherein the arithmetic processing circuit unit averages output signals of a plurality of photoelectric detectors arranged across the specimen. 3. The particle analysis device according to claim 1, wherein a barrier filter can be inserted into an optical system including the photoelectric detector in order to detect a fluorescently labeled specimen.