Patent ID: 11947127
Assignee: ENVISICS LTD
Field: Optics (Instruments)
Classification: CPC G  B | IPC B  G

Claim 16:
17. A method of providing a head-up display for a vehicle having a window, the method comprising:
providing a plurality of pictures, each picture comprising a first picture component and a second picture component;
projecting the pictures onto the window of the vehicle in order to form a first virtual image of the first picture component at a first virtual image distance from a viewing plane and a second virtual image of the second picture component at a second virtual image distance from the viewing plane, wherein the first virtual image distance is substantially different from the second virtual image distance, and wherein light of the first picture component is polarised in a first polarisation direction and light of the second picture component is polarised in a second polarisation direction perpendicular to the first polarisation direction,
wherein the projection comprises
receiving light of the first picture component and light of the second picture component at a first polarisation-selective reflective surface having a first optical power;
reflecting light of the first picture component from the first polarisation-selective reflective surface and transmitting light of the second picture component through the first polarisation-selective reflective surface;
receiving from the first polarization-selective reflective surface light of the second picture component at a second reflective surface having a second optical power,
the first optical power being different than the second optical power.