Sharp Kabushiki Kaisha Corporation

Junya Onishi

Kazuya Ishihara

Nobuyoshi Awaya

Yukio Tamai

Shinobu Yamazaki

Yoshihisa Adachi

Tetsuya Okumura

Mitsuru Nakura

Rieko Ogawa

Suguru Kawabata

Yushi Inoue

Takashi Nunokawa

Pulse waves of a living body are detected with high accuracy. A pulse wave detection device includes a camera configured to capture an image of the living body a plurality of times through a first green filter and an infrared light filter having light transmission characteristics in a near-infrared light wavelength range within a wavelength range where a light absorption coefficient of oxidized hemoglobin is greater than a light absorption coefficient of reduced hemoglobin, and an image analysis unit configured to analyze a plurality of images of the living body captured by the camera and to detect the pulse waves of the living body. The image analysis unit is configured to detect the pulse waves by detecting a change in intensity of light in the near-infrared light wavelength range indicated by the plurality of images.

Pulse wave detection device, image analysis device, and biometric information generation system

In a semiconductor memory device using a variable resistive element made of a metal oxide for storing information, a voltage amplitude of a writing voltage pulse for changing the variable resistive element to a high resistance state is set within a voltage range in which the resistance value of the high resistance state after the change increases with time. The voltage amplitude is set within the voltage range in which the resistance value of the high resistance state after the change increases toward a predetermined peak with increase in voltage amplitude. When a data error is detected by the ECC circuit, it is estimated that the data that should be in the low resistance state changes to the high resistance state, and the variable resistive elements of all memory cells from which the error is detected are written to the low resistance state to correct the error bit.

Semiconductor memory device

A variable resistance element that can stably perform a switching operation with a property variation being reduced by suppressing a sharp current that accompanies completion of forming process, and a non-volatile semiconductor memory device including the variable resistance element are realized. The non-volatile semiconductor memory device uses the variable resistance element for storing information in which a resistance changing layer is interposed between a first electrode and a second electrode, and a buffer layer is inserted between the first electrode and the resistance changing layer where a switching interface is formed. The buffer layer and the resistance changing layer include n-type metal oxides, and materials of the buffer layer and the resistance changing layer are selected such that energy at a bottom of a conduction band of the n-type metal oxide configuring the buffer layer is lower than that of the n-type metal oxide configuring the resistance changing layer.

Non-volatile semiconductor device

A nonvolatile semiconductor memory device includes a memory cell array for storing user data provided by arranging memory cells each having a variable resistive element having a first electrode, a second electrode, and a variable resistor made of a metal oxide sandwiched between the first and second electrodes. The first and second electrodes are formed of a conductive material forming ohmic junction with the variable resistor and a conductive material forming non-ohmic junction with the variable resistor, respectively. The variable resistor changes between two or more different resistance states by applying a voltage between the electrodes. The resistance state after being changed is maintained in a nonvolatile manner. The variable resistive elements of all memory cells in the memory cell array are set to the highest of the two or more different resistance states in an unused state before the memory cell array is used to store the user data.

Nonvolatile semiconductor memory device

Growing community of inventors

Osaka, Japan

Junya Onishi