Semiconductor Energy Laboratory Co., Ltd.

Yu Yamazaki

Mitsuaki Osame

Aya Anzai

Shunpei Yamazaki

Jun Koyama

Hajime Kimura

Ryota Fukumoto

Tomoyuki Iwabuchi

Masato Yonezawa

Yoshifumi Tanada

Keisuke Miyagawa

Satoshi Seo

Masayuki Sakakura

Masahiko Hayakawa

Mai Akiba

Yukari Ando

Tamae Takano

Takashi Hamada

Ritsuko Nagao

Aya Anazai

Yoshiharu Hirakata

Takayuki Ikeda

Takeshi Fukunaga

Satoshi Murakami

Hiroshi Shibata

Hidehito Kitakado

Hiroko Abe

Yasuko Watanabe

Etsuko Fujimoto

Takeshi Nishi

Yasuo Nakamura

Kazuo Nishi

Keisuke Hayashi

Shou Nagao

A potential of a gate of a driving transistor is fixed, and the driving transistor is operated in a saturation region, so that a current is supplied thereto anytime. A current control transistor operating in a linear region is disposed serially with the driving transistor, and a video signal for transmitting a signal of emission or non-emission of the pixel is input to a gate of the current control transistor via a switching transistor.

Element substrate and light-emitting device

A light emitting device and an element substrate which are capable of suppressing variations in luminance intensity of a light emitting element among pixels due to characteristic variations of a driving transistor without suppressing off-current of a switching transistor low and increasing storage capacity of a capacitor. A gate potential of a driving transistor is connected to a first scan line or a second scan line, and the driving transistor operates in a saturation region. A current controlling transistor which operates in a linear region is connected in series to the driving transistor. A video signal which transmits a light emission or non-emission of a pixel is input to the gate of the current controlling transistor through a switching transistor.

Element substrate and light emitting device

When writing a signal current from a current source to a current source circuit, noise occurs in some cases in a wiring through which a current flows, which may cause a potential of the wiring to be outside the normal range. As the potential does not turn back within the normal range easily at this time, writing to the current source circuit is delayed. According to the invention, when the potential becomes outside the normal range due to noise occurring in a wiring through which a current flows when writing a signal current from a current source to a current source circuit, a current is supplied from other than the current source, thereby the potential of the wiring can turn back within the normal range rapidly.

Semiconductor device having rectifying elements connected to a pixel of a display device

An area sensor of the present invention has a function of displaying an image in a sensor portion by using light-emitting elements and a reading function using photoelectric conversion devices. Therefore, an image read in the sensor portion can be displayed thereon without separately providing an electronic display on the area sensor. Furthermore, a photoelectric conversion layer of a photodiode according to the present invention is made of an amorphous silicon film and an N-type semiconductor layer and a P-type semiconductor layer are made of a polycrystalline silicon film. The amorphous silicon film is formed to be thicker than the polycrystalline silicon film. As a result, the photodiode according to the present invention can receive more light.

Area sensor and display apparatus provided with an area sensor

A photodetector of the invention is characterized by having a plurality of detector elements that are arranged over a light-transparent substrate and are connected in parallel. A foldable portable communication tool having two display portions of the invention is characterized by including one photodetector which includes a plurality of detector elements connected in parallel.

Multidirectional photodetector, a portable communication tool having thereof and a method of displaying

Semiconductor device having a rectifying element connected to a pixel of a display device

There is provided a method for deciding a duty factor in driving a light-emitting device and a driving method using the duty factor that enable restraint of deterioration of light-emitting elements and improvement in reliability. In a method for deciding a duty factor of a light-emitting device that performs display based on an analog video signal, with respect to a characteristic obtained by multiplying the characteristic of luminance after X hours in relation to the current density and the characteristic of luminance after X hours in relation to the duty factor when the total quantity of electricity flowing through light-emitting elements in one frame period is defined at a specific value, a range of duty factor that enables realization of luminance approximately exceeding a value that is 0.8 times a maximum value is regarded as an optimum range of duty factor.

Method for deciding duty factor in driving light-emitting device and driving method using the duty factor

A light emitting device and an element substrate which are capable of suppressing variations in the luminance intensity of a light emitting element among pixels due to characteristic variations of a driving transistor without suppressing off-current of a switching transistor low and increasing storage capacity of a capacitor. According to the invention, a depletion mode transistor is used as a driving transistor. The gate of the driving transistor is fixed in its potential or connected to the source or drain thereof to operate in a saturation region with a constant current flow. A current controlling transistor which operates in a linear region is connected in series to the driving transistor, and a video signal for transmitting a light emission or non-emission of a pixel is inputted to the gate of the current controlling transistor through a switching transistor.

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Tokyo, Japan

Yu Yamazaki