Abstract: An optical module is attachable to and detachable from a cage. The optical module includes a module case, a slider attached to the outside of the module case for releasing coming-off prevention from the cage, and a leakage reducing layer intervening between the module case and the slider to reduce leakage of an electromagnetic wave.

Abstract: Provided are an optical communication module which are capable of reducing a risk that an optical fiber may be detached from the optical fiber support fixture. The optical fiber support fixture includes a cylindrical body portion in which a through hole allowing an optical fiber to pass therethrough is formed. The cylindrical body portion has a circumferential surface portion in which a gap that the optical fiber crosses at a time of allowing the optical fiber to pass through the through hole is formed. The cylindrical body portion has an arbitrary point and another point on a center axis of the cylindrical body portion, the arbitrary point and the another point having different positional correspondence relationships with the gap on planes perpendicular to the center axis passing through the arbitrary point and the another point.

Abstract: There are provided an optical transmitter and a method for transmitting an optical signal, which realizes an optimum desired temperature arrival time without changing a Peltier element size, a drive current and a drive voltage, and which is stabilized by control having a sufficient phase margin. Different loop filters for heating and cooling are provided for a control loop of the Peltier element on which a laser diode is mounted, and the respective appropriate loop filters are selected and used on the basis of heating or cooling information.