Patent ID: 8960922
Filing Date: 2015-02-24
Classification: G03B

Abstract:
1. A projector that performs light control by varying power level of a light source in response to a video signal, the projector comprising: a lamp including the light source; a light modulation device configured to modulate illumination light from the light source in response to image information; a cooling fan configured to cool the light source; and a control device configured to average samples of the power level of the lamp based on the video signal or a brightness level of the video signal acquired with respect to each unit time, and performs feedback control of a rotational speed of the cooling fan based on the average value, wherein: the control device is configured to: (1) calculate a first average value from a first number of samples in response to an increase in the power level or the brightness level, and (2) calculate a second average value different from the first average value from a second number of samples different from the first number of samples in response to a decrease in the power level or the brightness level, and the control device being configured to set the number of samples to be greater in response to an increase in the power level or the brightness level, and to set the number of samples to be smaller in response to a decrease in the power level or the brightness level.