Open AccessEnhancement of the depth-of-field of integral imaging microscope by using switchable bifocal liquid-crystalline polymer micro lens array
Author(s) -
KiChul Kwon,
Munkh-Uchral Erdenebat,
Young-Tae Lim,
K. Joo,
Minkyu Park,
Hee-Won Park,
Jong-Rae Jeong,
HakRin Kim,
Nam Kim
Publication year - 2017
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.25.030503
Subject(s) - optics , materials science , focal length , polarization (electrochemistry) , lens (geology) , microscope , depth of field , integral imaging , microlens , liquid crystal , microscopy , optical microscope , cardinal point , optoelectronics , scanning electron microscope , physics , computer science , image (mathematics) , chemistry , artificial intelligence
An integral imaging microscopy (IIM) system with improved depth-of-field (DoF) using a custom-designed bifocal polarization-dependent liquid-crystalline polymer micro lens array (LCP-MLA) is proposed. The implemented MLA has improved electro-optical properties such as a small focal ratio, high fill factor, low driving voltage, and fast switching speed, utilizing a well-aligned reactive mesogen on the imprinted reverse shape of the lens and a polarization switching layer. A bifocal MLA switches its focal length according to the polarization angle and acquires different DoF information of the specimen. After two elemental image arrays are captured, the depth-slices are reconstructed and combined to provide a widened DoF. The fabricated bifocal MLA consists of two identical polarization-dependent LCP-MLAs with 1.6 mm and f/16 focal ratio. Our experimental results confirmed that the proposed system improves the DoF of IIM without the need for mechanical manipulation.