Patent ID: 11885997
Assignee: RICOH COMPANY, LTD.
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC G | IPC F  G

Claim 0:
1. A light-guide member, comprising:
an incidence portion to receive an image light;
an exit portion to emit the image light to an outside of the light-guide member; and
an extraction portion configured to guide the image light to the exit portion and extract the image light, wherein
the extraction portion includes a plurality of three-plane structures,
each three-plane structure includes an inclined plane, a first plane and a second plane sequentially arranged in order from a reflective portion,
within each three-plane structure, the first plane is placed on a first end of the second plane, the first end being closer to the incidence portion than a second end of the second plane,
the first plane, the second plane and the inclined plane of each three-plane structure are alternately arranged to form a stepwise shape that descends towards the exit portion,
in each three-plane structure, the second plane is closer to the exit portion than the inclined plane and the first plane are to the exit portion, and
the second plane of each three-plane structure is parallel to the exit portion.