提出一种使用自聚焦透镜构成的光强度调制的光学位移测量原理,利用发光二极管作光源,光从第一根自聚焦透镜发出,然后受到反射镜的反射而进入第二根自聚焦透镜,当反射镜有小位移时,进入第二根自聚焦透镜的光强度被调制,用光电管检测光强度的变化,可以确定位移的大小。根据该原理,位移分辨率的理论值可达10-9m,实验测量的位移分辨率为10-8m。该原理亦可用于测量小振动和压力等量。

A novel mothod of intensity modulated optic displacement measurement is described. A LED is used as source. The ray projects from the first SELFOC lens, then is reflected by the mirror and enters into second SELFOC lens. When the mirror has some little displacement, the ray entering the second SELFOC lens is modulated. The value of displacement is determined according to the change of light intensity with photocell. A resolution of 1×10-9 m is attainable with this metering device. The principle can be also used in the measurement of pressure and vibration.