Method and apparatus to fold optics in tools for measuring shape and/or thickness of a large and thin substrate

• Main Authors: An Zeng Andrew, Zhang Yi, Goodman Frederick Arnold, Wang Chunhai, Huang Chunsheng, Tang Shouhong
• Format: Patent
• Language: English
• Published: 27.02.2018
• Subjects: ELECTRIC COMMUNICATION TECHNIQUE; ELECTRICITY; MEASURING; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS; MEASURING LENGTH, THICKNESS OR SIMILAR LINEARDIMENSIONS; OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICS; PHYSICS; PICTORIAL COMMUNICATION, e.g. TELEVISION; TESTING

A semiconductor measuring tool has a folding mirror configuration that directs a light beam to pass the same space multiple times to reduce the size and footprint. Furthermore, the folding mirrors may reflect the light beam at less than forty-five degrees; thereby allowing for smaller folding mirror...