Illuminating device, exposure system and photoetching equipment

The embodiment of the invention discloses an illuminating device, an exposure system and photoetching equipment. The illuminating device comprises a light source and a light uniformizing unit and a relay unit which are sequentially arranged on a light emitting path of the light source, the light uniformizing unit is used for uniformizing emitted light beams of the light source, and the relay unitis used for amplifying the view field of the emitted light of the light uniformizing unit; and the illuminating device further comprises a uniformity adjusting unit arranged in the light uniformizingunit or the relay unit, and an adjustable first included angle is formed between a plane where the uniformity adjusting unit is located and a plane perpendicular to the optical axis of the emitted light beams, so that the illuminating device forms a uniformly-distributed illuminating image plane. According to the technical scheme of the embodiment of the invention, by arranging the uniformity adjusting unit, the uniformity