Abstract: A display device according to an aspect of the disclosure includes a pixel circuits, a scanning signal line, a data signal line, a first power supply voltage line, a second power supply voltage line, a scanning signal line drive circuit, a data signal line drive circuit, and a display control unit. The display control unit compares data values written in pixels in an n-th row corresponding to the selected scanning signal line with data values written in pixels in an (n?1)-th row which is one row prior to the n-th row of the selected scanning signal line, and corrects the data voltage corresponding to the pixels in the n-th row in a case where a difference between the data values is equal to or greater than a threshold value.

Abstract: In a display device that changes the number of light emissions per frame period, a display control circuit outputs a control signal specifying an emission period included in a frame period to an emission control line driver circuit. The emission control line driver circuit adds sequential delays to the control signal and thereby generates signals to be applied to the emission control lines. When leading and trailing frame periods have the same proportion of emission periods but include different numbers of emission periods, the leading and trailing frame periods are intervened by a transition frame period having a different proportion of emission periods from the leading frame period. This configuration prevents flickering caused by the changing of the number of light emissions per frame period.

Abstract: A display device is provided with: a display portion including a plurality of scanning lines, a plurality of data lines, and a plurality of pixel circuits; a scanning line drive circuit; and a data line drive circuit. The level of a data voltage applied to the data line decreases when a frame frequency is switched higher, and increases when the frame frequency is switched lower. This can prevent a display flicker when the frame frequency is switched. The level of the data voltage may change when the frame frequency is switched, and may return to its initial level over a plurality of frame periods. The timing of the control signal used to drive the display portion may change in accordance with the frame frequency to cause the length of the charging period of the pixel circuit to change in accordance with the frame frequency.

Abstract: A diamond tool which generates little vibrations, can be used in high temperature environments and can be produced with excellent yield has at least a shank portion (2) in contact with a diamond chip (1) and formed from a reaction-sintered silicon carbide material having a thermal expansion coefficient close to that of the diamond chip by using a diamond granule, and a method for producing the diamond tool which comprises contacting a diamond chip with an ingredient layer mixed with a diamond granule and a carbonaceous source, placing a metallic silicon powder on the surface of the layer, and then reaction-sintering it in vacuum or in a non-oxidizing atmosphere by heating, thereby forming a reaction-sintered silicon carbide material having a coefficient of thermal expansion close to that of a diamond chip, at least, in the shank portion at which a diamond chip is in contact.