Microparticle analysis apparatus to improve analytical precision based on detection of forward-scattered light

1. An analysis apparatus, comprising:

a light detector configured to detect light emitted from an analysis target that is irradiated by an optical source; and

a filter circuit comprising:

a first channel having an input side and an output side;

a second channel having a high-pass filter; and

a switching element configured to switch between the first channel and the second channel based on a relationship of a frequency of the detected light and a threshold frequency value,

wherein the high-pass filter is configured to remove low frequency noise included in the detected light.

2. The analysis apparatus according to claim 1 , wherein the analysis target includes a microparticle.

3. The analysis apparatus according to claim 2 , wherein the detected light includes forward-scattered light emitted from the microparticle.

4. The analysis apparatus according to claim 1 , wherein the light detector is integral with the filter circuit.

5. The analysis apparatus according to claim 1 , wherein the switching element is further configured to connect to the high-pass filter based on the frequency of the detected light that is one of equal to or higher than 200 kHz.

6. The analysis apparatus according to claim 1 , further comprising:

a zero-order light removal unit configured to block zero-order light,

wherein the zero-order light removal unit is between the analysis target and the light detector.

7. The analysis apparatus according to claim 6 , wherein the high-pass filter is further configured to remove the low frequency noise included in leakage light that avoids the zero-order light removal unit and enters the light detector.

8. The analysis apparatus according to claim 1 , wherein the high-pass filter is further configured to remove the low frequency noise that is lower than 2 kHz.

9. The analysis apparatus according to claim 1 , wherein

the second channel having the high-pass filter is connected to the input side of the first channel.

10. The analysis apparatus according to claim 1 , wherein the switching element is further configured to connect to an output side of the second channel.

11. The analysis apparatus according to claim 10 , wherein the filter circuit further comprises an amplifier configured to amplify forward-scattered light emitted from the analysis target.

12. An analysis method, comprising:

removing, by a high-pass filter, low frequency noise included in light entering a light detector from an analysis target; and

switching, a switching element included in a filter circuitry, between a first channel and a second channel based on a relationship of a frequency of forward-scattered light, emitted from the analysis target and a threshold frequency value,

wherein the first channel comprises an input side and an output side,

wherein the second channel comprises the high-pass filter, and

wherein the forward-scattered light is used to analyze the analysis target.

13. A microparticle analysis apparatus, comprising:

an optical source configured to irradiate a microparticle in a channel;

a forward-scattered light (FS) detector configured to detect forward-scattered light emitted from the microparticle that is irradiated by the optical source;

a back-scattered light (BS) detector configured to detect back-scattered light emitted from the microparticle;

a fluorescence (FL) detector configured to detect fluorescence from the microparticle;

a first channel having an input side and an output side;

a second channel having a high-pass filter; and

filter circuit comprising a switching element configured to switch between the first channel and the second channel based on a relationship of a frequency of the forward-scattered light and a threshold frequency value,

wherein the high-pass filter is configured to remove low frequency noise included in the forward-scattered light entering the FS detector.