US Patent 11143944 Projection device and calibration method thereof

A projection device includes a light source, an optical engine and a controller. The light source provides a light beam according to a setting current. The optical engine includes a light combining module, an imaging module and a projection lens. The light combining module receives the light beam to generate an illumination beam. The imaging module includes a prism, a digital micromirror device and a light sensor. The prism transmits a portion of the illumination beam to the light sensor. The digital micromirror device converts the other portion of the illumination light beam into an image beam. The light sensor disposed between the prism and the digital micromirror device receives the portion of the illumination beam to generate a brightness data. The projection lens projects the image beam. The controller dynamically adjusts the setting current to calibrate a color point of the light beam according to the brightness data.