Patent ID: 8911092

Claim:
An illuminating device for emitting light onto a light modulating element that forms an image in accordance with a modulation signal and irradiates a target to be illuminated with light, the illuminating device comprising: a substrate on which equal to or more than two phosphors that emit light with exciting light are formed in a band-like form along a predetermined direction; equal to or more than two light collecting units that are arranged for the respective equal to or more than two phosphors, and collect light components emitted from the respective equal to or more than two phosphors; equal to or more than two light sources; and a driving unit that drives the substrate in the predetermined direction, wherein the equal to or more than two phosphors are formed on the substrate on concentric circles, the driving unit rotationally drives the substrate about center of the concentric circles as an axis, and a respective light from the equal to or more than two light sources are irradiated into respective different circles that are in the concentric circle.