Refractive index

• A middle cylinder that surrounds the inner part of the cable (Cladding). This is one of the layers of materials that have a lower refractive index. By being in contact with the core which has a higher refractive index, the cladding causes light to be confined to the core of the fiber by total internal reflection. This is what will prevent any sort of leaks or loss of transmission data. • The outer protective layer, it is known as the jacket, buffer coating or polyurethane (PVC). The function of fiber optic cables can be explained through the physics of it. When light is transmitted through the Core of the fiber optic, light travels and constantly bounces off from the cladding of the fiber optic. This process is called total internal reflection, this is because the cladding does not absorb the actual light that is traveling through the core, and instead it bounces the light as explain before. This allows the light wave to travel great distances compared to the standard copper wires that are used. Loss of data transmittion in fiber optics is largly due to diffraction, when the light passes through the core, narrow slits or openings within its interior cause fringes of light and huge loss of package data as the light is bent. Another issue that can be seen is called return loss, a loss that takes place at the interruption of refractive index, expecially at an air-glass interface. At these interfaces, a fraction of the optical signal is reflected back towards the source,…

Introduction In general an optical sensor basically is like any other device which could converts light rays(laser beams) into electronic signals, into a form ie readable. Fiber optic sensors have numerous advantages over other conventional electronic sensors. Some important advantages are as below • Ability to integrate different structure. • Their inability to conduct electric current. • Highly resistive to electromagnetic interference. • Lightweight with high sensitivity. • Multiplexing…

air) into another medium (eg. glass) of a different optical density. When this happens, the ray of light changes speed causing it to bend either towards or away from the normal which is an imaginary line at 90 to the interface between two mediums. This is called refraction. How much it bends depends on the refractive indices of the two mediums which is a ratio of the speed of light in one medium compared with the second. For example the refractive index (n) of crown glass can be calculated as…

title>INTRODUCTION Optical constants (complex refractive index n, complex dielectric function ϵ, and reflection and absorption coefficients R and α) of materials are of great importance for optical metrology in the semiconductor industry.1,2 A high-performance complementary-metal-oxide-semiconductor process flow with 11 layers of metal requires about 75 photolayers and may contain up to 100 thickness measurements, most of them performed using spectroscopic ellipsometry.3 This technique has…

optical and optoelectronic applications due to their superior properties over conventional inorganic materials. For example, devices made out of organic polymers can be flexible, have better mechanical stability on impact, light weight and significantly effective in the cost of manufacturing. Due to these alluring properties, organic polymers are becoming extremely important in applications such as transparent/flexible optoelectronics, photovoltaics, field-effect transistors, sensors, lasers and…

samples for investigation which is expensive, time consuming and invasive. High sensitivity, minimum weight and large bandwidth makes fiber optic sensors the optimum photonic devise in radiative environment like nuclear power plants, where there is a need of evaluation and detection of radiation level and temperature change. The fiber optic sensor are application specific and are based on chemical and physical phenomenon which are then combined with electronic signals through more custom…

is a great alternative to glasses and contact lenses. The three main types of Laser Vision Correction are LASIK, PRK and LASEK (Thompson, 2016). The Laser Vision Correction procedure corrects the vision by reshaping the cornea in front of the eye in order to increase the focusing capacity and correct the refractive errors (Flaum, 2002). The LASIK eye surgery is considered to be the current most popular refractive surgery of all (Thompson, 2016). Approximately 99% of the patients are satisfied…

The study design of the Evans study was based upon the use of both direct interview and observational study methods. For the direct interview methods, social demographic data, medical variables, employment status, and subjective indicators were obtained via personal interview Interviewers were trained during a three-day training session to ensure uniform interview processes. Completed interviews were obtained from 90% of eligible patients (Evans et al, 1985). The responses to these interview…

(2005) developed walkability index (WI) to measure the characteristics of the physical environment that contribute to walkable neighbourhood design. Leslie et al. (2007) adapted the WI to Australia. WI for these studies contains four main data components. The first component is residential density which is the number of residential units per particular areal unit within a neighbourhood. A high residential density value shows that more people live in the area. The second data component of the…

“Topography-guided laser refractive surgery” by Holland et.al explains these in more detail. This article can be found in the Current Opinion in Ophthalmology Journal, and it clears up questions about the differences between wavefront and topography-guided surgeries. The article starts by touching on the current legal status of these treatments in different countries and follows this by explaining the differences between wavefront and topography-guided measurements and what each is effective at…