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

是一般是用（如量块）以比较法测量工件的尺。

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

是一种采用量块或零件与试件相比较的方式测量物体外形尺的。