Crosstalk Reduction in Voxels for a See-Through Holographic Waveguide by Using Integral Imaging with Compensated Elemental Images
The representation of three-dimensional volumetric pixels, voxels, is an important issue for the near-to-eye displays (NEDs) to solve the vergence-accommodation conflict problem. Although the holographic waveguides using holographic optical element (HOE) couplers are promising technologies for NEDs...
Main Authors: | , , |
---|---|
Format: | Article |
Language: | English |
Published: |
MDPI AG
2021-06-01
|
Series: | Photonics |
Subjects: | |
Online Access: | https://www.mdpi.com/2304-6732/8/6/217 |
id |
doaj-75c7afb89c3a46a2886a132398265195 |
---|---|
record_format |
Article |
spelling |
doaj-75c7afb89c3a46a2886a1323982651952021-06-30T23:59:06ZengMDPI AGPhotonics2304-67322021-06-01821721710.3390/photonics8060217Crosstalk Reduction in Voxels for a See-Through Holographic Waveguide by Using Integral Imaging with Compensated Elemental ImagesJiwoon Yeom0Yeseul Son1Kwangsoon Choi2Korea Electronics Technology Institute, World Cup buk-ro 54-gil, Mapo-gu, Seoul 03924, KoreaKorea Electronics Technology Institute, World Cup buk-ro 54-gil, Mapo-gu, Seoul 03924, KoreaKorea Electronics Technology Institute, World Cup buk-ro 54-gil, Mapo-gu, Seoul 03924, KoreaThe representation of three-dimensional volumetric pixels, voxels, is an important issue for the near-to-eye displays (NEDs) to solve the vergence-accommodation conflict problem. Although the holographic waveguides using holographic optical element (HOE) couplers are promising technologies for NEDs with the ultra-thin structure and high transparency, most of them have presented only a single and fixed depth plane. In this paper, we analyze the imaging characteristics of holographic waveguides, particularly to represent the arbitrary voxels and investigate the voxel duplication problem arising from the non-collimated light from the voxels. In order to prevent the image crosstalk arising from the voxel duplication, we propose an adjustment method for the emission angle profile of voxels by using the integral imaging technique. In the proposed method, the sub-regions of elemental images, which correspond to the duplicated voxels, are masked in order to optimize the emission angle of integrated voxels. In the experimental verification, a see-through integral imaging system, based on the organic light-emitting diode display and a holographic waveguide with the thickness of 5 mm, was constructed. The fabricated HOE in the waveguide showed high diffraction efficiency of 72.8 %, 76.6%, and 72.5 % for 460 nm, 532 nm, and 640 nm lasers, respectively. By applying the masked elemental images, the proposed method resulted in a reduced crosstalk in the observed voxels by 2.35 times. The full-color experimental results of see-through holographic waveguide with integral imaging are provided, whereby the observed 3D images are presented clearly without the ghost images due to the voxel duplication problem.https://www.mdpi.com/2304-6732/8/6/217holographic waveguideintegral imagingsee-through displayaugmented realityautostereoscopy |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
Jiwoon Yeom Yeseul Son Kwangsoon Choi |
spellingShingle |
Jiwoon Yeom Yeseul Son Kwangsoon Choi Crosstalk Reduction in Voxels for a See-Through Holographic Waveguide by Using Integral Imaging with Compensated Elemental Images Photonics holographic waveguide integral imaging see-through display augmented reality autostereoscopy |
author_facet |
Jiwoon Yeom Yeseul Son Kwangsoon Choi |
author_sort |
Jiwoon Yeom |
title |
Crosstalk Reduction in Voxels for a See-Through Holographic Waveguide by Using Integral Imaging with Compensated Elemental Images |
title_short |
Crosstalk Reduction in Voxels for a See-Through Holographic Waveguide by Using Integral Imaging with Compensated Elemental Images |
title_full |
Crosstalk Reduction in Voxels for a See-Through Holographic Waveguide by Using Integral Imaging with Compensated Elemental Images |
title_fullStr |
Crosstalk Reduction in Voxels for a See-Through Holographic Waveguide by Using Integral Imaging with Compensated Elemental Images |
title_full_unstemmed |
Crosstalk Reduction in Voxels for a See-Through Holographic Waveguide by Using Integral Imaging with Compensated Elemental Images |
title_sort |
crosstalk reduction in voxels for a see-through holographic waveguide by using integral imaging with compensated elemental images |
publisher |
MDPI AG |
series |
Photonics |
issn |
2304-6732 |
publishDate |
2021-06-01 |
description |
The representation of three-dimensional volumetric pixels, voxels, is an important issue for the near-to-eye displays (NEDs) to solve the vergence-accommodation conflict problem. Although the holographic waveguides using holographic optical element (HOE) couplers are promising technologies for NEDs with the ultra-thin structure and high transparency, most of them have presented only a single and fixed depth plane. In this paper, we analyze the imaging characteristics of holographic waveguides, particularly to represent the arbitrary voxels and investigate the voxel duplication problem arising from the non-collimated light from the voxels. In order to prevent the image crosstalk arising from the voxel duplication, we propose an adjustment method for the emission angle profile of voxels by using the integral imaging technique. In the proposed method, the sub-regions of elemental images, which correspond to the duplicated voxels, are masked in order to optimize the emission angle of integrated voxels. In the experimental verification, a see-through integral imaging system, based on the organic light-emitting diode display and a holographic waveguide with the thickness of 5 mm, was constructed. The fabricated HOE in the waveguide showed high diffraction efficiency of 72.8 %, 76.6%, and 72.5 % for 460 nm, 532 nm, and 640 nm lasers, respectively. By applying the masked elemental images, the proposed method resulted in a reduced crosstalk in the observed voxels by 2.35 times. The full-color experimental results of see-through holographic waveguide with integral imaging are provided, whereby the observed 3D images are presented clearly without the ghost images due to the voxel duplication problem. |
topic |
holographic waveguide integral imaging see-through display augmented reality autostereoscopy |
url |
https://www.mdpi.com/2304-6732/8/6/217 |
work_keys_str_mv |
AT jiwoonyeom crosstalkreductioninvoxelsforaseethroughholographicwaveguidebyusingintegralimagingwithcompensatedelementalimages AT yeseulson crosstalkreductioninvoxelsforaseethroughholographicwaveguidebyusingintegralimagingwithcompensatedelementalimages AT kwangsoonchoi crosstalkreductioninvoxelsforaseethroughholographicwaveguidebyusingintegralimagingwithcompensatedelementalimages |
_version_ |
1721349976201625600 |