Patent ID: 9201293
Filing Date: 2015-12-01
Classification: G03B,H04N

Abstract:
1. A projection display apparatus projecting an image light based on an image, comprising: a display element that displays said image; a lamp that illuminates said display element to cause said display element to emit said image light; a variable light intensity element that allows the light emitted from said lamp to pass therethrough, the intensity of light passing through the variable light intensity element being variable; and a light intensity controller that determines whether said display element is at an image mute state in which a full-black image is display, or at a normal lighting state other than said image mute state, and when said display element is at said image mute state, reduces the amount of power supplied to said lamp, and also decreases the intensity of light that passes through said variable light intensity element, wherein when said light intensity controller detects that said lamp power is smaller than a predetermined value for a certain period of time or longer under said image mute state, said light intensity controller increases the lamp power to said predetermined value, and after elapse of a predetermined period of time, reinstates the lamp power to a value which was prior to the time when the lamp power was increased to said predetermined value, and wherein a value of said lamp power at a time when said display element is at said image mute state, is lower than a rated power of said lamp.