Ocular optical system

• Main Authors: CHEN, WANUN, HUANG, CHUN-YANG
• Format: Patent
• Language: Chinese; English
• Published: 16.04.2019
• Subjects: OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICS; PHYSICS

An ocular optical system configured to allow imaging rays from a display image to enter an observer's eye through the ocular optical system so as to form an image is provided. A direction toward the eye is an eye side, and a direction toward the display image is a display side. The ocular optical system includes a lens element having an eye-side surface and a display-side surface. The lens element has an optical axis extending from the display side toward the eye side. The display-side surface of the lens element has a Fresnel lens design. The display-side has a plurality of effective sub-surfaces and a plurality of ineffective sub-surfaces. The effective sub-surfaces are configured to form an image of the image rays. Each ineffective sub-surface connects two adjacent effective sub-surfaces. The ocular optical system satisfies: 1.500 ≤ R1/SagI ≤ 4.000, where SagI is a sum of lengths of orthogonal projections of the effective sub-surfaces respectively onto the optical axis, and R1 is half of a clear aperture o