Abstract: An optical module has plural optical units each having an optical communication device that performs conversion between an electrical signal and an optical signal, and a socket that the optical communication device is fitted in. The optical units are aligned and detachably connected to each other by a part of the socket in contact with the socket of the adjacent optical unit.

Abstract: A multi-chip module having an optical element sending and receiving optical signals and mounted on a printed circuit board in which an optical guide is formed, includes an optical path-converting member that protrudes from a face of the multi-chip module that is to be connected to the printed circuit board, is optically connected to the optical element, and is inserted into an inserting hole formed on the printed circuit board so as to intersect the optical guide when mounting the multi-chip module. The optical path-converting member is inserted into the inserting hole to form an optical path guiding light from the optical element into the optical guide or guiding light transmitted through the optical guide into the optical element.

Abstract: An optical module has plural optical units each having an optical communication device that performs conversion between an electrical signal and an optical signal, and a socket that the optical communication device is fitted in. The optical units are aligned and detachably connected to each other by a part of the socket in contact with the socket of the adjacent optical unit.

Abstract: A data link module includes: a cable comprising an electric wire and optical fibers aligned with each other; a substrate disposed at one end of the cable; signal medium conversion elements performing conversion between an electric signal and an optical signal; an electric terminal that is electrically connected to the electric wire of the cable; and an electric connector that is electrically connected to the signal medium conversion elements and the electric terminal respectively.

Abstract: A multi-chip module having an optical element sending and receiving optical signals and mounted on a printed circuit board in which an optical guide is formed, includes an optical path-converting member that protrudes from a face of the multi-chip module that is to be connected to the printed circuit board, is optically connected to the optical element, and is inserted into an inserting hole formed on the printed circuit board so as to intersect the optical guide when mounting the multi-chip module. The optical path-converting member is inserted into the inserting hole to form an optical path guiding light from the optical element into the optical guide or guiding light transmitted through the optical guide into the optical element.

Abstract: Ink reservoirs are provided in a channel substrate correspondingly to various colors of ink. Two or more dummy nozzles which are not used for performing printing/recording are provided between printing/recording nozzles for jetting ink of different colors. A space wide enough to disposed therein at least two nozzles is provided between the dummy nozzles. Consequently, adjacent and different-color ink is not mixed, and nozzles having unstable operation and disposed near the side walls of the ink reservoirs are not used for performing printing/recording, so that images of high quality can be obtained.