Abstract: An imaging device that can obtain imaging data corresponding to high-resolution images in a short period of time is provided. The imaging device includes a pixel including a photoelectric conversion element and n (n is an integer more than 2 inclusive) retention circuits. The photoelectric conversion element and the n retention circuits are stacked. One electrode of the photoelectric conversion element is electrically connected to the first to n-th retention circuits. The retention circuits include OS transistors with an extremely low off-state current feature, and can retain imaging data for a long time. In the first to n-th periods, the imaging device obtains the first to n-th imaging data and retains it in the first to n-th retention circuits. Then, the first to n-th imaging data retained in the first to n-th retention circuits are read out. The read imaging data is output outside the imaging data through AD conversion.

Abstract: A low-power display device is provided. The display device is provided with a plurality of display portions. A data driver circuit and an addition circuit are provided to have a region overlapping with the display portion. First analog data is output from the data driver circuit in the case where first digital data consisting of a first digital value is input to the data driver circuit, whereas second analog data is output from the data driver circuit in the case where second digital data consisting of a second digital value is input to the data driver circuit. The addition circuit generates analog data corresponding to digital data that has a high-order bit that is the first digital value and a low-order bit that is the second digital value, by adding the second analog data to the first analog data. An output terminal of the data driver circuit is directly connected to an input terminal of the addition circuit without through an amplifier circuit.

Abstract: A display device with favorable display quality is provided. A display portion where a plurality of pixels is arranged in a matrix is divided into Region A and Region B, i.e., regions on the upstream side and the downstream side of a scanning direction. A signal line for supplying an image signal is provided in each of Region A and Region B. Region A and Region B adjoin each other such that a boundary line showing the boundary between the regions is bent. Bending the boundary line suppresses formation of a stripe in a boundary portion. For example, in a given column, the total number of pixels electrically connected to a signal line in Region A is made different from the total number of pixels electrically connected to a signal line in Region B.

Abstract: A display device with a narrower frame can be provided. In the display device, a first layer, a second layer, and a third layer are provided to be stacked. The first layer includes a gate driver circuit and a data driver circuit, the second layer includes a demultiplexer circuit, and the third layer includes a display portion. In the display portion, pixels are arranged in a matrix, an input terminal of the demultiplexer circuit is electrically connected to the data driver circuit, and an output terminal of the demultiplexer circuit is electrically connected to some of the pixels. The gate driver circuit and the data driver circuit are provided to include a region overlapping some of the pixels. The gate driver circuit and the data driver circuit have a region where they are not strictly separated from each other and overlap each other. Five or more gate driver circuits and five or more data driver circuits can be provided.

Abstract: An imaging device that can obtain imaging data corresponding to high-resolution images in a short period of time is provided. The imaging device includes a pixel including a photoelectric conversion element and n (n is an integer more than 2 inclusive) retention circuits. The photoelectric conversion element and the n retention circuits are stacked. One electrode of the photoelectric conversion element is electrically connected to the first to n-th retention circuits. The retention circuits include OS transistors with an extremely low off-state current feature, and can retain imaging data for a long time. In the first to n-th periods, the imaging device obtains the first to n-th imaging data and retains it in the first to n-th retention circuits. Then, the first to n-th imaging data retained in the first to n-th retention circuits are read out. The read imaging data is output outside the imaging data through AD conversion.

Abstract: A semiconductor device in which a transistor has the characteristic of low off-state current is provided. The transistor comprises an oxide semiconductor layer having a channel region whose channel width is smaller than 70 nm. A temporal change in off-state current of the transistor over time can be represented by Formula (a2). In Formula (a2), IOFF represents the off-state current, t represents time during which the transistor is off, ? and ? are constants, ? is a constant that satisfies 0<??1, and CS is a constant that represents load capacitance of a source or a drain.

Abstract: A high-definition display device is provided. A small display device is provided. In the display device, a first layer and a second layer are stacked and provided. The first layer includes a gate driver circuit and a source driver circuit, and the second layer includes a display portion. The gate driver circuit and the source driver circuit are provided to include a region overlapping with the display portion. The gate driver circuit and the source driver circuit have an overlap region where they are not strictly separated from each other. Five or more gate driver circuits and five or more source driver circuits can be provided.

Abstract: The reading accuracy of an imaging device is increased. Clear image capturing is performed even in the case where the luminance is high. A reading circuit of the imaging device includes an amplifier portion and a conversion portion. The amplifier portion amplifies a potential difference between a first signal and a second signal that are sequentially input and outputs the amplified difference to the conversion portion. The conversion portion converts the output potential of the amplifier portion into a digital value. The amplifier portion is reset on the basis of a first reference potential and the first signal and amplifies the potential difference on the basis of a second reference potential that is different from the first reference potential and the second signal.

Abstract: To provide an inexpensive display device. The display device includes a pixel and an IC chip. The pixel includes a first pixel circuit including a display element and a second pixel circuit including a light-receiving device. The one IC chip includes a control circuit, a data driver circuit, and a read circuit. The first and second pixel circuits are electrically connected to the read circuit. The control circuit has a function of controlling driving of the data driver circuit and the read circuit. The data driver circuit has a function of supplying image data to the first pixel circuit. The read circuit has a function of outputting a monitor signal corresponding to a monitor current when the monitor current flows through the first pixel circuit. The read circuit also has a function of outputting an imaging signal corresponding to imaging data acquired by the second pixel circuit.

Abstract: A display device with less display unevenness is provided. The display device includes a first layer and a second layer over the first layer; the first layer includes first circuits arranged in m rows and n columns; the second layer includes pixel blocks arranged in the m rows and the n columns; the pixel blocks each comprise pixels arranged in a rows and b columns; the pixel block includes a first wiring and a second wiring electrically connected to the pixel; the first wiring and the second wiring included in the pixel block in the i-th row and the j-th column are each electrically connected to the first circuit in the i-th row and the j-th column; the first wiring has a function of supplying an input signal from the first circuit to the pixel; and the second wiring has a function of supplying an output signal from the pixel to the first circuit.

Abstract: Common noise is reduced from light-receiving data. A display module includes a display apparatus and a reading circuit. Each of a first pixel and a second pixel adjacent to each other in the display apparatus includes a light-receiving element and a light-emitting element. The reading circuit includes a differential input circuit. Common noise generated when display data is supplied to a light-emitting element, for example, may affect a first light-receiving signal output by the first pixel and a second light-receiving signal output by the second pixel. A first current is generated using the first light-receiving signal and a ramp signal, and a second current is generated using the second light-receiving signal and a first potential. The differential input circuit is controlled so that the first current and the second current have the same current value, whereby common noise can be removed from the first light-receiving signal.

Abstract: A display device with high luminance is provided. A pixel includes a light-emitting device, a first transistor, a second transistor, a third transistor, a fourth transistor, a first capacitor, and a second capacitor. One electrode of the light-emitting device is electrically connected to one of a source and a drain of the first transistor. A gate of the first transistor is electrically connected to one electrode of the first capacitor and one of a source and a drain of the second transistor. The other of the source and the drain of the first transistor is electrically connected to one electrode of the second capacitor. One electrode of the second capacitor is electrically connected to a first wiring having a function of supplying a first potential. The other electrode of the second capacitor is electrically connected to the other electrode of the first capacitor, one of a source and a drain of the third transistor, and one of a source and a drain of the fourth transistor.

Abstract: A display device with favorable display quality is provided. A display portion where a plurality of pixels is arranged in a matrix is divided into Region A and Region B, i.e., regions on the upstream side and the downstream side of a scanning direction. A signal line for supplying an image signal is provided in each of Region A and Region B. Region A and Region B adjoin each other such that a boundary line showing the boundary between the regions is bent. Bending the boundary line suppresses formation of a stripe in a boundary portion. For example, in a given column, the total number of pixels electrically connected to a signal line in Region A is made different from the total number of pixels electrically connected to a signal line in Region B.

Abstract: A semiconductor device with a novel structure is provided. The semiconductor device includes a mixer circuit including a digital-analog converter circuit, a control circuit for controlling the digital-analog converter circuit, a power source control switch, and a plurality of Gilbert circuits. The plurality of Gilbert circuits each include an analog potential holding circuit for holding an analog potential output from the digital-analog converter circuit. The control circuit has a function of outputting a signal for controlling the analog potential holding circuit and the digital-analog converter circuit. The power source control switch has a function of stopping supply of a power source voltage to the control circuit in a period during which the analog potential held in the analog potential holding circuit is not updated. The analog potential holding circuit includes a first transistor. The first transistor includes a semiconductor layer including an oxide semiconductor in a channel formation region.

Abstract: A display device with high design flexibility that can be designed easily is provided. One embodiment of the present invention includes a first substrate (101) provided with a driver circuit including first and second pulse output circuits (91_1, 91_2), a second substrate (103) provided with a display unit (92) including a first pixel circuit including a first source wiring (SL_1) and a first contact portion (SC_1) and a second pixel circuit including a second source wiring (SL_2) adjacent to the first source wiring and a second contact portion (SC_2) electrically connected to the second source wiring, and a connection unit where the first and second substrates are electrically connected to each other.

Abstract: A high-definition display device is provided. A small display device is provided. In the display device, a first layer and a second layer are stacked and provided. The first layer includes a gate driver circuit and a source driver circuit, and the second layer includes a display portion. The gate driver circuit and the source driver circuit are provided to include a region overlapping with the display portion. The gate driver circuit and the source driver circuit have an overlap region where they are not strictly separated from each other. Five or more gate driver circuits and five or more source driver circuits can be provided.

Abstract: An imaging device having a motion detecting function and an image processing function is provided. The imaging device can detect a difference between a reference frame image and a comparative frame image, and can switch from a motion detecting mode to a normal image capturing mode when a significant difference is detected. A low-frame-rate operation in the motion detecting mode can reduce power consumption. Moreover, the imaging device has an image recognition function in combination with the motion detecting function, so that switching from the motion detecting mode to the normal image capturing mode can be performed when a particular image is recognized.

Abstract: A display device with a narrower frame can be provided. In the display device, a first layer, a second layer, and a third layer are provided to be stacked. The first layer includes a gate driver circuit and a data driver circuit, the second layer includes a demultiplexer circuit, and the third layer includes a display portion. In the display portion, pixels are arranged in a matrix, an input terminal of the demultiplexer circuit is electrically connected to the data driver circuit, and an output terminal of the demultiplexer circuit is electrically connected to some of the pixels. The gate driver circuit and the data driver circuit are provided to include a region overlapping some of the pixels. The gate driver circuit and the data driver circuit have a region where they are not strictly separated from each other and overlap each other. Five or more gate driver circuits and five or more data driver circuits can be provided.

Abstract: An imaging device capable of executing image processing is provided. A structure is employed in which a photoelectric conversion element, a first transistor, a second transistor, and an inverter circuit are included; one electrode of the photoelectric conversion element is electrically connected to one of a source and a drain of the first transistor; the other of the source and the drain of the first transistor is electrically connected to one of a source and a drain of the second transistor; the one of the source and the drain of the second transistor is electrically connected to an input terminal of the inverter circuit; and data obtained by photoelectric conversion is binarized and output.

Abstract: A display device with high resolution is provided. A display device with low power consumption is provided. A display device with high luminance is provided. A display device with a high aperture ratio is provided. The display device includes a first wiring, a second wiring, a third wiring, and a pixel electrode. The first wiring extends in a first direction and is supplied with a source signal. The second wiring extends in a second direction intersecting the first direction and is supplied with a gate signal. The third wiring is supplied with a constant potential. The first wiring and the pixel electrode overlap with each other with the third wiring therebetween.