US 11,726,249 B2
Optical retarder segments
Zhisheng Yun, Sammamish, WA (US); Michael L. Steiner, New Richmond, WI (US); Jo A. Etter, Kirkland, WA (US); Timothy L. Wong, St. Paul, MN (US); Gilles J. Benoit, Minneapolis, MN (US); John D. Le, Woodbury, MN (US); Erin A. McDowell, Afton, MN (US); and Susan L. Kent, Shorewood, MN (US)
Assigned to 3M INNOVATIVE PROPERTIES COMPANY, St. Paul, MN (US)
Filed by 3M INNOVATIVE PROPERTIES COMPANY, St. Paul, MN (US)
Filed on Jul. 26, 2022, as Appl. No. 17/873,420.
Application 17/873,420 is a division of application No. 16/648,698, granted, now 11,435,514, previously published as PCT/IB2018/058168, filed on Oct. 19, 2018.
Claims priority of provisional application 62/576,772, filed on Oct. 25, 2017.
Prior Publication US 2023/0115202 A1, Apr. 13, 2023
Int. Cl. G02B 5/30 (2006.01); G02B 27/01 (2006.01)
CPC G02B 5/3083 (2013.01) [G02B 27/0172 (2013.01); G02B 2027/0118 (2013.01)] 2 Claims
OG exemplary drawing
 
1. An optical system for displaying an object to a viewer comprising:
one or more optical lenses having at least one curved major surface;
a reflective polarizer disposed on and conforming to a first major surface of the one or more optical lenses, the reflective polarizer substantially reflecting light having a first polarization state and substantially transmitting light having an orthogonal polarization state at a predetermined wavelength in a range from about 400 nm to about 1000 nm;
a partial reflector disposed on and conforming to a different second major surface of the one or more optical lenses, the partial reflector having an average optical reflectance of at least 30% at the predetermined wavelength, the partial reflector and the reflective polarizer defining a folded optical cavity therebetween;
a first retarder layer disposed inside the folded optical cavity and having a substantially uniform retardance at the predetermined wavelength;
a second retarder layer disposed outside the folded optical cavity and having a substantially uniform retardance at the predetermined wavelength; and
a third retarder layer disposed outside the folded optical cavity and having a substantially non-uniform retardance at the predetermined wavelength,
such that when an image light ray emitted from a display at the predetermined wavelength is first incident on the reflective polarizer, the image light ray is substantially reflected with a first reflectance (ρ), and when the image light ray is second incident on the reflective polarizer, the image light ray is substantially transmitted with a first transmittance (τ), the third retarder layer increasing the first reflectance.