Display device and image capturing device
A display device includes signal supply circuit having N blocks and data supply circuit for supplying data to the N blocks. Each block includes holding block having k data holders for supply signals to k columns, and scanning circuit block for sequentially selecting the k data holders to receive data from the data supply circuit. The scanning circuit block includes k-stage shift register formed from k registers. Scanning circuit is formed by N scanning circuit blocks each arranged in one of the N blocks, and sequentially selects the N holding blocks each arranged in one of the N blocks to sequentially select the k data holders of each selected holding block to receive data. In response to output from i-th register of n-th block, the data supply circuit sets (n+1)-th block in operation-enabled state.
1. A display device comprising:
a plurality of pixels arranged so as to form a plurality of rows and a plurality of columns;
a row selection circuit configured to select a row among the plurality of rows; and
a signal supply circuit configured to supply a signal to each pixel of the row selected from the plurality of pixels by the row selection circuit,
wherein the signal supply circuit includes N blocks and a data supply circuit configured to supply data to the N blocks,
wherein each of the N blocks includes (a) a holding block including k data holders configured to supply signals to k columns of the plurality of columns, and (b) a scanning circuit block configured to sequentially select the k data holders to receive data from the data supply circuit, and the scanning circuit block includes a k-stage shift register formed from k registers which are connected in series,
wherein a scanning circuit is formed by connecting, in series, N scanning circuit blocks, each of which is arranged in the corresponding one of the N blocks, and the scanning circuit sequentially selects the N holding blocks, each of which is arranged in the corresponding one of the N blocks, to sequentially select the k data holders of each selected holding block to receive data,
wherein for i<k, in response to an output from an i-th register of an n-th block from the first block, of the N blocks, in the scanning direction of the scanning circuit, the data supply circuit sets an (n+1)-th block from the first block of the N blocks in an operation-enabled state, and
wherein for j<k, the data supply circuit sets an (n−1)-th block from the first block of the N blocks in an operation-suppressed state in response to an output from a j-th register of the n-th block.
2. The device according to claim 1 , wherein in response to the output from the i-th register of the n-th block, the data supply circuit starts supplying data to the (n+1)-th block.
3. The device according to claim 2 , wherein for j<k, data supply to an (n−1)-th block from the first block of the N blocks is completed in response to an output from a j-th register of the n-th block.
4. The device according to claim 3 , wherein the data supply circuit includes N drive circuits corresponding to the N blocks, respectively, and each of the N drive circuits includes a mask circuit configured to output data corresponding to input data in an enabled state and to output a fixed value in a disabled state, and
wherein an n-th drive circuit corresponding to the n-th block causes the mask circuit of the n-th drive circuit to shift from the disabled state to the enabled state in response to an output from an i-th register of the (n−1)-th block and causes the mask circuit of the n-th drive circuit to shift from the enabled state to the disabled state in response to an output from a j-th register of the (n+1)-th block.
5. The device according to claim 2 , wherein in response to the output from the i-th register of the n-th block, the data supply circuit starts an operation to supply a clock signal, used to cause the scanning circuit to operate, to the (n+1)-th block.
6. The device according to claim 5 , wherein for j<k, the data supply circuit completes the operation to supply the clock signal to an (n−1)-th block in response to an output from a j-th register of the n-th block.
7. The device according to claim 6 , wherein the data supply circuit includes N drive circuits corresponding to the N blocks, respectively, and each of the N drive circuits includes a mask circuit configured to output the clock signal in accordance with a reference clock signal in an enabled state and to output a fixed value in a disabled state, and
wherein the n-th drive circuit corresponding to the n-th block causes the mask circuit of the n-th drive circuit to shift from the disabled state to the enabled state in response to an output from an i-th register of the (n−1)-th block and causes the mask circuit of the n-th circuit to shift from the enabled state to the disabled state in response to an output from a j-th register of the (n+1)-th block.
8. The device according to claim 1 , wherein the signal supply circuit includes a holder array configured to receive, at once, data from each of the N holding blocks arranged in the N blocks and a DAC array configured to convert data provided from the holder array into an analog signal.
9. An image capturing device comprising:
an image capturing unit; and
a display device defined in claim 1 and formed as a display unit configured to display an image obtained from an image captured by the image capturing unit.