| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent refractive index from varying by positioning a temperature detecting section contiguous to an electrooptic element and regulating the temperature thereof depending the detection results, thereby keeping the temperature of the electrooptic element at a constant level. SOLUTION: First, a temperature corresponding to the temperature characteristics of an electrooptic element 2 is stored at a temperature control section 4c. Since a temperature detecting section 4a is in contact with the electrooptic element 2, it has the same temperature as the electrooptic element 2. The temperature control section 4c receives a detected temperature and compares it with a preset target level in order to control the current at a temperature-regulating section 4b. The temperature-regulating section 4b generates or absorbs heat through Peltier effect and increases or decreases that temperature. Consequently, temperature of the electrooptic element 2 touching the temperature regulating section 4b increases or decreases. Temperature of the electrooptic element 2 is kept at a constant level, by repeating the current control operation thus enhancing measurement accuracy.</p> |
