| 摘要 |
<p>PURPOSE:To enable the quantitative evaluation of a thin film with high sensitivity, by simple constitution such that the damage of the thin film by the irradiation of large output energy is evaluated by measuring the propagation loss of incident guided light. CONSTITUTION:Incident beam 7 such as laser beam is guided through the specimen thin film on a glass substrate 1 through an incident coupler 3 as shown by a numeral 8 and the emitted beam 9 is received by a power metal 6 through an emitting coupler 4. At this time, the distance between the incident coupler 3 and the emitting coupler 4 is set at plural places and the power of emitted beam 9 at each position is measured to calculate the propagation loss of the guided beam 8 in the thin film 2. Next, large output laser beam 10 is allowed to irradiate the thin film 2 by a condensing lens 5 and the propagation loss of the guided beam 8 is measured by generated damage. By this method, the quantitative evaluation of the thin film is obtained with high sensitivity by simple constitution.</p> |
