Projection-type see-through holographic three-dimensional display

Koki Wakunami,Ryutaro Oi,Kenji Yamamoto,Po-Yuan Hsieh,Yasuyuki Ichihashi,Yi-Pai Huang,Hisayuki Sasaki,Makoto Okui,Takanori Senoh

doi:10.1038/ncomms12954

Abstract

Owing to the limited spatio-temporal resolution of display devices, dynamic holographic three-dimensional displays suffer from a critical trade-off between the display size and the visual angle. Here we show a projection-type holographic three-dimensional display, in which a digitally designed holographic optical element and a digital holographic projection technique are combined to increase both factors at the same time. In the experiment, the enlarged holographic image, which is twice as large as the original display device, projected on the screen of the digitally designed holographic optical element was concentrated at the target observation area so as to increase the visual angle, which is six times as large as that for a general holographic display. Because the display size and the visual angle can be designed independently, the proposed system will accelerate the adoption of holographic three-dimensional displays in industrial applications, such as digital signage, in-car head-up displays, smart-glasses and head-mounted displays.

Highlights

Owing to the limited spatio-temporal resolution of display devices, dynamic holographic three-dimensional displays suffer from a critical trade-off between the display size and the visual angle
Under the condition that a plane wave illuminates the hologram displayed on an spatial light modulators (SLMs), the minimum distance, ZMIN, at which the entire display area can be viewed is given by ZMIN 1⁄4 W/(2tan(yDIF/2)), with visual angle yVIS identical to the above maximum diffraction angle yDIF (Fig. 1a)
Our display system, namely, holographic projection with a designed HOE (DDHOE) as a holographic screen, is one of the improved solutions to overcome the restriction of the pixel resolution of current display devices even though the observable area will be limited

Summary

Introduction

Owing to the limited spatio-temporal resolution of display devices, dynamic holographic three-dimensional displays suffer from a critical trade-off between the display size and the visual angle. The enlarged holographic image, which is twice as large as the original display device, projected on the screen of the digitally designed holographic optical element was concentrated at the target observation area so as to increase the visual angle, which is six times as large as that for a general holographic display. One approach to overcoming this problem so as to increase both the display size and the visual angle at the same time is to concentrate the reconstructed light at a target observation area by using a convex lens[11] or a custom-designed mirror[12]. Komar pointed out several problems, namely, the difficulty of fabricating a large holographic screen, the severe image distortions of 3D space owing to the mismatch between the axial and lateral dimensions caused by the enlarged projection, and the image distortion due to observation of the hologram screen from an oblique direction

Methods

Results

Conclusion