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Principles of Polymer Optical Fibers
Published in Marcelo Martins Werneck, Regina Célia da Silva Barros Allil, Plastic Optical Fiber Sensors, 2019
Ricardo Oliveira, Lúcia Bilro, Rogério N. Nogueira
Stacking is the main method used for the production of silica photonic crystal fibers (PCFs) (see Figure 2.16a), being also employed for the fabrication of mPOFs based on PS (Shin & Park, 2004), PF (Nagasawa, Kondo, Ishigure, & Koike, 2005), and PMMA (van Eijkelenborg et al., 2008). In this method, tiny capillary tubes are piled up with the predefined arrangement and then filled into a hollow core tube in order to form the preform that later will be heat drawn to fiber. One obvious limitation of this procedure is the limited hole arrangement. Additionally, the process can be time consuming, prone to human errors, and expensive, since it is a discontinuous process and requires pilling up of thousands of capillary tubes to form a preform.
Guiding Lightwaves
Published in Araz Yacoubian, Optics Essentials, 2018
Optical fibers come in various formats. For long-distance communication, a common fiber is a single-mode fiber, where only one mode of light is trapped. The core and cladding layers are approximately 9 microns and 125 microns in diameter, respectively. Typically these fibers have very low loss for telecommunication wavelengths of 1.3 microns and 1.55 microns. For short distance communication, and for other applications, such as for sensing and for lighting, multimode fibers are also used. Examples of multimode fibers are 65 micron and 900 micron core fibers. A relatively new class of fibers called photonic crystal fibers achieve light trapping by incorporating small periodically structured holes that run parallel inside the fiber, instead of using core-cladding structures.
High Manufacturing Technology
Published in Abdul Al-Azzawi, Advanced Manufacturing for Optical Fibers and Integrated Photonic Devices, 2017
Figure 5.14 illustrates the stack-and-draw process, the most widely used method for fabricating photonic crystal fiber. Silica capillary tubes are stacked by hand to make a preform. The preform has a diameter of 20 to 40 mm. The core is embedded by omitting several capillaries from the center of the stack. Typically, several hundred capillaries are stacked in a close-packed array and inserted into a jacketing tube to create a fiber preform. This preform is drawn into fiber in two stages, adding a second jacketing tube before the final draw. The extra jacket enables the creation of fibers with a standard outer diameter, while providing independent control over the photonic bandgap pitch, and hence the operating wavelength. The preform is drawn into fiber, as shown in Figure 23.8. The preform is attached to a precision feed that moves it into the furnace at a proper speed to soften the silica to a diameter of 2 to 4 mm. The drawing fiber passes through high-precision diameter control and is monitored by imaging or x-ray to detect any nonhomogeneity or bubbles in the drawing fiber. It is then inserted into a silica sleeve tube and drawn down again to a fiber of typically 125 μm in diameter. After this stage, the diameter is continuously monitored by an accurate measurement and monitoring device. The fiber is then covered by a colored jacket layer. Again, the jacket layer undergoes diameter control and monitoring. The end of the fiber cable is attached to a rotating spool, which turns steadily. The fiber cable is then tested for attenuation in dB per kilometer, for dispersion, and any other requirements specified by the customer. Drawn photonic crystal fiber lengths of a few kilometers are typical.
Design of an asymmetric gold-coated photonic crystal fiber (PCF) polarization filter based on surface plasmon resonance (SPR)
Published in Instrumentation Science & Technology, 2021
Dan Yang, Zhulin Wei, Bin Xu, Tonglei Cheng
Photonic crystal fiber (PCF) is a fiber that periodically arranges low refractive index materials in the background of high refractive index. In PCF, the background material is usually silicon dioxide, and the low refractive index region is usually composed of pores extending along the whole fiber length.[1] Compared with conventional optical fibers, PCF possesses unique properties such as single-mode transmission, flat dispersion, controllable nonlinearity, adjustable birefringence, and controlled effective mode area, among others.[2] PCF may also be used in as a distinct optical material because different materials can fill the air holes, such as liquids, gases, and even solids.[3] These excellent characteristics make PCF widely used in temperature sensing,[4] biosensing sensing,[5] filter[6] and other fields. Additionally, the transmission properties and optical interaction of PCF may be improved and modified through selectively filling the cladding air holes with metals, liquid crystals or polymer in photonics.[7]
Simultaneous measurement of refractive index and temperature based on a long period fiber grating inscribed in a photonic crystal fiber with an electric-arc discharge
Published in Instrumentation Science & Technology, 2019
Chao Du, Qi Wang, Sheng Hu, Yong Zhao
The photonic crystal fiber has unique properties which are different from the conventional single mode fiber, especially because its structure is flexible according to the measurement requirements, and these advantages have demonstrated potential as various fiber sensors. The air holes in cladding provide a new platform for internal refractive index measurement, and a higher refractive index sensitivity can be realized in photonic crystal fiber long period grating due to the direct interactions between light and the analytes.[15] Compared with the long period fiber grating based conventional single mode fiber,[16] the long period fiber grating inscribed in photonic crystal fiber shows higher external refractive index sensitivity,[17,18] but its temperature sensitivity is less than 10 pm/°C because of the thermal properties of pure silica. In order to reduce the limitations of cross-sensitivity, a cascaded sensing element with a relative higher temperature sensitivity should be adopted for temperature compensation.
Three Ways Chip to Chip Communication via a Single Photonic Structure: A Future Paragon of 3D Photonics to Optical VLSI
Published in IETE Journal of Research, 2023
S. Boobalan, P. Venkatesh Kumar, K. Vinoth Kumar, G. Palai
A set of electronic circuits is placed on one flat piece of semiconductor material is known as integrated circuit. Basically silicon is chosen as the semiconductor materials where flat piece is called chip. Further the combination of large number of tiny transistors into a small chip leads to the smaller, cheaper and faster as compared to the discrete electronic elements. The device which has ample electronic circuits in a single chip is called nano-electronics. Even though researchers from electronic community focuses on the nano-electronic devices at the present time, it has certain limitations pertaining to the excess heat generation as well as scattering effect due to the interaction of electrons with lattices. To keep away these limitations, photonic technology stands with nano-material nowadays. Even though, research on photonics is around 30 years around (staring from 1990 to 2020) the globe, many type of photonic-based devices have been explored both theoretically as well as experimentally during three decades [1,2]. For example, the devices with respect to the one dimensional photonic crystal structure have entered to the market in their physical form. Apart from this an extensive research has also been carried out using both 2D and 3D photonic structures. However, the most successful application of photonic crystal is based on 2D photonic structure; for example, photonic crystal fiber. Beside this, recently a few works have found in the literatures [3–7]. For example; reference [3] and [4,5] deal with the sensing application where measurement of glycerol and haemoglobin in human blood is computed. Similarly, reference [6–9] discusses different application with respect to communication where solar cell, optical lock and optical demux, etc. have been found. Though the above said application deals with the different applications relating to the communication; the present work discusses a different application where three ways chip to chip communication is seen using a single photonic structure. Moreover recently a paper [9] relating to one way chip to chip communication is disclosed in the literature, where one dimensional photonic structure has been deployed. The present paper is organised as follows; section 2 deals with the operational mechanism of the work along with the structure where section 3 deals with the result and analysis to realise chip to chip communication. Finally, conclusions are indicated in the section 4.