Patent ID: 8506092

Claim:
A projector that switches video images between right-eye and left-eye video images at predetermined switching timings and alternately outputs the right-eye and left-eye video images, the projector comprising: a discharge lamp; a discharge lamp driver that supplies the discharge lamp with a drive current for driving the discharge lamp; a voltage detector that detects a drive voltage for driving the discharge lamp; and a controller that controls the discharge lamp driver, wherein a period sandwiched between temporally adjacent ones of the switching timings starts with a first period and ends with a second period, the controller carries out a first control process in which the discharge lamp driver is so controlled that an absolute magnitude of the drive current in the first period is smaller than that in the second period and that an AC current is supplied as the drive current to the discharge lamp in the second period, and the first control process includes a first electric power control process in which first average drive electric power is determined based on the drive voltage detected by the voltage detector and the discharge lamp driver is controlled to supply the drive current to the discharge lamp in such a way that average drive electric power is set at the first average drive electric power.