PROJECTION SYSTEM

A projection system including at least a light source, at least a dichroic filter element and a light-adjusting diaphragm element is provided. The light source is configured to emit a first color light having a spectrum of a first wavelength range and a second color light having a spectrum of a second wavelength range. The dichroic filter element is configured to reflect or allow the first color light and the second color light to pass through. The light-adjusting diaphragm element has a filter and is located on an optical path generated after the first color light and the second color light are split. The first color light passes through the filter, which blocks at least a part of the energy of the second color light, such that a transmittance of the spectrum of the first wavelength range is greater than that of the spectrum of the second wavelength range.