Patent ID: 10139592

Abstract:
An ocular optical system includes a first lens element, a second lens element, and a third lens element from an eye-side to a display-side in order along an optical axis. The first lens element, the second lens element, and the third lens element each include an eye-side surface and a display-side surface. The first lens element has refracting power. The display-side surface of the second lens element has a convex portion in a vicinity of the optical axis. The third lens element has refracting power. The ocular optical system satisfies: T3/G23≤4.3; and G3D/T3≤3.51, where T3 is a thickness of the third lens element along the optical axis, G23 is an air gap from the second lens element to the third lens element along the optical axis, and G3D is a distance from the third lens element to the display screen along the optical axis.