Westerman, Hattori, Daniels & Adrian, LLP
Method for preparing synthetic quartz glass substrate
A synthetic quartz glass substrate is prepared by furnishing a synthetic quartz glass block, coating an arbitrary surface and an opposite surface of the block with a liquid having a transmittance of at least 99.0%/mm at the wavelength of birefringence measurement, measuring the birefringence of the block by letting light enter one coated surface and exit the other coated surface, and sorting the block to an acceptable or unacceptable group, based on the measured birefringence value.
SHIN-ETSU CHEMICAL CO., LTD.
B G C B C G
B28D G01N C03C B07C C03C G01N
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Daijitsu Masaki Kazuo Hisashi
Harada Takeuchi Shirota Yagi