Abstract: The optical module includes a main housing, a filter support component, which can affix an optical fiber, supported by a first attachment section, a light-emitting component supported by a second attachment section, a light-receiving component supported by a third attachment section, and first and second optical filters supported by a filter support component. The filter support component has a first surface and a second surface. The first optical filter is mounted on the first surface of the filter support component. The second optical filter is mounted on the second surface of the filter support component.

Abstract: The optical module includes a main housing, a light-emitting component supported by a second attachment section, a light-receiving component and a filter support member supported by a third attachment section, and first and second optical filters supported by the filter support member. The filter support member has a first surface and a second surface. The first optical filter is mounted on the first surface of the filter support member. The second optical filter is mounted on the second surface of the filter support member.

Abstract: The optical module includes a main housing to which the optical fiber can be attached and a light-emitting component and a light-receiving component attached to the main housing. At least a part of a surface of the main housing has an irregular pattern to enhance a thermal dissipation. Because at least part of the main housing comprises a heat sink, so the optical module itself has a very high heat dissipation property, eliminating the type of problems that arise when adhesive or the like is used to attach to the main housing heat sinks constituted as separate parts, such as the increase in the number of parts and the degradation in thermal conductivity to the heat sink caused by the adhesive.

Abstract: The optical module includes a main housing, a filter support component, which can affix an optical fiber, supported by a first attachment section, a light-emitting component supported by a second attachment section, a light-receiving component supported by a third attachment section, and first and second optical filters supported by a filter support component. The filter support component has a first surface and a second surface. The first optical filter is mounted on the first surface of the filter support component. The second optical filter is mounted on the second surface of the filter support component.

Abstract: The optical module includes a main housing, a light-emitting component supported by a second attachment section, a light-receiving component and a filter support member supported by a third attachment section, and first and second optical filters supported by the filter support member. The filter support member has a first surface and a second surface. The first optical filter is mounted on the first surface of the filter support member. The second optical filter is mounted on the second surface of the filter support member.

Abstract: An optical fiber terminal provided with an optical isolator having a Faraday rotator, including an optical fiber retained in a ferrule, an optical isolator element, and a permanent magnet for applying a magnetic field to the Faraday rotator is improved to provide a minimum possible outer diameter. The fiber terminal comprises an attaching member for fixedly attaching the optical isolator and the permanent magnet to the ferrule together; an air layer between an end of said optical fiber and said optical isolator element; a first outer diameter of said ferrule on the side of the optical isolator constituting a maximum diameter of the optical fiber terminal, a second outer diameter of said ferrule on the side of the optical fiber being smaller than the first maximum diameter; and the periphery of the permanent magnet being exposed to the air.

Abstract: In an optical isolator including first and second birefringent plates whose optical axes are angularly different and a Faraday rotator inserted therebetween having a Faraday rotation angle of .theta..sub.f, (1) the angles of the optical axes of the first and second birefringent plates are so set that a forward incident polarized light passes through the first and second birefringent plates both as ordinary lights or both as extraordinary lights, and the relationship .theta..sub.f +.phi..sub.eff =90.degree. is satisfied when an actually used incident polarized light is incident in an oblique direction, or (2) the angles of the optical axes of the first and second birefringent plates are so set that a forward incident polarized light passes through one of the first and second birefringent plates as an ordinary light and the other birefringent plate as an extraordinary light, and the relationship .theta..sub.f -.phi..sub.eff =0.degree. is satisfied.