Abstract: A wireless communication apparatus which communicates with at least one wireless station apparatus by utilizing EDCA mechanism includes the following elements. A first channel state determining unit determines a usage state of a communication channel used between the wireless communication apparatus and the wireless station apparatus in a contention period of the communication channel. A first terminal occupation time calculating unit calculates, on the basis of the usage state, a different-terminal occupation time in the contention period of the communication channel. A first traffic measuring unit measures an amount of data received from the wireless station apparatus in the different-terminal occupation time. A first parameter adjusting unit adjusts an EDCA parameter set used in the EDCA mechanism, on the basis of the different-terminal occupation time and the amount of received data. A parameter updating unit updates the EDCA parameter set to an adjusted EDCA parameter set.

Abstract: A projector includes a plurality of light sources; a controller which controls dimming of the plurality of light sources individually; a light modulator which synthesizes light emitted from each of the plurality of light sources to generate synthetic light, and modulates the synthetic light to generate an optical image; and a projecting optical system which projects the optical image generated by the light modulator. The plurality of light sources include a first light source and a second light source, and when the controller causes the plurality of light sources to emit dimmed light, the controller causes the first light source to emit light with supplied power greater than or equal to 50% of rated power and causes the second light source to emit light with supplied power less than 50% of the rated power or turn off.