Receiving and emitting light module

The utility model relates to a light receiving and emitting module, which comprises a light emitting sub-module and a light receiving sub-module, and is characterized in that a first multimode optical fiber, a single-mode optical fiber and a second multimode optical fiber are arranged between the light emitting sub-module and the light receiving sub-module, the first multimode optical fiber is used for guiding light emitted by the light emitting sub-module to the single-mode optical fiber, and the second multimode optical fiber is used for guiding light emitted by the light receiving sub-module to the single-mode optical fiber. The single-mode optical fiber is used for guiding the light from the first multi-mode optical fiber to the second multi-mode optical fiber, and the second multi-mode optical fiber is used for guiding the light from the single-mode optical fiber to the light receiving sub-module. According to the utility model, a transmission mode that the first multimode optical fiber is connected with