Nature and behaviour of light
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joLight can vibrate in one plane (be polarized) through selective absorption or reflection. When light passes from one medium to another of different density, some of the light will be reflected and some will pass through but be bent and slowed down (refracted). The angle of reflection equals the angle of incidence, while the angle of refraction depends on the change in velocity. Minerals can be characterized by their index of refraction (n), which is a measure of how much light is bent when passing into the mineral. It determines properties like relief and birefringence. Some minerals like calcite have the property of double refraction, where a single ray of light enters and splits into two rays.
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Polarization of Light and its Application (healthkura.com)
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polarization of light & its application.
PRESENTATION LAYOUT
Concept of Polarization
Types of Polarization
Methods of achieving Polarization
Applications of Polarization
POLARIZATION
Transforming unpolarized light into polarized light
Restriction of electric field vector E in a particular plane so that vibration occurs in a single plane
Characteristic of transverse wave
Longitudinal waves can’t be polarized; direction of their oscillation is along the direction of propagation.............
For Further Reading
•Optics by Tunnacliffe
•Optics and Refraction by A.K. Khurana
•Principle of Physics, Ayam Publication
•Internet
Magnetic and non magnetic
The document discusses magnetic and non-magnetic materials. Magnetic materials include metals like iron, nickel, cobalt and steel that are attracted to magnets. Non-magnetic materials that are not attracted to magnets include aluminum, silver, gold, paper, glass, plastic, rubber and wood. The document provides examples of different objects and whether they are magnetic or non-magnetic when tested with a magnet.
Module 3 the nature and properties of light
Here are the answers to the self-test:
1. Real image
2. Angle of incidence
3. Convex mirror
4. Focal length
5. Plane mirror
6. Between the center of curvature and the focus
7. At the principal focus
8. Vertex
Light.ppt
Light travels in straight lines until interacting with objects. It can scatter, reflect, refract, or be absorbed. Reflection causes light to bounce off a surface at the same angle. Refraction causes light to change speed and direction when passing from one medium to another, such as from water to air. Absorption occurs when light is taken in by an object and its energy is transferred to heat.
10 properties of light
The document discusses several key properties of light, including:
- Reflection - Light bounces off surfaces at the same angle it hits.
- Refraction - Light bends as it passes from one medium to another, changing speed. The degree of bending depends on the medium's index of refraction.
- Interference - When two light waves meet, they can constructively or destructively interfere based on how their crests and troughs align.
It explores light's dual nature as both a wave and particle, demonstrated through experiments like Young's double-slit experiment showing light's wave-like interference patterns, and the photoelectric effect showing its particulate properties.
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Polarization of Light and its Application (healthkura.com)
Polarization of Light and its Application (healthkura.com)
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Chapter-6 Geol 2031 Optical Mineralogy.pptx
This document provides an overview of optical mineralogy and outlines topics to be covered in the chapter, including light properties, examining crystals under plane-polarized light and crossed polars, and refractive index determination. Key concepts are isotropic and anisotropic crystals, uniaxial and biaxial indicators, and examining crystals under convergent light. Objectives are to understand light properties and examination of minerals under different light conditions. Key examination techniques are described for isotropic, uniaxial, and biaxial crystals.
L 10 onwards Optical Mineralogy (2).pptx
The document discusses optical mineralogy and the use of the petrographic microscope. It introduces key optical concepts such as isotropic, uniaxial, and biaxial minerals. It explains how to determine optic sign using a gypsum plate and describes the relationship between birefringence and interference colors. Different orientations of mineral grains are illustrated using the optical indicatrix, which models how light propagates through a crystal. Biaxial minerals require three refractive indices and have an acute bisected angle (2V) that indicates optic sign. Understanding these optical phenomena aids in mineral identification.
OPTOMETRY - Part V POLARIZATION OF LIGHT
This article describes the principle and phenomenon of polarization of light. This article also illustrates on Birefringence, Dichroism and crossed polarizers.
Malu's Law is elaborated here as prerequisite to understand Polarization along with Brewster's Angle. Polarization by reflection and polarization by refraction are also discussed here for quick comprehension of the readers.
Optical rotatory dispersion
The document discusses optical rotatory dispersion (ORD) and circular dichroism. It begins by introducing Sujit R. Patel from the Department of Pharmaceutics and provides an overview of topics to be covered including ORD, the ORD curve, circular dichroism, and the octant rule. It then discusses the fundamentals of ORD, how specific rotation changes with wavelength, and the different types of ORD curves including plain and anomalous curves. It also addresses the cotton effect seen in anomalous dispersion curves. Finally, it covers applications of circular dichroism spectroscopy such as determining protein and nucleic acid conformation.
Bhu 19 pet_solved_3
This document discusses isotropic and anisotropic minerals and the optical phenomenon of double refraction. It begins by explaining that anisotropic crystals split light into two polarized rays with different velocities and refractive indices, called the ordinary and extraordinary rays. Double refraction, where two images are seen, is characteristic of anisotropic minerals like calcite. Isotropic minerals like those in the cubic crystal system do not exhibit double refraction and appear black under crossed polarized light. The document provides examples and explanations of these optical properties.
Rupendra polarization ppt (7 jan2010)2007
This document discusses polarization of light. There are three types of polarized light: plane polarized light, circularly polarized light, and elliptically polarized light. Plane polarized light has vibrations confined to a definite plane. Circularly polarized light results from the superposition of two plane polarized light waves with a phase difference of π/2, giving a constant magnitude vector that varies in orientation. Elliptically polarized light results from two plane polarized waves with different amplitudes and a phase difference of π/2, giving a varying magnitude and orientation vector. Polarized light can be produced through reflection, refraction, selective absorption, scattering, and double refraction. Polarizers, quarter wave plates, and half wave plates are used
POLARIZATION.pptx
Polarization refers to the orientation of oscillations in light waves. Light can be linearly polarized, circularly polarized, or elliptically polarized depending on the orientation. Polarization occurs through reflection, refraction, and double refraction in anisotropic materials. Polarizers and waveplates can be used to alter the polarization state. Some materials exhibit optical activity and can rotate the plane of polarized light through either dextrorotation or levorotation. Specific rotation is a measure of the degree of optical activity for a substance.
Polarization and it's application in Ophthalmology
Polarization, types of polarization, mechanisms to produce polarization, Applications of polarization, precautions with polarizing sunglasses, ophthalmic uses of polarization
CD & ORD Spectrometer
A detail and straight forward information about th CD and ORD
and Also about the polarization of light i.e. plane polarized light and circular polarized light
Polarisation
Polarization of light, Types of Polarization, Plane polarized light and its production, Circular Polarization, Elliptical Polarization, E -ray , O-ray, Positive and negative crystals, Quarter wave plate and half wave plate.
Prabhakar singh ii sem-paper v-optical methods for determination of molecula...
Prabhakar singh ii sem-paper v-optical methods for determination of molecula...Department of Biochemistry, Veer Bahadur Singh Purvanchal Univarsity, Jaunpur
The document discusses several optical techniques for determining molecular structure, including polarized light, absorption of polarized light, optical rotatory dispersion, hypochromism, circular dichroism, and vibrational circular dichroism. Polarized light waves have vibrations that occur in a single plane. Optical rotatory dispersion measures the variation in optical rotation with wavelength change and can be used to identify absorption bands. Circular dichroism measures the difference in absorption of left and right circularly polarized light and can provide information about protein and nucleic acid structure. Vibrational circular dichroism extends this technique to the infrared and near infrared to allow determination of absolute configurations of small molecules.POLARIZATION - BIREFRINGENCE AND HUYGEN'S THEORY OF DOUBLE REFRACTION
SIMPLE AND ACCESSIBLE SLIDES ON POLARIZATION. IT INCLUDES SLIDES ON DOUBLE REFRACTION , CALCITE CRYSTALS, HUYGEN'S THEORY , NEGATIVE AND POSITIVE CRYSTALS,...
ORD CD AMU notes.pdf
Optical rotatory dispersion (ORD) measures the change in optical rotation of a substance with changing wavelength of light. ORD can be used to determine the absolute configuration of chiral molecules like metal complexes. When plane-polarized light passes through a chiral substance, the left and right circularly polarized components propagate at different speeds, leading to optical rotation. Measuring optical rotation as a function of wavelength is ORD spectroscopy. The Cotton effect occurs near absorption bands, where peaks and troughs in the ORD curve depend on whether absorption first increases or decreases with wavelength. Applications of ORD and circular dichroism include determining structures of amino acids, proteins, steroids and antibiotics.
Optical properties of gems
1. Refractive index is a measure of how light propagates through a material and is calculated as the ratio of the speed of light in vacuum to the speed of light in the material. It is a unique property useful for mineral identification.
2. The refractometer is an instrument used to measure refractive index based on the phenomenon of total internal reflection. It consists of a glass prism with a known refractive index that allows measurement of the critical angle and calculation of the unknown refractive index of a material.
3. Refractive index can vary with wavelength, so it is conventionally measured using yellow sodium light. Values range from around 1.4 to 2.4 for most gemstones. Refractometers with different
Optical properties of gems
1. The document discusses optical properties of minerals such as transparency, refractive index, colour, and luminescence. It explains how these properties are useful for identifying minerals.
2. Refractive index is a measure of how light propagates through a mineral and is calculated based on the angle of refraction. It varies between minerals based on their atomic structure.
3. A refractometer uses the phenomenon of total internal reflection at the critical angle to directly measure a mineral's refractive index, which is an important property for identification. The critical angle is the maximum angle at which light can pass from a dense medium into a rare medium.
Lecture 9a 2013_
This document provides an overview of matrix concepts and their application to optics. It discusses:
1) How matrices can be used to represent optical systems and describe the propagation of light rays through multiple components using basic operations like translation and refraction.
2) Common matrix representations for optical elements like lenses, mirrors, and polarization elements. The determinant of cascaded matrices can be used to describe properties of the overall optical system.
3) How Jones matrices represent the change in polarization state of light passing through or reflecting off an optical element, allowing polarization effects to be analyzed.
COLOR_OF_LIGHTS.ppt
Electromagnetic waves interact with materials in several ways that determine the color perceived. Color arises from emission, reflection, transmission, interference, dispersion, and scattering of light waves interacting with objects. The primary colors of light are red, green and blue, which combine to make white light. The primary colors of pigment are cyan, yellow and magenta, which combine to make black. Reflection, refraction, polarization, and interference cause the wide variety of colors observed from different materials due to the interaction of light waves.
ORD & CD Spectroscopy
Optical rotatory dispersion (ORD) measures the angle of rotation of plane-polarized light after it passes through a chiral substance. Circular dichroism (CD) measures the differential absorption of left and right circularly polarized light by some materials. ORD spectra are dispersive and show the specific rotation versus wavelength, while CD spectra are absorptive and plot molar ellipticity versus wavelength. Both techniques exploit the fact that chiral molecules interact differently with left and right circularly polarized light.
Polarization ppt
This is a ppt on polarization. This ppt gives the information about polarization and double refraction
Polarization
This presentation discusses polarization of light and its applications. It defines polarization as restricting the electric field vector of light to vibrate in a single plane. There are three main types of polarization: linear, circular, and elliptical. Polarization can be achieved through reflection, scattering, dichroism, and birefringence. Some applications of polarized light include polarized sunglasses, photographic filters, LCD screens, and 3D films.
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Polarization and it's application in Ophthalmology
Polarization and it's application in Ophthalmology
Prabhakar singh ii sem-paper v-optical methods for determination of molecula...
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POLARIZATION - BIREFRINGENCE AND HUYGEN'S THEORY OF DOUBLE REFRACTION
POLARIZATION - BIREFRINGENCE AND HUYGEN'S THEORY OF DOUBLE REFRACTION
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Amphiboles
The amphiboles are a group of chain silicate minerals with some substitution of F and Cl for OH. They have a general formula of (W,X,Y)7-8(Z4O10)2(OH)2 where W represents large cations like Ca and Na, X represents smaller cations like Mg and Fe2+, Y represents Fe3+, Ti, and Al, and Z represents Si and Al. Amphiboles have elongate prismatic crystals and two prismatic cleavages that meet at 124 degrees, whereas pyroxenes have squat prisms and cleavages that meet at 88 degrees. Common amphiboles include hornblende, tremolite, actinolite
Amphiboles
The amphiboles are a group of chain silicate minerals with some substitution of F and Cl for OH. They have a general formula of (W,X,Y)7-8(Z4O10)2(OH)2 where W represents large cations like Ca and Na, X represents smaller cations like Mg and Fe2+, Y represents Fe3+, Ti, and Al, and Z represents Si and Al. Amphiboles have elongate prismatic crystals and two prismatic cleavages that meet at 124 degrees, whereas pyroxenes have squat prisms and cleavages that meet at 88 degrees. Common amphiboles include hornblende, tremolite, actinolite
Amphiboles
The amphiboles are a group of chain silicate minerals with some substitution of F and Cl for OH. They have a general formula of (W,X,Y)7-8(Z4O10)2(OH)2 where W represents large cations like Ca and Na, X represents smaller cations like Mg and Fe2+, Y represents Fe3+, Ti, and Al, and Z represents Si and Al. Amphiboles have elongate prismatic crystals and two prismatic cleavages that meet at 124 degrees, whereas pyroxenes have squat prisms and cleavages that meet at 88 degrees. Common amphiboles include hornblende, tremolite, actinolite
Amphiboles
The amphiboles are a group of chain silicate minerals with some substitution of F and Cl for OH. They have a general formula of (W,X,Y)7-8(Z4O10)2(OH)2 where W represents large cations like Ca and Na, X represents smaller cations like Mg and Fe2+, Y represents Fe3+, Ti, and Al, and Z represents Si and Al. Amphiboles are distinguished from pyroxenes by having a different Si:O ratio and containing essential OH groups in their structure. Common amphiboles include hornblende, tremolite, actinolite, anthophyllite, cummingtonite, grunerite,
Amphiboles
The amphiboles are a group of chain silicate minerals with some substitution of F and Cl for OH. They have a general formula of (W,X,Y)7-8(Z4O10)2(OH)2 where W represents large cations like Ca and Na, X represents smaller cations like Mg and Fe2+, Y represents Fe3+, Ti, and Al, and Z represents Si and Al. Amphiboles have elongate prismatic crystals and two prismatic cleavages that meet at 124 degrees, whereas pyroxenes have squat prisms and cleavages that meet at 88 degrees. Common amphiboles include hornblende, tremolite, actinolite
Nature and behaviour of light
Light can vibrate in one plane (be polarized) through selective absorption or reflection. When light passes from one medium to another of different density, some of the light will be reflected and some will pass through but be bent and slowed down (refracted). The angle of reflection equals the angle of incidence, while the angle of refraction depends on the change in velocity.
The index of refraction and relief of a mineral are used to identify it. Index of refraction is a measure of how light slows down when passing into a mineral and is related to its crystal structure. Relief refers to the difference in index of refraction between a mineral and its surroundings, and is used to estimate the index of ref
Copy of nature and behaviour of light
Light can vibrate in one plane (be polarized) through selective absorption or reflection. When light passes from one medium to another of different density, some of the light will be reflected and some will pass through but be bent and slowed down (refracted). The angle of reflection equals the angle of incidence, while the angle of refraction depends on the change in velocity.
The index of refraction and relief of minerals can be used to identify them. Index of refraction refers to how much light is refracted when passing from one substance to another. It varies based on crystallographic orientation in anisotropic minerals. Relief and birefringence are properties related to the index of refraction.
Space lattices
Crystals have basic building blocks called unit cells that are arranged in a periodic pattern described by a lattice. The unit cells contain motif groups of atoms associated with each lattice point. There are 14 possible types of space lattices belonging to 7 crystal systems characterized by distinct unit cell shapes and symmetries. The crystal structure is defined by the space lattice and the motif or basis group of atoms.
Rhombohedron
The document summarizes different crystallographic forms in the trigonal and tetragonal crystal systems. It describes rhombohedrons as solids bounded by six rhomb-shaped faces, and scalenohedrons as solids bounded by 8 or 12 scalene triangle faces. It also discusses sphenoids as four-faced solids resembling tetrahedrons but with isosceles triangle faces, and tetragonal scalenohedrons bounded by eight similar scalene triangles.
Presentation1
Crystals are defined as a 3D periodic arrangement of atoms in space, known as a lattice, with a motif or basis of atoms associated with each lattice point. A lattice is a 3D periodic arrangement of points without the atoms. Together, the lattice and motif define the crystal structure. There are 14 possible lattice arrangements, known as Bravais lattices, which are categorized into 7 crystal systems based on their symmetry properties. The lattice and basis completely specify the crystal structure.
Forms of crystals.
This document describes several crystal classes and forms. It discusses:
1) The pyritahedral class which includes forms like the pyritahedron and diploid bounded by 12 or 24 faces respectively.
2) The tetrahedral class including forms like the tetrahedron, deltoid dodecahedron, trigonal tristetrahedron, and hextetrahedron bounded by 4, 12, 12, and 24 faces.
3) Prism forms in the tetragonal, hexagonal, and orthorhombic crystal systems defined by their faces being parallel to the c-axis including first, second, and third order prisms.
Crystal structure
This document discusses crystal structures, including periodic arrays of atoms, fundamental lattice types, crystal planes indexed using Miller indices, and imaging atomic structures. It covers common lattice types like simple cubic, body-centered cubic, and face-centered cubic. Simple crystal structures presented include sodium chloride, cesium chloride, diamond, and zinc sulfide. Non-ideal crystal structures can involve random stacking or polytypism with long repeat units along stacking axes.
Crystal forms.
The document describes several common crystal forms including the cube, octahedron, and rhomb-dodecahedron. It provides details on the number of faces, their shapes, and how they intersect the crystallographic axes for each crystal form. Some common crystal forms mentioned are the cube, octahedron, rhomb-dodecahedron, tetrahexahedron, trapezohedron, trisoctahedron, hexoctahedron, pyritohedron, diploid, and tetrahedron.
Feldspar
Feldspar is the most abundant mineral group found in igneous and metamorphic rocks. It has a continuous three-dimensional network structure of silicon-oxygen and aluminum-oxygen tetrahedra with positively charged sodium, potassium, calcium, or barium ions situated between. The two most common feldspar types are orthoclase (potassium feldspar) and plagioclase (sodium-calcium feldspar). Plagioclase can form as a solid solution or break down into intergrowths of sodic and potassic lamellae called perthites. Feldspars are found in a wide range of igneous and metamorphic rocks depending on their
Silica
Quartz is one of the most abundant minerals and is composed of silicon dioxide (SiO2). It has a complex crystal structure and exists in several polymorphs including alpha-quartz, beta-quartz, tridymite, cristobalite, coesite, and stishovite. The stability of these polymorphs depends on temperature and pressure conditions. Cryptocrystalline varieties of quartz include chalcedony, agate, jasper, chert, and flint. Macrocrystalline varieties include rock crystal, milky quartz, amethyst, rose quartz, citrine, and smoky quartz.
Pyroxene
The document discusses the pyroxene group of minerals. Pyroxenes have a single chain crystal structure and are ionosilicates containing elements like calcium, sodium, magnesium, iron, and aluminum. They can be orthorhombic or monoclinic in crystal form. The general chemical formula of pyroxenes is (W,X,Y)2Z2O6, where W, X, Y, and Z can be elements like calcium, magnesium, iron, aluminum, sodium, lithium, silicon, and more. Some common pyroxenes mentioned include enstatite, hypersthene, diopside, hedenbergite, augite, and pigeonite.
Mica group
This document summarizes several types of phyllosilicate minerals in the mica group, including their chemical formulas, crystal structures, and common occurrences. Muscovite, biotite, and phlogopite are some of the most common micas. They have layered structures and perfect basal cleavage. Muscovite is widely used in electrical and insulation applications due to its properties. The document also describes lepidolite and its identification by lithium content and lilac color.
Feldspathoids
Feldspathoids are silicate minerals that are chemically similar to feldspars but deficient in silica. They form in place of feldspars when magma lacks sufficient silica. Common feldspathoids include leucite, nepheline, sodalite, cancrinite, and analcime. Some feldspathoids contain unusual anions like chloride, carbonate, sulfate, or sulfide. Leucite is characteristic of potassium-rich volcanic rocks. Nepheline occurs in both plutonic and volcanic alkaline, silica-poor rocks. Sodalite forms blue veinlets and masses and is found in nepheline syenites and phonolites.
Forms of crystals.
This document describes several crystal classes and forms. It discusses:
1) The pyritahedral class which includes forms like the pyritohedron bounded by 12 faces and the diploid bounded by 24 faces.
2) The tetrahedral class including the tetrahedron bounded by 4 faces and the deltoid dodecahedron bounded by 12 quadrilateral faces.
3) Different types of prisms in the tetragonal, hexagonal, and orthorhombic crystal systems defined by their orientation relative to the crystal axes and number of faces.
Crystal structure
This document discusses crystal structures, including periodic arrays of atoms, fundamental lattice types, crystal planes indexed using Miller indices, and imaging atomic structures. It covers common lattice types like simple cubic, body-centered cubic, and face-centered cubic. Simple crystal structures presented include sodium chloride, cesium chloride, diamond, and zinc sulfide. Non-ideal crystal structures can involve random stacking or polytypism with long repeat units along stacking axes.
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Nature and behaviour of light
- 1. Nature and Behaviour of Light
- 6. Anisotropic crystals Double images Ray 2 rays with different propagation and vibration directions Each is polarized ( each other) Fig 6-7 Bloss, Optical Crystallography, MSA Calcite experiment and double refraction O E