Patent ID: 11874488
Assignee: JIAXING UPHOTON OPTOELECTRONICS TECHNOLOGY CO., LTD.
Field: Optics (Instruments)
Classification: CPC G | IPC F  G

Claim 15:
16. The diffractive optical waveguide of claim 1, wherein the coupling-out grating further comprises a second grating, and the second grating comprises a plurality of second optical unit structures arranged in an array along the plane and has the first grating vector, the second grating vector, and the third grating vector;
the second optical unit structure has a second predetermined profile when viewed in the plane, and the second predetermined profile has a seventh vertex, an eighth vertex, a ninth vertex and a tenth vertex, arranged in sequence along the circumferential direction, wherein the seventh vertex and the eighth vertex are located at one end of the second predetermined profile in the first direction, the ninth vertex and the tenth vertex are located at the other end of the second predetermined profile in the first direction, the seventh vertex and the ninth vertex are outermost vertices of the second predetermined profile in the second direction;
a fifth straight line extending through the seventh vertex and the eighth vertex and a sixth straight line extending through the ninth vertex and the tenth vertex are substantially perpendicular to the first direction, and a seventh straight line extending through the seventh vertex and the tenth vertex forms a third angle θ3 with the first direction, an eighth straight line extending through the eighth vertex and the ninth vertex forms a fourth angle θ4 with the first direction, where 15°≤|θ3|≤45°, 15°≤|θ4|≤45°, and the third angle θ3 and the included angle θ4 have the same positive sign or the same negative sign; and
the first grating and the second grating are arranged side by side in the second direction, so that the third straight line and the fourth straight line in the first predetermined profile of the first grating tilt towards the second grating along the first direction, and the seventh straight line and the eighth straight line in the second predetermined profile of the second grating tilt towards the first grating along the first direction.