Patent ID: 11874576
Assignee: REALD SPARK, LLC
Field: Optics (Instruments)
Classification: CPC G | IPC F  G

Claim 21:
22. A display device according to claim 19, wherein the plural polar control retarders further include:
a passive retarder which has an optical axis perpendicular to the plane of the passive retarder, the passive retarder having a retardance for light of a wavelength of 550 nm in a range from −300 nm to −900 nm, preferably in a range from −450 nm to −800 nm and most preferably in a range from −500 nm to −725 nm; or
a pair of passive retarders which have optical axes in the plane of the pair of passive retarders that are crossed, each retarder of the pair of passive retarders having a retardance for light of a wavelength of 550 nm in a range from 300 nm to 800 nm, preferably in a range from 500 nm to 700 nm and most preferably in a range from 550 nm to 675 nm.