Fizeau interferometer
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A Fizeau interferometer is a device to judge flatness of a surface. Many optical instrumentation are tested using Fizeau interferometry.
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Auto-collimator
An auto-collimator is an optical instrument that uses a collimator and telescope combined to measure small angular differences very sensitively and accurately. It works by projecting parallel light using a collimator and measuring the linear displacement of the reflected light when the reflector is tilted, which corresponds to twice the angle of tilt. The auto-collimator responds only to tilts of the reflector, and its focal length and aperture determine its measurement range and sensitivity. It can be used to measure straightness, flatness, angles, squareness, and parallelism.
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This document discusses different types of projections used in 3D viewing pipelines, including perspective and parallel projections. Perspective projections use a center of projection to project 3D points onto a 2D view plane, resulting in effects like foreshortening and vanishing points. Parallel projections project points parallel to a viewing direction, preserving scale and shape. Specific types of parallel projections discussed include orthographic, oblique, isometric, and axonometric projections.
Review of geometric optics
This document discusses various topics related to optics including vergence, conjugacy, object and image space, cardinal points, spherical mirrors, sign convention, and magnification. It defines convergence and divergence as types of vergence eye movements. It also defines types of lenses, mirrors, and their focal lengths, principal points, and power. Magnification is described as visually enlarging an object without physically changing its size through various optical instruments.
Light full chaptet 10 cbse x
The document discusses the laws of reflection and image formation using spherical mirrors. It defines key terms like normal, angle of incidence, angle of reflection, focal length, pole, radius of curvature, etc. Rules for image formation using concave and convex mirrors are explained along with diagrams. Characteristics of the image like nature, position and size are defined based on the position of the object in front of the concave mirror. Sign convention for spherical mirrors is also explained. Examples of questions from NCERT on image formation and characteristics are summarized.
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OPTICAL MICROSCOPY AND COORDINATE MEASURING MACHINE
Introduction
Working principle
Classification
Construction and working
Different types of an optical scope
Process capabilities and analysis
Testing
Process parameters
Components and machine structure
Confocal laser scanning microscopy
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Applications
Advancement in CMM
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Manual 3131904 EXPERIMENTS BE
1. The specimen is cut, mounted, and ground using progressively finer abrasive papers to create a flat surface.
2. The specimen is then polished using diamond and alumina powders to remove fine scratches.
3. Etching with chemical reagents is used to reveal microscopic structures by imparting contrast to grain boundaries and other microstructural features. This final prepared specimen surface can then be examined under a microscope.
Light grade 10 notes
This document provides information about light reflection and refraction. It defines key concepts such as the ray and beam of light. It describes the laws of reflection, including that the angle of incidence equals the angle of reflection. Plane mirrors form virtual, erect, and laterally inverted images. Spherical mirrors can be concave or convex and form real or virtual images depending on the position of the object. The document also covers the laws of refraction, including Snell's law, and discusses image formation using lenses. Convex lenses form real, inverted images while concave lenses form virtual, erect images. Lens formula and magnification are also defined.
09.Ray optics.pdf
Optics is the study of light and its interactions with matter. There are two main branches of optics: geometrical optics and physical optics. Geometrical optics considers light as rays and explains phenomena like reflection and refraction using laws of reflection. Physical optics considers light as electromagnetic waves and explains phenomena like interference and diffraction. Spherical mirrors come in two types - concave and convex. Concave mirrors form real, inverted images while convex mirrors form virtual, upright images. The mirror equation relates the object and image distances to the focal length.
Lenses
This document discusses lenses and their effects on light. It explains that a converging lens brings parallel beams of light to a focal point, forming a real image. A diverging lens causes parallel beams to diverge, with a virtual focal point behind the lens. Real and virtual images are formed by converging lenses using ray diagrams and optical rules. Applications like cameras and magnifying glasses are also covered.
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LIGHT_final.pptx
- Reflection of light occurs when a ray of light changes direction after striking a smooth surface without passing through. The angle of incidence equals the angle of reflection.
- Refraction occurs when light passes from one medium to another of different optical density, causing the ray to bend. The ratio of sines of angles of incidence and refraction is a constant called the refractive index.
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Illumination Engineering.pdf
This ppt presents you about what is illumination various types of illumination and types of lighting schemes in illumination.there are two main types of lighting one is natural lighting which occurs with the lighting of sun and artificial lighting which occurs due to the artificial sources of light such as bulbs,torches,tubes etc Artificial light sources are other sources of light which developed to compensate for or assist the natural light. It will have different frequencies and wavelengths that determine the light color.Artificial light sources are categorized by the technology used to produce the light. There's dozens of sources, with a few common in household applications and others more suitable for industrial uses. The five most common light sources are as follows:
Incandescent lamp.
Compact fluorescent lamp.
Fluorescent tube.
Discharge lamps.
Light Emitting Diode (LED).
Until recently the most common electric light source was the incandescent lamp. This is still widely used, although its relatively low energy efficiency is leading to its replacement by other more efficient lamps such as the CFL.
The connection to a light fitting is either by screw thread or bayonet.
A large variety of shapes, sizes and power is available, as well as different colour ranges. Typical lamps for household use range from about 40 to 100 W, giving a light output of 420 to 1360lm at the typical lamp efficiency of about 12%.
The compact fluorescent lamp (CFL) was designed as a more efficient replacement for incandescent lamp. It is supplied with the same fixing system (screw or bayonet), and can be used in many light fittings designed for incandescent lamps.
Power ratings of CFLs that can provide approximately the equivalent light output to incandescent lamps are shown in the table below, together with their efficacy ratings.
tube
Fluorescent tubes are the main form of lighting for offices and commercial buildings.
They are a form of gas discharge lamp, and are formed in a long thin glass cylinder with contacts at either end that secure them to the fitting (or luminaire) and provide the electrical connection.
The tube contains mercury vapour at low pressure, and the inner wall of the glass is coated with a phosphor that reacts to ultra-violet radiation. When electricity is passed through the vapour it emits UV radiation that is converted by the phosphor to visible light.
The most efficient fluorescent tubes are the T5. With a smaller diameter (16mm) than earlier tubes, these can achieve a luminous efficacy of up to 104lm/W
Discharge lamps work by striking an electrical arc between two electrodes, causing a filler gas to give off light.
Different metals and filler gasses can be used to provide a range of colour and brightness.
Discharge lamps provide high luminous efficacy combined with long life, resulting in the most economical light source available
Types of gas-discharge lamps:
The gas discharge lamps have three types as follows
Low pressure d
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This document provides an overview of light reflection and spherical mirrors. It begins with definitions of key concepts like reflection, convex mirrors, concave mirrors, and plane mirrors. Examples are given to illustrate the properties of each type of mirror. The key parts of spherical mirrors like the principal axis, focal point, and radius of curvature are summarized. Methods for predicting images using ray diagrams are described. The differences between images formed by concave and convex mirrors are explained. Finally, the mirror equation for calculating image properties is introduced along with sign conventions.
Module No. 39
1. A plane mirror forms a virtual image that is laterally inverted and the same size as the object. The image is located behind the mirror and an equal distance from the mirror as the object.
2. Spherical mirrors can be concave or convex. A concave mirror forms real or virtual images depending on the object position, while a convex mirror always forms a virtual, erect, and diminished image.
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Consider a glass with a hollow sphere and a reflecting surface. This reflecting hollow surface of sphere of which either sides are polished, forms the spherical mirrors. Spherical Mirrors are of two types: (a) Concave Mirror Copy the link given below and paste it in new browser window to get more information on Reflection of Light by Spherical Mirrors www.askiitians.com/iit-jee-ray-optics/reflection-of-light-by-spherical-mirrors/
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With increasing population, people need to rely on packaged food stuffs. Packaging of food materials requires the preservation of food. There are various methods for the treatment of food to preserve them and irradiation treatment of food is one of them. It is the most common and the most harmless method for the food preservation as it does not alter the necessary micronutrients of food materials. Although irradiated food doesn’t cause any harm to the human health but still the quality assessment of food is required to provide consumers with necessary information about the food. ESR spectroscopy is the most sophisticated way to investigate the quality of the food and the free radicals induced during the processing of the food. ESR spin trapping technique is useful for the detection of highly unstable radicals in the food. The antioxidant capability of liquid food and beverages in mainly performed by spin trapping technique.
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Fizeau interferometer
- 2. Principle Reflected light from reference plate and test flat produces interference patterns of different intensity •I = I1+ I2 + 2√(I1I2) cos f •The resultant intensity of reflected light is used to judge the nature of test surface.
- 3. Working and construction It comprises of a monochromatic light source (e.g. laser) passed through a pin-hole using a converging lens. The light then illuminates the objective, and because pin hole was at focus of this lens, light rays become parallel. Objective lens acts as collimator The parallel light emerging from collimator passes through high quality reference flat which is permanently built into the instrument.
- 4. Working and construction (cont.) The reflected light from reference flat and test flat undergo interference and pass through beam splitter to the eyepiece or CCD.
- 5. Guidelines and modifications The reference flat is adjusted till the image of pinhole disappears from screen/eyepiece. It is done so that reference flat is perpendicular to the parallel light beams. Reference flat is beveled (see Fig.) so that light reflected from that surface will not interfere with light coming from test flat. Fig. Beveling of reference flat
- 6. Applications Extensively used for testing optical components in space related instrumentation. E.g. primary mirrors in Hubble Space Telescope Checking optical flats, wedges, front surface mirrors and glasses are major applications.
- 7. Applications Fig. Testing spherical surface of the test lens with respect to reference spherical su
- 8. Applications Fig. Fizeau interferometer for measuring the effect of water movement upon the speed of light. The interference pattern can be analyzed to determine speed of light in each of the tube. This is the famous Fizeau experiment whose unexpected results were explained by Special Theory of Relativity.