Patent ID: 10185148

Abstract:
The present invention discloses a short-range optical amplification module, which includes, sequentially from the image side to the object side, a reflective polarizing plate, a first phase delay plate, a third lens and a second phase delay plate, wherein the short-range optical amplification module further includes a first lens and/or a second lens that are/is located on either side of any one of the reflective polarizing plate, the first phase delay plate, the third lens and the second phase delay plate. In the third lens, the optical surface adjacent to the second phase delay plate is a transflective optical surface; the reflection surface-containing focal length f3 of the third lens meets the following condition: 1F≤f3≤2F, wherein F is the focal length of the short-range optical amplification module. By performing parameter refining on the f3 that influences the optical amplification effect, the module can keep a small overall thickness while obtaining a large optical amplification effect and it can be applied in a small-size VR device, so that the VR device can realize a wide field angle, a large eyebox and high-quality imaging effect, and hence a better user experience.