1-to-100-micron surface height full-field 3D topography by use of the external reflectance versus height conversion method

Abstract

We propose “the external reflectance versus height conversion (ERHC) method” for measuring the full-field three-dimensional surface topography of a sample height from one micron to 100 micrometers. It is similar to the camera method, capturing images reflected and/or not from a prism by using a lens and a CCD. The reflectance of a point in the image can be converted to the height of the point. The method can obtain large-area full-field real-time three-dimensional measurement results and has the advantages of simple operation, low cost, and easy assembly. The measurement area is in the range of a few square millimeters for each time. The lateral and vertical resolutions are 2 and 0.1 micrometers, respectively, and the error is about 1% compared with the confocal microscope.