1992 Fiscal Year Final Research Report Summary
Ultra-Low Loss Hollow Waveguides for 5-kW Class Laser Light
| Project/Area Number |
02402036
|
|---|
| Research Category |
Grant-in-Aid for General Scientific Research (A)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
電子機器工学
|
|---|
| Research Institution | Tohoku Univ. |
|---|
Principal Investigator |
MIYAGI Mitsunobu Tohoku Univ.,Faculty of Eng.,Professor, 工学部, 教授 (90006263)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
MATSUURA Yuji Tohoku,Univ.,Faculty of Eng.,Research Asst, 工学部, 助手 (10241530)
HARA Hiraaki Tohoku Univ.,Faculty of Eng.,Asst.Prof., 工学部, 助教授 (60005296)
SAITO Mitsunori Tohoku Univ.,Faculty of Eng.,Asst.Prof., 工学部, 助教授 (60205680)
|
|---|
| Project Period (FY) |
1990 – 1992
|
| Keywords | Hollow waveguide / Dielectric-coated / IR laser / CO_2 laser / CO laser / Er:YAG laser |
|---|
| Research Abstract |
To realize delivery of high-power laser light in an infrared region,we have studied a dielectric-coated hollow waveguide. Loss reduction of the waveguide as well as improvement of output-beam quality is our main purpose. The result of this year's research is as follows. (1)CO_2,CO,and Er:YAG laser delivery by ZnS-coated Ag waveguides
We have newly adopted ZnS as a coating material for the dielectric-coated waveguide. ZnS has advantages that are the low refractive index,high durability,and non-toxicity. Fabricated ZnS-coated waveguide showed the low-loss,which is 0.25 dB/m(1 mm-bore waveguide) for the CO_2 laser light. Furthermore,it was shown that the durability of the ZnS-coated Ag waveguide is excellent. We also examined the performance for CO and Er:YAG laser. As a result,the waveguide has a good property for the both lasers. Especially for the Er:YAG laser,the waveguide endured delivering the high laser power, the pulse energy of 800 mJ and the repetition rate of 10 pps. (2)Improvement of the mandrel for fabrication of the waveguide
It is desirable that the mandrel used in the fabrication process of the waveguide has no irregularity in its shape or surface. We have newly used the Al tube coated with a polyimide film as a mandrel to satisfy the condition. The waveguide fabricated using the new mandrel showed a lower-loss and a better beam quality. Furthermore,we are investigation the glass mandrel tube as an ideal one.
|
