Projection type video display

Abstract

A system control circuit is provided with a table storing portion. In the table storing portion, a table for a positioned-on-a-floor mode and a hung-from-a-ceiling mode, a table for upwardly-positioned, and a table for downwardly-positioned are stored. On each table, temperature of outside air and voltage supplied to each fan power supply are corresponded. In receipt of information indicating a positioned-on-a-floor state (angle=zero degrees) from an attitude detection sensor, the system control circuit selects the table for a positioned-on-a-floor mode and a hung-from-a-ceiling mode. In addition, the system control circuit obtains measured temperature data from a temperature sensor, and applies this measured temperature data to the selection table as a read-out address. As a result, voltage values regarding each fan power supply are read out from the selection table. The system control circuit instructs each fan power supply to drive the fans based on the read-out voltage values.

Dependencies are inferred from the claim text.