Sharp Kabushiki Kaisha Corporation

Sekisui Chemical Co., Ltd.

Yasuyuki Shirasaka

Nobuto Kamiya

Tetsuhiro Kato

Yuuta Katsurayama

Masahiro Tsuchiya

Norikazu Okada

Takayuki Shimizu

Takuma Hiramatsu

Ryousuke Takahashi

Kohei Yasukawa

Katsuyuki Kawamura

The present invention provides an electret sheet that has excellent durability against a pressing force that is repetitively applied, that is, excellent compression recovery properties, and can suppress stuffiness even when used by attaching it to the skin of a human body. The electret sheet of the present invention has an air permeability of 10 to 1,000 sec/100 mL. Thus, the electret sheet has excellent durability against a pressing force that is repetitively applied, that is, excellent compression recovery properties, and can suppress stuffiness even when used by attaching it to the skin of a human body.

Electret sheet and piezoelectric sensor

The present invention provides an electret sheet that exhibits excellent piezoelectricity even by light stress. The electret sheet of the invention is characterized by including a charged porous sheet, in which the electret sheet has a compressive elastic modulus of 80 to 300 MPa when compressively deformed at 25&#xb0; C. and a 50% compression stress of 120 to 300 kPa at 25&#xb0; C., and thus has the excellent piezoelectricity for light stress and exhibits the excellent piezoelectricity even by light stress (0.5N or less) caused by a pulse wave or a breathing.

Electret sheet

The present invention provides an electret sheet that exhibits excellent piezoelectricity even by light stress. The electret sheet of the invention is characterized by including a charged porous sheet, in which the electret sheet has a compressive elastic modulus of 80 to 300 MPa when compressively deformed at 25&#xb0; C. and a 50% compression stress of 120 to 300 kPa at 25&#xb0; C., and thus has the excellent piezoelectricity for light stress and exhibits the excellent piezoelectricity even by light stress (0.5 N or less) caused by a pulse wave or a breathing.

The present invention provides an electret sheet that retains high piezoelectricity under high-temperature condition. The electret sheet of the invention is characterized by including a charged porous sheet, in which the electret sheet has a volume resistivity of 1.0&#xd7;10&#x3a9;&#xb7;cm or more at 25&#xb0; C. and a dielectric breakdown voltage of 7 kV or more at 25&#xb0; C. The electret sheet preferably having a volume resistivity of 1.0&#xd7;10&#x3a9;&#xb7;cm or more at 37&#xb0; C. and a dielectric breakdown voltage of 7 kV or more at 37&#xb0; C. retains excellent piezoelectricity even after being left under a high-temperature atmosphere over a long period.

Disturbance noise is distinguished and an appropriate detection result is output in accordance with a state of each disturbance noise. A signal processing circuit () of a photodetection device () includes non-synchronous detection units () that detect existence of a light reception signal which is not synchronous with a light emitting drive timing in at least one of a case where it is determined that a value of the light reception signal exceeds a predetermined first threshold and a case where the value of the light reception signal becomes less than a predetermined second threshold in a non-synchronous detection period except a synchronous detection period in a detection period in the signal processing circuit (). In addition, is a case where existence of the light reception signal which is not synchronous with the light emitting drive timing is detected by the non-synchronous detection units (), the signal processing circuit () maintains a result of the detection of the existence/non-existence of the light reception signal acquired by the synchronous detection unit in a subsequent detection period.

Photodetection device with synchronous and non-synchronous light detection for reducing noise and electronic apparatus

In order to provide an optical sensor that can accurately sense a direction of movement of an object to be sensed even in a case where disturbance light is present, an optical sensor of the present invention includes: a light-emitting element; a circularly-segmented light-receiving element group (RDPD), including light-receiving elements circularly provided at edges of a region on which reflected light from an object to be sensed reflecting light emitted by the light-emitting element is incident, for generating respective photocurrents upon receiving the reflected light; and a gesture circuit section for sensing a direction of movement of the object to be sensed upon receiving the photocurrents generated by the light-receiving elements included in the circularly-segmented light-receiving element group (RDPD).

Optical sensor and electronic device

An object is sensed without a malfunction due to disturbance light. An optical sensor () of an aspect of the invention includes: a light-emitting element (LED) which turns off and turns on alternately for each one period; a light-receiving element (PD) which receives reflection light and generates a photocurrent; and an integrating circuit () which integrates the photocurrent in a positive direction in a period during which the light-emitting element turns on and integrates the photocurrent in a negative direction in a period during which the light-emitting element turns off. A sum of lengths of integration periods in a first period and a last period is same as a length of another integration period.

The optical sensor includes a photodiode PDwith its anode grounded, a diode group DGhaving one end connected to a cathode of the photodiode PD, a current source Ihaving one end connected to the other end of the diode group DG, a power supply section for applying a constant voltage to the other end of the current source I, and a grounded-emitter NPN transistor Qhaving a base connected to the cathode of the photodiode PDand a collector connected to one end of the current source I. The diode group DGis provided by n diodes D, D, . . . , Dconnected in series so that their forward directions are directed toward the photodiode PDside, and a photocurrent which flows from a connecting point between the diode group and the current source to the photodiode is converted into a voltage and outputted as a photoelectric conversion signal.

Optical sensor and electronic equipment

A decoder device has a reference voltage generating section for outputting first and second threshold level signals, a first comparator for comparing a stair-stepped waveform input signal and the first threshold level signal to output a comparison result, a second comparator for comparing the input signal and the second threshold level signal to output a comparison result, and a logical operation section for performing a logical operation between output signals of the first and second comparators to output a signal decoded from the input signal. A threshold level represented by the first threshold level signal intersects a riser section of one stepped waveform out of two adjacent stepped waveforms in the input signal, and a threshold level represented by the second threshold level signal intersects a riser section of the other stepped waveform out of the two adjacent stepped waveforms of the stair-stepped waveform input signal.

Decoder device and movement controller

A decoder circuit of the present invention, mounted on an integrated circuit, decodes input voltage Vin supplied to a single external input terminal into three or more control outputs, and an object of the present invention is to reduce the size of a chip. The foregoing decoder circuit includes: a P-type transistor in which an emitter is connected to a power source line of high level, a base is connected to the external input terminal, and a collector is an output terminal of a first control output; and an N-type transistor in which an emitter is connected to a power source line of low level, a base is connected to the external input terminal, and a collector is an output terminal of a second control output, and decodes the control outputs to three or more sets of data by carrying out logic operations. Therefore, as compared to the case of using a comparator requiring many transistors, a constant current source, and other elements, one each transistor is required for each of the two control outputs to be generated. This facilitates size reduction of a chip.

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Osaka, Japan

Yasuyuki Shirasaka