我们把百分表原有测头换成有机玻璃的测头2,并装入自制的铜套管1内(见图),套管的下端孔径φ与被测透镜的外径相同,以α-α面为基面,用一圆平面调整百分表零位。当在孔径φ内放入被测透镜(图中虚线)后,百分表的有机玻璃测头便与透镜的凹面中心接触(图中的虚线),百分表给出一个读数。根据 We put the original dial probe original plexiglass probe 2, and into the home-made copper tube 1 (see Figure), the lower end of the tube diameter φ and the lens diameter measured the same as α -α surface as the base surface, with a round plane to adjust the dial indicator zero. When the lens to be measured (dotted line in the figure) is placed inside the aperture φ, the plexiglass probe of the dial indicator comes in contact with the concave center of the lens (dotted line in the figure). The dial indicator gives a reading. according to