Abstract: A thin film deposition method for producing an optical film with an optical characteristic on a deposition substrate in a vacuum chamber is provided. The method may include preparing in the vacuum chamber a deposition source which is a source of the film producing material; holding the deposition substrate with a substrate holding member; arranging the deposition substrate and the deposition source such that, given that a vertical distance from the center of the deposition substrate to the deposition source is defined as ZK and a horizontal distance between the deposition substrate and the deposition source as Xk, Xk/Zk is set to satisfy a following equation 0.48?Xk/Zk?0.78; rotating the deposition substrate on a rotational axis which is orthogonal to the deposition substrate; and evaporating the film producing material of the deposition source to perform deposition on the deposition substrate.

Abstract: The present invention provides a thin film deposition apparatus for producing an optical film with an optical characteristic on a deposition substrate in a vacuum chamber by depositing a film producing material on the deposition substrate, comprising:

Abstract: An arrayed waveguide grating optical multiplexer/demultiplexer is provided to suppress a temperature depending characteristic of a center wavelength. The arrayed waveguide grating comprises at least one optical input waveguide, a first slab waveguide, an arrayed waveguide, a second slab waveguide, and a plurality of optical output waveguides. The first slab waveguide is separated on an cross separating plane which is intersected to a path of light passing through the first slab waveguide to constitute separated slab waveguides. A slide moving member is provided which may move at least one of these separated slab waveguides along the cross separating plane, depending upon the temperature. A front surface side of the waveguide forming region and a rear surface side of the substrate are sandwiched by a positional shift suppressing member such as a clip. The possition depressing the waveguide forming region by the clip is escaped from the optical axis of the separated slab waveguides.