Light control device

A method of head-up display in a vehicle, the method comprising:

• displaying a hologram of an image on a spatial light modulator;
• illuminating the hologram displayed on the spatial light modulator to form spatially modulated light encoded with the hologram;
• propagating the spatially modulated light to a scattering diffuser disposed at an image reconstruction plane of the hologram such that an image reconstruction of the image is output by the diffuser;
• coupling the output of the scattering diffuser into an input port of a waveguide pupil expansion system comprising a planar waveguide pupil expander;
• replicating the image in a first direction and second direction to form an array of replicas of the image;
• transmitting the array of replicas of the image through a plurality of tilted channels in a lattice structure of a reflection suppression device, wherein the lattice structure comprises a plurality of lattice elements extending from the surface of the planar waveguide pupil expander, at least one lattice element having a first pair of opposing parallel first sides and a second pair of opposing parallel second sides, the first sides being longer than the second sides;
• relaying the plurality of replicas of the image to an eye-box of the head-up display using the windscreen of the vehicle and/or a diffractive light-turning component;
• and
• simultaneously with the transmitting, blocking sunlight on an optical path to the eye-box via the waveguide pupil expander using walls of the tilted channels and/or blocking zeroth-order light from the diffractive light-turning component using walls of the tilted channels.