Abstract: An object is to provide a pulse signal output circuit capable of operating stably and a shift register including the pulse signal output circuit. A pulse signal output circuit according to one embodiment of the disclosed invention includes first to tenth transistors. The ratio W/L of the channel width W to the channel length L of the first transistor and W/L of the third transistor are each larger than W/L of the sixth transistor. W/L of the fifth transistor is larger than W/L of the sixth transistor. W/L of the fifth transistor is equal to W/L of the seventh transistor. W/L of the third transistor is larger than W/L of the fourth transistor. With such a structure, a pulse signal output circuit capable of operating stably and a shift register including the pulse signal output circuit can be provided.

Abstract: An object is to reduce leakage current and parasitic capacitance of a transistor used for an LSI, a CPU, or a memory. A semiconductor integrated circuit such as an LSI, a CPU, or a memory is manufactured using a thin film transistor in which a channel formation region is formed using an oxide semiconductor which becomes an intrinsic or substantially intrinsic semiconductor by removing impurities which serve as electron donors (donors) from the oxide semiconductor and has larger energy gap than that of a silicon semiconductor. With use of a thin film transistor using a highly purified oxide semiconductor layer with sufficiently reduced hydrogen concentration, a semiconductor device with low power consumption due to leakage current can be realized.

Abstract: An object is to reduce leakage current and parasitic capacitance of a transistor used for an LSI, a CPU, or a memory. A semiconductor integrated circuit included in an LSI, a CPU, or a memory is manufactured using the transistor which is formed using an oxide semiconductor which is an intrinsic or substantially intrinsic semiconductor obtained by removal of impurities which serve as electron donors (donors) from the oxide semiconductor and has larger energy gap than a silicon semiconductor, and is formed over a semiconductor substrate. With the transistor which is formed over the semiconductor substrate and includes the highly purified oxide semiconductor layer with sufficiently reduced hydrogen concentration, a semiconductor device whose power consumption due to leakage current is low can be realized.

Abstract: A semiconductor device including a first gate electrode and a second gate electrode formed apart from each other over an insulating surface, an oxide semiconductor film including a region overlapping with the first gate electrode with a gate insulating film interposed therebetween, a region overlapping with the second gate electrode with the gate insulating film interposed therebetween, and a region overlapping with neither the first gate electrode nor the second gate electrode, and an insulating film covering the gate insulating film, the first gate electrode, the second gate electrode, and the oxide semiconductor film, and being in direct contact with the oxide semiconductor film is provided.

Abstract: To provide a pulse signal output circuit capable of operating stably and a shift register including the pulse signal output circuit. A pulse signal output circuit includes a plurality of transistors each including an oxide semiconductor. In accordance with operations of the pulse signal output circuit, the threshold voltage of the transistor including an oxide semiconductor is changed. A shift register including the pulse signal output circuit is formed. A pulse signal output circuit capable of operating stably and a shift register including the pulse signal output circuit can be provided.

Abstract: A display device includes a display panel including a plurality of pixels, a shutter panel including a driver circuit, a liquid crystal, and light-transmitting electrodes provided in a striped manner, and a positional data detector configured to detect a positional data of a viewer. The shutter panel is provided over a display surface side of the display panel, a width of one of the light-transmitting electrodes in the shutter panel is smaller than that of one of the plurality of pixels, and the driver circuit in the shutter panel is configured to selectively output signals for forming a parallax barrier to the light-transmitting electrodes. The parallax barrier is capable of changing its shape in accordance with the detected positional data.

Abstract: An object is to suppress crosstalk. A display device includes a pixel portion which includes a first display region, a second display region, and a non-light-emitting region provided between the first display region and the second display region; and a parallax barrier which includes a first light control region, a second light control region, and a light-transmitting region provided between the first light control region and the second light control region. The first light control region overlaps with the first display region, the second light control region overlaps with the second display region, and the center of the width of the light-transmitting region overlaps with the non-light-emitting region.

Abstract: An object of the present invention is to provide a pulse signal output circuit capable of operating stably and a shift register including the pulse signal output circuit. In an embodiment of the pulse signal output circuit, a transistor has a source terminal or a drain terminal connected to a gate electrode of another transistor having a source terminal or a drain terminal forming an output terminal of the pulse signal output circuit, the channel length of the transistor being longer than the channel length of the other transistor. Thereby, the amount of a leakage current modifying the gate potential of the other transistor can be reduced, and a malfunction of the pulse signal output circuit can be prevented.

Abstract: A display device includes a plurality of pulse output circuits each of which outputs signals to one of the two kinds of scan lines and a plurality of inverted pulse output circuits each of which outputs, to the other of the two kinds of scan lines, inverted or substantially inverted signals of the signals output from the pulse output circuits. Each of the plurality of inverted pulse output circuits operates with at least two kinds of signals used for the operation of the plurality of pulse output circuits. Thus, through current generated in the inverted pulse output circuits can be reduced.

Abstract: A semiconductor circuit which can have stable input output characteristics is provided. Specifically, a semiconductor circuit in which problems caused by the leakage current of a switching element are suppressed is provided. A field-effect transistor in which a wide band gap semiconductor, such as an oxide semiconductor, is used in a semiconductor layer where a channel is formed is used for a switching element included in a switched capacitor circuit. Such a transistor has a small leakage current in an off state. When the transistor is used as a switching element, a semiconductor circuit which has stable input output characteristics and in which problems caused by the leakage current are suppressed can be fabricated.

Abstract: Provided are a liquid crystal display device with horizontal electric field mode, in which a decrease in driving speed can be suppressed by reducing the resistance of a wiring even when the number of pixels is increased, and a manufacturing method thereof. One of a scan wiring and a signal wiring is divided in an intersection portion where the scan wiring and the signal wiring intersect with each other, and the separated wirings are connected with a connection electrode positioned over a thick insulating film. Accordingly, parasitic capacitance at the intersection portion can be reduced, preventing the decrease in the driving speed. The connection electrode is formed at the same time as formation of a pixel electrode and a common electrode using a low-resistance metal, which contributes to the reduction in manufacturing process of the liquid crystal display device.

Abstract: Input of image signals to part of a plurality of pixels included in a particular region of a pixel portion and supply of light to part of another plurality of pixels which is different from the part are performed concurrently. Therefore, it is not necessary to provide a period in which light is supplied to all of the plurality of pixels included in the region after the image signals are input thereto. In other words, it is possible to start input of the next image signals to all of the plurality of pixels included in the region just after the image signals are input thereto. Accordingly, it is possible to increase the input frequency of the image signals. As a result, it is possible to suppress deteriorations of display caused in the field-sequential liquid crystal display device.

Abstract: To reduce crosstalk in sequential frame periods. An image signal is written to a pixel in a first sub-frame period. Then, just before a second sub-frame period, the light source is lit in accordance with the image signal written in the first sub-frame period and sequentially, the image signal is written in the second sub-frame period of the right eye frame period. Then, just before the next first sub-frame period, the light source is lit in accordance with the image signal in the third sub-frame period and sequentially, writing of the image signal is performed in the third sub-frame period of the right eye frame period.

Abstract: The novel structure of a backlight unit using color-scan backlight drive which structure can relieve the color mixture problem is provided. A backlight unit including: a light guide plate including (j+1) (j is a natural number) reflective walls that are columns having height in a direction perpendicular to a bottom face and being extended in one direction parallel to the bottom face and that are provided in parallel; an r-th columnar transparent layer provided in a region sandwiched between an r-th (r is a natural number, 1?r?j) reflective wall and an (r+1)-th reflective wall of the (j+1) reflective walls; and an r-th light source provided on a side surface of the light guide plate to let light into the r-th transparent layer.

Abstract: A semiconductor device including a first gate electrode and a second gate electrode formed apart from each other over an insulating surface, an oxide semiconductor film including a region overlapping with the first gate electrode with a gate insulating film interposed therebetween, a region overlapping with the second gate electrode with the gate insulating film interposed therebetween, and a region overlapping with neither the first gate electrode nor the second gate electrode, and an insulating film covering the gate insulating film, the first gate electrode, the second gate electrode, and the oxide semiconductor film, and being in direct contact with the oxide semiconductor film is provided.

Abstract: A reflective region where display is performed with reflection of incident light through a liquid crystal layer and a transmissive region where display is performed by transmission of light from a backlight are provided, and the reflective mode and the transmissive mode are switched. In the case of displaying a full-color image, a pixel portion includes at least a first region and a second region, a plurality of lights of different hues are sequentially supplied to the first region according to a first order, and a plurality of lights of different hues are also sequentially supplied to the second region according to a second order which is different from the first order. In the transmissive mode, the reflective region is made to display black, so that decrease in contrast due to reflection of external light at the reflective region is prevented.

Abstract: Provided is a liquid crystal display device having a pixel including a transistor and a liquid crystal element and a protection circuit electrically connected to one of a source and a drain of the transistor through a data line. The protection circuit includes a first terminal supplied with a first power supply potential and a second terminal supplied with a second power supply potential higher than the first power supply potential. In a moving image display mode, an image signal is input from the data line to the liquid crystal element through the transistor, and the first power supply potential is set at the first potential. In a still image display mode, supply of the image signal is stopped, and the first power supply potential is set at the second potential. The second potential is substantially the same as the minimum value of the image signal.

Abstract: A liquid crystal display device comprising a backlight and a pixel portion including first to 2n-th scan lines, wherein, in a first case of expressing a color image, first pixels controlled by the first to n-th scan lines are configured to express a first image using at least one of first to third hues supplied in a first rotating order, and second pixels controlled by the (n+1)-th to 2n-th scan lines are configured to express a second image using at least one of the first to third hues supplied in a second rotating order, wherein, in a second case of expressing a monochrome image, the first and second pixels controlled by the first to 2n-th scan lines are configured to express the monochrome image by external light reflected by the reflective pixel electrode, and wherein the first rotating order is different from the second rotating order.

Abstract: The liquid crystal display device includes a pixel portion including first and second regions and light sources. The first and second regions each include a liquid crystal element whose transmissivity is controlled in accordance with a voltage of an image signal and a transistor for controlling holding of the voltage, whose off-state current is extremely low. The light sources perform first and second drivings: lights whose hues are different from each other are sequentially supplied to the first region in a first rotating order and the lights are sequentially supplied to the second region in a second rotating order which is different from the first rotating order in the first driving; and a light having a single hue is supplied consecutively to one or both of the first and second regions in the second driving. The period for holding the voltage is different between the first and second drivings.

Abstract: An object is to provide a liquid crystal display device capable of image display according to an environment around the liquid crystal display device, e.g., in a bright environment or a dim environment. Another object is to provide a liquid crystal display device capable of displaying an image in both modes of a reflective mode in which external light is used as a light source and a transmissive mode in which a backlight is used. In order to achieve at least one of the above objects, a liquid crystal display device is provided with a region (a reflective region) where display is performed with reflection of incident light through a liquid crystal layer and a region (a transmissive region) where display is performed with transmission of light from a backlight and can switch the transmissive mode and the reflective mode.