JPH065991A - Method for fabricating polymer micro ball laser - Google Patents

Abstract

PURPOSE:To prevent the generation of optical distortion on the surface of a polymer micro-ball by making monomer material and desired dyestuff coexist in advance before polymerizing the polymer micro-ball. CONSTITUTION:When forming a polymer micro-ball 1 by polymerization, dye is simultaneously put in this polymer micro-ball. Then, the dyestuff material can smoothly disperse into the micro-ball 1 without impairing the sphericity of the micro-ball. Namely, no optical strain is generated either on the surface of the micro-ball or inside the micro-ball. By this, when the micro-ball 1 is excited by a pumping light source 2 to cause laser oscillation, a threshold value at which the laser oscillation starts can be small, and also irregular reflection with respect to the total reflection that is generated inside the polymer micro- ball 1 can be prevented, thereby enhancing the efficiency of the laser oscillation. Further, since the polymerization and the process of doping the micro-ball with the dyestuff are carried out at a time, the separate process of doping the micro-ball with the dyestuff can be omitted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a polymer microsphere laser containing a dye used in a laser light emitting device.

[0002]

2. Description of the Related Art There has been reported a polymer microsphere laser in which a fluorescent dye (hereinafter simply referred to as a dye) is contained in a transparent polymer microsphere such as polystyrene as a laser light emitting element so as to perform stimulated emission of light. ing.

FIG. 2 illustrates the operating principle of such a polymer microsphere laser. When the dye 12 contained in the polymer microsphere 11 is excited by external light irradiation. The dye 12 emits light and operates as a light source.

At this time, the light 13 generated from the dye 12, that is, the fluorescence is emitted from the inside of the polymer microsphere 11 to the outside, but the dye 12 with respect to the boundary surface with the outside, that is, the tangent line L of the surface of the polymer microsphere 11. Assuming that the light 13 generated from the light is incident at an angle θ ′ (N is a vertical line) and this angle θ ′ is larger than the critical angle θ, the condition of total reflection is satisfied.
Since 3 is totally reflected and reflected inside the polymer microsphere 11, it is not emitted to the outside. However, as a prerequisite, polymer microspheres 1 of polystyrene (refractive index n1 is about 1.58) 1
The refractive index of the external medium is smaller than 1 (for example, it is made of air and the refractive index n2 is about 1.00).

That is, the light 13 generated from the dye 12
Is totally reflected inside the polymer microsphere 11, the light 13 repeats the total reflection at the boundary surface one after another and progresses as shown by the arrow, and the light 13 is confined inside the polymer microsphere 11. Become. Then, when the phase of the light originally generated matches one cycle, the next light is stimulated and emitted, and by repeating such an operation, a resonance state occurs, so that the light is amplified. , So-called laser oscillation occurs.

As described above, in the polymer microsphere laser, it is necessary to totally reflect the light 13 generated from the dye 12 inside the polymer microsphere 11 containing the dye 12 and confine it inside the polymer microsphere 11. is there.

Here, in order to incorporate the dye 12 as the laser medium into the polymer microspheres 11, for example, the polymer microspheres 11 are formed by a polymerization method, and the polymer microspheres 11 having a diameter of about 10 μm are formed by the polymerization. Prepare and treat this with the optional dye 12 in the presence of a surfactant.
Is included.

[0008]

In the conventional method for producing a polymer microsphere laser, however, there is a problem that optical distortion occurs on the surface and inside of the polymer microsphere during the process of incorporating the dye into the polymer microsphere after polymerization. There is.

When the optical strain is generated on the surface of the polymer microspheres in this way, the sphericalness of the polymer microspheres is impaired, so that diffuse reflection occurs with respect to the total reflection occurring inside the polymer microspheres. When the laser light is excited by the excitation light source to cause the laser oscillation, the threshold value for starting the laser oscillation becomes large, or the efficiency of the laser oscillation becomes low.

The present invention has been made in consideration of the above problems, and provides a method for producing a polymer microsphere laser in which an optical strain is not generated on the surface of the polymer microsphere when a dye is contained. The purpose is to do.

[0011]

In order to achieve the above object, the present invention provides a method for producing a polymer microsphere laser containing a dye for use in a laser light-emitting device, wherein a monomer material is prepared before polymerizing the polymer microspheres. And a desired dye material are allowed to coexist, the polymer microspheres are subsequently polymerized, and at the same time, the dye material is contained in the polymer microspheres.

[0012]

According to the constitution of the present invention, when the polymer microspheres are formed by the polymerization method, the dye is added to the polymer microspheres simultaneously with the polymerization of the polymer microspheres. As a result, no optical distortion occurs on the surface and inside of the polymer microspheres when the dye is contained.

[0013]

EXAMPLES A method for manufacturing a polymer microsphere laser according to the present invention will be described below.

First, a method using the emulsion polymerization method will be described. Methyl methacrylate 4 previously purified by distillation
0 g, 5 g of divinylbenzene as a cross-linking agent, 0.18 g of oxazine 1 were added to 300 ml of distilled water, 3 g of sodium dodecyl sulfate was added as an emulsifier, and the mixture was stirred for 10 minutes.

Next, 0.2 g of potassium persulfate, which is a radical polymerization initiator, was added, and 1 minute later, 0.2 g of sodium bisulfite was added. The reaction liquid thus obtained was stirred and kept at about 80 ° C. for reaction for about 5 hours. Further, methyl methacrylate, divinylbenzene and oxazine were gradually added at the above ratio to grow each polymer fine particle. This gave polymeric microspheres of the desired size.

Next, a method utilizing the suspension polymerization method will be described. Methyl methacrylate 4 previously purified by distillation
0 g, 5 g of divinylbenzene as a crosslinking agent, 0.1 g of cresyl violet and 0.1 g of azoisobutyronitrile as a radical initiator were added to distilled water, and polyvinyl alcohol was added as an appropriate amount as a dispersant.
While stirring the reaction liquid thus obtained with a mechanical stirrer, the reaction was carried out at about 80 ° C. for about 10 hours.

The reaction solution thus obtained was suction filtered, thoroughly washed with 2-propanol, and dried at about 40 ° C. for several hours to obtain polymer microspheres.

Next, when the surface and the inside of the polymer microspheres thus produced were observed with a polarization microscope under crossed Nicols, no optical distortion was observed.

Subsequently, as shown in FIG. 1, with respect to the polyethylene microspheres thus obtained as the polymer microspheres 1, an Nd ³⁺ -YAG laser was used as the excitation light source 2 to generate the second harmonics. When excited (pumped) by, the laser oscillation could be started at a threshold value of about 20 W. Reference numeral 3 is a support member for the polymer microspheres 1, 4 is a transmission medium of output light by laser oscillation generated inside the polymer microspheres 1, for example, an optical fiber, and 5 is a spectroscope connected to the transmission medium 4.

With such a structure, when the light from the excitation light source 2 is applied to the oxazine, which is a dye inside the polymer microspheres 1, the dye becomes in an excited state, and according to the operating principle described with reference to FIG. Laser oscillation occurs by causing total reflection. Then, this laser light is transmitted to the spectroscope 5 via the transmission medium 4, and the wavelength of the light is measured.

On the other hand, as a comparative example of this example, a polarizing microscope under crossed Nicols was used for polystyrene microspheres having a diameter of about 40 μm as polymer microspheres containing Rhodamine 6G as dye 2 after polymerization. As a result of observing the surface thereof, optical distortion was observed on the entire surface of the polystyrene microsphere 1. When this sample was excited by the excitation light source 2, the threshold value for starting laser oscillation was about 30 W.

As described above, according to the present embodiment, when the polymer microspheres are formed by the polymerization method, the dye is contained at the same time as the polymerization of the polymer microspheres, so that the surface and the inside of the polymer microspheres have optical strain. Does not occur. As a result, the threshold value for starting laser oscillation can be reduced, and irregular reflection of total internal reflection that occurs inside the polymer microspheres can be prevented, so that the efficiency of laser oscillation can be improved.

In the present embodiment, the optical strain does not occur on the surface and inside of the polymer microspheres as described above, because the dye is contained at the same time as the polymerization, and the sphericity of the polymer microspheres is not impaired. The pigment is contained smoothly. In addition, according to this example, the polymerization and the step of incorporating the dye are simultaneously performed, so that the step of incorporating the dye can be omitted as compared with the conventional method of incorporating the dye after the polymerization.

The polymer microspheres and dyes are not limited to those shown in the text. For example, as the polymer microspheres, polymethyl methacrylate, polycyclohexyl methacrylate, polycarbonate, polystyrene, diethylene glycol bisallyl carbonate, styrene-acrylonitrile copolymer, epoxy resin, methyl polyacrylate, polyisobutyl methacrylate, tetrabromobisphenol A , Poly (trifluoroethyl methacrylate), diallyl phthalate, poly (phenyl methacrylate),
Poly (methacrylic acid) -2,3, -dibromopropyl, poly (vinyl benzoate), poly (methacrylic acid) pentachlorophenyl, poly (methyl acrylate), poly (chlorostyrene), poly (vinylnaphthalene), poly (vinylcarbazole),
Polysilicone polymer, amorphous polyolefin, etc. can be used.

The following dyes can be used as the dye.

Examples of cyanine dyes include 3,3'-
Dimethyloxatricarbocyanine iodide, 1,
3,3,1 ', 3', 3'-hexamethylindotricarbocyanine iodide, etc.,

Examples of xanthine dyes include rhodamine 6G, rhodamine 110, rhodamine B, rhodamine 101, uranine, and the like.

Examples of oxazine dyes include cresyl violet and oxazine 1.

As the coumarin derivative, for example, 4-methylumbelliferone, orcein blue, 7-amino-4
-Methylcoumarin, etc.

Examples of quinolone derivatives include 7-diethylamino-4-methyl-2-quinolone,

Examples of the stilbene derivative include stilbene 1, stilbene 3 and the like.

Examples of the oxazole and oxadiazole dyes include 2-phenyl-5- (4-biphenylyl)
-1,3,4-oxadiazole, para-bis (5-phenyloxazol-2-yl) benzene and the like,

Examples of para-oligophenylenes include:
BM-terphenyl, para-terphenyl, polyphenyl 1 and the like.

Further, the following can be used as the crosslinking agent.

As the bifunctional crosslinking agent, for example, 1,4-butanediol dimethacrylate, 1,6-hexanediol dimethacrylate, bisphenol A dimethacrylate, etc.

As the polyfunctional crosslinking agent, for example, tris (2
-Hydroxyethyl) isocyanurate trimethacrylate, trimethylolpropane trimethacrylate, pentaerythritol tetraacrylate and the like.

[0037]

As described above, according to the present invention, the dye is contained in the polymer microspheres at the same time as the polymerization of the polymer microspheres. No optical distortion occurs in.

[Brief description of drawings]

FIG. 1 is a configuration diagram illustrating a method for exciting polymer microspheres obtained by the present invention.

FIG. 2 is an explanatory diagram of an operating principle of a polymer microsphere laser.

[Explanation of symbols]

 1 Polymer microsphere 2 Excitation light source

Claims (1)

[Claims] 1. A method for producing a polymer microsphere laser containing a dye for use in a laser light emitting device, wherein a monomer material and a desired dye material are allowed to coexist before polymerizing the polymer microsphere, and then the polymer microsphere. A method for producing a polymer microsphere laser, characterized in that a dye material is contained inside the polymer microspheres at the same time as polymerizing the polymer.