US Patent 11156906 Projector with air inlets to cool light emitting module

A projector comprises a casing, a projection lens module and a light emitting module. The casing comprises a first air inlet and an air outlet. The projection lens module is disposed in the casing and adjacent to the first air inlet. The light emitting module is disposed in the casing and adjacent to the air outlet. The casing comprises a rear cover. The rear cover comprises a second air inlet, the second air inlet corresponds to the light emitting module. A first airflow flows into the casing from the first air inlet to dissipate heat from the projection lens module and the light emitting module, and then flows out of the air outlet. A second airflow flows into the casing from the second air inlet to dissipate heat from the light emitting module, and then flows out of the air outlet.