Hitachi, Ltd.

Masakatsu Saito

Masamichi Yamada

Toshio Tsuchiya

Katsuo Konishi

Masaaki Kurebayashi

Tohru Sampei

Katsuyuki Tanaka

Hitoshi Yanagihara

Mitsuo Abe

Shin-ichi Ohashi

Yukiko Ogura

Takumi Sasaki

Disclosed herein is a magnetic head in which the sliding surface is constructed of a transducing gap, a pair of soft magnetic metal films opposite to each other through the transducing gap, and a substrate holding the soft magnetic metal film. The substrate is 20-200 times as wear-resistant as the soft magnetic metal film. The magnetic head has a gap depth of 1-5 .mu.m and produces an overall high head output.

Magnetic head

In a thin film magnetic head consisting of a non-magnetic substrate, and a multilayer structure superposed thereon and including a lower core, a gap material layer, a thin film coil and an upper core, etc., the head sliding surface of the lower core and that of the upper core are so formed that they become wider with increasing distance from the surface of the gap material layer.

Thin film magnetic head

Multi-track magnetic thin film heads for recording and reproducing an analog signal of an electronic still camera. The heads are constructed on a single non-magnetic substrate. Each of lower magnetic cores for the heads is separately formed in the surface of the non-magnetic substrate, in order to reduce cross talk from adjacent tracks. Further, in order to decrease a resistance of a coil thereof, a distance of back head gap parts of adjacent heads is formed larger than a distance of front head gap parts of the adjacent heads. As the non-magnetic substrate, a ceramic material comprising at least MnO and NiO are used, as a magnetic core material, an amorphous material including Co, Nb and Zr is used, and as a magnetic gap material, Cr or Zr is used.

Multi-track magnetic thin film heads

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

Growing community of inventors

Yokohama, Japan

Masakatsu Saito