| 摘要 |
PURPOSE:To obtain the optical modulator which is easily manufactured and easy to use by giving two optical waveguides an optical path length difference which can be obtained by working, using a light source which is variable in wavelength and varying the wavelength of light, and adjusting the phase difference between light beams passed through the two optical waveguides to pi/2. CONSTITUTION:The two optical waveguides 2 and 3 are given the optical path length difference which is about tens - hundreds of times as large as the wavelength lambda of light transmitted through the optical waveguides and the wavelength of the light of the light source 5 which supplies the light to the two optical waveguides 2 and 3 is varied. Then the wavelength of the light projected by the light source 5 is adjusted to adjust the phase difference DELTAphi between the light beams transmitted through the two optical waveguides 2 and 3 freely and the center of optical modulating operation can easily be set to the position of a phase difference pi/2 where the hightest modulation sensitivity is obtained. Consequently, the manufacture is easy, the modulator can be operated invariably at the position where the modulation sensitivity is high, and a voltage to be measured can be detected with good sensitivity. |
