The optimeter is widely used to precisely measure external size of workpiece by comparison with a gauge block or standard part.

本仪器是一般是用标准器（）以比较法测工件寸。

The optimeter is widely used to precisely measure external size ofworkpiece by comparison with a gauge block or standard part.

本仪器是一种采用或标准零件与试件相比较方式测物体外形寸仪器。