JPH05319856A - 0.55mum emission ho fluoride laser glass sensitized with yb - Google Patents

Abstract

PURPOSE:To provide a green light emitting laser glass having large green light emission intensity and containing fluorine which gives high up-conversion efficiency. CONSTITUTION:The fluoride glass contains 5-16cat% Yb<3+> and 0.03-1cat% Ho<3+>. This laser glass contains cations except for Yb and Ho, for example, Zr, Hf, Al, Mg, Ca, Sr Ba, etc., and at least fluorine as anion. When this glass is irradiated with 0.98mum wavelength semiconductor laser light, the glass produces 0.55mum wavelength green laser light.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a Ho fluoride laser glass which emits a Yb-sensitized 0.55 μm laser.

[0002]

2. Description of the Related Art Conventionally, a laser diode (LD) having a wavelength near 0.98 μm excites Er ions (E
A glass of green light having a wavelength of 0.55 μm sensitized by Yb ³⁺ with r ³⁺ ) as an emission center is known. The Yb ion in this glass absorbs infrared light and is excited to a higher energy state, the Er ion is excited by this higher energy, and the excited Er ion undergoes luminescence transition to generate a shorter wavelength light than the excitation light. Emits light. This phenomenon is called the up-conversion phenomenon.

As one of applications of the up-conversion phenomenon, a material which causes the up-conversion phenomenon can be used as a display material by irradiating infrared light to emit green light only at the irradiated portion. When used as such a display material, it is necessary that the emission intensity of green light is high. Further, if the emission intensity of green light is increased, this material itself can be used as a light emission source of green laser.

[0004]

However, green light due to Er ions is not sufficient to operate as a laser.

Therefore, an object of the present invention is to provide a green light emitting laser glass which has a high upconversion efficiency and contains fluorine and which has a high green light emission intensity.

[0006]

The present invention provides Yb ³⁺ of 5 to 5
The present invention relates to a fluoride laser glass containing 16 cat% and Ho3 ⁺ of 0.03 to 1 cat%.
In the present specification, cat% means cation% (cationic%).

The light emission mechanism of the fluoride glass containing Yb ³⁺ and Ho ³⁺ of the present invention will be described. In Figure 1, Yb ³⁺
And the energy level diagram of Ho ³⁺ are shown. The emission at 0.55 μm is caused by the ground transition of Ho ³⁺ from ⁵ S ₂ to ⁵ I ₈ . When 0.97 μm of LD is irradiated, Yb ³⁺ is excited from the ground state ² F _7/2 to ² F _5/2, and the excited energy of Yb ³⁺ is transited to Ho ^{3+ 5} I ₆ . .. ⁵ I ₆ Ho
^{It is considered that the 3+} ion is excited by ⁵ S ₂ ( ⁵ F ₄ ) with the energy of 0.98 μm of Yb ³⁺ and emits 0.55 μm when moving from this level to the ground state.

Ho ions, which act as the emission center of green light, have an amount of 0.03 cat, as shown in FIG.
If it is less than%, sufficient emission intensity cannot be obtained, and if it exceeds 1%, the emission intensity decreases. Therefore, Ho ³⁺ is 0.03-1
Limited to cat%. On the other hand, Yb ions have a function of sensitizing green light emission due to Ho ions, but as shown in FIG. 3, if the amount is less than 5 cat%, a sufficient sensitizing effect cannot be obtained, and if it exceeds 16 cat%, the sensitization is increased. The feeling effect decreases. Therefore, Yb ³⁺ is limited to 5 to 16 cat%.

The laser glass of the present invention contains, in addition to Yb ions and Ho ions, Zr ions, Hf ions, Al ions, Mg ions, Ca ions, Sr ions and Ba ions as cations constituting the glass. ,
The ratio of each ion in the above cations is expressed in mol%, and Zr
The total amount of ions and Hf ions is 1 to 25%, the amount of Al ions is 20 to 45%, the total amount of Ma ions, Ca ions, Sr ions and Ba ions is 20 to 70%, and the glass is formed. As an anion, at least F ion is contained, and the ratio of F ion in the anion is from 80 to 80 in mol%
It can be 100% fluoride glass.

As cations other than Yb ions and Ho ions, Zr ions, Hf ions, Al ions, Mg ions, Ca ions, Sra ions, and Ba ions can be used. Of these, Zr ions, Hf ions, and Al ions are components that form the glass skeleton,
These amounts are preferable because they increase the stability of the glass against crystallization within the above limits. Further, Mg ion, Ca ion, Sr ion, and Ba ion are glass modifying components, and the amounts thereof are preferable because the stability against crystallization of glass is improved and the chemical durability is improved within the above limits.

Further, alkali metal ions such as Li ion, Na ion, K ion and Cs ion, Y ion, S
c ion, Gd ion, Zn ion, Pb ion, Cd
Ions, In ions, Ga ions and the like enhance the stability of the glass against crystallization and can be used as the cation component of the glass. If the amount of the alkali metal ion is large, the chemical durability of the glass is deteriorated, so 20 mol% or less is preferable, and the amount of Y ion, Sc ion, Gd ion, Zn ion, Pb ion, and Cd ion is large. On the contrary, since the stability of the glass against crystallization is deteriorated, 20 mol% or less is preferable, and Sc ion, In ion, and Ga ion are also preferably 5 mol% or less.

Next, the anion will be described. F ions are the basic component of glass. Further, Cl ions, Br ions, and I ions can be contained by substituting with F ions. The amount is 20% for Cl ions, Br
If the content of each of the ions and I ions exceeds 10%, the glass tends to crystallize and the chemical durability decreases,
Cl ions are limited to 0 to 20 mol%, Br ions to 0 to 10 mol%, and I ions to 0 to 10 mol%. If the amount of F ions is less than 80%, it becomes difficult to obtain a glass having high stability against crystallization.
The total amount of r ions and I ions is limited to 20 mol% or less.

The laser glass of the present invention can be obtained by heating and melting a glass raw material containing HoF ₃ , YbF _{3 and the} like prepared by mixing so as to have a predetermined composition, followed by cooling.

The laser glass of the present invention is 0.97 μm
0.55 μm by irradiating the semiconductor laser of
Gives a green laser light.

[0015]

The present invention will be described in more detail with reference to the following examples. (Example 1) ZrF ₄ , AlF ₃ and Mg as starting materials
F ₂ , CaF ₂ , SrF ₂ , YF ₃ , NaF, Ho
Using F ₃ and YbF ₃ , the cation component constituting the glass finally obtained is expressed in mol% and Zr ion is 12.8.
%, Al ion 25.1%, Mg ion 3.7%, Ca
Ion 15.4%, Sr ion 13.6%, Y ion 1.0%, Na ion 5.6%, Yb ion 12%, H
O ion 0.1% and anion component is mol% display F
Batches were obtained by weighing and mixing so that the ions were 100%.

Next, the obtained batch is placed in a crucible made of carbon and placed in a heating furnace, and the above batch is heated and melted at 950 ° C. for 45 minutes under this atmosphere while supplying argon gas into the furnace. Then, a glass melt was obtained. Then, the obtained glass melt was rapidly cooled and then cooled as it was to obtain fluoroalumino zirconate glass (AZF).

Example 2 Yb ³⁺ was ^added to 19 in AZF.
The raw materials were weighed and mixed so that the ratio was fixed to cat% and the amount of Ho ^{3+ was changed to} the amount shown in FIG. 2, and glass was obtained in the same manner as in Example 1.

(Example 3) In AZF, the amount of Ho ³⁺ was fixed at 0.1 cat% and the raw materials were weighed and mixed so that the amount of Yb ³⁺ was varied to the amount shown in FIG. Example 1
A glass was obtained in the same manner as in.

Comparative Example 1 A glass containing no Yb ion in the glass composition of Example 1 was obtained in the same manner as in Example 1.

(Measurement of Emission Spectra) Examples 1 and 2,
After cutting the glass of Example 3 and Comparative Example 1 and polishing the six sides, the emission spectrum was measured when these glasses were excited by a semiconductor laser having an oscillation wavelength of 0.98 μm.

Since the absorption amount of the excitation light increases in proportion to the Yb ion concentration, the green emission intensity at a wavelength of 0.55 μm is standardized by the absorption amount of the excitation light, and only the Ho ions are added to Yb.
The emission intensity of the glass containing no ions (Comparative Example 1) was 1
Then, the relative intensity was calculated for Example 1, Example 2 and Example 3. The results are shown in FIGS.

It can be seen from FIG. 2 that the emission intensity is remarkably high in the range of Ho ³⁺ of 0.03 to 1 cat%. Further, it can be seen from FIG. 3 that the emission intensity is remarkably high when Yb ³⁺ is 5 to 16 cat%.

[0023]

According to the present invention, in a glass containing fluorine as an anion, Yb ions and Ho as cations are added.
Since it contains ions at the same time, a laser glass having a large emission intensity of green light having a wavelength of 0.55 μm can be obtained. Therefore, the laser glass of the present invention can be preferably used as a green laser light source and the like.

[Brief description of drawings]

FIG. 1 is an energy level diagram of Yb ³⁺ and Ho ²⁺ .

FIG. 2 shows the relationship between Ho ion concentration and emission intensity.

FIG. 3 shows the relationship between Yb ion concentration and emission intensity.

Claims (2)

[Claims] 1. A fluoride laser glass containing 5 to 16 cat% of Yb ³⁺ and 0.03 to 1 cat% of Ho ³⁺ . 2. Zr is used as a cation constituting glass.
Ions, Hf ions, Al ions, Mg ions, Ca ions, Sr ions, Ba ions, Yb ions and Ho ions, and the ratio of each ion in the cations is mol%.
The total amount of Zr ions and Hf ions is 1 to 25 on the display.
%, Al ions are 20 to 45%, the total amount of Mg ions, Ca ions, Sr ions and Ba ions is 20 to 70%,
Yb ions 5 to 16%, Ho ions 0.03 to 1%
And at least F ions as anions forming the glass, and the proportion of F ions in the anions is 80 to 100% in terms of mol%.