Extended depth-of-field projection method using a high-speed projector with a synchronized oscillating variable-focus lens

Appl Opt. 2021 May 1;60(13):3917-3924. doi: 10.1364/AO.419470.

Abstract

For a projector-based virtual reality (VR) or augmented reality (AR) display, a large depth of field and a high-speed image refresh rate are important keys to improve the projector's performance. Here, we propose a solution that extends the depth of field of the projection using a variable-focus lens and a high-speed projector as well as a control method that synchronizes oscillation of the variable-focus lens with the high-speed projector. The experiment confirms that the proposed system can project the well-focused and dynamically changeable contents on six different planes. Its projection range varies from 0.3 m to 1.5 m, and the refresh rate is 166.7 Hz.