| 摘要 |
PURPOSE:To exactly diffract a light beam, and to miniaturize the titled waveguide, and also, to make it have a high performance by placing one layer or more of gap layers whose surface is vertical to an optical propagation axis and whose width in the optical propagation axis direction is (d), in a part in the optical propagation direction of a core by interposing a core layer whose thickness in the optical propagation axis direction is (h), so that width of the gap layer and thickness of the core satisfy a specific relation. CONSTITUTION:When a refractive index of a core 4, a refractive index of a gap layer 8, a wavelength of light, an incident angle of light to the gap layer 8, and an angle of refraction are denoted as n1, (n), lambda, theta0, and theta, respectively, conditions of equations I and II are satisfied, with regard to width (d) and (h) of the gap layer 8 and a core layer 9. In the expressions, (l) and (m) are integers. As for a fundamental material for constituting a functional optical waveguide, it is desirable to use a quartz glass optical waveguide, and it can be manufactured by performing a minute working. In this way, variable function devices being small in size and having a high performance are obtained, and also, a reflecting layer having a high performance can be provided on an optional place of the optical waveguide. |
