Abstract: Members such as a laser diode (10) that is a light source, a diffraction grating (11), a polarizing beam splitter (12) and a collimator lens are arranged in a casing (20). An optical head device having such a casing (20) is improved, so that a film wavelength plate (14) is directly attached to the casing (20) in a form free from a support substrate. The film wavelength plate (14) consists of only one film and has a thickness of 0.2 to 1.0 mm. Particularly, the film wavelength plate is preferably constituted by fusing polycarbonate films in a three-layer structure.

Abstract: A storage control apparatus concatenates a plurality of logical units to construct a large capacity logical unit, wherein logical units extending over a plurality of controllers can be concatenated. The channel adapter sends an I/O request to one controller which charges one logical unit constituting the concatenation logical unit, out of a plurality of controllers when an I/O request is sent from a host to the concatenation logical unit LU linking a plurality of logical units, executes I/O processing in the one controller, then sends the I/O request to another controller which charges another logical unit constituting the concatenation logical unit, and continues I/O processing in the another controller.

Abstract: A phase difference plate is formed by bonding a fixed substrate which has a transmission function or a reflection function to at least one of surfaces of an organic thin film through an adhesive. The phase difference plate has a relation of E1?E2>E3 wherein E1 is a linear expansion coefficient of the organic thin film, E2 is a linear expansion coefficient of the adhesive, and a linear expansion coefficient E3 of the fixed substrate. When the laser wavelength is fluctuated by temperature change, phase difference is changed so as to match to the fluctuation of wavelength. An optical head device has the phase difference plate in such a way that an arrangement position of the phase difference plate is changeable.

Abstract: An I/O control device that transfers data according to transfer control information, comprising a transfer control information memory means that stores transfer control information, a state detecting means that detects the processed state of the transfer control information stored in the transfer control information memory means, and a transfer control information memory control means by which new transfer control information is stored in the transfer control information memory means in place of the transfer control information upon completion of transfer control information-dependent transfer processing as a result of the detection by the state detecting means.

Abstract: A storage control apparatus concatenates a plurality of logical units to construct a large capacity logical unit, wherein logical units extending over a plurality of controllers can be concatenated. The channel adapter sends an I/O request to one controller which charges one logical unit constituting the concatenation logical unit, out of a plurality of controllers when an I/O request is sent from a host to the concatenation logical unit LU linking a plurality of logical units, executes I/O processing in the one controller, then sends the I/O request to another controller which charges another logical unit constituting the concatenation logical unit, and continues I/O processing in the another controller.

Abstract: An I/O control device that transfers data according to transfer control information, comprising a transfer control information memory means that stores transfer control information, a state detecting means that detects the processed state of the transfer control information stored in the transfer control information memory means, and a transfer control information memory control means by which new transfer control information is stored in the transfer control information memory means in place of the transfer control information upon completion of transfer control information-dependent transfer processing as a result of the detection by the state detecting means.

Abstract: In a drive circuit of a half-bridge inverter circuit, a stable operation cannot be performed at a start-up time and a problem exists such that if a high side output signal is first outputted, main switching elements and are simultaneously turned on. In the present invention, a start-up circuit comprising a latch circuit and a gate circuit are provided, the latch circuit is set while prioritizing a low-side signal, and a low-side output signal is always first made high level, thereby realizing a half-bridge inverter circuit which can start up wit a stability.

Abstract: In a drive circuit of a half-bridge inverter circuit, a stable operation cannot be performed at a start-up time and a problem exists such that if a high side output signal is first outputted, main switching elements and are simultaneously turned on. In the present invention, a start-up circuit comprising a latch circuit and a gate circuit are provided, the latch circuit is set while prioritizing a low-side signal, and a low-side output signal is always first made high level, thereby realizing a half-bridge inverter circuit which can start up wit a stability.

Abstract: In the present invention, a vertical type MOSFET and a Schottky barrier diode which are used as a switching device of a DC--DC converter are formed on the same semiconductor substrate. Further, a barrier metal which is required for the Schottky barrier diode is also formed on an electrode portion of the vertical type MOSFET. In addition, a Schottky barrier diode forming region is formed to have low impurity concentration than a vertical type MOSFET forming region.