Patent ID: 11940653
Assignee: JIAXING UPHOTON OPTOELECTRONICS TECHNOLOGY CO., LTD.
Field: Optics (Instruments)
Classification: CPC G | IPC F  G

Claim 0:
1. A diffraction optical waveguide, comprising a waveguide substrate and a grating structure formed on the waveguide substrate, wherein,
the grating structure comprises a plurality of optical unit structures arranged in an array along a plane, wherein each optical unit structure is a concave hole structure or a convex structure formed on the waveguide substrate and has a first end and a second end in a first direction parallel to the plane, and a distance between the first end and the second end along the first direction is a length L of each optical unit structure;
each optical unit structure has a maximum width W perpendicular to the first direction in a predetermined section along the first direction, where 0.3L≤W≤0.7L;
in the first direction, a central position of the predetermined section is at a predetermined distance d from the first end, where d<0.5L, and a width of each optical unit structure in a direction perpendicular to the first direction gradually decreases from the predetermined section to the first end as well as from the predetermined section to the second end, so that a centroid of a cross-section of each optical unit structure parallel to the plane is closer to the first end relative to the second end;
the grating structure is configured as a coupling-out grating, the coupling-out grating couples at least a part of the light propagating thereinto along a coupling-in direction within the waveguide substrate, out of the waveguide substrate by diffraction, and the coupling-in direction is substantially parallel to the first direction; and
the first end of each optical unit structure is located upstream along the coupling-in direction, and the second end is located downstream along the coupling-in direction.