JP2003215034A - Thermal lens type analyzer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thermal lens type analyzer capable of detecting fluctuations of light intensity from a light source. <P>SOLUTION: The thermal lens type analyzer 20 has an excitation laser 2 emitting excitation light, an LD 4 emitting detection light, and a flow channel 15 through which a liquid sample is supplied. The excitation light of the excitation laser 2 is branched by a beam sampler 11, and the intensity of the excitation light branched is detected by a PD 12. The detection light of the LD 4 is branched by a beam sampler 13, and the intensity of the detection light branched is detected by a PD 14. A date processing system 10 connected to these PDs 12, 14, by data processing for analyzing the liquid sample, cancels analytical measured data, when the intensity of the excitation light detected by the PDs 12, 14 is a value out of a predetermined acceptable range. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal lens type analyzer, and more particularly to a thermal lens type analyzer for analyzing a solution sample.

[0002]

2. Description of the Related Art A thermal lens type analyzer is a spectroscopic analyzer utilizing the thermal lens effect, which is used for analyzing a sample in a microchemical system and emits excitation light to a solution sample in a chip. A laser and a probe laser that emits detection light for detecting the thermal lens effect are provided.

By the thermal lens, when the solution sample in the chip is focused and irradiated with the excitation light, the specific sample in the solution absorbs the excitation light, and the heat energy released thereafter causes the solvent to be locally generated. The temperature rises and the refractive index changes.

[0004]

However, as shown in FIG. 5, the light intensity of the laser provided in the thermal lens type analyzer decreases with the lapse of time due to deterioration of the laser. In addition, the laser light has random noise and fluctuations during use. For this reason,
The intensity of laser light is not always constant.

An object of the present invention is to provide a thermal lens system analyzer capable of detecting a variation in the intensity of light from a light source.

[0006]

In order to achieve the above-mentioned object, a thermal lens type analyzer according to claim 1 is a chip for containing a solution sample and a thermal lens for the solution sample contained in the chip. A light source for irradiating light so as to form
The thermal-lens type analyzer including an acquisition unit that acquires measurement data for analysis based on light from the solution sample is provided with a monitor unit that monitors the intensity of the light from the light source.

According to the thermal lens system analyzer of the first aspect, since the intensity of the light from the light source is monitored, it is possible to detect the variation in the intensity of the light from the light source.

The thermal lens system analyzer according to claim 2 is
The thermal lens system analyzer according to claim 1, wherein the monitor means includes a data processing unit that corrects the acquired analysis measurement data.

According to the thermal lens system analyzing apparatus of the second aspect, since the acquired measurement data for analysis is corrected,
Accurate measurement values can be obtained according to variations in the intensity of light from the light source.

The thermal lens system analyzer according to claim 3 is
The thermal lens analysis apparatus according to claim 2, wherein the data processing unit corrects the correction measurement data when the intensity of light from the monitored light source is out of a predetermined allowable range. The feature is that it is performed by canceling.

According to the thermal lens system analyzer of the third aspect, the measurement data for analysis is canceled when the intensity of the monitored light from the light source is out of a predetermined allowable range. It is possible to cancel the measurement data for analysis when there is a large fluctuation in the intensity.

The thermal lens system analyzer according to claim 4 is
The thermal lens system analyzer according to claim 2 is characterized in that the value of the analysis measurement data is corrected based on a light intensity function I (t) which is a function of a light source usage time t.

According to the thermal lens type analyzer of the fourth aspect, the light intensity function I which is a function of the usage time t of the light source is used.
Since the value of the measurement data for analysis is corrected based on (t), the effect of the thermal lens system analysis device according to the second aspect can be reliably exhibited.

The thermal lens system analyzer according to claim 5 is
The thermal lens analysis device according to claim 4, wherein the light intensity function I (t) is a linear function.

According to the thermal lens type analyzer of the fifth aspect, the value of the measurement data for analysis is corrected based on the light intensity function I (t) consisting of a linear function. Therefore, the thermal lens of the fourth aspect. The effect of the system analyzer can be easily obtained.

The thermal lens system analyzer according to claim 6 is
The thermal lens system analyzer according to any one of claims 2 to 5, further comprising: an alarm unit that issues an alarm when the correction is performed.

According to the thermal lens system analyzing apparatus of the sixth aspect, since an alarm is issued when the correction is performed, it is possible to easily inform that the variation in the intensity of the light from the light source is detected. .

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a thermal lens system analyzer according to an embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a view showing the schematic arrangement of a thermal lens system analyzer according to the first embodiment of the present invention.

In FIG. 1, a thermal lens system analyzer 20 is shown.
Has a housing 1, and inside the housing 1, an excitation laser 2 (light source) that emits excitation light of a predetermined wavelength, for example, 532 nm.
And a chopper 3 that modulates the excitation light emitted from the excitation laser 2 and a probe semiconductor laser that emits detection light having a wavelength different from that of the excitation light (hereinafter referred to as "LD").
4 (light source), a dichroic mirror 5 that combines the excitation light emitted from the excitation laser 2 and the detection light emitted from the LD 4, and the microchemical system chip 6 provided with the flow path 15 SML lens 7 that focuses the excitation light and the detection light on the solution sample in chip 6 (“Refraction distribution type Selfoc microlens” manufactured by Nippon Sheet Glass Co., Ltd.) A photodiode (hereinafter, referred to as “PD”) 8 for detecting light, a lock-in amplifier 9 connected to each of the PD 8 and the chopper 3, and a data processing system 10 (data processing unit) connected to the lock-in amplifier 9. Are arranged. The chopper 3 is an AOM (acousto-optic device: Acoust
o-Optic Modulator).

Excitation laser 2 and dichroic mirror 5
In between, a beam sampler 11 for 532 nm that splits the pumping light emitted from the pumping laser 2 and a pumping light that is split by the beam sampler 11 are detected 532n.
Between the LD 4 and the dichroic mirror 5, the m monitor PD 12 includes an LD beam sampler 13 and a beam sampler 13 for demultiplexing the detection light emitted from the LD 4.
Monitor PD for detecting the detection light demultiplexed by
14 are arranged respectively, and these PDs 12 and 14 are connected to the data processing system 10 (data processing unit) (monitoring means).

The operation of the spectroscopic analyzer 1 shown in FIG. 1 will be described below.

In FIG. 1, the solution sample is supplied into the channel 15 provided in the chip 6 and having a width of 100 μm and a depth of 300 μm, for example. The excitation laser 2 emits excitation light having a predetermined wavelength, for example, 532 nm, and this excitation light is modulated by the chopper 3. The modulated excitation light passes through the dichroic mirror 5 and is focused and irradiated onto the solution sample supplied into the flow path 15 via the SML lens 7. The irradiated excitation light is absorbed by the sample in the solvent supplied into the flow path 15, and a thermal lens is formed around the condensed irradiation position. Of the excitation light applied to the sample, the light not absorbed by the sample is reflected by a cut-off filter (not shown) so that it does not enter the PD 8.

On the other hand, the LD 4 emits detection light having a wavelength different from that of the excitation light, and the detection light is bent downward by the dichroic mirror 5 so as to be coaxial with the excitation light emitted from the excitation laser 2. Incident on the SML lens 7, and the solution sample supplied into the flow path 15 is focused and irradiated by the SML lens 7. The detection light emitted from the LD4 is
The excitation light diffuses or collects by passing through the inside of the thermal lens where the sample is condensed and irradiated. The light emitted after diverging or condensing from this sample becomes probe light, and the probe light is detected by the PD 8. The detected probe light is input to the lock-in amplifier 9. The excitation light from the excitation laser can also serve as the detection light.

The intensity of the probe light detected by the PD 8 changes in accordance with the thermal lens formed by the absorption of the excitation light by the sample in the solvent and is synchronized with the excitation light modulation period by the chopper 3. It changes. Therefore, the probe light detected by the PD 8 is input to the lock-in amplifier 9, amplified by the lock-in amplifier 9 and converted into a signal, and the amplified probe-lighted signal is locked in the lock-in amplifier 9. Is detected in synchronization with the excitation light modulation period by the chopper 3. The data processing system 10 converts the detected probe light into data for analysis as a measurement value of a solution sample, performs analysis measurement data processing, and analyzes the solution sample.

A beam sampler 11 for 532 nm
And the excitation light intensity is detected via PD12, and L
The detected light intensities are detected via the D beam sampler 13 and the PD 14, and the detected light intensities are input to the data processing system 10.

FIG. 2 is a thermal lens type analyzer 20 of FIG.
It is a flow chart of measurement data processing for analysis performed by.

This process is performed by the thermal lens system analyzer 2 of FIG.
0 is executed by the data processing system 10 and the measurement data for analysis is canceled when the excitation light intensity detected through the beam sampler 11 and the PD 12 is out of a predetermined allowable range.

In FIG. 2, first, the upper and lower limits of the excitation light intensity are set (step S1). The upper limit value and the lower limit value of this excitation light intensity are determined experimentally,
With respect to the excitation light intensity of 200 mJ when the excitation light is the stationary light, the upper limit value is, for example, 30% increase of 260 mJ, and the lower limit value is, for example, 30% decrease of 140 mJ (FIG. 3).
(A)).

Then, the excitation light intensity is detected, and the measurement data for analysis of the solution sample is acquired as described above with reference to FIG. 1 (acquisition means) (step S2), and the detected excitation light intensity is the upper limit value. It is determined whether or not the above (step S
3) Then, it is determined whether the detected excitation light intensity is less than or equal to the lower limit value (step S4).

As a result of the discrimination in steps S3 and S4, is the detected excitation light intensity above the upper limit (A in FIG. 3)?
Alternatively, when it is less than or equal to the lower limit (B in FIG. 3), that is, when the value is outside the allowable range, an alarm is issued by an alarm device (not shown) (step S5), and the measurement data for analysis is canceled (step S6). This process ends.

As a result of the determination in steps S3 and S4, when the detected excitation light intensity is below the upper limit value or above the lower limit value, that is, within the allowable range,
This process ends.

According to the processing of FIG. 2, when the detected excitation light intensity is equal to or higher than the upper limit value (A in FIG. 3) or lower than the lower limit value (B in FIG. 3), that is, outside the allowable range. If it is (YES in step S3 or S4), the excitation laser 2
In consideration of the fact that the noise and fluctuations present in the excitation light and the random noise and fluctuations present in the excitation light (Fig. 3 (a)) affect the values of the measurement data for analysis of the solution sample (Fig. 3 (b)). Since the measurement data is canceled (step S6), the measurement data for analysis can be canceled when the deterioration of the excitation laser 2 or the random noise or fluctuation present in the excitation light is large.

When the detected excitation light intensity is out of the allowable range (YES in step S3 or S4), an alarm is issued by the alarm device (step S5). It is possible to easily inform that the random noise or large fluctuation is detected.

In the first embodiment, the analysis measurement data is canceled when the excitation light intensity of the excitation laser 2 is out of the allowable range. However, acquisition of the analysis measurement data is prohibited. May be.

A thermal lens system analyzer according to the second embodiment of the present invention will be described below.

The configuration of the thermal lens system analyzer according to the second embodiment of the present invention is the same as that of the thermal lens system analyzer 2 of FIG.
Same as 0.

FIG. 4 is a thermal lens type analyzer 20 of FIG.
It is a flow chart of measurement data processing for analysis performed by.

This processing is performed by the thermal lens system analyzer 2 of FIG.
It is executed by the zero data processing system 10 and corrects the measurement data for analysis by the deterioration amount of the excitation laser 2 when the excitation laser 2 is deteriorated.

In FIG. 4, first, the light intensity of the excitation laser 2 when the excitation laser 2 is purchased is measured by the data processing system 10.
(Step S1), and a calibration curve showing the degree of decrease in the intensity of the laser light due to the deterioration of the excitation laser 2 with respect to the usage time of the excitation laser 2 is stored in the data processing system 10 (step S2). This calibration curve may be provided by a laser vendor.

Then, the excitation light intensity is detected, and the measurement data for analysis of the solution sample is acquired as described above with reference to FIG. 1 (acquisition means) (step S3). At this time, the detected excitation light intensity is measured by the beam sampler 11 and P before the excitation laser 2 irradiates the solution sample with the excitation light.
Input to the data processing system 10 via D12.

Next, the excitation light intensity detected in step S3 is compared with the calibration curve stored in step S2 (step S4). The detected excitation light intensity is lower than the intensity of the excitation laser 2 at the time of purchase of the excitation laser 2, and the measurement data for analysis of the solution sample is converted into the excitation laser 2 based on the result compared in step S5. A correction coefficient to compensate for the deterioration amount of
5), the value of the analytical measurement data of the solution sample is corrected using the correction coefficient determined in step S5, and the analytical measurement data of the solution sample is changed to a value that compensates for the deterioration of the excitation laser 2 ( In step S6), this process ends.

According to the processing of FIG. 4, the comparison result between the detected excitation light intensity and the stored calibration curve (step S4)
The correction coefficient is determined based on the above (step S5), and the value of the measurement data for analysis of the solution sample is corrected (step S5).
Since 6), accurate measurement values can be obtained according to the deterioration of the excitation laser 2.

In the above steps S1 and S2, the light intensity of the excitation laser 2 at the time of purchase of the excitation laser 2 and the calibration curve with respect to the usage time of the excitation laser 2 are stored. Before measurement, at least two points having different excitation light intensities with respect to the reference sample are measured by using an ND filter or the like, and a calibration curve of the measured value corresponding to the excitation light intensity is created and stored even if this calibration curve is stored. Good.

In the process shown in FIG. 4, when the value of the measurement data for analysis of the solution sample is corrected (step S
6), an alarm device may give an alarm. As a result, it is possible to easily notify that the deterioration of the excitation laser 2 or the random noise or fluctuation present in the excitation light is large.

Although the correction coefficient is determined based on the calibration curve in the processing of FIG. 4, the correction function I (t) (t is the operating time of the excitation laser 2) may be used instead of the calibration curve. Good. This correction function I (t) is such that the correction coefficient fluctuates every time the excitation light is detected based on the excitation light intensity before the solution sample is irradiated with the excitation light, for example, as shown in FIG. , The correction coefficient is the correction function I (t)
May be determined based on. As a result, more accurate measurement values can be obtained according to the deterioration of the excitation laser 2 at the time of detecting the excitation light, the random noise existing in the excitation light, and the magnitude of fluctuation.

The process of FIG. 4 is preferably executed after the process of FIG. As a result, the pumping laser 2 is canceled after the measurement data for analysis is canceled in consideration of the deterioration of the pumping laser 2 and the random noise and fluctuation existing in the pumping light.
Of the measurement data for analysis in consideration of deterioration of the laser
Since the value is changed to a value that compensates for the deterioration amount of, more accurate measurement data can be obtained.

In the first and second embodiments, the pumping light intensity of the pumping laser 2 is detected.
The detected light intensity of may be detected. In this case, the permissible range of the detected light intensity is set instead of the permissible range of the excitation light intensity. More preferably, it is desirable to detect the excitation light intensity of the excitation laser 2 and the LD 4. In this case, both the allowable range of the excitation light intensity and the allowable range of the detected light intensity are set.

The analyzer using the above-mentioned monitoring means is not limited to the thermal lens type analyzer which causes the thermal lens in the sample to be analyzed. The present invention can be applied to an analyzer in which fluctuations in the amount of light emitted from a light source and a decrease in the amount of light due to deterioration of the light source affect the accuracy of analysis.

[0050]

As described in detail above, according to the thermal lens system analyzer of the first aspect, since the intensity of the light from the light source is monitored, it is possible to detect the variation in the intensity of the light from the light source. You can

According to the thermal lens system analyzer of the second aspect, since the acquired measurement data for analysis is corrected,
Accurate measurement values can be obtained according to variations in the intensity of light from the light source.

According to the thermal lens type analyzer of the third aspect, since the measurement data for analysis is canceled when the intensity of the light from the monitored light source is out of the predetermined allowable range, the light from the light source is canceled. It is possible to cancel the measurement data for analysis when there is a large fluctuation in the intensity.

According to the thermal lens system analyzer of the fourth aspect, the light intensity function I which is a function of the usage time t of the light source is used.
Since the value of the measurement data for analysis is corrected based on (t), the effect of the thermal lens system analysis device according to the second aspect can be reliably exhibited.

According to the thermal lens type analyzer of the fifth aspect, the value of the measurement data for analysis is corrected based on the light intensity function I (t) which is a linear function. Therefore, the thermal lens of the fourth aspect. The effect of the system analyzer can be easily obtained.

According to the thermal lens system analyzing apparatus of the sixth aspect, since an alarm is issued when the correction is performed, it is possible to easily inform that the variation in the intensity of the light from the light source is detected. .

[Brief description of drawings]

FIG. 1 is a diagram showing a schematic configuration of a thermal lens system analyzer according to an embodiment of the present invention.

FIG. 2 is a flowchart of analysis measurement data processing executed by the thermal lens system analyzer 20 of FIG.

FIG. 3 is a graph showing cancellation of analytical measurement data in the process of FIG. 2, (a) showing a relationship between laser light intensity and measurement time, and (b) showing measurement of a solution sample. The relationship between the value and the measurement time is shown.

FIG. 4 is a flowchart of analysis measurement data processing executed by the thermal lens system analyzer 20 of FIG.

FIG. 5 is a graph showing a change in laser light intensity of a laser with respect to usage time.

[Explanation of symbols]

1 case 2 pump laser 4 Semiconductor laser for probe 5 dichroic mirror 6 chips 7 SML lens 10 Data processing system 11 532nm beam sampler Monitor PD for 12532nm 13 LD beam sampler 14 LD monitor PD 20 Thermal lens type analyzer

Claims (6)

[Claims] 1. A chip for containing a solution sample, a light source for irradiating the solution sample contained in the chip with light so as to form a thermal lens, and measurement data for analysis based on the light from the solution sample. A thermal lens analysis device comprising: an acquisition unit that acquires the light intensity of the light from the light source. 2. The thermal lens system analyzer according to claim 1, wherein the monitor unit includes a data processing unit that corrects the acquired measurement data for analysis. 3. The data processing unit performs the correction by canceling the analysis measurement data when the intensity of light from the monitored light source is out of a predetermined allowable range. The thermal lens system analyzer according to claim 2, which is characterized in that. 4. The data processing unit corrects the value of the measurement data for analysis based on an intensity function I (t) of light which is a function of a usage time t of the light source. 2. The thermal lens system analyzer according to 2. 5. The thermal lens system analyzer according to claim 4, wherein the light intensity function I (t) is a linear function. 6. The thermal lens system analyzer according to claim 2, further comprising: an alarm unit that outputs an alarm when the correction is performed.