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Main presentation title goes here.
Main presentation title goes here.

... different wavelengths are placed either side of the cavity provide way of measuring coupling ...
Technical Article
Technical Article

... reference arm power is dispersed onto M photodetectors, the total reference power required to achieve shot noise-limited detection on all receivers simultaneously is more than that required for SS-OCT and TD-OCT by a factor of M. However, whether or not this requires re-design of the interferometer ...
Light Sources * II The Laser
Light Sources * II The Laser

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a 100-fold improvement in lithography resolution realized
a 100-fold improvement in lithography resolution realized

... understand how a waveguide operates. A waveguide is a physical structure capable of transmitting electromagnetic signals. As opposed to transmitting electromagnetic signals through the air, with a waveguide electromagnetic energy is confined between the guide’s walls. While conventional waveguides h ...
Observation of optical polarization Möbius strips
Observation of optical polarization Möbius strips

... We used a nanoprobe-based reconstruction technique to experimentally probe and reconstruct the electric field distributions generated in the focal plane, allowing the optical polarization Möbius strips hidden in this complex field structure to be observed (27). For this technique, we used a spherica ...
Living specimen tomography by digital holographic
Living specimen tomography by digital holographic

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Neutron Reflectivity
Neutron Reflectivity

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Introduction to Nonlinear Optics

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Measurement considerations when specifying

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secon harmonic generation

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Snell`s Law - Initial Set Up

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Lecture Series: Building the Future of Optical Modeling and Design
Lecture Series: Building the Future of Optical Modeling and Design

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... change to the thickness of the AR coatings. In principle the coatings need to be optimized for the non-orthogonal illumination angle. To first order the effect is geometrical (ie the light path is longer.) I have explored the impact by designing simple single and multiple layer coatings and found th ...
Brightfield contrast methods
Brightfield contrast methods

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Polarization spectra of excited-state-Mg(3p)--rare-gas
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Fiberoptic Sample Holder (FOSH): Characteristics and Uses APPLICATION NOTE 1056-201
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... the bundle to the rod, a slight difference in bundle and rod length, or the reflectivity of the light at each surface interface. They also do not include the effects of cooling on the parameters of the fiberoptic materials. If exact attenuation values are required, the user must determine them for h ...
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Varying the Effective Refractive Index to Measure

... confirmation of our theory which is built upon the concept of effective wave number in random media. This concept has never been examined so directly in strongly scattering media, simply because it was a very difficult parameter to access experimentally. Our experimental results not only match the t ...
Lec02 - nptel
Lec02 - nptel

... have a systematic behaviour with respect to time, i.e. if the electric field orients itself randomly as a function of time (which may happen in case of a light from a source with large value of ∆λ) the light is said to be randomly polarized. In this type of polarization either the amplitude or direc ...
PDF Link
PDF Link

Optical and Electron Microscopy
Optical and Electron Microscopy

... the physical sciences. The imaging capabilities of the instrument are complemented with easily obtainable diffraction patterns for structure studies and spectroscopic techniques for chemical analysis of the specimen. The scanning electron microscope (SEM) combines, at least partially, the ease of us ...
nonlinear optics in photonic structures - Dipartimento SBAI
nonlinear optics in photonic structures - Dipartimento SBAI

... If the influences are periodic in time, the response of a nonlinear system can contain frequencies different from those present in the influences. However, the point to emphasize here is that, as well as the generation of new frequencies, nonlinear optics provides the ability to control light with ...
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Ellipsometry

Ellipsometry is an optical technique for investigating the dielectric properties (complex refractive index or dielectric function) of thin films. Ellipsometry can be used to characterize composition, roughness, thickness (depth), crystalline nature, doping concentration, electrical conductivity and other material properties. It is very sensitive to the change in the optical response of incident radiation that interacts with the material being investigated.Typically, the measured signal is the change in polarization as the incident radiation (in a known state) interacts with the material structure of interest (reflected, absorbed, scattered, or transmitted). The polarization change is quantified by the amplitude ratio, Ψ, and the phase difference, Δ (defined below). Because the signal depends on the thickness as well as the materials properties, ellipsometry can be a universal tool for contact free determination of thickness and optical constants of films of all kinds.This technique has found applications in many different fields, from semiconductor physics to microelectronics and biology, from basic research to industrial applications. Ellipsometry is a very sensitive measurement technique and provides unequaled capabilities for thin film metrology. As an optical technique, spectroscopic ellipsometry is non-destructive and contactless. Because the incident radiation can be focused, small sample sizes can be imaged and desired characteristics can be mapped over a larger area (m^2).The one weakness of ellipsometry is the need to model the data. Entire courses are taught in the modeling of the raw data. Models can be physically based on energy transitions or simply free parameters used to fit the data.Upon the analysis of the change of polarization of light, ellipsometry can yield information about layers that are thinner than the wavelength of the probing light itself, even down to a single atomic layer. Ellipsometry can probe the complex refractive index or dielectric function tensor, which gives access to fundamental physical parameters like those listed above. It is commonly used to characterize film thickness for single layers or complex multilayer stacks ranging from a few angstroms or tenths of a nanometer to several micrometers with an excellent accuracy.The name ""ellipsometry"" stems from the fact that Elliptical polarization of light is used. The term ""spectroscopic"" relates to the fact that the information gained is a function of the light's wavelength or energy (spectra). The technique has been known at least since 1888 by the work of Paul Drude, (the term ""ellipsometry"" being first used probably in 1945 ) and has many applications today. A spectroscopic ellipsometer can be found in most thin film analytical labs. Ellipsometry is also becoming more interesting to researchers in other disciplines such as biology and medicine. These areas pose new challenges to the technique, such as measurements on unstable liquid surfaces and microscopic imaging.
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