Patent · US Expired

Testing method for a polarizing plate

US7154601B2 · kind B2 · utility

0Cited by
8References
5Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 22, 2004
Grant dateDec 26, 2006
Priority date
Expiry dateJul 23, 2024

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B27/28
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

The testing method for a polarizing plate includes the following two types of testing: a selected light beam passing through a filter, a polarizer, a concave lens and a filter, a mirror, a concave lens and finally to a sample of a polarizing plate; the sample is rotated along z-axis to ascertain that if there is any variation of shade in an optical domain, in order to differentiate defective samples from qualified ones. By applying the method, gooseflesh in the sample is ascertained by naked eyes easily while feeding; the checking result can be reflected to a factory owner. The test cost is low and requires only inexpensive instruments. Moreover, an additional processing of polarizing plate is needless.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.