公开(公告)号：US20150219441A1

公开(公告)日：2015-08-06

申请号：US14612370

申请日：2015-02-03

Applicant: MITUTOYO CORPORATION

Inventor： Han HAITJEMA ,  Frans de NOOIJ ,  Lukasz REDLARSKI

IPC: G01B11/06 ,  G02B21/36

CPC classification number: G01B11/0608 ,  G01B11/2513 ,  G01B11/2527 ,  G02B21/364

Abstract: In a method and apparatus for determining the height of a plurality of spatial positions on a surface of a specimen, a light beam is projected on the surface. The light beam has a sinusoidal spatial pattern in at least two directions perpendicular to an optical axis of the light beam, and which is moved to different spatial pattern positions. The surface is scanned along the optical axis in different scanning positions. A fixed relationship between a moving distance between subsequent spatial pattern positions, and a scanning distance between subsequent scanning positions exists. The light reflected by the surface is detected in scanning positions with the spatial pattern having corresponding spatial pattern positions. From the detected light for each spatial position of the surface, an envelope curve of intensity values corresponding to scanning positions is determined. A maximum of the envelope curve and its corresponding scanning position being representative of the height of the spatial position of the surface is selected. The spatial pattern is moved in a sequence of 2n steps (n>2) in a first and a second spatial direction over a distance of ¼ and 1/n pattern wavelength, respectively.

Abstract translation: 在用于确定样本表面上的多个空间位置的高度的方法和装置中，光束被投射在表面上。 光束在与光束的光轴垂直的至少两个方向上具有正弦空间图案，并且移动到不同的空间图案位置。 沿不同扫描位置的光轴扫描表面。 存在随后的空间图案位置之间的移动距离与后续扫描位置之间的扫描距离之间的固定关系。 在具有对应的空间图案位置的空间图案的扫描位置中检测由表面反射的光。 从针对表面的每个空间位置的检测光，确定与扫描位置对应的强度值的包络线。 选择最大包络线及其对应的扫描位置代表表面空间位置的高度。 空间图案分别在1/4和1 / n图案波长的距离上沿第一和第二空间方向以2n个步长（n> 2）的顺序移动。