JP4895534B2 - Mid-infrared light-ultraviolet light generator - Google Patents

Description

  The present invention relates to a laser apparatus that generates mid-infrared light and ultraviolet light together, and in particular, irradiates infrared light and ultraviolet light together in matrix-assisted desorption ionization time-of-flight mass spectrometry (MALDI-TOFMS). The present invention relates to a mid-infrared light-ultraviolet light generator that can be used in a method enabling mass spectrometry of insoluble protein samples.

In standard MALDI (matrix-assisted desorption ionization method), when a sample is mixed in a matrix and irradiated with ultraviolet light such as nitrogen laser light, the matrix absorbs light and converts it into thermal energy, and a small part of the matrix is converted. It takes advantage of rapid heating and vaporization with the sample.
TOFMS (time-of-flight mass spectrometry) is a velocity V determined by the energy conservation law when it is generated by a grounded grid when positive ions of various sizes are generated on a sample slide placed at a positive potential V0. Because the same potential difference V0 acts on all ions, the ions that have a smaller mass-to-charge ratio m / z perform mass analysis using the phenomenon that reaches the detector in a shorter time. It is.

  MALDI-TOFMS is a device that combines matrix-assisted desorption ionization and time-of-flight mass spectrometry, and is a simple and precise measuring device for molecular weight that is the decisive factor for protein identification. However, when UV light is used as a light source for MALDI, mass analysis is difficult when high molecular weight polymers, particularly insoluble proteins, are difficult to ionize. Thus, as reported in Non-Patent Document 1, it was found that ionization can be efficiently performed by adding an additive and using both mid-infrared light and ultraviolet light in combination.

In the method described in Non-Patent Document 1, an infrared laser beam and a matrix in which a chemical that absorbs mid-infrared light and dissolves the sample is added to the matrix to which the sample is added, and the wavelength is adjusted to the vibration mode of the additive. The sample is rapidly vaporized and ionized by simultaneously irradiating UV light absorbed by the sample. By measuring the mass of an ionized sample using a mass spectrometer, it has become possible to perform a more sensitive measurement in a high mass range that exceeds conventional measurement methods.
According to this method, it is possible to ionize and measure mass of various insoluble proteins such as proteins constituting the cell membranes of organisms and proteins that cause diseases, so that it can be expected to greatly contribute to pathological studies.

  In MALDI-TOFMS described in Non-Patent Document 1, a sample is simultaneously irradiated with ultraviolet light generated from a nitrogen laser and mid-infrared light generated from a free electron laser (FEL). Therefore, since a free electron laser apparatus that is extremely large, expensive, and difficult to handle is used, measurement cannot be performed easily. Moreover, there is a possibility that the analysis efficiency and accuracy may change by selecting the irradiation timing as well as the wavelengths of the ultraviolet light and the mid-infrared light, but it is difficult to adjust the timing because the two laser devices are independent of each other. .

Note that, as a mid-infrared light generator capable of adjusting the wavelength, the difference frequency generation between the Nd: YAG laser and the Cr: forsterite laser disclosed in Patent Document 1 can be used instead of the FEL. The wavelength tunable infrared laser device disclosed in Patent Document 1 includes a Nd: YAG laser having a wavelength of 1.064 μm and a Cr: forsterite laser capable of selecting a wavelength in the range of 1.15 to 1.35 μm to a nonlinear optical crystal. Infrared light is generated by generating a difference frequency, and the wavelength of the infrared light can be adjusted in the range of 5 to 14 μm by selecting the wavelength of the Cr: forsterite laser. Therefore, vibration excitation can be performed by selecting a suitable wavelength for any compound.
The tunable infrared laser generator described in Patent Document 1 is extremely small and can be easily operated as compared with FEL, but it is not easy to determine the irradiation timing in relation to ultraviolet light.

In addition to MALDI, there is a process for obtaining results by acting on different components included in an object by simultaneously irradiating light of different wavelengths such as infrared light and ultraviolet light.
For example, Patent Document 2 discloses a circuit in which a base material is brought into contact with an organic metal, and a metal is deposited by simultaneously irradiating an ultraviolet laser beam and a laser beam having a wavelength in a visible to infrared range. A metal deposition method for forming a pattern is disclosed.
In the disclosed method, an organometallic vapor is dissociated with an ultraviolet laser beam to deposit a metal on the substrate, and an infrared or visible laser beam having a sufficiently large intensity is used as long as the organometallic vapor does not cause significant thermal dissociation. Therefore, it is possible to deposit metal with high adhesion strength of the metal to the tail substrate and excellent thickness and pattern controllability.

In the example of Patent Document 2, a part of visible laser light having a wavelength of 514.5 nm emitted from an argon laser is converted into a second harmonic by a harmonic generator, and this is converted into an ultraviolet laser light together with the visible laser light. It is used for. As an example, a test is described in which the output of ultraviolet laser light is 100 μW, the output of visible laser light is 20 mW, and a metal such as tank stainless steel is deposited by focusing on a range of about 10 μm in diameter on the sample substrate. .
Patent Document 2 describes that various metals can be deposited using infrared light and various laser beams.
Y. Naito et al., "Matrix-assisted laser desorption / ionization of protein samples containing a denaturant at high concentration using a mid-infrared free-electron laser (MIR-FEL)", International Journal of Mass Spectrometry 241 (2005) pp .49-56 JP 2002-287190 A JP 59-208065 A

Therefore, the problem to be solved by the present invention is that it is possible to generate mid-infrared light and ultraviolet light together, and to adjust the wavelength of mid-infrared light and the timing of mid-infrared light and ultraviolet light. The present invention is to provide a compact and low-cost mid-infrared light-ultraviolet light generator that can perform the above-mentioned.
In particular, a method that enables mass spectrometry of a polymer, particularly an insoluble protein sample, by irradiating mid-infrared light and ultraviolet light together in matrix-assisted desorption ionization time-of-flight mass spectrometry (MALDI-TOFMS). It is to provide a simple mid-infrared light-ultraviolet light generator that can be used for the above.

In order to solve the above problems, a mid-infrared light-ultraviolet light generator according to the present invention includes an excitation laser device that outputs excitation laser light, a branching device disposed in the optical path of the excitation laser light, and a branching device. An infrared laser generator that obtains mid-infrared light using the branched first branched laser light as an excitation light source, and a second harmonic of the second branched laser light that is branched by the branching device and includes a harmonic generator. An ultraviolet laser generator for obtaining light is provided, and ultraviolet light and mid-infrared light are output together based on the branched laser light of the excitation laser light.
According to the apparatus of the present invention, the excitation laser supplied from the same output source is branched, the infrared light is obtained with one branched laser light, the ultraviolet light is obtained with the other, and the object is irradiated together. Therefore, an effective optical action can be generated for an object including different components that absorb and oscillate vibrations by absorbing light of different wavelengths.

The mid-infrared light-ultraviolet light generation apparatus according to the present invention is a difference-frequency generation, particularly in a tunable infrared light generation apparatus that generates mid-infrared light by generating a difference frequency between an Nd: YAG laser and a Cr: forsterite laser. A portion of the energy of the Nd: YAG laser heading toward the nonlinear optical crystal for use is branched, and this branched Nd: YAG laser and wavelength-tunable mid-infrared light can be output simultaneously.
According to the apparatus of the present invention, the difference frequency light (DFG) selected from the wavelength range of 5 to 14 μm obtained from the wavelength tunable infrared light generator and the Nd: YAG laser having a wavelength of 1.064 μm are synchronized. Therefore, it is possible to cause an effective action to an object including different components that absorb light of different wavelengths and excite vibration.

Further, a harmonic generator is provided in the optical path of the branched Nd: YAG laser so that ultraviolet light generated by the harmonic generator is generated and irradiated to the object together with the wavelength variable mid-infrared light. Good. An Nd: YAG laser having a wavelength of 1.064 μm has a second harmonic wavelength of 532 nm, a third harmonic wavelength of 355 nm, a fourth harmonic wavelength of 266 nm, and a fifth harmonic wavelength of 213 nm. It becomes ultraviolet light above 3 harmonics.
Accordingly, in the mid-infrared light-ultraviolet light generation apparatus of the present invention, if ultraviolet light of the third harmonic or higher is taken out and irradiated with the wavelength-tunable mid-infrared light DFG, a high mass such as insoluble protein is obtained. Substances can also be used in the new MALDI-TOFMS, which can easily perform mass spectrometry.

In the apparatus of the present invention, both the harmonic ultraviolet light and the mid-infrared laser light of the branched Nd: YAG laser are generated by branching the Nd: YAG laser generated by the same Nd: YAG laser generator. The emission timing of light and mid-infrared light is determined by the optical path length difference between the two.
Therefore, a delay optical path may be provided in the optical path of the branched Nd: YAG laser light or in the optical path of the mid-infrared light to adjust the optical path length difference. By adjusting the optical path length difference, it is possible to shift the timing at which the ultraviolet light and the mid-infrared light act on the corresponding components, respectively, and obtain a comprehensively good effect.

  The harmonic generator includes a first nonlinear optical element, a first dichroic mirror, a second nonlinear optical element, and a second dichroic mirror arranged in series, and can retract the second dichroic mirror from the optical path. It is preferable to configure as described above. The first nonlinear optical element generates its harmonics from the Nd: YAG laser light having a wavelength of 1.064 μm and outputs it in a state of being mixed with the original laser light. The first dichroic mirror reflects light having a wavelength of 1064 nm and transmits second harmonic light having a wavelength of 532 nm. The second non-linear optical element generates a harmonic having a wavelength of 266 nm or less from the second harmonic light and outputs it together with the second harmonic. The second dichroic mirror reflects and emits the second harmonic light to the outside of the optical path, and transmits and outputs the fourth harmonic light that is ultraviolet light.

Accordingly, ultraviolet light forms an optical path in the optical system downstream of the second dichroic mirror. Since ultraviolet light is invisible to the human eye, there is a great difficulty in positioning optical elements.
Therefore, by providing a mechanism that allows the second dichroic mirror to be inserted into and removed from the optical path and retracted from the optical path, the second harmonic that exhibits green color is emitted along with the ultraviolet light along the optical path. The green light can be used to easily position the optical element.

Furthermore, it is preferable to arrange a Brewster type Ge filter at the output position of the nonlinear optical crystal for differential frequency generation of the wavelength tunable infrared light generator.
The light emitted from the differential frequency generating nonlinear optical crystal includes Nd: YAG laser light and Cr: forsterite laser light in addition to DFG light. The Brewster Ge filter reflects about 80% of the Cr: forsterite laser and absorbs the remaining 20% and the Nd: YAG laser in the filter. By placing the Brewster Ge filter at the emission position, Only the DFG light is emitted.

Further, a visible light laser device is provided so that the visible light laser output from the visible light laser device is projected to the output side of the Brewster Ge filter so that the reflected light passes through the same optical path as the wavelength tunable infrared laser light. It is preferable to arrange.
The DFG light emitted from the wavelength tunable infrared light generator is also invisible to the human eye, which makes it difficult to arrange optical elements. If the visible light laser passes through the same optical path as that of the DFG light, the position can be adjusted via the light visible to the human eye, thereby eliminating the difficulty.

  By using the mid-infrared light-ultraviolet light generator of the present invention, a small, inexpensive, easy-to-operate matrix-assisted desorption ionization time-of-flight mass spectrometry using two types of laser light, ultraviolet light and mid-infrared light. A device (MALDI-TOFMS) can be configured. In particular, by appropriately adjusting the timing between the ultraviolet light and the mid-infrared light, it is expected that mass measurement with high efficiency and high accuracy suitable for the purpose can be performed for a high-mass material.

Hereinafter, the present invention will be described in detail based on examples with reference to the drawings.
FIG. 1 is a block diagram showing an embodiment of a mid-infrared light-ultraviolet light generator of the present invention, FIG. 2 is a conceptual diagram illustrating a mechanism for visualizing an optical path of ultraviolet light in this embodiment, and FIG. In an Example, it is a conceptual diagram explaining the mechanism which visualizes the optical path of mid-infrared light.

  In this embodiment, the mid-infrared light-ultraviolet light generation apparatus makes an Nd: YAG laser light and a tunable Cr: forsterite laser light incident on a non-linear optical crystal for generating a difference frequency to generate a desired difference frequency light (DFG). A device that divides a part of the Nd: YAG laser light in the tunable infrared light generator to be generated and passes it through a harmonic generation nonlinear optical crystal to extract ultraviolet light from the generated harmonic and emit it together with the DFG. is there.

  Referring to the specific example shown in FIG. 1, the wavelength tunable infrared light generator has a wavelength in the range of 1.17 to 1.35 μm with the pump Nd: YAG laser device 1 that generates laser light with a wavelength of 1.064 μm. Is provided with a Cr: forsterite laser device 2 and a non-linear optical crystal 3 for generating a difference frequency, and generates a difference frequency light of the Nd: YAG laser light and the Cr: forsterite laser light by the wavelength conversion action of the Nd: YAG laser light. Thus, mid-infrared light that can be selected in the range of 5.5 to 10 μm is obtained.

  The Cr: forsterite laser device 2 is an excitation light source that excites a Cr: forsterite laser unit 21 that is a tunable solid-state laser that emits laser in a wavelength range of 1.17 to 1.35 μm and a Cr: forsterite laser. An Nd: YAG laser device 22 and a pulse generator 23 for supplying a trigger to the pumping Nd: YAG laser device 22 in order to operate the Cr: forsterite laser with a pulse operation are provided.

The pulses generated by the pulse generator 23 synchronously drive two Nd: YAG laser devices, a pump Nd: YAG laser device 1 and a pumping Nd: YAG laser device 22. The pump Nd: YAG laser device 1 makes a pulse laser having a wavelength of 1.064 μm enter the difference frequency generating nonlinear optical crystal 3 as pump light. The excitation Nd: YAG laser device 22 supplies a pulse laser to the Cr: forsterite laser unit 21 as an excitation light source for the Cr: forsterite laser.
The pulse laser incident on the Cr: forsterite laser unit 21 is adjusted to have a predetermined beam diameter by a telescope composed of a lens, and then divided by a beam splitter and incident on both side surfaces of the Cr: forsterite laser crystal 24. Then both sides are excited.

The Cr: forsterite laser crystal 24 is disposed between the output mirror 27 and the reflecting mirror 26, and a spectroscopic prism 25 is provided between the laser crystal 24 and the reflecting mirror 26. The reflecting mirror 26 is a rotating mirror, and by adjusting the reflecting direction, only the selected light among the light wavelength-dispersed by the spectroscopic prism 25 returns to the output mirror 27 so that the light of the selected wavelength is a resonator. Resonate with the laser to oscillate.
The wavelength of the Cr: forsterite laser can be selected in the range of 1.15 to 1.35 μm, and is supplied to the nonlinear optical crystal 3 for generating a difference frequency as signal light.

The non-linear optical crystal 3 for generating a difference frequency is composed of a light-mixing non-linear optical crystal 31 such as an AgGaS ₂ crystal, and has a frequency ω 3 (= ω 1 −ω ₂ ) of the difference between these frequencies when laser light of frequencies ω 1 and ω 2 is input. The difference frequency light (DFG) is output.
The difference frequency light emitted from the difference frequency generating nonlinear optical crystal 3 is basically generated by the wavelength conversion action of the pump light, and the energy of the difference frequency light depends on the energy of the pump light. Further, since the frequency of the difference frequency light is the frequency difference between the pump light and the signal light, it can be adjusted by changing the frequency of the signal light.

  In the wavelength tunable infrared light generator in the present embodiment, the pump Nd: YAG laser device 1 is incident on the differential frequency generating nonlinear optical crystal 3 using a pulse laser having a wavelength of 1.064 μm as pump light, and the Cr: forsterite laser device. 2 is selected as a signal light within the wavelength range of 1.15 to 1.35 μm, and is incident on the differential optical frequency generating nonlinear optical crystal 3 in synchronization with the Nd: YAG laser. Based on this, it is possible to selectively generate mid-infrared light in the wavelength range of 5 to 14 μm.

  For example, a pulse laser having a wavelength of 1.064 μm from the pump Nd: YAG laser device 1 is used as pump light having a relatively large energy, and an output laser adjusted from the Cr: forsterite laser device 2 to a wavelength of 1.284 μm is used. When the signal light is input to the difference frequency generating nonlinear optical crystal 3, the difference frequency generating nonlinear optical crystal 3 outputs a difference frequency light having a wavelength of 6.21 μm in addition to the input laser light. These output lights are passed through the Ge filter 32 for wavelength separation, and only the long-wavelength difference frequency light (infrared light) can be extracted to the outside.

The mid-infrared light-ultraviolet light generation apparatus of this embodiment has a beam splitter 4 disposed at the output position of the pump Nd: YAG laser apparatus 1 in the above-described wavelength tunable infrared light generation apparatus, and Nd: YAG laser light. And a harmonic generator 5 is provided in the branched optical path of the Nd: YAG laser to generate harmonics of the Nd: YAG laser light.
The harmonic generator 5 is configured by using KTP, BBO, and other nonlinear optical crystals 51 and 53 and dichroic mirrors 52 and 54, and generates harmonics of incident light with the nonlinear optical crystal. Select and output the target harmonic.

FIG. 2A is a diagram showing a configuration of a harmonic generator in the present embodiment.
The harmonic generator 5 includes a first nonlinear optical crystal 51, a first dichroic mirror 52, a second nonlinear optical crystal 53, and a second dichroic mirror 54 arranged in series.
The first dichroic mirror 52 reflects light having a wavelength of 1064 nm, emits it out of the optical path, and transmits the second harmonic light having a wavelength of 532 nm. The second dichroic mirror reflects the second harmonic light, emits it out of the optical path, and transmits the fourth harmonic light having a wavelength of 266 nm.

In such a configuration, when Nd: YAG laser light having a wavelength of 1.064 μm is incident on the first nonlinear optical crystal 51, the first nonlinear optical crystal 51 generates a harmonic having a wavelength of 532 nm or less, which is lower than the second harmonic. Output in a state mixed with laser light. The first dichroic mirror 52 receives the output light of the first nonlinear optical crystal 51, emits an Nd: YAG laser beam having a wavelength of 1.064 μm to the outside of the optical path, and generates a second harmonic or lower harmonic as the second nonlinear. Incident on the optical crystal 53. The second nonlinear optical crystal 53 generates harmonics of these harmonics and enters the second dichroic mirror 54. The second dichroic mirror 54 emits the second harmonic wave exhibiting green color to the outside of the optical path, transmits the third harmonic wave or less in the ultraviolet region, and emits it along the optical path.
Since the optical path of the ultraviolet light is invisible to the human eye, positioning the optical element is very difficult.

  Therefore, in this embodiment, as shown in FIG. 2B, the second dichroic mirror 54 is configured to be retracted from the optical path. When the second dichroic mirror 54 is retracted from the optical path, the second harmonic wave exhibiting a green color is emitted along the optical path together with the ultraviolet light, so that the optical path becomes visible to human eyes and this green light is used Thus, the optical element can be easily positioned.

As shown in FIG. 3, a Brewster Ge filter can be selected as the Ge filter 32 arranged at the output position of the nonlinear optical crystal 31 in the nonlinear optical crystal 3 for generating a difference frequency of the wavelength tunable infrared light generator. .
The light emitted from the nonlinear optical crystal 31 includes Nd: YAG laser light and Cr: forsterite laser light in addition to DFG light.
The Brewster Ge filter 32 reflects about 80% of the incident Cr: forsterite laser and absorbs the remaining 20% and the Nd: YAG laser in the filter, so the Brewster Ge filter is arranged at the emission position. By doing so, only the DFG light is emitted.

Further, a visible light laser device 7 such as a He—Ne laser is provided, and the visible light laser output from the visible light laser device 7 is reflected on the output side of the Brewster Ge filter and is the same as the wavelength tunable infrared laser light. It can be made to pass through the optical path.
The DFG light emitted from the wavelength tunable infrared light generator is also invisible to the human eye, so it is difficult to arrange the optical element. However, if the visible light laser passes through the same optical path as the DFG light, The position of the optical element can be easily adjusted based on visible light.

Further, since the ultraviolet light obtained from the harmonics of the Nd: YAG laser and the mid-infrared light obtained as the difference frequency light are generated by branching the Nd: YAG laser generated by the same pump Nd: YAG laser generator 1, ultraviolet light is generated. The emission timing of light and mid-infrared light is determined by the optical path length difference between the two.
Ultraviolet light is matched to the absorption characteristics of the matrix in which the MALDI sample is mixed, and when the object to be measured is irradiated, it is absorbed by the matrix and diffuses with the sample when the matrix is rapidly vaporized by electronic excitation. Ionize with.
The mid-infrared light is adapted to the absorption characteristics of the solvent that dissolves the sample, and when irradiated on the object to be measured, it is absorbed by the solvent and excited by vibration, contributing to the isolation of the high-mass polymer that is the sample. . As described above, since ultraviolet rays and mid-infrared light act on different partners, there is a high possibility that the analysis efficiency differs depending on the mutual timing.

Therefore, as shown in FIG. 1, it is preferable to provide a delay optical path 6 in the optical path of the branched Nd: YAG laser light so that the optical path length difference can be adjusted.
By adjusting the difference in the optical path length between the ultraviolet light and the mid-infrared light, the timing at which the ultraviolet light and the mid-infrared light act on the corresponding components is shifted so that a comprehensive mass analysis can be performed.
The delay optical path may be provided in the mid-infrared light path. In addition, if the optical path is provided in both the optical path of ultraviolet light and the optical path of mid-infrared light, the adjustment range is expanded and more flexible timing selection becomes possible.

Since the mid-infrared light-ultraviolet light generator of the present invention has the above-described function, it is possible to irradiate the object to be measured with two types of laser light, that is, ultraviolet light and mid-infrared light. The matrix-assisted desorption / ionization time-of-flight mass spectrometer (MALDI-TOFMS) can be configured that is small, inexpensive, and easy to operate. In particular, by appropriately adjusting the timing between the ultraviolet light and the mid-infrared light, it is expected that high-mass materials can be measured with high efficiency and high accuracy.
It should be noted that the mid-infrared light-ultraviolet light generator of the embodiment is an example as the best mode for carrying out the invention, and needless to say, means for solving the problem is not limited thereto. Yes.

It is a block diagram showing one Example of the mid-infrared light-ultraviolet light generator of this invention. It is a conceptual diagram explaining the mechanism which visualizes the optical path of the ultraviolet light in a present Example. It is a conceptual diagram explaining the mechanism which visualizes the optical path of the mid-infrared light in a present Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Nd: YAG laser apparatus for pumps 2 Cr: forsterite laser apparatus 21 Cr: forsterite laser part 22 Nd: YAG laser apparatus for excitation 23 Pulse generator 24 Cr: forsterite laser crystal 25 Spectral prism 26 Reflector 27 Output mirror 3 Difference frequency Nonlinear optical crystal for generation 31 Nonlinear optical crystal 32 Ge filter 4 Beam splitter 5 Harmonic generator 51 First nonlinear optical crystal 52 First dichroic mirror 53 Second nonlinear optical crystal 54 Second dichroic mirror 6 Delayed optical path 7 Visible light laser device

Claims (7)

A mid-infrared light-ultraviolet light generator applicable to a mass spectrometer that performs mass spectrometry by irradiating a test object with ultraviolet light and mid-infrared light,
An excitation laser device that outputs excitation laser light;
A branching device disposed in the optical path of the excitation laser light;
An infrared laser generator for obtaining mid-infrared light using the first branched laser beam branched by the branching device as an excitation light source;
An ultraviolet laser generator that includes a harmonic generator and obtains ultraviolet light from the harmonics of the second branched laser beam branched by the splitter ;
Provided in the optical path of at least one of the mid-infrared light and the ultraviolet light, and changing the optical path length difference between the mid-infrared light and the ultraviolet light to change the mid-infrared light and the ultraviolet light with respect to the test object A delay optical path for adjusting the irradiation timing of light,
Mid-infrared light-ultraviolet light generator.   The pump laser device is a Nd: YAG laser generator that outputs Nd: YAG laser light, and the infrared laser generator includes a Cr: forsterite laser and a nonlinear optical crystal, and the Nd: YAG laser light and the A tunable laser beam output from a Cr: forsterite laser is incident on the nonlinear optical crystal and mixed to obtain mid-infrared light by generating a difference frequency. The ultraviolet laser generator further includes the second branch laser. 2. The mid-infrared light-ultraviolet light generator according to claim 1, wherein a harmonic generator provided in an optical path of the light outputs the harmonics of the second branched laser light as ultraviolet light. 3. The mid-infrared light-ultraviolet light generator according to claim 1, wherein the harmonic generator generates a harmonic light of incident light using a nonlinear optical element. The harmonic generator includes a first nonlinear optical element, a first dichroic mirror, a second nonlinear optical element, and visible light out of light incident from the second nonlinear optical element, which are arranged in series . A second dichroic mirror that reflects light and transmits ultraviolet light ;
Moreover, mid-infrared light according to any one of claims 1 to 3, characterized in that it comprises a mechanism for outputting the visible light and the ultraviolet light by Rukoto is retracted said second dichroic mirror from the optical path An ultraviolet light generator; Mid-infrared light according to any one of claims 3 and 4 quoting claims 2 and 2, characterized in that a Brewster-type Ge filter at the output position of the nonlinear optical crystal An ultraviolet light generator; The tunable infrared laser generator is provided with a visible light laser device, the visible light laser output from the visible light laser device is reflected on the output side of the Brewster Ge filter, and the visible light laser 6. The mid-infrared light-ultraviolet light generator according to claim 5 , wherein the mid-infrared light-ultraviolet light generator is disposed so as to pass through the same optical path as that of the variable laser light. Mid-infrared light according to any one of claims 1 6 - Matrix Assisted characterized by mass infrared light and ultraviolet light is irradiated to the specimen analysis among generated by the ultraviolet light generator Desorption ionization time-of-flight mass spectrometer.

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