Disclosed are novel reflective films having symmetrical reflection characteristics on the upper and lower surfaces thereof. Preferably, such films are made from cholesteric liquid crystal (CLC) material, wherein the pitch of the helices of the liquid crystal molecules therein varies along the thickness dimension (i.e. transverse to the surface) of the film. Depending on the final spiral structure of the materials utilized, the CLC circularly polarizing film materials reflect either left-handed or right-handed circularly polarized light. In a first illustrative embodiment, the CLC film has a laminated construction in order that both the upper and lower surfaces thereof have substantially the same reflection characteristics over its tuned reflection band. In second illustrative embodiment, the CLC film has a laminated construction in order that both the upper and lower surfaces thereof have substantially the same reflection characteristics over its broadband reflection band. By virtue of their circularly polarizing reflection characteristics, the CLC films of the present invention can be used to form polarization-encoded spatially multiplexed images (SMI) on radiation absorbing surfaces, coloring media with high brightness characteristics, CLC-based toner 2-D and 3-D xerographic printing processes, and the like.

 
Web www.patentalert.com

< Thin film coater and coating method

< Liquid crystal display device in which the light length, polarizing axis, and alignment direction are related

> Transmissive optical polarizing filters designed to maximize a desired portion of a spectral output

> Liquid crystal display having wide viewing angle range

~ 00033