Patent ID: 8085409
Filing Date: 2011-12-27
Classification: G01B

Abstract:
1. A surface profile measuring apparatus, comprising: a light projecting section for projecting light onto a surface of a sample; a light receiving section for receiving light reflected from the surface of the sample; an aperture switching section configured to select an aperture having a predetermined cross-sectional area and causing the projected light to pass through the aperture prior to being projected onto the surface of the sample; the aperture switching section configured to select an aperture of reduced size when the sample is curved, wherein the reduced aperture size causes a reduction in a cross-sectional area of light projected onto the surface of the sample so as to reduce divergence of the light reflected from the surface; the aperture switching section configured to select an aperture of increased sized when the sample has an uneven or fine surface roughness, wherein the increased aperture size causes an increase in a cross-sectional area of light projected onto the surface of the sample so as to reduce variations in the light reflected from the surface; and a computing section configured to measure a surface profile of the sample based on an output from the light receiving section and based on the aperture selected by the aperture switching section.