Novel optical platform for transmission style smoke limit meter

The invention relates to a smoke measurement device for a diesel vehicle and in particular relates to a novel optical platform for a transmission style smoke limit meter. The optical platform comprises a fan, a detection pipeline, a gas chamber pipeline, a flue gas inlet pipe and a photoelectric detection unit. According to the optical platform, the airflow direction is changed under the condition that transmission and reception in the light path system are not influenced, the problem that the lens is directly polluted due to direct injection of the engine is greatly solved, the flue gas inlet pipe is of a bending angle structure, the pressure at the gas inlet is greatly buffered, the gas forms uniform airflow in the gas chamber pipeline and is discharged by virtue of the effect of an air curtain, uniform diffusion of the gas can be achieved, and the condition that the airflow directly impacts to inject to the surface of the lens is also avoided. A lens protection device can be conveniently dismounted and cleaned, and the use convenience and overall performance of the instrument are greatly improved.