JPS58200213A - Laser irradiating device of multiple optical path - Google Patents

Abstract

PURPOSE:To resolve the lowness of the yield of reaction and the efficiency of energy use, by dividing a laser light into two or more and allowing respective laser lights to cross on an object to be irradiated after they pass the same optical path length. CONSTITUTION:A laser light 208 oscillated from a laser oscillator 201 is divided into two by a semitransparent mirror 202, and respective laser lights have optical paths changed by total-reflective mirrors 203 and 204 so that they cross on a gass cell 207. Laser lights are condensed in optical systems 203 and 204 if required and are made into parallel lights, and a sample in the gass cell is irradiated with these lights from window plates 305 and 306. Laser lights cross in the center of the gas cell to form a high energy area 306 and are totally reflected on specular walls of the gass cell and cross again in the center of the gas cell to form a high energy window area 307. Laser lights form several high energy areas in this manner and are discharged to the outside of the gass cell from a window plate 304.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical field to which the invention pertains] The present invention relates to a multi-optical laser irradiation device for irradiating laser light when causing a reaction using laser light.

[Prior art and its problems]

Conventionally, a laser beam emitted from a laser oscillator is adjusted in diameter and condensing rate using lenses, mirrors, etc., and is irradiated onto a sample placed in an irradiation cell.

Now, if the laser output is L (J), and the diameter of the laser beam is reduced to S (.i) using a lens or mirror, the energy density of the laser beam becomes L/19 (J/d). At this time, if the upper limit of the energy density of radar light that does not damage the lens or window plate material is P (J/d), it must be considered that P > L/S at all times for the lens or window plate. If this relationship is violated, the lens or window plate will be damaged. Therefore, when a high energy density laser beam is required, the lens 101 and the window plate 1 in Figure @1 are explained based on the drawings.
At 02.103, the laser beam 105 is injected into the irradiation cell 104 to obtain a desired energy density by using the lens 101 while taking into consideration that the energy density does not exceed the allowable energy density. However, when the sample is a liquid or gas, the only sample that is effectively irradiated by the radar light is the one that exists within the diagonally shaded high energy density region 106 in the irradiation cell, which reduces the efficiency of the reaction. , which is extremely poor, and also causes a considerable density distribution within the region 106, which has the disadvantage that irradiation cannot be performed under uniform energy density. Also, despite the presence of high-power laser oscillators at hand,
There may also be cases where the laser output is temporarily lowered to protect the lens or window plate, and then irradiation is performed, which is an inefficient operation.

[Purpose of the invention]

An object of the present invention is to provide a laser irradiation device that eliminates the poor reaction yield and energy utilization efficiency of conventional devices without damaging optical components such as lenses and window plates.

[Summary of the invention]

The present invention uses laser light oscillated by a laser oscillator,
This is a multi-path laser irradiation device that divides the laser beam into two or more beams, passes the same optical path length, and then crosses each other again at the irradiated object.

This is a multi-path laser irradiation device configured with high re-energy density.

[Embodiments of the invention]

The present invention will be explained based on the drawings regarding the case where a sample in a gas cell is irradiated. In Fig. 2, 201
is a single laser generator that emits extremely high-resolution laser light. 202 is a semi-transparent mirror for laser oscillation d20
The laser beam 208 oscillated in step 1 is divided. 203 and 204 are total reflection mirrors, and 205 and 206 are combinations of lenses, mirrors, etc., which narrow down or collimate the laser beam. 207 is an irradiation gas cell. The optical path length is exactly the same when passing through the total reflection mirror 204 or 205.

To explain the irradiation gas cell 207 in more detail, the third
In the figure, 301 is an irradiation gas cell body whose inner surface is mirror-finished and totally reflects the laser beam.

302, 303 and 304 are window plates, and depending on the type of laser, materials with low absorption at the laser wavelength are used. 305 and 306 are Rayleigh'-lights collected at 205 and 206 in FIG.
1. In Figures 2 and 3, the number of divisions of the laser beam is two to avoid complexity, but the actual number of divisions depends on the energy density required within the gas cell and the lens. It is determined by taking into account the allowable energy density of the window panels, etc.

In the laser irradiation device configured as described above, the laser beam 208 emitted from the laser oscillator 201 is split into two parts by the semi-transparent mirror 202K, and then sent to the gas cell 2 again by the total reflection mirrors 203 and 204, respectively.
The button light paths are changed so that they intersect at 07. If necessary, the radar light is condensed in the optical systems 205 and 206, and further converted into parallel light, which is then applied to the window plates 305 and 3.
From 06 onwards, the fitting in the gas cell is irradiated. The laser beams first intersect at the center of the gas cell and form a region 3 with high energy density.
06, and then is totally reflected on the mirror-like gas cell wall and returns to the center of the gas cell, intersecting to form a high energy density region 307. After repeating this several times, the laser beam exits the gas cell through the window plate 304.

Furthermore, the ratio of the high energy density region to the gas cell increases as the number of reflections of the V-boo light within the gas cell increases. The number of reflections of the laser beam is determined by the incident angle θ of the laser beam on the gas cell, so the total reflection mirror 2
By adjusting the angle with respect to the optical axis of 03 and 204, or in the optical system of 205 and 206,
By setting the incident angle θ, the ratio of the high energy density region to the gas cell can be adjusted.

In addition, if there is a possibility that a portion of the window plate 304 that exceeds the allowable energy density may be formed, as shown in FIG.
This fear can be avoided by providing window plates 404 and 405 to guide the laser beam to the outside of the gas cell.

〔Effect of the invention〕

The laser irradiation device configured in this way can increase the proportion of the high energy density region within the irradiation gas cell without disturbing optical parts such as lenses and window plates, and can evenly overlap the laser beams. Because of the combination, it is possible to obtain a uniform high energy density distribution, which has the effect of causing a large amount of sample gas to react in a uniform process compared to the conventional method.

[Brief explanation of drawings]

Figure 1 is an explanatory diagram showing an example of conventional radar irradiation;
The figure is a schematic diagram of a radar irradiation device according to the present invention, and FIG.
Detailed view of the irradiation gas cell shown in Figure 2, Figure 44
It is a detailed diagram of the performance of the irradiation gas cell shown in the south. 101... Lens, 102... Window plate, 103...
Window plate, 104... Irradiation cell, 105... Radar light, 106... High energy density region, 201... Laser oscillator, 202... Semi-transparent mirror, 203... Total reflection mirror, 204... Total reflection mirror, 205. 206... Combination of lens and mirror, etc., 207... Gas cell for irradiation, 301... Gas cell body for irradiation, 302, 303, 304... window board,
305, 306...Rage 1-light, 307.308
,309...n...high energy density region, 4
01...Irradiation gas cell body, 402.403,404,405...Window plate, 406,
407...Laser light, 408, 409...n'
-1, n'...High energy density region. IWJ Figure 2

Claims (2)

[Claims] (1) A multi-optical laser irradiation device characterized in that a laser beam emitted from a laser oscillator is divided into two or more beams, and each laser beam is made to intersect at an irradiated object again after passing through the same optical path length. (2) The multi-optical laser irradiation device according to claim 1, characterized in that the luminous flux of the divided relay beam is narrowed down to increase the energy density.