The three-dimensional image system comprises a light source, a modulator, a first optical splitting device, a second optical splitting device, an optical sub-module, a photo-sensitive device and a signal processing module; the modulator is connected to the light source for modulating light source output through a frequency scanning signal; a first optical splitting device is connected to the light source and is used for splitting light coming from the light source into a first light path light output and a second light path light output; the second optical splitting device is connected to the first optical splitting device for splitting the second light path light output into multiple optical signals through light splitting; the optical sub-module is used for collecting light which passes through an object or is reflected from the object and coupling the collected light into a light combining device; the photo-sensitive device is connected to the light combining device for sensing the light output of the light combining device and converting the light output to multiple electric signals; and the signal processing module is connected to the photo-sensitive device for extracting three-dimensional information from the electric signal.