| 摘要 |
PURPOSE:To provide an optical waveguide which can be excited by a semiconductor laser of 0.81mum and can be inexpensively and easily connected to the other waveguide type part in a small type as an amplifier having a wave length area of 1.55mum and functions as a waveguide element endurable in practical use and has an amplifying action. CONSTITUTION:A Y3Al5O12 (YAG) monocrystal board or a substitutional YAG monocrystal board 1 whose yttrium is partially substituted with the other substitutable rare earth element, is used as a board to form a waveguide, and a YAG monocrystal or a substitutional YAG monocrystal in the same with a board material is used as a lower clad 2 and an upper clad 4, and in a core layer 3 to shut up light, a part of a rare earth element to constitute the board material is substituted with Nd, Tm and Lu, and a crystal whose part of Al is substituted is used according to its necessity in order to control a refractive index in a desired value. |
