Hitachi, Ltd.

Katsuyuki Tanaka

Yoshinori Takeuchi

Fumitaka Muranushi

Yuzo Yamaguchi

Hiroshi Daito

Kanji Kawakami

Tetsuo Masukawa

Katsuhiko Kimura

Nobuhiro Tokushuku

Hidehiko Kando

Shozo Saegusa

Tomomi Okamoto

Takashi Takeuchi

Masaki Ohura

Ikuo Nishida

Masaaki Kurebayashi

Hideaki Amano

Kyuichiro Nagai

Hiroshi Tani

Masaru Muranishi

Yokuo Saitoh

Tohru Sampei

Katsuo Abe

Yoshie Kodera

Muneo Mizumoto

Tatsumi Nishijima

Katsuo Konishi

Yoshihiko Noro

Kouhei Takita

Hitoshi Yanagihara

Shin-ichi Ohashi

Shinichi Hirose

Masakatsu Saito

Mamoru Kainuma

Youichi Inoue

Yoshihiro Sato

Katsuhiko Izumi

Yoichi Inoue

Toshiyasu Sawano

Kouichi Moritani

Seiichiroo Terashima

Toshiko Odaka

Yokuo Saito

Yuzoo Yamaguchi

Yohichi Inoue

Yoshinori Takeuchui

Isao Koromegawa

The speed of a disc handling operation by a disc apparatus having disc changer capability is significantly increased and, at the same time, the disc handling operation is performed with stability. In the disc apparatus according to this invention, a plurality of reproducing units loaded with discs are moved independently and disc reproduction is started by returning the reproducing units to their dedicated positions. Simultaneous returning of the plurality of reproducing units is prevented and each reproducing unit moves for refuge while reproducing the disc. This novel setup significantly shortens the time for moving the reproducing units for disc reproduction. When continuously reproducing a plurality of discs accommodated in proximity, the plurality of reproducing units are moved in a stacked state rather than independently. This also contributes to a significant reduction of the time in the disc handling operation. Further, when raising the lower reproducing unit in the stack, it is moved together with the upper reproducing unit; when raising the upper reproducing unit, it is separated from the lower reproducing unit for independent movement. This prevents the reproducing units from colliding against each other. The novel constitution significantly enhances ease of use of the disc apparatus.

Disc auto changer for recording or reproducing information on a desired

A video optical disk system which can record/reproduce information in the same recording format as that of a read only type optical disk such as an LD, and is therefore compatible with both the read only type optical disk and a writable optical disk. A writable optical disk exhibiting a C/N ratio of at least 60 [dB] is employed, and has information recorded thereon with the same address signals as those of the LD and in the NTSC direct FM recording format. An optical head and an image processing circuit which are included in a player unit are made common to the recorded disk and the LD, and characteristics of a focusing/tracking control circuit, an RF signal preamplifier circuit and a tilt control circuit which are included in the player unit are changed over on the basis of reflectances of both types of optical disks, thereby enabling both the recorded disk and the LD to be reproduced. The users of the optical disk system can produce original video software by themselves, and can effectively utilize a software stock of read only type optical disks.

Video optical disk system compatible with both read only and writable

In an optical scanning type tunneling microscope, reference light is prepared in addition to light used to be projected to a sample, and this reference light and also light picked up from an optical probe are caused to interfere with each other. As a result, phase information of light about a region having a very smaller dimension than a wavelength of the light irradiated from alight source can be acquired.

Interferometer, optical scanning type tunneling microscope and optical

The present invention provides a magnetic recording medium wherein the surface layer of the protective film of the medium is irradiated by ions to give a protective film having high reliability in resistance to sliding with the magnetic head, a process for producing the medium, an apparatus for producing the medium, and a magnetic recording apparatus having the medium mounted therein. The essentials of the present invention lie in introducing a minute surface roughness of atomic order in the surface of the protective film 5 constituting the outermost layer of a magnetic recording medium by irradiating atoms accelerated by high voltage (that is, by implanting ions) to the surface.

Magnetic recording medium, process for producing magnetic recording

A flying head slider has a slider body in which gas bearing rails are formed on a surface thereof disposed in opposed relation to a recording medium. A bleed portion is also provided at the surface of the slider body between a pair of gas bearing rails. The bleed portion is composed of at least a rectangular-shaped deep bleed portion in which the pair of longer sides thereof are directioned in parallel to the longitudinal axis direction of the gas bearing rails.

Flying head slider and method of producing the same

An apparatus for measuring the clearance between a recording transducer and a recording medium, which includes at least a conductive layer or conductive section, comprises a field electron emission electrode section disposed on the recording transducer, a voltage source for applying a voltage, which is greater at least in its peak value than the work functions of the electrode section and the conductive layer or conductive section of the recording medium, between the electrode section and the conductive layer or conductive section of the recording medium, a current measuring device for measuring the current flowing from the voltage source to the electrode section and the conductive layer or conductive section of the recording medium, and a computation processor for calculating the distance between the electrode section and the recording medium from the value of current measured by the current measuring device. A recording apparatus having the recording transducer clearance measuring apparatus is designed to support the recording transducer, which records and reproduces data on the recording medium, with a recording transducer supporting device through an advance/retract mechanism and to drive the mechanism in accordance with the distance calculated by the computation processor so as to adjust appropriately the clearance between the recording transducer and recording medium. A control method for the recording apparatus alters the operational condition of the recording apparatus if the clearance has exceeded a certain preset value.

Apparatus for measuring the clearance of recording transducer, and a

A flying head slider has gas bearing rails formed on a surface thereof disposed in opposed relation to a recording medium. The flying head slider flies at a microscopic distance above the recording medium by a pressure produced by a stream of gas resulted from the rotation of the recording medium. Each of the gas bearing rails comprises an inflow portion disposed at an inflow side of the gas stream so as to produce a pressure, an outflow portion disposed at an outflow side of the gas stream so as to produce a pressure, and a connective portion interconnecting the inflow portion and the outflow portion in a common plane. The connective portion serves to suppress an excessive compression of the gas, and achieves good damping characteristics.

Flying head slider and magnetic disk unit employing same

There is provided a magnetic recording device including recording mediums and an airtight enclosure containing the recording mediums therein and having a fine breathing hole created therethrough communicating with the outside thereof, wherein at least two types of moisture adsorbents composed of a one way type moisture adsorbent which adsorbs moisture and a reversible type moisture adsorbent which adsorbs moisture in high humidity and conversely discharges the same in low humidity are disposed in the cabinet and used in combination. There is also provided the same device except wherein gas adsorbents and moisture adsorbents are used in combination.

Magnetic disk device including humidity controller in disk enclosure

A flying head slider for supporting a magnetic head operative to transmit information into and out of a recording medium has a slider body having a surface to be disposed in faced relationship to the recording medium. Positive pressure generating portions are formed on the surface of the slider body to generate a positive pressure during rotation of the recording medium relative to the slider body. A bearing is formed in the fluid-inlet end of each positive pressure generating section to enhance a bearing action due to abrupt compression of fluid. A bleed slot is defined between the positive pressure generating sections and has a fluid-inlet end provided with a negative pressure generating means, whereby the slider stably floats a predetermined distance away from the recording medium during rotation thereof to enable the magnetic head to transmit information.

Flying head slider

One of two articles arranged to form a fine clearance therebetween is made of a transparent material through which a light flux is impinged to the other article to form a reflection light which includes an interference fringe pattern information representing the fine clearance between the two articles. The reflection light is focused on a photo-electric conversion plane and converted to an electrical signal. The photo-electrically converted interference fringe pattern information is then converted to digital information, which is stored in a frame memory. A computer reads out the digital information from the frame memory and determines peak positions of light and/or dark areas of the interference fringe to measure the fine clearance between the two articles.

Fine clearance measuring apparatus

A slider equipped with a magnetic head is pressed on a magnetic disk surface under a constant pressure by a pressing member. The slider is loaded and unloaded by a loading/unloading mechanism. A driving unit of the loading/unloading mechanism has a shape memory alloy member which offers a shape memory effect based on the thermoelastic martensitic transformation, and a resilient member having a resilient force against the driving force of the shape memory alloy member. Moreover, the loading/unloading mechanism is arranged such that when the slide is loaded, the driving force of the loading/unloading mechanism is not applied to the pressing member supporting the slider.

Load/unload suspension device for a magnetic disc apparatus

A drive circuit for an electroluminescent (EL) element whose brightness can be changed by changing a voltage or the frequency of the voltage applied to the EL element and can be kept constant by keeping the current flowing through the EL element constant is disclosed. The drive circuit is provided with a drive power source whose output voltage or output voltage frequency is variable by a control signal. The output of the drive power source is supplied to the EL element. The current flowing through the EL element is detected by a current detecting element and a signal related to the detected current is applied as the control signal to the drive power source to subject the EL element to a constant-current drive.

Drive circuit for electroluminescent element

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Ibaraki, Japan

Katsuyuki Tanaka