前向散射能见度仪测量前向散射光强度，确定大气的消光系数，进而获得大气的能见度值。基于上述原理，考虑雾天大气散射特性，研制了一台前向散射能见度仪样机。通过样机室外雾天散射光强测量值与实地能见度值的比较，给出之间的修正计算公式。样机还在外场与国外同类仪器进行了实测数据对比实验。

The intensity of forward-scattered light is measured by the forward-scattering visibility sensor,which determines the extinction coefficient of the air, then the visibility can be obtained. Based on the described principle and considering the characters of the light scattering in fog, a forward-scattering visibility sensor is constructed. A modified calculation formula between the measured intensity and visibility is given by comparing the intensity measured outside in fog and visibility recorded. Comparison test on the constructed visibility and a foreign one is also carried out outside in fog.