Biomedical bandpass filter for fluorescence microscopy imaging based on TiO2/SiO2 and TiO2/MgF2 dielectric multilayers

3rd International School and Conference on Optoelectronics, Photonics, Engineering and Nanostructures (Saint Petersburg OPEN 2016)

Butt, M.A.^1 ; Fomchenkov, S.A.^1,2 ; Ullah, A.^3 ; Verma, P.^1 ; Khonina, S.N.^1,2

Samara State Aerospace University, Moskovskoye Shosse 34, Samara

443086, Russia^1

Image Processing Systems Institute3, Russian Academy of Sciences, Molodogvardeyshaya 151, Samara

443001, Russia^2

Department of Electronic Engineering, Balochistan University of Information Technology, Engineering and Management Sciences (BUITEMS), Quetta, Pakistan^3

关键词: Dielectric multilayers;    Fluorescence microscopy imaging;    High refractive index;    Highly reflecting mirrors;    Low-refractive-index materials;    Multilayer dielectrics;    Titanium dioxides (TiO2);    Visible spectrometers;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/741/1/012136/pdf
DOI  :  10.1088/1742-6596/741/1/012136

来源: IOP

【 摘 要 】

We report a design for creating a multilayer dielectric optical filters based on TiO2and SiO2/MgF2alternating layers. We have selected Titanium dioxide (TiO2) for high refractive index (2.5), Silicon dioxide (SiO2) and Magnesium fluoride (MgF2) as a low refractive index layer (1.45 & 1.37) respectively. Miniaturized visible spectrometers are useful for quick and mobile characterization of biological samples. Such devices can be fabricated by using Fabry-Perot (FP) filters consisting of two highly reflecting mirrors with a central cavity in between. Distributed Bragg Reflectors (DBRs) consisting of alternating high and low refractive index material pairs are the most commonly used mirrors in FP filters, due to their high reflectivity. However, DBRs have high reflectivity for a selected range of wavelengths known as the stopband of the DBR. This range is usually much smaller than the sensitivity range of the spectrometer range. Therefore a bandpass filters are required to restrict wavelength outside the stopband of the FP DBRs. The proposed filter shows a high quality with average transmission of 97.4% within the passbands and the transmission outside the passband is around 4%. Special attention has been given to keep the thickness of the filters within the economic limits. It can be suggested that these filters are exceptional choice for florescence imaging and Endoscope narrow band imaging.