Abstract: In various embodiments, a pancake lens block including a shaped reflective polarizer is described. In an embodiment, the shaped reflective polarizer may include an optical element that may be configured to transmit at least a portion of light from a light source. Further, the shaped reflective polarizer may include a wire-grid polarizer that comprises (i) a bolstering substrate, (ii) a wire-grid substrate coupled to the bolstering substrate, and (iii) wire-grids disposed on the wire-grid substrate. The shaped reflective polarizer may be spaced from the optical element by a distance, which may include a cavity filled with a material (such as air or a nanovoided material).

Abstract: In various embodiments, a pancake lens block (e.g., a reverse order crossed pancake lens block) including azimuthal compensation may include an optical element configured to transmit at least a portion of light emitted by an electronic display. The pancake lens block may further include an azimuthal compensator coupled to a surface of the optical element. Moreover, the azimuthal compensator may include a uniaxial birefringent material, and the azimuthal compensator may be configured to reduce an optical effect of stress birefringence in the optical element.

Abstract: In various embodiments, a pancake lens block may include (i) a first compound retarder comprising a first plurality of retarders oriented to a plurality of first axes of orientation, respectively, where the first compound retarder is configured to selectively transmit a portion of the emitted light, (ii) a partial reflector that receives the portion of emitted light from the first compound retarder and transmits the portion of the emitted light, (iii) a second compound retarder comprising a second plurality of retarders oriented to a plurality of second axes of orientation that are substantially orthogonal to the respective plurality of first axes of orientation, and (iv) a reflective polarizer configured to reflect the portion of the emitted light selectively transmitted by the second compound retarder back to the second compound retarder.

Abstract: In various embodiments, a reverse-order crossed pancake lens block having an index gradient structure may include an optical element configured to transmit at least a portion of radiation from a radiation source. Moreover, the pancake lens block may include an index-gradient structure that is spaced at a distance from the optical element, the distance configured to provide an optical path length in the pancake lens block. The index-gradient structure may be configured to provide an anti-reflective property to at least one surface of the optical element.

Abstract: In various embodiments, a pancake lens block including a shaped reflective polarizer is described. In an embodiment, the shaped reflective polarizer may include an optical element that may be configured to transmit at least a portion of light from a light source. Further, the shaped reflective polarizer may include a wire-grid polarizer that comprises (i) a bolstering substrate, (ii) a wire-grid substrate coupled to the bolstering substrate, and (iii) wire-grids disposed on the wire-grid substrate. The shaped reflective polarizer may be spaced from the optical element by a distance, which may include a cavity filled with a material (such as air or a nanovoided material).

Abstract: In various embodiments, a pancake lens block (e.g., a reverse order crossed pancake lens block) including azimuthal compensation may include an optical element configured to transmit at least a portion of light emitted by an electronic display. The pancake lens block may further include an azimuthal compensator coupled to a surface of the optical element. Moreover, the azimuthal compensator may include a uniaxial birefringent material, and the azimuthal compensator may be configured to reduce an optical effect of stress birefringence in the optical element.

Abstract: In various embodiments, a reverse-order crossed pancake lens block having an index gradient structure may include an optical element configured to transmit at least a portion of radiation from a radiation source. Moreover, the pancake lens block may include an index-gradient structure that is spaced at a distance from the optical element, the distance configured to provide an optical path length in the pancake lens block. The index-gradient structure may be configured to provide an anti-reflective property to at least one surface of the optical element.

Abstract: In various embodiments, a pancake lens block may include (i) a first compound retarder comprising a first plurality of retarders oriented to a plurality of first axes of orientation, respectively, where the first compound retarder is configured to selectively transmit a portion of the emitted light, (ii) a partial reflector that receives the portion of emitted light from the first compound retarder and transmits the portion of the emitted light, (iii) a second compound retarder comprising a second plurality of retarders oriented to a plurality of second axes of orientation that are substantially orthogonal to the respective plurality of first axes of orientation, and (iv) a reflective polarizer configured to reflect the portion of the emitted light selectively transmitted by the second compound retarder back to the second compound retarder.