公开(公告)号：US20240310566A1

公开(公告)日：2024-09-19

申请号：US18597862

申请日：2024-03-06

申请人： Apple Inc.

发明人： Choon How Gan ,  Adam Backer ,  Ben-Li Sheu ,  Francesco Aieta ,  Ping Qu ,  Se Baek Oh ,  Zhenwen Ding

IPC分类号： F21V8/00 ,  G02B27/01

CPC分类号： G02B6/0016 ,  G02B6/0018 ,  G02B6/0036 ,  G02B27/0172

摘要： An electronic device may have a waveguide, an input coupler that couples light into the waveguide, and an optical coupler that couples the light out of the waveguide. A medium may be layered onto the waveguide. The input coupler may include a first surface relief grating (SRG) and the optical coupler may include a second SRG in the medium. The first SRG may be a non-binary staircase SRG having ridges with multiple steps. The second SRG may be a binary SRG having troughs that extend to the height of the lowest steps of the first SRG. A reflective layer may fill the first SRG. Forming the input coupler using a staircase SRG may serve to maximize the in-coupling efficiency of the input coupler, thereby maximizing the efficiency with which the light is provided to an eye box.