Reverse-order crossed pancake lens with a shaped polarizer

A head mounted display (HMD) comprising:

• an electronic display configured to emit light;
• and
• a pancake lens block comprising:
• an optical element configured to transmit at least a portion of the light emitted by the electronic display;
• and
• a shaped reflective polarizer spaced at a distance from the optical element;
• wherein the shaped reflective polarizer is configured to provide achromatic optical power to the pancake lens block.

A method of assembling a pancake lens block, the method comprising:

• configurating an optical element to transmit at least a portion of radiation from a radiation source;
• and
• spacing a shaped reflective polarizer from the optical element by a distance;
• wherein the shaped reflective polarizer is configured to provide achromatic optical power to the pancake lens block.