A display of various types of information on a subdisplay provided to a main body of a projector can be maintained even after supply of power source is stopped. According to a representative embodiment, included are: a power source connection unit connecting a power supply line for supplying, from outside, power used in a projection type image display apparatus; a nonvolatile display device provided separately from an image projection unit and displaying at least character information; and a processing unit displaying information on one or more predetermined items on the nonvolatile display device, and a state of displaying information on the nonvolatile display device is maintained even in a state where the power supply line is not connected to the power source connection unit.