Light source module, sensing device and method for generating superposition structured patterns

A light source module adapted to provide a superposition structured pattern and comprising:

• a light emitting device adapted to provide a light beam;
• a light guiding element disposed on a transmission path of the light beam, the light guiding element comprising a polarizing beam splitter to separate the light beam into a first light beam and a second light beam;
• a first diffractive element disposed on a transmission path of the first light beam to convert the first light beam into a first structured light;
• and
• a second diffractive element disposed on a transmission path of the second light beam to convert the second light beam into a second structured light, wherein a polarization state of the first light beam is different from a polarization state of the second light beam, the first structured light and the second structured light are projected in a projection region, and overlapped and imaged as the superposition structured pattern, the projection region having a plurality of sub-projection regions arranged in a matrix and adjacent to each other, the superposition structured pattern having different pattern distributions in each of the plurality of sub-projection regions.