It is made possible to provide a stereoscopic image display apparatus capable of preventing the stereoscopic display characteristics from being degraded even if the locus of light rays between the lens and the two-dimensional display device becomes long. A scale grating 32A is formed in the rotary scale plate with a shape and size that correspond to a light image of the object grating 31A incident on the surface thereof. The LED chip is between the light exit surface adjuster and the substrate, and an overlap area between the LED chip and the light-transmitting surface is smaller than an overall area of the LED chip. If the MN exists under the AR, the IP packet is transmitted to the MN. The at least one second fan is disposed on the cover body and matches the at least one air outlet.