US 12,235,456 B2
Folded optics for a head mounted display
Joshua Hudman, Bellevue, WA (US); and Doug VanderWel, Kent, WA (US)
Assigned to Valve Corporation, Bellevue, WA (US)
Filed by Valve Corporation, Bellevue, WA (US)
Filed on Mar. 13, 2024, as Appl. No. 18/603,690.
Claims priority of provisional application 63/490,170, filed on Mar. 14, 2023.
Prior Publication US 2024/0310633 A1, Sep. 19, 2024
Int. Cl. G02B 27/01 (2006.01); G02B 5/30 (2006.01); G02B 27/00 (2006.01); G02B 27/09 (2006.01)
CPC G02B 27/0172 (2013.01) [G02B 5/3083 (2013.01); G02B 27/0093 (2013.01); G02B 27/0955 (2013.01); G02B 2027/014 (2013.01)] 20 Claims
OG exemplary drawing
 
1. An apparatus for folded optics in a head-mounted display, the apparatus comprising:
a display of a virtual-reality device;
a lens system arranged to focus light from the display to a user's eye of the virtual-reality device, the lens system comprising:
a first lens, wherein:
the first lens has a first surface and a second surface;
the second surface is opposite the first surface;
the first surface is curved;
the first lens has a first thickness profile; and
the first thickness profile is measured between the first surface and the second surface of the first lens; and
a second lens, wherein:
the second lens has a third surface and a fourth surface;
the fourth surface is opposite the third surface;
the fourth surface is curved;
the second lens has a second thickness profile;
the second thickness profile is measured between the third surface and the fourth surface;
the second thickness profile is the same as the first thickness profile; and
the second lens is symmetrically arranged in relation to the first lens so that the third surface is closer to the second surface than the first surface, and the second surface is closer to the third surface than the fourth surface;
a partial reflector between the first lens and the second lens;
a first waveplate between the partial reflector and the first lens, wherein:
the first waveplate is a quarter waveplate; and
the first waveplate is adhered to the second surface of the first lens;
a second waveplate between the partial reflector and the second lens, wherein:
the second waveplate is a quarter waveplate; and
the second waveplate has a fast axis parallel to a fast axis of the first waveplate so that the fast axis of the second waveplate is oriented in a similar direction as the fast axis of the first waveplate;
a first reflective polarizer on the first surface of the first surface and arranged so that the first lens is between the first waveplate and the first reflective polarizer; and
a second reflective polarizer on the fourth surface of the second lens and arranged so that the second lens is between the second waveplate and the second reflective polarizer.