Laser inscription of pseudorandom structures for microphotonic diffuser applications
Author(s)
Alqurashi, Tawfiq
Alhosani, Abdulla
Dauleh, Mahmoud
Yetisen, Ali K
Butt, Haider
Type
Journal Article
Abstract
Optical diffusers provide a solution for a variety of applications requiring a Gaussian intensity distribution including imaging systems, biomedical optics, and aerospace. Advances in laser ablation processes have allowed the rapid production of efficient optical diffusers. Here, we demonstrate a novel technique to fabricate high-quality glass optical diffusers with cost-efficiency using a continuous CO2 laser. Surface relief pseudorandom microstructures were patterned on both sides of the glass substrates. A numerical simulation of the temperature distribution showed that the CO2 laser drills a 137 μm hole in the glass for every 2 ms of processing time. FFT simulation was utilized to design predictable optical diffusers. The pseudorandom microstructures were characterized by optical microscopy, Raman spectroscopy, and angle-resolved spectroscopy to assess their chemical properties, optical scattering, transmittance, and polarization response. Increasing laser exposure and the number of diffusing surfaces enhanced the diffusion and homogenized the incident light. The recorded speckle pattern showed high contrast with sharp bright spot free diffusion in the far field view range (250 mm). A model of glass surface peeling was also developed to prevent its occurrence during the fabrication process. The demonstrated method provides an economical approach in fabricating optical glass diffusers in a controlled and predictable manner. The produced optical diffusers have application in fibre optics, LED systems, and spotlights.
Date Issued
2018-04-21
Date Acceptance
2018-03-10
Citation
Nanoscale, 2018, 10 (15), pp.7095-7107
ISSN
2040-3364
Publisher
Royal Society of Chemistry
Start Page
7095
End Page
7107
Journal / Book Title
Nanoscale
Volume
10
Issue
15
Copyright Statement
© The Royal Society of Chemistry 2018. This article is licensed under a Creative Commons Attribution 3.0 Unported Licence.
License URL
Identifier
http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000430537200038&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=1ba7043ffcc86c417c072aa74d649202
Subjects
Science & Technology
Physical Sciences
Technology
Chemistry, Multidisciplinary
Nanoscience & Nanotechnology
Materials Science, Multidisciplinary
Physics, Applied
Chemistry
Science & Technology - Other Topics
Materials Science
Physics
COMPUTER-GENERATED HOLOGRAMS
OPTICAL DIFFUSERS
MICROLENS ARRAY
SURFACE-RELIEF
REAL-TIME
FABRICATION
SCATTERING
ABLATION
GLASSES
THIN
Publication Status
Published
Date Publish Online
2018-03-14