Polarizing plates grading method
US7239382B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 19, 2004 |
| Grant date | Jul 3, 2007 |
| Priority date | — |
| Expiry date | Aug 20, 2025 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B5/3033
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
In a polarizing plate grading method a first measurement range A1 is chosen on a polarizing plate. After conducting an initial measurement by putting the polarizing plate under X1° C. for Y1 hours, the first measurement range is measured to obtain the maximum chromatic value Z1max (NIT,cd/m), and the minimum chromatic value Z1min. The minimum value is subtracted from the maximum value to obtain the net chromatic difference value W1. The temperature change measurement is conducted by putting the polarizing plate under X2° C. for Y2 hours and, then, the recovery measurement is conducted on the polarizing plate by putting the polarizing plate under X3° C. for Y3 hours. A first measurement range is measured to obtain the maximum chromatic value Z3max and the minimum chromatic value Z3min. The minimum chromatic value is subtracted from the maximum chromatic value to obtain the net chromatic difference value W3. The polarizing plate grading index Q is obtained by dividing the value obtained from subtracting the net chromatic difference value W1 obtained in the initial measurement from the net chromatic difference value W3 obtained in the recovery measurement, by the net chromatic differe…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.