JPS61151039A - Quartz laser glass - Google Patents

Abstract

PURPOSE:To provide a quartz laser glass composed of Eu2O3, Er2O3, Sm2O3, Al2O3, P2O5 and SiO2, and having smaller nonlinear refractive index, heat- expansion coefficient and heat-conductivity than the conventional laser glass, high ultraviolet transmittance and excellent water-resistance. CONSTITUTION:The objective quartz laser glass is produced from a composition composed of 0.5-10(wt)% Eu2O3, 0.2-10% Er2O3, 0.2-10% Sm2O3 (Er2O3+Sm2 O3=0.2-10%), 1-20% Al2O3, 1-20% P2O5 (Al2O3+P2O5=1-20%) and the remaining part of SiO2.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to quartz laser glass, and more particularly to quartz laser glass, which has excellent features not found in conventional laser glasses.

<Prior art> Since self-focusing is determined by the nonlinear refractive index of the laser glass, the smaller the laser glass, the higher the output power. However, conventional silicate-based and phosphate-based laser glasses cannot be used at ultra-high power because the laser beam self-focuses within the laser glass.

<Problems to be solved by the invention> The nonlinear refractive index, thermal expansion coefficient, and thermal conductivity are significantly lower than those of conventional silicate-based and phosphate-based laser glasses, and the ultraviolet transmittance is large, and The purpose is to provide laser glass with excellent water resistance.

Means for Solving the Problems The inventors of the present invention conducted various studies in search of the above-mentioned objective laser glass, and found that a quartz laser glass having the following composition has the following features.

(Composition of quartz laser glass of the present invention) In weight%, E
u, Os: 0.5-10t Eraoi; 0.
2~lOs Sm, O,; 0.2~10. E r, O
.

+Sm, O,: 0.2~Lot A1. O,; 1-2
0°P, O,; 1-20. At, ○z+”PxOs;
Quartz laser glass consisting of 1-20° remaining SiO□.

(Features of the quartz laser glass of the present invention) (1) Approximately 1/3 of each of conventional silicate-based and phosphate-based laser glasses
．． 3 with the same size and a nonlinear refractive index of 1/2,
It can generate twice as much power.

(2) Since the coefficient of thermal expansion is 1720 or less than that of conventional laser glass, it can be used stably with little change in optical path length.

(3) Since the thermal conductivity is about twice as high as that of conventional laser glass, it has good cooling efficiency and can be reused about twice as often.

(4) Unlike conventional laser glasses, this quartz laser glass can effectively use optical absorption in the ultraviolet region, increasing excitation efficiency.

(5) Since our quartz laser glass does not undergo solarization, there is no need for protection against ultraviolet rays.

(6) Our quartz laser glass has good water resistance, and the polished surface is hard to burn and is optically stable.

(7) This quartz laser glass has good optical homogeneity and is extremely unlikely to be damaged by laser.

(8) Since the oscillation wavelength of this quartz laser glass is 0.55μ, fluorescence in the visible and ultraviolet regions can be used.

(9) Since ultraviolet light can be easily generated with double harmonics, it can be expected to be used in laser CVD and laser annealing.

(10) The above-mentioned properties of the quartz laser glass are described in numerical terms as follows.

Nonlinear refractive index 0.6 x 10''''13esu Coefficient of thermal expansion 5-10 x 10-7/'C Thermal conductivity 0.
030~0, 035 cal/cm sec'c Water resistance (wt 1oss%) (H, 0100℃l h) 0
．． 000 or less Ultraviolet transmittance 50% or less (10m/
m 200n+n) Homogeneity 4x10″″
S or less.

<Function> In the quartz laser glass, Eu, O, are Eu3+
The ions act as light-emitting ions for lasers, and the preferred concentration of Eu, O, is 0.5 to 10%. If it exceeds 10%, concentration quenching occurs and is not practical.

Er, O, Sm, O, serve as laser sensitizing ions as Er'' and Sm3+, respectively, and are added singly or in combination.

This preferred concentration range is Er, 03 ° 0.2 to 10 wt%.

Sm2O3, 0.2-10 wt%.

Er, O, +Sm, ○; 0.2 to 10 wt%.

It is.

A1○ and P2O5 work to introduce luminescent ions or sensitizing ions such as Eu3+ into the 5i-O network structure of the matrix quartz glass and exhibit effective fluorescent properties. A range of 20 wt% is preferred.

The quartz laser glass having the above composition range exhibits the following characteristics.

0 Laser characteristics Eu, ○, (wt%) 0.5~g Stimulated emission cross section 'a p (10-"c+++")
2.2-5 Fluorescence lifetime (μ5ec) 25
0-400 oscillation wavelength (μm) 0.5
5 Attenuation coefficient (0,55u) (m-1) 0.
1 or less 0 laser damage threshold (l n5ec pulse) (J
/cm") (0,55μ) Surface damage 20-25 Internal damage 30-400 Optical properties Nonlinear refractive index n, (X 10-"esu)0.6 Refractive index n (0,55) 1.460-1 .48
0 Atsube number (νd) 68 Brewster angle 55'33'~55'
54' Linear expansion coefficient (10''''@/'C) 0.5
~0.9 Temperature coefficient of refractive index (0-100℃) 1.0x
l0. Temperature change in optical path length (10'''!/'C)
5.0-5.40 Thermal properties Thermal conductivity (25℃) (cal/c+w sec'c)
0.030-0.0350 Chemical properties Water resistance (wt 1oss%) (8,0100℃lh)
0.000 or less Knoop hardness 100g) (IKgf/am”)
590-620 Manufacturing method To manufacture the quartz laser glass of the present invention, basically flame oxidation decomposition and melting (Flame oxidation decomposition and melting) is used.
ydr.

-1ysis Method or Sootsimpregnation Method
d) is used.

Flame oxidative decomposition melting is a method in which a compound of the components constituting quartz laser glass is added directly into a high-temperature oxidizing flame, such as the Bertai method and the high-frequency oxygen plasma method.

For example, vapors of halides of each element constituting quartz laser glass are introduced into an oxygen plasma flame. A low boiling point halogenated compound, such as silicon tetrachloride (Sil14) p as a 5i08 (silica) source, phosphorus oxychloride (POCl2) as an os source, is introduced together with argon (Ar) as a carrier gas, and a high boiling point halogenated compound AI
CI), EuCl, E rC1, and SmC1 are heated to a high temperature and have a high vapor pressure, and are introduced into the flame in predetermined amounts individually or as a mixture.

As an alternative method to the above methods, there is a CVD method (VAD method as a modified method) which is also used for manufacturing optical fibers. Hydrolyzed soot-like oxides of silicon halides are deposited on a support in an oxyhydrogen flame at low temperatures.

The pores of this soot-like silica deposit are impregnated with an alcoholic solution of the halide of the added element at room temperature, and after removing the dry alcohol, heated to a high temperature of 14.00°C or higher, He, C1
□EuC1, by heating in an atmosphere and hanging a transparent quartz glass body, or by heating this soot-like silica deposit at a temperature of 1000°C to 1300°C.

After converting ErC1, SmC1, or AlCl into vapor and allowing oxygen gas to enter the pores as an oxide as a carrier gas, He, C1□ at a high temperature of 1400°C or higher
A transparent quartz glass body may be heated in an atmosphere. In addition, in the sol-gel method, an alkoxide solution of an additive element or an inorganic or organic compound is introduced into a dispersion colloidal sol of silicon alkoxide solution or its hydrolyzed product, silica gel, or a flame-decomposed oxide of silicon halide (e.g. fumed silica). Carefully heat the mixed gel to over 1000℃,
If necessary, a He-CI□ treatment may be performed to form a quartz glass body, which can be applied to the production of quartz laser glass.

Effect〉 The quartz laser glass of the present invention is a conventional silicate-based glass.

The nonlinear refractive index is approximately 173 to 1/2 that of phosphate-based laser glasses, so with the same size, 3 to 2 times higher output can be obtained, and the coefficient of thermal expansion is approximately 1 of that of conventional laser glasses. /20 or less, so it can be used stably with little change in optical path length, and its thermal conductivity is about 2 that of conventional laser glass.
Since it is twice as large, it has good cooling efficiency and can obtain about twice as many repetitions, can effectively use optical absorption in the ultraviolet region and increase excitation efficiency, and since there is no solarization, there is no need to protect against ultraviolet rays. Furthermore, it has good water resistance, is hard to burn on the polished surface, and is optically stable.
Furthermore, it has good optical homogeneity and is extremely less likely to be damaged by laser.

The quartz laser glass of the present invention has the essential structure (X-ray reflection image, infrared absorption image, etc.) of quartz glass, physical
Retains chemical, thermal and optical properties well.

Glass has been found to have the above-mentioned characteristics and can fulfill the above-mentioned purpose.

Claims (1)

[Claims] In weight%, Eu_2O_3; 0.5-10, Er_2O
_3; 0.2-10, Sm_2O_3; 0.2-10,
Er_2O_3+Sm_2O_3; 0.2-10, Al
_2O_3; 1-20, P_2O_5; 1-20, Al
_2O_3+P_2O_5; 1 to 20, the rest is SiO_
Quartz laser glass consisting of 2