Abstract: To provide a small-sized and reliable optical module in which a light emitting element and an optical function element respectively remarkably different in a coefficient of thermal expansion are mounted in the same casing, in the invention, the optical function element is mounted on the casing made of first material substantially equal in a coefficient of thermal expansion to the optical function element, a light emitting element unit including the light emitting element (for example, a thermoelectric module over which the light emitting element is mounted) is mounted on a member (base material) made of second material different from the first material and matched with the light emitting element unit in a coefficient of thermal expansion, and the member is, for example, embedded in the bottom of the casing.

Abstract: Included are: a gain chip having a gain unit and a phase control region; a current supply for causing a positive current to flow to the phase control region; a voltage supply for applying a bias voltage to the phase control region; and a control unit for selectively driving the current supply or the voltage supply depending on a direction of the wavelength shift. The control unit drives the current supply when a laser wavelength is to be shifted to a shorter wavelength side from a wavelength with the current supply and the voltage supply being turned off, and drives the voltage supply when the laser wavelength is to be shifted to a longer wavelength side from a wavelength with the current supply and the voltage supply being turned off.

Abstract: The present invention provides a compact, highly reliable optical module in which a light-emitting element and optical modulator element that differ from each other in thermal expansion coefficient are mounted in one casing. In the optical module having a differential thermal expansion coefficient less than 5×10?6 [1/K] between the light-emitting element and the casing, and a differential thermal expansion coefficient of at least 5×10?6 [1/K] between the optical modulator element and the casing, a section at which the optical modulator element and the casing are fixed is equal to or less than 10 mm wide in the direction of an optical axis.

Abstract: The present invention provides an optical transmission module comprising: a laser diode; a lens for condensing a laser beam from the laser diode; a fiber ferrule which is placed so that the laser beam condensed by the lens can enter a fiber core; and a lens aperture or a lens aperture portion which is provided at one of the lens itself, a position before the lens and a position after the lens. In addition, the present invention provides an optical transmission module in which instead of the lens aperture, an effective diameter of the lens on the fiber ferrule side is set at a value ranging from 0.1 times to less than 0.2 times of a distance between an emittance plane of the lens and an incidence plane of the fiber ferrule.

Abstract: To provide a small-sized and reliable optical module in which a light emitting element and an optical function element respectively remarkably different in a coefficient of thermal expansion are mounted in the same casing, in the invention, the optical function element is mounted on the casing made of first material substantially equal in a coefficient of thermal expansion to the optical function element, a light emitting element unit including the light emitting element (for example, a thermoelectric module over which the light emitting element is mounted) is mounted on a member (base material) made of second material different from the first material and matched with the light emitting element unit in a coefficient of thermal expansion, and the member is, for example, embedded in the bottom of the casing.

Abstract: There is provided an optical module in which electrical wirings in a module package are simplified without increasing a manufacturing cost. A light emitting element is mounted on a substrate having electrical wirings therein. In the substrate, electrodes connected to the electrical wirings are formed at a side where the light emitting element is mounted. The light emitting element and the electrodes of one ends of the wirings are wire-bonded to each other and one ends of leads and the electrodes the other ends of the wirings are wire-bonded to each other.

Abstract: The present invention relates to an optical transmission module comprising two substrates, each of which has an electronic part mounted on the substrate and a terminal area for inputting/outputting an electric signal into/from the electronic part, wherein an electrical connection is made between the terminal areas of said two substrates by use of a flexible substrate having a structure constituted of at least three layers, and thereby a high frequency signal is transmitted between the electronic part mounted on one substrate and the electronic part mounted on the other substrate through the flexible substrate while confining an electromagnetic field. In addition, the present invention provides an optical transmission module characterized in that a slit formed in a ground plane on a connection section of a three-layer flexible substrate reduces a disturbance in electromagnetic field, making it possible to improve the transmission characteristic of a high frequency signal.

Abstract: The present invention provides a compact, highly reliable optical module in which a light-emitting element and optical modulator element that differ from each other in thermal expansion coefficient are mounted in one casing. In the optical module having a differential thermal expansion coefficient less than 5×10?6 [1/K] between the light-emitting element and the casing, and a differential thermal expansion coefficient of at least 5×10?6 [1/K] between the optical modulator element and the casing, a section at which the optical modulator element and the casing are fixed is equal to or less than 10 mm wide in the direction of an optical axis.

Abstract: The object of the present invention is to provide a device with a simple structure which can uniformly mix bulk materials. A device comprises a rotary shaft 6 to be rotated by a driving means 3, a container outer shell 7 fixed to the rotary shaft 6 to tilt relative to the rotary shaft 6, and an inner shell 9 fixed inside the container outer shell 7. Bulk materials are put into a receiving space 13 formed between the container outer shell and the inner shell and are then agitated and mixed.

Abstract: A high-frequency signal from a tape-shaped line section having a surface layer signal lead and surface layer GND lead disposed on both sides thereof is directly inputted to a semiconductor chip via a signal surface layer wiring of a package substrate and through solder bump electrodes. Alternatively, a high-frequency signal from the semiconductor chip is outputted to the outside via the tape-shaped line section in reverse. Owing to the transmission of the high-frequency signal by only a microstrip line at the whole surface layer of the package substrate, the high-frequency signal can be transmitted by only the microstrip line at the surface layer without through vias or the like. Accordingly, the high-frequency signal can be transmitted without a loss in frequency characteristic, and a high-quality high-frequency signal can be transmitted with a reduction in loss at high-frequency transmission.

Abstract: A high-frequency signal from a tape-shaped line section having a surface layer signal lead and surface layer GND lead disposed on both sides thereof is directly inputted to a semiconductor chip via a signal surface layer wiring of a package substrate and through solder bump electrodes. Alternatively, a high-frequency signal from the semiconductor chip is outputted to the outside via the tape-shaped line section in reverse. Owing to the transmission of the high-frequency signal by only a microstrip line at the whole surface layer of the package substrate, the high-frequency signal can be transmitted by only the microstrip line at the surface layer without through vias or the like. Accordingly, the high-frequency signal can be transmitted without a loss in frequency characteristic, and a high-quality high-frequency signal can be transmitted with a reduction in loss at high-frequency transmission.

Abstract: The present invention relates to an optical transmission module comprising two substrates, each of which has an electronic part mounted on the substrate and a terminal area for inputting/outputting an electric signal into/from the electronic part, wherein an electrical connection is made between the terminal areas of said two substrates by use of a flexible substrate having a structure constituted of at least three layers, and thereby a high frequency signal is transmitted between the electronic part mounted on one substrate and the electronic part mounted on the other substrate through the flexible substrate while confining an electromagnetic field.

Abstract: Provided is a magnetic disc apparatus comprising a magnetic head for writing and reading data to and from a magnetic disc, a slider for floating up the magnetic head from the magnetic disc on rotation, a suspension having an IC chip mounting surface, for supporting the slider, a positioning mechanism for positioning a magnetic head at a predetermined position, and an IC chip mounted on the IC chip supporting surface of the suspension, wherein the rate of variation in temperature difference between opposite sides of the IC chip mounting position as a center on the IC chip mounting surface is set to be below about 3.5 K/sec. Thereby it is possible to restrain the averaged seek time for the magnetic disc from becoming longer.

Abstract: The present invention provides an optical transmission module comprising: a laser diode; a lens for condensing a laser beam from the laser diode; a fiber ferrule which is placed so that the laser beam condensed by the lens can enter a fiber core; and a lens aperture or a lens aperture portion which is provided at one of the lens itself, a position before the lens and a position after the lens.

Abstract: A high-frequency signal from a tape-shaped line section having a surface layer signal lead and surface layer GND lead disposed on both sides thereof is directly inputted to a semiconductor chip via a signal surface layer wiring of a package substrate and through solder bump electrodes. Alternatively, a high-frequency signal from the semiconductor chip is outputted to the outside via the tape-shaped line section in reverse. Owing to the transmission of the high-frequency signal by only a microstrip line at the whole surface layer of the package substrate, the high-frequency signal can be transmitted by only the microstrip line at the surface layer without through vias or the like. Accordingly, the high-frequency signal can be transmitted without a loss in frequency characteristic, and a high-quality high-frequency signal can be transmitted with a reduction in loss at high-frequency transmission.

Abstract: A high-frequency signal from a tape-shaped line section having a surface layer signal lead and surface layer GND lead disposed on both sides thereof is directly inputted to a semiconductor chip via a signal surface layer wiring of a package substrate and through solder bump electrodes. Alternatively, a high-frequency signal from the semiconductor chip is outputted to the outside via the tape-shaped line section in reverse. Owing to the transmission of the high-frequency signal by only a microstrip line at the whole surface layer of the package substrate, the high-frequency signal can be transmitted by only the microstrip line at the surface layer without through vias or the like. Accordingly, the high-frequency signal can be transmitted without a loss in frequency characteristic, and a high-quality high-frequency signal can be transmitted with a reduction in loss at high-frequency transmission.

Abstract: In an optical module including an optical element and a semiconductor IC for driving it in a case, a metal stem 35 on which an optical element 10 is mounted is provided with a wiring plate 11, a semiconductor IC 30 for electrically driving the optical element 10, and the wiring plate 11 are connected with each other by wires 16, and further the wiring plate 11 and the optical element 10 are connected with each other by the wires 16. The optical communication module having excellent high frequency characteristics is formed that shuts out influence of heat from the semiconductor IC upon the optical element and causes no interference between the semiconductor IC and optical connecting lenses.

Abstract: The object of the present invention is to provide a device with a simple structure which can uniformly mix bulk materials.