Patent ID: 11874631
Assignee: ENVISICS LTD
Field: Optics (Instruments)
Classification: CPC G | IPC G

Claim 0:
1. A method of aligning a first holographic reconstruction and a second holographic reconstruction, the method comprising:
forming a first holographic reconstruction of a first plurality of discrete light features on a display plane using a first holographic projection channel, wherein the first holographic projection channel comprises a first spatial light modulator arranged to display holograms, the first spatial light modulator being arranged for illumination by light of a first wavelength;
forming a second holographic reconstruction of a second plurality of discrete light features on the display plane using a second holographic projection channel, wherein the second holographic projection channel comprises a second spatial light modulator arranged to display the holograms combined with at least one grating function, wherein each grating function has a respective displacement direction, the second spatial light modulator being arranged for illumination by light of a second wavelength;
capturing images of the display plane;
for each discrete light feature of the first plurality of discrete light features, individually determining a grating angle of each grating function required to align, in the respective displacement direction, the first holographic reconstruction of the respective discrete light feature of the first plurality of discrete light features with the second holographic reconstruction of the corresponding discrete light feature of the second plurality of discrete light features in order to obtain, for each displacement direction, a plurality of grating angles at a respective plurality of different locations on the display plane.