Claims
- 1. An optical cell comprising liquid crystal means comprising one or more compounds selected from the group consisting of compounds of formula ##SPC11##
- wherein R is straight-chain lower alkyl of 4 to 8 carbon atoms or straight-chain lower alkoxy of 5 to 8 carbon atoms,
- disposed between two plate means at least one of which plate means is transparent; means for controlling the optical activity of the cell; and said liquid crystal means having a helical structure in the direction perpendicular to the plate means and the surfaces of the plate means being wall oriented.
Priority Claims (2)
Number |
Date |
Country |
Kind |
2586/72 |
Feb 1972 |
CH |
|
920/73 |
Jan 1973 |
CH |
|
Parent Case Info
This is a division of application Ser. No. 334,291, filed Feb. 21, 1973, now U.S. Pat. No. 3,923,857.
US Referenced Citations (1)
Number |
Name |
Date |
Kind |
3795436 |
Boller et al. |
Mar 1974 |
|
Divisions (1)
|
Number |
Date |
Country |
Parent |
334291 |
Feb 1973 |
|