Patent ID: 11940759
Assignee: ENVISICS LTD
Field: Optics (Instruments)
Classification: CPC G | IPC G

Claim 13:
14. A method of operating a projector arranged to project an image comprising a light feature within a display area on a display plane, wherein the light feature comprises a dark region surrounded by a light region, the method comprising:
providing a light sensor spatially separated from the display plane;
projecting the image within the display area on the display plane, wherein light of the light feature is at least partially disposed around the light sensor, without substantially impinging thereon, when operated in an aligned state, wherein the display area is correctly positioned with a selected alignment on the display plane in the aligned state, and wherein, when operated in the aligned state, a reference point in the dark region of the light feature is coincident with a reference point of the light sensor;
detecting, by the light sensor, light of the light feature during a light sensing interval, and
determining a misaligned state when the detected light is greater than a threshold, wherein the display area is not correctly positioned in the display plane in the misaligned state.