Abstract: A device which includes a polarizer wherein one of a pair of transmission faces of a transparent substrate by a light beam on which a polarizing separating film is not formed is formed in an inclined relationship with respect to the other transmission face of the transparent substrate on which the polarizing separating film is formed and a parallel light beam having a predetermined incident angle with respect to the polarizing separating film is passed through the polarizing separating film to effect polarized light separation. Two such devices are provided and a Faraday rotator is provided between the two devices to constitute an optical isolator.

Abstract: A ferrule having an optical fiber connected thereto and a spherical lens are fixed in a cylindrical lens holder to form a fiber collimator. The thickness of a cylindrical wall of the lens holder is made smaller at a spherical lens receiving portion than the other portion and the cylindrical lens holder is fixed to a substrate by welding. A pair of such fiber collimators are provided in an opposing relationship to each other on the substrate, and an optical function element is disposed between the opposing fiber collimators to form an optical device. By provision of a light path changing over mechanism as such optical function element, an optical switch of a small size having a high performance can be provided.

Abstract: An optical branching filter branches or mixes lights of n-kind of wavelengths. An input/output port for the light mixed n-kind of wavelengths is provided to one of two surfaces of the transparent block and second input/output parts for forming optical filters allowing only the lights having the predetermined wavelengths to pass therethrough, respectively among the lights in n-kind of wavelengths, but reflecting the lights having other wavelengths, respectively is provided to any one of two surfaces. A first input/output port and n second input/output ports, respectively is formed by an optical waveguide and a lens which optically connects the optical waveguide and first input/output part or a second input/output part. Positions of each second input/output port are selected so that the length of optical paths formed between the lenses of the first input/output port in the second input/output port are in the reverse proportion to the lengths of wavelengths corresponding to the second input/output portions.

Abstract: An optical switching means including an optical fiber moving means which is moved by an electromagnetic force, a spring body which has a guide hole through which an optical fiber passes and at least one magnetic body. The magnetic body is fixed on one of its ends and one end is arranged so as to be almost parallel with the moving optical fiber. The moving optical fiber is connected with a fixed optical fiber by moving the magnetic body with an electromagnetic force, thereby effecting optical switching with low attenuation and high accuracy.

Abstract: A panel structure is fabricated by stretching a skin plate with a tensile stress below the elastic limit stress thereof, securing this plate onto a framework with the plate under a constraining tensile stress and with portions thereof to which the constraining stress is not being fully applied being heated thereby to cause thermal expansion thereof, removing the constraining stress, and permitting the plate to cool and thereby to undergo thermal contraction and deformation, thereby producing tensile residual stress within the plate, whereby occurrence of welding deformations in the plate on the finished panel is prevented. Depending on the necessity, the skin plate may be prestretched with a stress exceeding the yield point thereof before the above described panel fabrication.