JP2010019562A - Two-dimensional distribution measuring instrument using laser beam - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a two-dimensional distribution measuring instrument using a laser beam for measuring a density distribution with high precision in a measuring field with a large density deviation of a molecule to be measured. <P>SOLUTION: The two-dimensional distribution measuring instrument includes a beam expander which outputs a sheetlike laser beam to irradiate the molecule to be measured of the measuring field, the cell provided between the beam expander and the measuring field to have a fluorescent substance sealed therein and permitting the laser beam to pass, a fluorescence measuring means for measuring the fluorescent intensity of the fluorescence emitted from the fluorescent substance in the cell and the fluorescent intensity of the fluorescence emitted from the molecule to be measured of the measuring field, and a measuring means for normalizing the fluorescent intensity of the measuring field by the fluorescent intensity in the cell using the position data of the cell and the position data of the measuring field, so that a density distribution is measured with high precision. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a measuring apparatus using a laser beam that measures a two-dimensional distribution related to characteristics such as concentration and temperature of a molecule to be measured using a laser-induced fluorescence method.

  As a method to measure the two-dimensional distribution of the concentration and temperature of the molecule to be measured, a measurement method combining the laser sheet method using a two-dimensional sheet-like laser beam and the laser induced fluorescence (LIF), Planer -LIF (hereinafter abbreviated as P-LIF) is conventionally used.

  FIG. 6 shows a schematic configuration of a two-dimensional concentration measuring apparatus using a general P-LIF. In this measurement apparatus, the laser oscillated from the excitation pulse laser apparatus 1 is input to the wavelength tunable dye laser apparatus 2 and oscillates a beam-shaped laser beam 11 converted to a wavelength corresponding to the electron excitation energy of the molecule to be measured. . The laser beam 11 is spread by a beam expander 13 into a sheet shape having a thickness of about 1 mm, and is shaped into a laser sheet beam 12 having a width parallel to the emission direction by the convex lens 20 to form a measurement field 10 containing a molecule to be measured. Irradiated. The spread of the laser sheet light in the figure is almost parallel to the paper surface.

  A molecule to be measured in the measurement field 10 absorbs a part of the laser sheet light 12 to be in an excited state, and emits fluorescence having a specific wavelength when returning to the ground state. The fluorescence is condensed by the lens 5 from a direction substantially orthogonal to or oblique to the laser sheet light and measured as two-dimensional distribution data of fluorescence intensity by the CCD camera 4. An optical filter 6 is installed between the measurement field 10 and the lens 5, and stray light such as scattered light of the laser sheet light 12 is reduced by the optical filter 6 to selectively guide the fluorescence of the molecule to be measured to the lens 5. The measured data is fetched into the control computer 3 which is a control device on line 8. Further, the simultaneous measurement means provided in the control computer 3 adjusts the oscillation of the excitation pulse laser device 1 and the exposure timing of the CCD camera 4 through the synchronization line 9.

  In P-LIF, the fluorescence intensity is proportional to the product of the concentration of the molecule to be measured and the intensity of the laser sheet light. The laser sheet light generally has an inhomogeneous intensity distribution, and it is difficult to irradiate the laser sheet light 12 having a uniform intensity distribution in the entire region to be measured. Therefore, in order to accurately measure the concentration of the molecule to be measured, that is, the fluorescence intensity, it is necessary to remove the influence of the change in the intensity distribution of the laser sheet light 12 from the fluorescence intensity measured by the CCD camera 4.

  As a method of measuring the intensity of the laser sheet light 12, before the measurement at the measurement field 10, a cell 7 in which a fluorescent substance having a uniform predetermined concentration is inserted is inserted into the measurement field 10, and the fluorescence intensity of the cell 7 by the laser sheet light is measured. A method for measuring the current is known. The concentration of the fluorescent material sealed in the cell 7 is uniform, and the fluorescence intensity of the cell 7 is proportional to the intensity of the laser sheet light 12. The measurement value is normalized by dividing the fluorescence intensity of the laser sheet light measured in advance as described above to remove the influence of the intensity distribution of the laser sheet light, and the measurement object 10 is measured. Accurately measure molecular concentration.

  In Patent Document 1, a cell in which a fluorescent material is sealed is installed between a measurement field and a beam expander, and the fluorescence emitted from the fluorescent material in the cell is measured separately from the CCD camera that measures the fluorescence in the measurement field. A measurement device that installs a CCD camera, measures the fluorescence intensity distribution of the measurement field and the cell simultaneously with two CCD cameras, and normalizes the measurement value by dividing the fluorescence intensity distribution of the measurement field by the fluorescence intensity distribution of the cell. It is shown.

  In Patent Document 2, a beam splitter that branches a part of a laser beam is provided between a beam expander and a measurement field, the laser beam branched by the beam splitter is irradiated onto a glass plate coated with a fluorescent material, There is shown a measuring apparatus that measures the fluorescence intensity emitted from a fluorescent substance and normalizes the fluorescence intensity distribution by dividing the fluorescence intensity distribution of the measurement field by this fluorescence intensity distribution.

Japanese Patent Laid-Open No. 7-198611 Japanese Unexamined Patent Publication No. 9-210909

  However, in the method of measuring the intensity of the laser sheet light in advance before the measurement of the molecule to be measured, the fluorescence intensity of the measurement field 10 and the intensity of the laser sheet light 12 cannot be measured simultaneously. The laser sheet light output varies greatly with time, and it is therefore difficult to compare the fluorescence intensities of a plurality of measurement data that cannot be synchronized in time.

  In P-LIF, the intensity of the laser sheet light attenuates as the distance from the laser device increases due to Rayleigh scattering or absorption for exciting the molecule to be measured, and the amount of attenuation is proportional to the concentration of the molecule to be measured. Therefore, as in the apparatus described in Patent Document 1, when the fluorescence intensity of the measurement field is divided by the uniform fluorescence intensity of the cell in which the fluorescent substance having a uniform concentration is enclosed, the concentration distribution of the fluorescent substance inside the measurement field and the cell is obtained. A measurement error due to the difference occurs. Patent Document 1 does not disclose correction for attenuation of laser sheet light.

  In the apparatus described in Patent Document 2, the intensity distribution in the width direction of the laser sheet light can be corrected, but the attenuation of the laser sheet light in the irradiation direction of the laser sheet light is not described.

  In addition, both of the apparatuses described in Patent Document 1 and Patent Document 2 require that the laser sheet light be completely parallel light, and can measure the density when the laser sheet light cannot be made parallel or adjustment is insufficient. Or measurement errors may occur. Furthermore, the absolute value of the concentration could not be measured by any of the above methods.

  An object of the present invention is to provide a two-dimensional distribution measurement apparatus using a laser capable of measuring a concentration distribution with high accuracy even in a measurement field where the concentration deviation of molecules to be measured in the measurement field is large. Another object of the present invention is to provide a two-dimensional distribution measuring apparatus using a laser capable of measuring the absolute value of concentration.

  The present invention relates to a laser device that outputs a laser beam, a beam expander that converts a laser beam into laser sheet light, a measurement field having a molecule to be measured, and laser sheet light irradiated to the molecule to be measured in the measurement field In the two-dimensional distribution measuring apparatus, comprising: a fluorescence measuring means for measuring the fluorescence intensity of the molecule to be measured by: a control device for adjusting the timing of the laser sheet light irradiation time of the laser apparatus and the measuring time of the fluorescence measuring means; Between the laser device and the measurement field, a cell is provided in which a fluorescent material is sealed and irradiated with laser sheet light, and the fluorescence emitted by the molecule to be measured in the measurement field and the fluorescent material sealed in the cell is measured. Means for simultaneous measurement by means of means, and the fluorescence intensity and position information of the cell and the fluorescence intensity and position information of the measurement field. Characterized in that the fluorescence intensity of the measured molecular that provided a normalization means for normalizing.

  Further, the normalizing means calculates the intensity of the laser sheet light in the measurement field by obtaining the characteristic of the molecule to be measured from the fluorescence intensity of the cell by the laser sheet light, and calculates the fluorescence intensity of the measured molecule in the measurement field. The characteristic distribution of the molecule to be measured in the measurement field is calculated by normalizing with the intensity of the laser beam at.

  Further, the characteristic of the molecule to be measured in the normalizing means includes an absorption coefficient of the molecule to be measured, and a proportional constant relating to the fluorescence intensity and the laser sheet light intensity.

  Further, the simultaneous measurement means is characterized in that the fluorescence emitted from the molecule to be measured in the measurement field and the fluorescent substance enclosed in the cell is simultaneously measured by a single fluorescence measurement means.

  Furthermore, a beam splitter provided between the beam expander and the measurement field and for branching the sheet laser beam, and a beam splitter that passes through the beam splitter and is parallel to the laser sheet beam that irradiates the measurement field. Fluorescence emitted from the mirror that reflects the branched laser sheet light, the cell that passes the laser light branched by the beam splitter, the molecule to be measured in the measurement field, and the fluorescent material enclosed in the cell is a single fluorescence. It is characterized by comprising simultaneous measuring means for simultaneously measuring by the measuring means.

  Further, a beam splitter provided between the beam expander and the measurement field and for branching the sheet-like laser beam, and the beam splitter so as to be parallel to the laser beam that passes through the beam splitter and irradiates the measurement field. A mirror that reflects the laser beam branched by the beam splitter, the cell that allows the laser beam branched by the beam splitter to pass through, a cell fluorescence measurement means that measures the fluorescence intensity of the cell, a molecule to be measured in the measurement field, and the cell And a simultaneous measurement means for simultaneously measuring the fluorescence emitted from the fluorescent material enclosed in the cell by the fluorescence measurement means and the cell fluorescence measurement means.

  Further, a beam splitter installed between the laser device and the beam expander and for branching the beam-shaped laser beam, and the laser beam that passes through the beam splitter and irradiates the measurement field so as to be parallel to the laser beam. A mirror that reflects the laser light branched by the beam splitter, a beam expander that converts the laser light reflected by the mirror into laser sheet light and irradiates the cell, and a cell fluorescence measuring means that measures the fluorescence intensity of the cell And a simultaneous measurement means for simultaneously measuring fluorescence emitted from a molecule to be measured in the measurement field and a fluorescent substance enclosed in the cell by the fluorescence measurement means and the cell fluorescence measurement means.

  Furthermore, the fluorescent substance sealed in the cell is the same substance as the molecule to be measured in the measurement field.

  ADVANTAGE OF THE INVENTION According to this invention, the measuring device using the laser beam which can measure the fluorescence intensity in the measurement field where the density | concentration deviation of a molecule | numerator to be measured is severe with high precision is realizable. Furthermore, it is possible to realize a measuring apparatus using laser light that can statistically process an average value and fluctuation components of a plurality of measurement data such as a two-dimensional concentration distribution with high accuracy.

  Moreover, in said measuring apparatus, the measuring apparatus which can measure the absolute density | concentration of a measurement field is realizable by enclosing the same substance as a measuring object in a cell.

Hereinafter, a measuring apparatus using laser light according to the present invention will be described with reference to the drawings.
[First Embodiment]
The overall schematic configuration of the first embodiment of the present invention is shown in FIG. This measuring apparatus includes a laser apparatus composed of an excitation pulse laser apparatus 1 and a tunable dye laser apparatus 2, a beam expander 13, a CCD camera 4 serving as a fluorescence measuring means, a control computer 3 serving as a control apparatus, a cell 7, a measurement field. 10 is composed.

  The laser oscillated by the excitation pulse laser device 1 is oscillated by the wavelength tunable dye laser device 2 as a beam-like laser beam 11 converted to a wavelength corresponding to the electron excitation energy of the molecule to be measured. The laser beam 11 is spread by a beam expander 13 into a sheet-like laser sheet beam 12 that is diffused in parallel with the paper surface, and passes through a cell 7 encapsulating a fluorescent substance having a predetermined concentration composed of molecules of the same type as the molecule to be measured. The measurement field 10 containing the molecule to be measured is irradiated.

  The fluorescence emitted from the cell 7 and the measurement field 10 is collected by the lens 5, and the two-dimensional distribution of the fluorescence intensity is measured by the CCD camera 4. The two-dimensional distribution of fluorescence intensity is two-dimensional digital data corresponding to the number of CCD pixels constituting the CCD camera 4. The two-dimensional distribution data of the measured fluorescence intensity is captured by the control computer 3 at line 8 and processed. Further, the control computer 3 adjusts the oscillation timing of the excitation pulse laser device 1 and the exposure timing of the CCD camera 4 through the synchronization line 9. In the two-dimensional distribution data of the fluorescence intensity measured by the CCD camera 4, the fluorescence intensity of the cell 7 is continuously recorded on the laser device side, and the fluorescence intensity of the measurement field 10 is continuously recorded in a region away from the laser device.

  An optical filter 6 is installed between the measurement field 10 and the lens 5 to reduce the laser sheet light 12, its scattered light, and other stray light. The laser device may use a wavelength tunable laser such as an excimer laser instead of the excitation pulse laser device 1 and the wavelength tunable dye laser device 2. Further, the laser sheet light 12 may be a laser sheet light having a parallel width by combining a beam expander and a convex lens as in FIG.

The pulse width of the laser light of the excitation pulse laser device 1 is several nanoseconds, and the fluorescence emission duration is about 1 microsecond. The fluorescence intensity decays exponentially after irradiation with excitation laser light. Therefore, the exposure time of the CCD camera 4 is preferably set to several nanoseconds to several hundred nanoseconds.
[Calculation of measured molecule concentration]
The two-dimensional distribution data of the fluorescence intensity _If of the measurement field 10 measured as described above is proportional to the product of the concentration C of the molecule to be measured in the measurement field 10 and the intensity I of the laser sheet light 12. That is, there is the following relationship between the fluorescence intensity _If and the intensity I of the laser beam.
_If = aCI (Formula 1)
Here, a is a proportionality constant determined by the characteristics of the measuring device such as the CCD camera 4 and the optical filter 6. Therefore, the concentration C of the molecule to be measured can be obtained by dividing the measured fluorescence intensity _If by the intensity I of the laser sheet light 12. In order to obtain the two-dimensional concentration distribution of the molecule to be measured, the fluorescence intensity _If measured for each pixel of the pixel of the CCD camera 4 is divided by the intensity I of the laser sheet light at each pixel. The intensity I of the laser sheet light of each pixel is calculated in consideration of the non-uniformity of the emitted laser sheet light 12 and the absorption attenuation of the laser sheet light by the molecules to be measured.

Hereinafter, a method of calculating the laser sheet light intensity I of each pixel will be described with reference to FIG. FIG. 2A shows the relationship between the measurement area of the CCD camera 4 and the irradiation direction of the laser sheet light 12 as seen from the direction orthogonal to the spreading direction of the laser sheet light. FIG. 2B shows the distribution of the intensity I and the fluorescence intensity _If of the laser sheet light 12 corresponding to the X direction in FIG. FIG. 2C shows the distribution of the intensity I of the laser sheet light and the fluorescence intensity _{If in} the AA cross section of FIG.
[Correction of non-uniformity of laser light]
First, calculation for correcting nonuniformity when the laser sheet light 12 is not parallel light will be described. In FIG. 2A, the fluorescence intensity 31 of the cell 7 and the fluorescence intensity 32 of the measurement field 10 are measured in the measurement region 30 of the CCD camera 4. The laser sheet light 12 in FIG. 1 can be regarded as irradiating the measurement region 30 while spreading from the virtual light source 33 corresponding to the focal point of the beam expander 13 at the spread angle θ. Hereinafter, the Y direction in this figure is referred to as the width direction of the laser sheet light 12, and the X direction is referred to as the irradiation direction of the laser sheet light 12.

The laser sheet light 12 is formed by spreading the beam-shaped laser light 11 oscillated from the wavelength tunable dye laser device 2 in FIG. 1 into a sheet shape by the beam expander 13, and therefore the intensity in the width direction of the laser sheet light 12. Is not uniform. In the measurement region 30 of the CCD camera 4, a distribution of the fluorescence intensity _If as shown by the solid line in FIG. 2C is obtained for the cross section AA of the laser sheet 12 having the fluorescence intensity 31 of the cell 7 in the width direction. Since the concentration C of the fluorescent substance in the cell 7 is uniform in the width direction, and the fluorescence intensity _If is proportional to the intensity I of the laser sheet light 12, the width direction A- of the laser sheet light 12 is determined from the distribution of the fluorescence intensity _If . A distribution of intensity I in the A section is obtained.

  Next, from the distribution of the fluorescence intensity 31 of the cell 7, the spread angle θ of the laser sheet light 12 and the position of the light source 33 of the laser sheet light 12 are calculated. The laser sheet light 12 is emitted from a light source 33 as a light beam 34. The intensity I of the laser sheet light 12 at an arbitrary point in the measurement area 30 of the CCD camera 4 is calculated from the fluorescence intensity 31 of the cell 7, the spread angle θ of the sheet light 12, the position of the light source 33, and the light source 33. Calculate from the distance L to the point.

When the distribution data of the fluorescence intensity 31 of the cell 7 is insufficient and the light source 33 of the laser sheet light 12 cannot be calculated, the light source is determined from the positional relationship between the beam expander 13 and the cell 7 and the spread angle of the laser sheet light 12. 33 may be determined. Further, when the laser sheet light 12 is completely parallel light, it is preferable to calculate only the following laser attenuation correction.
[Correction of laser beam absorption attenuation]
Further, calculation for correcting the absorption attenuation of the laser sheet light 12 by the molecule to be measured will be described. A single light beam 34 emitted from the light source 33 will be described with respect to the fluorescence intensity 32 of the measurement field 10. FIG. 2B shows the distribution of the intensity I and the fluorescence intensity _If of the laser sheet light in the irradiation direction of the light beam 34. The solid line is the distribution of the fluorescence intensity _If measured by the CCD camera 4, the alternate long and short dash line is the intensity distribution of the laser sheet light 12 calculated considering only the spread of the laser sheet light 12, and the dotted line is further measured. The distribution of the intensity I _abs of the laser sheet light 12 calculated by adding the light absorption factor by the molecule is shown.

The absorption coefficient ε relating to the absorption of the light of the molecule to be measured is given by the cell 7 when the light intensity I ₀ before entering the cell 7 is transmitted through the cell 7 having the width L _cell as I _Lcell. It is expressed by the following equation using the concentration C of the molecule to be measured.
Log (I _Lcell / I ₀ ) = εCL _cell (Expression 2)
In this measuring apparatus, since the size L _cell of the cell 7 and the concentration C of the molecule to be measured are known, the extinction coefficient ε is calculated using the fluorescence intensity 31 of the cell 7. In addition, when the extinction coefficient ε of the molecule to be measured is known, the value may be used.

From the fluorescence intensity 31 of cell 7, the relationship of the fluorescence intensity I _f to the concentration C of the intensity I and the measured molecular laser light sheet 12 (1), to calculate the proportionality constant a.

Using the proportionality constant a and the extinction coefficient ε calculated by the above formulas (1) and (2), the fluorescence intensity 32 of the measurement field 10 is sequentially covered in the irradiation direction away from the light source 33 sequentially from the light source 33 side for each CCD pixel. The intensity I _abs of the laser sheet light 12 in consideration of light absorption by the measurement molecule is calculated. The density C can be calculated from the intensity I _abs of the laser sheet light 12 and the fluorescence intensity _{If of} each pixel.

By using the distribution of the intensity I _abs of the laser sheet light 12 in consideration of the absorption of light by the molecules to be measured according to the irradiation direction away from the region close to the light source 33 obtained by the above method, It is possible to obtain a highly accurate concentration distribution of the molecule to be measured, in which the influence of the intensity reduction and the absorption of the laser sheet light 12 by the molecule to be measured is reduced. The above calculation is performed using predetermined software in the control computer. That is, the normalization means and the calculation means are configured on these hardware and software.

  P-LIF measures with a highly sensitive CCD camera, but averages the two-dimensional fluorescence intensity distribution data measured continuously in order to reduce noise or measure the time average distribution of concentration in an unsteady measurement field. Often to do. However, as already described, the fluorescence intensity strongly depends on the elapsed time from the laser light irradiation, and the measured fluorescence intensity differs greatly only when the laser light irradiation and the exposure timing of the CCD camera are slightly shifted. Therefore, the laser intensity measured by a laser power meter or the like and the measured fluorescence intensity may not be proportional.

  In this embodiment, the intensity of the laser beam to be irradiated is highly accurate by measuring with a single CCD camera that uses the fluorescence of a uniform concentration cell provided in the same measurement field as the simultaneous measurement means simultaneously with measurement of the measurement field. It can be corrected. Rather than simply averaging the two-dimensional distribution data of the fluorescence intensity measured by the CCD camera 4, the fluorescence intensity of the molecule to be measured is calculated by normalizing with the laser light intensity accurately obtained by the above method. Two-dimensional concentration distribution data can be obtained with high accuracy.

When the same substance as the molecule to be measured is used for the cell 7, the absolute value of the molecule to be measured can be obtained. In addition, another fluorescent substance may be enclosed instead of the same substance. In this case, it is preferable to obtain a proportional constant between the ratio of the fluorescence intensity emitted from the separately encapsulated fluorescent substance and the molecule to be measured and the intensity I of the laser sheet light to be irradiated and the fluorescence _If .
[Second Embodiment]
FIG. 3 shows an overall schematic configuration of the second embodiment of the present invention. In the figure, the laser sheet light spreads in a direction perpendicular to the paper surface. The basic operation is the same as that of the first embodiment, and different points will be described below.

  A beam splitter 14 is installed between the beam expander 13 and the measurement field 10. Adjustment is made by the mirror 15 so that the laser sheet light 12 transmitted through the beam splitter 14 and the branched laser sheet light 12 'are parallel to each other. The cell 7 is arranged on the light source side in the measurement region of the CCD camera 14. A light shielding plate 16 is provided between the laser sheet light 12 and the cell 7 for masking so that the fluorescence of the molecule to be measured emitted by the laser sheet light 12 is not measured by the CCD camera 4. It is desirable to combine the beam expander 13 and a convex lens (not shown) so that the laser sheet light 12 and the laser sheet light 12 'are parallel lights having parallel widths.

  Using the distance L between the beam splitter 14 and the measurement field 10, the distance L ′ between the beam splitter 14 and the cell 7, and the fluorescence intensity of the cell 7, the distribution of the intensity I of the laser sheet light 12 that irradiates the measurement field 10 is calculated. calculate. Further, by measuring the ratio of the intensity of the laser sheet light 12 and the intensity of the laser sheet light 12 ′ in advance, the concentration of the measurement field 10 can be determined from the fluorescence intensity distribution measured by the CCD camera 4 as in the first embodiment. Distribution can be measured. When the sheets 12 and 12 ′ are not parallel light, the distance I from the beam expander 13 may be used to correct the intensity I of the laser sheet light 12 that irradiates the measurement field 10 and the cell 7.

In the present embodiment, even when the cell 7 cannot be installed in the vicinity of the measurement field 10, the fluorescence intensity of the measurement field 10 and the fluorescence intensity of the cell 7 can be measured simultaneously with a single CCD camera as a simultaneous measurement unit. It is possible to obtain highly accurate two-dimensional concentration distribution data in consideration of attenuation of the laser sheet light due to absorption of the laser sheet light by the molecule to be measured.
[Third Embodiment]
FIG. 4 shows the overall schematic configuration of the third embodiment of the present invention. The basic operation is the same as that of the second embodiment, and different points will be described below.

  The difference from the second embodiment is that the measurement field 10 is measured by the CCD camera 4, and additionally a cell-dedicated CCD camera 4 ′, a condenser lens 5 ′, and an optical filter 6 ′ are separately provided as cell fluorescence measurement means. This is a point at which the cell 7 is measured. The laser device 1 and the CCD cameras 4 and 4 ′ adjust the oscillation and exposure timings by the simultaneous measurement means provided in the control computer 3 via the synchronization line 9. The fluorescence intensity distribution data measured by the CCD camera 4 ′ is also taken into the control computer 3 through the line 8.

Although it is difficult to synchronize the exposure times of the CCD cameras 4 and 4 'with an error of several nanoseconds or less, the absolute values cannot be compared. However, according to the present embodiment, the cells within the photographing range of the single CCD camera 4 can be used. Even when 7 cannot be installed, it is possible to measure the relative concentration distribution with higher accuracy than the conventional example in consideration of the attenuation of the laser sheet light due to the absorption of the laser sheet light by the molecule to be measured.
[Fourth Embodiment]
FIG. 5 shows an overall schematic configuration of the fourth embodiment of the present invention. The basic operation is the same as that of the third embodiment, and different points will be described below.

  The difference from the third embodiment is that the beam splitter 14 is installed closer to the variable length dye laser device 2 than the beam expander 13, and the beam expander that spreads the laser beam 11 ′ branched by the beam splitter 14 into a sheet shape. The panda 13 'is installed. The distance between the measurement field 10 and the beam expander 13 and the distance between the cell 7 and the beam expander 13 'are made equal. The focal length of the beam expander 13 ′ is made equal to the focal length of the beam expander 13.

  With the above-described configuration, the relative positional relationship between the measurement field 10, the laser sheet light 12 that irradiates the measurement field 10, and the virtual light source 33 is set to the laser sheet light 12 ′ that irradiates the cells 7 and 7. The relative positional relationship with the light source 33 can be made equal.

  Therefore, using the intensity of the laser sheet light 12 ′ obtained in the same manner as in the first embodiment from the distribution of the fluorescence intensity of the cell 7 measured by the CCD camera 4 ′, the concentration distribution is calculated from the fluorescence intensity of the measurement field 10. Can be calculated.

  Although it is difficult to synchronize the exposure times of the CCD cameras 4 and 4 'with an error of several nanoseconds or less, the absolute values cannot be compared. However, even if the cell 7 cannot be installed near the measurement field 10, this embodiment Thus, it is possible to measure the relative concentration distribution with high accuracy in consideration of the attenuation of the laser sheet light due to the absorption of the laser sheet light by the molecule to be measured.

It is a schematic diagram which shows the 1st Embodiment of this invention. It is a schematic diagram which shows the fluorescence intensity distribution of the 1st Embodiment of this invention. It is a schematic diagram which shows the 2nd Embodiment of this invention. It is a schematic diagram which shows the 3rd Embodiment of this invention. It is a schematic diagram which shows the 4th Embodiment of this invention. It is a schematic diagram which shows the two-dimensional distribution measuring apparatus using the conventional laser beam.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Excitation pulse laser apparatus, 2 ... Wavelength variable dye laser apparatus, 3 ... Control computer, 4 ... CCD camera, 5 ... Condensing lens, 6 ... Optical filter, 7 ... Cell, 8 ... Data acquisition line, 9 ... Synchronization Line 10, measurement field 11 laser beam 12 laser beam 13 beam expander 14 beam splitter 15 mirror 16 light shielding plate 20 convex lens

Claims (8)

Laser apparatus for outputting laser beam, beam expander for converting laser beam into laser sheet light, measurement field having molecule to be measured, molecule to be measured by laser sheet light irradiated to molecule to be measured in the measurement field A two-dimensional distribution measuring apparatus having a fluorescence measuring means for measuring the fluorescence intensity of the laser, and a control device for adjusting the timing of the laser sheet light irradiation time of the laser apparatus and the measuring time of the fluorescence measuring means,
Provided between the laser device and the measurement field is a cell in which a fluorescent material is sealed and irradiated with laser sheet light, and the fluorescence emitted from the molecule to be measured in the measurement field and the fluorescent material sealed in the cell is fluorescent. Simultaneous measurement means for simultaneous measurement by the measurement means, and normalization means for normalizing the fluorescence intensity of the molecule to be measured in the measurement field using the fluorescence intensity and position information of the cell and the fluorescence intensity and position information of the measurement field A two-dimensional distribution measuring apparatus using a laser beam characterized by the above. In the two-dimensional distribution measuring apparatus using the laser beam according to claim 1,
The normalizing means obtains the characteristics of the molecule to be measured from the fluorescence intensity of the cell by the laser sheet light, calculates the intensity of the laser sheet light in the measurement field, and calculates the fluorescence intensity of the measured molecule in the laser in the measurement field. A two-dimensional distribution measuring apparatus using laser light, wherein the characteristic distribution of molecules to be measured in a measurement field is calculated by normalizing with light intensity. In the two-dimensional distribution measuring apparatus using the laser beam according to claim 2,
2. The two-dimensional distribution measuring apparatus using laser light, wherein the characteristic of the molecule to be measured in the normalizing means includes an absorption coefficient of the molecule to be measured and a proportionality constant relating to fluorescence intensity and laser sheet light intensity. In the two-dimensional distribution measuring apparatus using the laser beam according to any one of claims 1 to 3,
The two-dimensional distribution using laser light, wherein the simultaneous measurement means simultaneously measures fluorescence emitted from a molecule to be measured in the measurement field and a fluorescent substance enclosed in the cell by a single fluorescence measurement means Measuring device. In the two-dimensional distribution measuring apparatus using the laser beam according to any one of claims 1 to 3,
A beam splitter provided between the beam expander and the measurement field and for branching the sheet laser light, and branched by the beam splitter so as to be parallel to the laser sheet light that passes through the beam splitter and irradiates the measurement field. Fluorescence emitted from a mirror that reflects the laser sheet light, the cell that allows the laser light branched by the beam splitter to pass through, a molecule to be measured in the measurement field, and a fluorescent material enclosed inside the cell is a single fluorescence measurement means A two-dimensional distribution measuring apparatus using a laser beam, characterized by comprising simultaneous measuring means for simultaneously measuring by means of. In the two-dimensional distribution measuring apparatus using the laser beam according to any one of claims 1 to 3,
A beam splitter provided between the beam expander and the measurement field and for branching the sheet-like laser beam, and branched by the beam splitter so as to be parallel to the laser beam that passes through the beam splitter and irradiates the measurement field. A mirror for reflecting the laser beam, the cell through which the laser beam branched by the beam splitter passes, cell fluorescence measurement means for measuring the fluorescence intensity of the cell, the molecule to be measured in the measurement field, and the inside of the cell A two-dimensional distribution measuring apparatus using laser light, comprising: simultaneous measurement means for simultaneously measuring fluorescence emitted from the fluorescent substance enclosed in the cell by the fluorescence measurement means and the cell fluorescence measurement means. In the two-dimensional distribution measuring apparatus using the laser beam according to any one of claims 1 to 3,
A beam splitter installed between the laser device and the beam expander and branching the beam-shaped laser beam; and the beam splitter so as to be parallel to the laser beam passing through the beam splitter and irradiating the measurement field A mirror that reflects the laser light branched by the beam, a beam expander that converts the laser light reflected by the mirror into laser sheet light and irradiates the cell, and a cell fluorescence measurement means that measures the fluorescence intensity of the cell; Using a laser beam characterized by comprising simultaneous measurement means for simultaneously measuring fluorescence to be measured by a molecule to be measured in the measurement field and a fluorescent substance enclosed in the cell by the fluorescence measurement means and the cell fluorescence measurement means Two-dimensional distribution measuring device.   The two-dimensional distribution measurement apparatus using laser light according to any one of claims 1 to 7, wherein the fluorescent substance sealed in the cell is the same substance as the molecule to be measured in the measurement field. Two-dimensional distribution measuring device using laser light.

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