Abstract: A cooling structure of an on-vehicle projector, includes: a projector including: a light source; an image projection part configured to project an image based on the light emitted from the light source and an image signal; and first and second vent holes configured to ventilate the internal space, in which the light source is arranged, with the outside; and an air introduction part configured to introduce conditioned air, sent from an air conditioner mounted in a vehicle, to the internal space through the first vent hole.

Abstract: An illumination device includes: an elongated light guide; a first light source; a second light source; and a controller. A first increase beginning time point at which the brightness of the first light source begins to increase from zero is prior to a second increase beginning time point at which the brightness of the second light source begins to increase from zero. A first increase finish time point at which the brightness of the first light source finishes increasing to the first set brightness is simultaneous with or prior to a second increase finish time point at which the brightness of the second light source finishes increasing to the second set brightness. A time from the first increase beginning time point to the second increase finish time point is not more than 0.2 seconds.

Abstract: A steering wheel includes an indicator. The indicator includes a light source that emits light and a light guide. The light guide includes an outer surface and an end opposing the light source. The light emitted from the light source enters the end of the light guide, and some of the light is emitted from the outer surface.

Abstract: An illumination device includes: an elongated light guide; a first light source; a second light source; and a controller. A first increase beginning time point at which the brightness of the first light source begins to increase from zero is prior to a second increase beginning time point at which the brightness of the second light source begins to increase from zero. A first increase finish time point at which the brightness of the first light source finishes increasing to the first set brightness is simultaneous with or prior to a second increase finish time point at which the brightness of the second light source finishes increasing to the second set brightness. A time from the first increase beginning time point to the second increase finish time point is not more than 0.2 seconds.

Abstract: A steering wheel includes an indicator. The indicator includes a light source that emits light and a light guide. The light guide includes an outer surface and an end opposing the light source. The light emitted from the light source enters the end of the light guide, and some of the light is emitted from the outer surface.

Abstract: A steering wheel includes an indicator including a light source, a metal core including an outer surface, a base that covers the metal core, and a heat releasing portion arranged outward from the outer surface of the metal core. The heat releasing portion is thermally connected to the light source and the outer surface of the metal core. The heat releasing portion is formed from a material having a higher thermal conductivity than the base and has a larger surface area than the light source.