Patent ID: 11927782
Assignee: BEIJING RAYBOCH TECHNOLOGY CO., LTD.
Field: Optics (Instruments)
Classification: CPC G  H | IPC G  H

Claim 0:
1. A phase retardation device, comprising: a linear polarization layer, a first alignment layer, a first liquid crystal layer, and a second liquid crystal layer;
the linear polarization layer being located on a side of a light source and configured to convert a received light into a linear polarized light;
the first alignment layer being located on a side of the linear polarization layer away from the light source and configured to align liquid crystals in the first liquid crystal layer based on a preset alignment angle;
the first liquid crystal layer being located on a side of the first alignment layer away from the light source and configured to convert the linear polarized light to an elliptical polarized light;
the second liquid crystal layer being located on a side of the first liquid crystal layer away from the first alignment layer, the second liquid crystal layer comprising a first subpart, a second subpart and a third subpart, the first subpart being adjacent to the first liquid crystal layer, a liquid crystal alignment angle of the first subpart being the same as a liquid crystal alignment angle of the first liquid crystal layer, the second subpart being a helical structure having a preset helical angle, a liquid crystal alignment angle of the third subpart being determined based on the preset alignment angle and the preset helical angle, and the second liquid crystal layer being configured to convert the elliptical polarized light to a circular polarized light via the helical structure of the second subpart.