Extended depth-of-focus 3D micro integral imaging display using a bifocal liquid crystal lens

Abstract

We present a three dimensional (3D) micro integral imaging display system with extended depth of focus by using a polarized bifocal liquid crystal lens. This lens and other optical components are combined as the relay optical element. The focal length of the relay optical element can be controlled to project an elemental image array in multiple positions with various lenslet image planes, by applying different voltages to the liquid crystal lens. The depth of focus of the proposed system can therefore be extended. The feasibility of our proposed system is experimentally demonstrated. In our experiments, the depth of focus of the display system is extended from 3.82 to 109.43 mm.

Multidimensional Optical Sensing and Imaging System (MOSIS): From Macroscales to Microscales

“…Micro integral imaging can be combined with optical see-through head-mounted display (OST-HMD) for an > REPLACE THIS LINE WITH YOUR PAPER IDENTIFICATION NUMBER (DOUBLE-CLICK HERE TO EDIT) < 20 augmented reality 3D display system [17] [35][36] [105]. Micro integral imaging creates a 3D image source for the head-mounted display (HMD) viewing optics.…”

“…In contrast, some other 3D sensing techniques, such as the time-of-flight camera [10] or structured light techniques [11][12], may not work well for long range objects. Integral imaging is a promising technique that has been used in various fields, such as 3D sensing [13], 3D displays [14][15] [16] [17], holographic display [18], 3D imaging of objects in turbid water [19], 3D tracking [20] and 3D target detection and recognition [21] [22], photon counting 3D sensing and visualization [23][24] [25], 3D microscopy [26][27] [28] [29][30] [31] and endoscopy for micro scale 3D imaging and display [32] [33], head tracking 3D display [34], 3D augmented reality [35][36] [37] [38], to cite a few.…”

10‐3: Design of a High‐performance Optical See‐through Light Field Head‐mounted Display

“…However, like other InI-based display technologies, the conventional micro-InI method demonstrated in [8,9] suffers from several major limitations due to the very nature of the integral imaging such as the low spatial resolution through a large depth volume and crosstalk between the elemental images. Several methods have been explored to address these issues in direct-view InI-based displays [10][11][12][13], however, it is difficult, if not impractical, to directly transfer such techniques to an InI-HMD due to their complexity and various differences between direct-view displays and HMDs. Recently, using off-the shelf optics, we demonstrated a new practical method for an InI-HMD using a tunable lens and an aperture array, which is capable of rendering a reconstructed 3D scene for a relatively large depth range without degrading the image quality as well as a reasonable viewing window without noticeable crosstalk [14].…”

An integral‐imaging‐based head‐mounted light field display using a tunable lens and aperture array

“…However, like other InI‐based display technologies, the simple micro‐InI‐based HMD architecture consisting of a microlens array (MLA) and a micro‐display suffers from several major limitations because of the very nature of the InI such as the low spatial resolution through a large depth volume and crosstalk between the elemental images. Several methods have been explored to address these issues, such as using a varifocal liquid lens array, or a bifocal liquid crystal lens to enhance the depth, and using movable pinhole array or a periodic black mask with a layer of high refractive index packing medium to enhance the viewing window and equivalently reduce the crosstalk. Although all of these approaches help to improve the performance of the traditional InI display system, it might be difficult, if not impractical, to directly transfer such techniques to an InI‐HMD because of their complexity and various differences between conventional displays and HMDs.…”