Patent ID: 10324292

Abstract:
The present invention discloses a short-range optical amplification module, which includes a first phase delay plate, a transflective mirror, a second phase delay plate and a reflective polarizing plate that are arranged sequentially, wherein: the transflective mirror includes a first optical surface and a second optical surface; the first optical surface is adjacent to the second phase delay plate; the second optical surface is a transflective optical surface, and the second optical surface is adjacent to the first phase delay plate; the focal length fs2 of the reflection surface of the second optical surface meets the following condition: F≤fs2≤5F, wherein F is the system focal length of the short-range optical amplification module, and F meets the following condition: 10 mm≤F≤35 mm. By performing parameter refining on the fs2 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 virtual reality (VR) device, so that the VR device can realize a wide field angle, a large eyebox and a high-quality imaging effect, and hence a better user experience.