Receiving and transmitting coaxial laser detection system, adjusting method thereof and laser radar

The invention discloses a receiving and transmitting coaxial laser detection system, which comprises a laser, a detector, a lens and a prism, a light emitting point of the laser and a light receiving point of the detector are arranged on the same plane, the lens is arranged in front of the laser, the prism is arranged in front of the lens, and a light guide structure is arranged at the center of the prism. After being collimated by the lens, emergent light of the laser firstly emits to and completely passes through the light guide structure arranged on the prism and then emits to a detection area, return light is formed after encountering a detection object in the detection area, and the return light emitted to the prism and outside the outline of the light guide structure is refracted by the prism, then emits to the lens and is focused to a light receiving point of the detector through the lens. According to the laser detection system, on the basis that receiving and transmitting are coaxial, the light emitt