讨论用CCD作尺寸自动检测的问题

Discussed on Problems Using CCD for Size Measurement

本文讨论应用 CCD 作为尺寸自动检测中的三个问题:1.在直接测量中工件到 CCD 距离 L 和光束孔径角 u 及节距 q 之间的关系;2.远心光路中物体移动时像平面上光斑直径的表达式,讨论脉冲当量、允许物距误差、光束孔径角的关系;3.讨论远心投影物镜像差和 CCD 节距的关系,给出远心投影物镜校正像差的依据。

Follwing problems in application of CCD to automatic sizc test are discussed:1)The relation between the distance L from workpiece to CCD,the aperture angle u of light beam and the pitch q of CCD is discussed in the direct measurement.2)The expression of spotdiameter on the image plane when the object moves in a telecentric system.The relation between pulse equivalent,tolerance of object distance and aperture angle of light beam is discussed.3)The relation betw- een aberrations of the telecentric projection objective and the pitch CCD is discussed. The criterion of correcting aberrations in the telecentric projection objective is also given.