scholarly journals Determining the refractive index, absolute thickness and local slope of a thin transparent film using multi-wavelength and multi-incident-angle interference

2020 ◽  
Vol 28 (16) ◽  
pp. 24198 ◽  
Author(s):  
Mengfei He ◽  
Sidney R. Nagel
2001 ◽  
Vol 665 ◽  
Author(s):  
Song Yun Cho ◽  
Eunkyoung Kim

ABSTRACTEffect of photo-irradiation on the color change of diarylethene polymer films was investigated. Diarylethene polymer films were prepared from photopolymerization of a radical curable mixture of diarylethene compound and a fluoroalkylacrylate containing a photo initiator. 1-[6'-(Methacryloxyethyloxycarbonyl)-2'-methylbenzo[b]thiophene-3'-yl]-2- (2"-methylbenzo[b]thiophene-3"-yl)hexafluorocyclopentene (MMBTF6) was synthesized from 2,3-bis(2-methylbenzo[b]thiophene-3-yl)hexafluorocyclopentene (BTF6) in three steps. 2,2,3,3-Tetrafluoro-1,4-butyldiacrylate (TFBDA) was synthesized from the corresponding diol and acryloyl chloride in the presence of a base. The photocurable mixture was coated on a substrate and subjected to antinic irradiation, to afforded homogeneous transparent film. A mask image was recovered on the film by a light of 365 nm and read by a visible light (λ > 700 nm) without destruction of the image. To erase the recorded image, a white light or a visible light was irradiated. Photochromic quantum yield and photo-induced refractive index change of the diarylethene bound polymer film were determined as 0.12 and 0.0006 respectively.


2019 ◽  
Vol 0 (0) ◽  
Author(s):  
Haythem Bany Salameh ◽  
Hazem Khrais

AbstractIn this paper, we develop a novel demultiplexer design for Coarse Wavelength Division Multiplexer (CWDM). The device consists of multi-layer inhomogeneous semi-conductor material, where the refractive index of each layer is graded according to a predefined profile. The proposed design exploits the ray’s spatial shift that results from the material dispersion as different wavelengths propagate through the different layers of the device. Our design forces the multiplexed light to refract after propagation for short distance within the device leading to smaller device size while providing the needed spatial shift between the ray’s of the adjacent multiplexed wavelengths. The proposed structure can be easily implemented using the well-established technology utilized in fabricating existing graded-index fibers. The impacts of the various design parameters (such as the incident angle, number of layers, the layer thickness, the spacing between adjacent wavelengths, the refractive index difference) on the amount of achieved spatial shift between the adjacent wavelengths and the size of the device are investigated. Compared to previous proposed techniques, our device can be easily fabricated to provide higher spatial shift while reducing the device size with by controlling the different design parameters.


2015 ◽  
Vol 1105 ◽  
pp. 136-140
Author(s):  
Shinn Fwu Wang ◽  
Fu Hsi Kao ◽  
An Li Liu

In this paper, a new-type electro-optical sensor based on the total-internal reflections theory in heterodyne interferometry is proposed. The sensor is designed as a semi-circle shape. It is made of BK7 glass with the refractive index of 1.51509. And the end surface of the sensor is designed as a micro-mirror. The phase difference between s-and p-polarizations at the output of the optical fiber sensor can be obtained when a heterodyne optical source is launched into the electro-optical sensor at a suitable incident angle. By numerical calculation, the resolution of the system by using the intensity method can reach refractive index unit (RIU) in the measurement range of. The electro-optical sensor could be valuable for chemical, biological and biochemical sensing. It is with some advantages, such as, high resolution and stability, high sensitivity and real-time measurement.


2006 ◽  
Vol 39 (5) ◽  
pp. 749-751 ◽  
Author(s):  
Byeongdu Lee ◽  
Chieh-Tsung Lo ◽  
Soenke Seifert ◽  
Randall E. Winans

Grazing-incidence small-angle X-ray scattering (GISAXS) patterns of a silver behenate composite film, which has a typical layered structure, are described. The peak position of the film in the GISAXS pattern was varied depending on the incident angle, which was well described by taking into account the refraction and the reflection effects. Since the refractive index of samples depends on sample preparation, it is recommended that the measurement of silver behenate as a standard be done in conventional transmission mode to avoid any complexity.


2014 ◽  
Author(s):  
Abhishek Wadhwa ◽  
Sung-Yong Park

We present optical analyses of a microfluidic tunable liquid prism to find its optimized configuration that can achieve wider beam steering as well as less reflection loss and eventually maximize solar energy capture without mechanical tracking. For this study, four different prism configurations are compared from single to quad-stacked ones with various refractive indices of the liquids filled in the prism. Its beam steering capability can be improved by increasing the refractive index ratio between the liquids used and by using higher number of the stacked prisms. The quad-stacked prism is able to steer incoming sunlight with an incident angle of a α ≤ ± 75° at an apex angle of φ ≤ ± 30°, which represents more than 5 times improvement, when it is compared to the single prism using the same liquids. For appropriate liquid material selection, the effect of refractive index ratio, r = n2/n1, on beam steering was additionally studied. However, one considerable issue is the fact that the better beam steering, the more reflection loss. This is because both higher number of interfaces and larger refractive index ratio make more reflection at each of the interfaces. Our reflectance analysis showed that the quad prism performs inferior to the double prism until α = ± 32°, while being of superior beam steering performance. To further reduce the solar energy loss through the quad prism, a modified configuration is proposed with a thin film added to the interfaces. 50 % of the total reflection was reduced. Our technology promises an alternative to a low-cost and high-efficiency solar tracking system capable of beam steering as wide as ± 75° and reflection loss as low as 4.5%, during all daily tracking of the sun.


RSC Advances ◽  
2016 ◽  
Vol 6 (75) ◽  
pp. 70825-70831 ◽  
Author(s):  
Mei Chen ◽  
Guoyan Zhang ◽  
Xiao Liang ◽  
Wanshu Zhang ◽  
Le Zhou ◽  
...  

A novel active silicone–oligomers used as chemical intermediates in optical applications were synthesized and one of their derivatives, a transparent film with high refractive index, were presented.


Sign in / Sign up

Export Citation Format

Share Document