optics

In photography and optics, vignetting refers to a reduction in image brightness in the image periphery compared to the image center. Vignetting is sometimes used for creative effect (e.g. to draw attention to the center of the frame). It is deliberately introduced by the photographer by the use of special filters or post-processing procedures. Vignetting is also used to describe unwanted darkening of the corner of a photograph. There are three different types of unwanted vignetting: Mechanical (or physical) vignetting Op ...

Read more here: » Vignetting: Encyclopedia - Vignetting

In mathematics, wavelets, wavelet analysis, and the wavelet transform refers to the representation of a signal in terms of a finite length or fast decaying oscillating waveform (known as the mother wavelet). This waveform is scaled and translated to match the input signal. In formal terms, this representation is a wavelet series, which is the coordinate representation of a square integrable function with respect to a complete, orthonormal set of basis functions for the Hilbert space of square integrable functions. ...

Including:

• Wavelet - Overview
• Wavelet - Using wavelet theory
• Wavelet - Mother wavelet
• Wavelet - Comparisons with Fourier
• Wavelet - Definition of a wavelet
• Wavelet - Scaling filter
• Wavelet - Scaling function
• Wavelet - Wavelet function
• Wavelet - Applications
• Wavelet - History
• Wavelet - Time line
• Wavelet - Wavelet transforms
• Wavelet - List of wavelets
• Wavelet - Discrete wavelets
• Wavelet - Continuous wavelets

Read more here: » Wavelet: Encyclopedia - Wavelet

Very Long Baseline Interferometry (VLBI) is a type of interferometry in which the data received at each antenna in the array is paired with timing information, usually from a local atomic clock, and then stored for later analysis on magnetic tape or hard disk. At that later time, the data are correlated with data from other antennas similarly recorded, to produce the resulting image. The resolution achievable using interferometry is proportional to the distance between the antennas furthest apart in the array. The VLBI technique enabl ...

Including:

• Very Long Baseline Interferometry - Space VLBI
• Very Long Baseline Interferometry - How VLBI Works

Read more here: » Very Long Baseline Interferometry: Encyclopedia - Very Long Baseline Interferometry

The term condenser has the following meanings: In electronics, it is a less-commonly used word for capacitor; more often found in non-electronic context, such as the automotive ignition system. A condenser microphone uses a capacitive diaphragm element to convert sound to electrical signals. In electrical engineering, a synchronous condenser is a rotating machine similar to a motor, used to control reactive power flow on an electric power transmission system. In chemistry, a condenser is the app

Read more here: » Condenser: Encyclopedia - Condenser

Where <> denotes an ensemble (statistical) average. For non-stationary states, such as pulses, the ensemble is made up of many pulses. When one deals with stationary states, where the statistical properties do not change with time, one can replace the ensemble average with a time average. If we restrict ourselves to plane parallel waves then . In this case, the result for stationary states will not depend on t1, but on the time delay τ = t1 − t2 (or if ). ...

See also:

Degree of coherence, Degree of coherence - Degree of first-order coherence, Degree of coherence - Examples of g¹, Degree of coherence - Degree of second-order coherence, Degree of coherence - Examples of g², Degree of coherence - Degree of nth-order coherence, Degree of coherence - Examples of gⁿ, Degree of coherence - Generalization to Quantum Fields, Degree of coherence - Examples of nonclassical states of light, Degree of coherence - Photon Bunching, Degree of coherence - Suggested reading

Read more here: » Degree of coherence: Encyclopedia II - Degree of coherence - Degree of first-order coherence

Poincaré was born on April 29, 1854 in Cité Ducale neighborhood, Nancy, France into an influential family (Belliver, 1956). His father Leon Poincaré (1828-1892) was a professor of medicine at the University of Nancy (Sagaret, 1911). His adored younger sister Aline married the spiritual philosopher Emile Boutroux. Another notable member of Jules' family was his cousin Raymond Poincaré, who would become the President of France 1913 to 1920 and a fellow member of the Académie française. See also:

Henri Poincaré, Henri Poincaré - Life, Henri Poincaré - Education, Henri Poincaré - Early career, Henri Poincaré - The three-body problem, Henri Poincaré - Work on relativity, Henri Poincaré - Section References, Henri Poincaré - Late career, Henri Poincaré - Character, Henri Poincaré - Toulouse' characterization, Henri Poincaré - Work, Henri Poincaré - Philosophy, Henri Poincaré - Honors, Henri Poincaré - Publications

Read more here: » Henri Poincaré: Encyclopedia II - Henri Poincaré - Life

The optical fiber can be used as a medium for telecommunication and networking because it is flexible and can be bundled as cables. Although fibers can be made out of either transparent plastic or glass, the fibers used in long-distance telecommunications applications are always glass, because of the lower optical attenuation. Both multi-mode and single-mode fibers are used in communications, with multi-mode fiber used mostly for short distances (up to 500 m), and single-mode fiber used for longer distance links. Because of the tighte ...

See also:

Optical fiber, Optical fiber - Optical description, Optical fiber - Materials, Optical fiber - Optical fiber communication, Optical fiber - Comparison with electrical transmission, Optical fiber - Governing standards, Optical fiber - Other uses of optical fibers, Optical fiber - Fiber Optic Sensors, Optical fiber - Manufacture, Optical fiber - Optical fiber cables, Optical fiber - History, Optical fiber - Footnotes

Read more here: » Optical fiber: Encyclopedia II - Optical fiber - Optical fiber communication

In content his work is distinguished by a certain definiteness and finality, and even of problems which, when he attacked them, were scarcely thought amenable to mathematical analysis, he has in many cases given solutions which once and for all settle the main principles. This fact must be ascribed to his extraordinary combination of mathematical power with experimental skill. From the time when in about 1840 he fitted up some simple physical apparatus in his rooms in Pembroke College, mathematics and experiment ever went hand in hand, aidin ...

See also:

George Gabriel Stokes, George Gabriel Stokes - Life, George Gabriel Stokes - Contributions to science, George Gabriel Stokes - List of Stokes eponymns, George Gabriel Stokes - Honours, George Gabriel Stokes - Published works, George Gabriel Stokes - Reference

Read more here: » George Gabriel Stokes: Encyclopedia II - George Gabriel Stokes - Contributions to science

The art and architecture of ancient Greece have greatly influenced Western art through the present day. Byzantine art and architecture also played an important role in early Christianity, and remain a significant influence in the Orthodox Christian nations of Eastern Europe and Eurasia. Yet, due to the ravages of history, only a minor assortment of ancient Greek art has survived - most often in the forms of sculpture and architecture and minor arts, including coin design, pottery and gem engraving. Culture of Greece - Architecture. Remains of ancient Greek architecture still survive or ...

See also:

Culture of Greece, Culture of Greece - Art and architecture, Culture of Greece - Architecture, Culture of Greece - Painting and sculpture, Culture of Greece - Pottery and coins, Culture of Greece - Literature, Culture of Greece - Religion, Culture of Greece - Philosophy science and mathematics, Culture of Greece - Music, Culture of Greece - Cuisine, Culture of Greece - Sports

Read more here: » Culture of Greece: Encyclopedia II - Culture of Greece - Art and architecture

The complete surviving works are Pneumatica (Greek, c. 60), Automata (Greek), Mechanics (Arabic), Metrics (Arabic), Dioptra (Arabic). In optics, Hero proposed that light travels along the shortest geometric path. This view is no longer accepted, having been replaced by the least-time principle. In geometry, the formula for finding the area of any triangle knowing only the lengths of its sides is known as Hero's or Heron's Formula. wher ...

See also:

Hero of Alexandria, Hero of Alexandria - Publications, Hero of Alexandria - Projects

Read more here: » Hero of Alexandria: Encyclopedia II - Hero of Alexandria - Publications

From the very beginning, the foundation of Islamic civilization was urban and business oriented, and its growth in population and agriculture is mirrored through its global trade network. Muslim cities grew unregulated, resulting in narrow winding city streets and neighborhoods separated by different ethnic backgrounds and religious affiliations. These qualities proved efficient for transporting goods to and from major commercial centers while preserving the privacy valued by Islamic family life. Suburbs lay just outside the walled city, fro ...

See also:

Islamic Golden Age, Islamic Golden Age - Foundations, Islamic Golden Age - Islamic art, Islamic Golden Age - Philosophy, Islamic Golden Age - Sciences, Islamic Golden Age - Medicine, Islamic Golden Age - Commerce and urban life, Islamic Golden Age - Architecture and engineering, Islamic Golden Age - Mongolian invasion and gradual decline, Islamic Golden Age - Opposing views

Read more here: » Islamic Golden Age: Encyclopedia II - Islamic Golden Age - Commerce and urban life

F developed from the digraph FH that stood for /f/. The Etruscans were the inventors of this digraph; F on its own stood for /w/ in Etruscan as in Greek (where the letter F, called Digamma in Greek, has disappeared due to the fact that the /w/ phoneme itself disappeared.) The origin of F is the Semitic letter wâw that also represented /w/ and originally probably represented a hook or a club. The minuscule f is not to be confused with ſ, the archaic long s (or medial s). For example, "sinfuln ...

See also:

F, F - History, F - Phonetic use, F - Codes for computing, F - Ligatures, F - Meanings for F, F - Variants of F

Read more here: » F: Encyclopedia II - F - History

In November 1894 J.C. Bose ignited gunpowder and rang a bell at a distance using electromagnetic waves, confirming that communication signals can be sent without using wires. This was one year after Nikola Tesla made the first public demonstration of radio communication in 1893. Bose went to London on a lecture tour in 1896 and met Marconi, who was conducting wireless experiments for the British post office. In an interview, Bose said he was not interested in commercial telegraphy and others can use his research work. Later in 1899 Bose announced his invention of the "iron-mercury-iron coherer with telephone d ...

See also:

Jagdish Chandra Bose, Jagdish Chandra Bose - Early life, Jagdish Chandra Bose - Radio research, Jagdish Chandra Bose - Career as a teacher, Jagdish Chandra Bose - Plant research, Jagdish Chandra Bose - Legacy, Jagdish Chandra Bose - Publications, Jagdish Chandra Bose - Honors

Read more here: » Jagdish Chandra Bose: Encyclopedia II - Jagdish Chandra Bose - Radio research

Voltaire - Early years. Voltaire was born in Paris, France in 1694, the son of a notary (one who certifies legal documents) named Francois Arouet and his wife, Marie Marguerite D'Aumard. Most of Arouet's life revolved around Paris until his exile. He studied at the Collège Louis-le-Grand, where his education of the arts began. However, he claimed to not have learned anything other than "Latin and the Stupidities." Voltaire spent eight years there, where, despite his disdain, the school allowed for his development of literary talen ...

See also:

Voltaire, Voltaire - Biography, Voltaire - Early years, Voltaire - Exile to England, Voltaire - The Château de Cirey, Voltaire - Ferney and final years, Voltaire - Works, Voltaire - Plays, Voltaire - Poetry, Voltaire - Prose and romances, Voltaire - Historical, Voltaire - Philosophy, Voltaire - Correspondence, Voltaire - Miscellanous, Voltaire - Legacy, Voltaire - Quotations

Read more here: » Voltaire: Encyclopedia II - Voltaire - Biography

Gibbs' scientific career can be divided into four phases. Up until 1879, he worked on the theory of thermodynamics. From 1880 to 1884, he worked on the field of vector analysis. From 1882 to 1889, he worked on optics and the electromagnetic theory of light. After 1889, he worked on statistical mechanics, laying a foundation and "providing a mathematical framework for quantum theory and for Maxwell's theories" [1]; he also produced classic textbooks on the matter. See also:

Josiah Willard Gibbs, Josiah Willard Gibbs - Biography, Josiah Willard Gibbs - Early years, Josiah Willard Gibbs - Middle years, Josiah Willard Gibbs - Later years, Josiah Willard Gibbs - Death and afterwards, Josiah Willard Gibbs - Scientific recognition, Josiah Willard Gibbs - External articles and references, Josiah Willard Gibbs - Citations, Josiah Willard Gibbs - General

Read more here: » Josiah Willard Gibbs: Encyclopedia II - Josiah Willard Gibbs - Biography

James Clerk Maxwell - Early years. Maxwell was born at 14 India Street, Edinburgh, Scotland. He was the only child of Edinburgh lawyer John Clerk. Maxwell's early education was provided by his Christian mother and included studying the Bible. Most of his early childhood was spent at the family estate Glenlair near Dumfries. Maxwell's mother died when he was just eight years old. Maxwell then went to Edinburgh Academy in his youth. His school nickname was "Dafty", earned when he arrived for his first day of school ...

See also:

James Clerk Maxwell, James Clerk Maxwell - Biography, James Clerk Maxwell - Early years, James Clerk Maxwell - Middle years, James Clerk Maxwell - Later years and afterwards, James Clerk Maxwell - Poetry and song, James Clerk Maxwell - Publications, James Clerk Maxwell - Honours, James Clerk Maxwell - Links resources and references

Read more here: » James Clerk Maxwell: Encyclopedia II - James Clerk Maxwell - Biography

Carl Friedrich Gauss - Early years. Gauss was born in Brunswick, in the Duchy of Brunswick-Lüneburg (now part of Lower Saxony, Germany), as the only son of uneducated lower-class parents. According to legend, his gifts became apparent at the age of three when he corrected, in his head, an error his father had made on paper while calculating finances. Another story has it that in elementary school his teacher tried to occupy pupils by making them add up the integers from 1 to 100. The young Gauss produced the cor ...

See also:

Carl Friedrich Gauss, Carl Friedrich Gauss - Biography, Carl Friedrich Gauss - Early years, Carl Friedrich Gauss - Middle years, Carl Friedrich Gauss - Later years death and afterwards, Carl Friedrich Gauss - Family, Carl Friedrich Gauss - Personality, Carl Friedrich Gauss - Commemorations

Read more here: » Carl Friedrich Gauss: Encyclopedia II - Carl Friedrich Gauss - Biography

Isaac Newton - Early years. For more details on this topic, see Isaac Newton's early life and achievements. Newton was born in Woolsthorpe-by-Colsterworth (at Woolsthorpe Manor), a hamlet in the county of Lincolnshire. Newton was prematurely born and no one expected him to live; indeed, his mother, Hannah Ayscough Newton, is reported to have said that his body at that time could have fit inside a quart mug (Bell, 1937). His father, Isaac, had died three months before Newton's birth. When Newton was two years old, his mother went to live with her new husband, leavi ...

See also:

Isaac Newton, Isaac Newton - Biography, Isaac Newton - Early years, Isaac Newton - Middle years, Isaac Newton - Later life, Isaac Newton - Religious views, Isaac Newton - Newton's effect on religious thought, Isaac Newton - Newton versus the counterfeiters, Isaac Newton - Enlightenment philosophers, Isaac Newton - Newton's legacy, Isaac Newton - Newton's apple, Isaac Newton - Writings by Newton, Isaac Newton - Notes, Isaac Newton - Resources, Isaac Newton - References, Isaac Newton - Further reading, Isaac Newton - External links

Read more here: » Isaac Newton: Encyclopedia II - Isaac Newton - Biography

History of science in the Middle Ages - Early Middle Ages. See also: Medieval medicine, Medieval philosophy With the loss of the Western Roman Empire, much of Europe lost contact with the knowledge of the past. While the Byzantine Empire still held learning centers such as Alexandria and Constantinople, Western Europe's knowledge was concentrated in monasteries. Philosophical and scientific teaching of the period was based upon few copies and commentaries of ancient Greek texts that remained in West ...

See also:

History of science in the Middle Ages, History of science in the Middle Ages - The Middle Ages: Eastern World, History of science in the Middle Ages - Islamic science, History of science in the Middle Ages - Developments in China, History of science in the Middle Ages - The Middle Ages: Western World, History of science in the Middle Ages - Early Middle Ages, History of science in the Middle Ages - High Middle Ages, History of science in the Middle Ages - Late Middle Ages, History of science in the Middle Ages - Links

Read more here: » History of science in the Middle Ages: Encyclopedia II - History of science in the Middle Ages - The Middle Ages: Western World

On December 21, 1671 he was proposed as a candidate for admission into the Royal Society by Dr Seth Ward, bishop of Salisbury, and on January 11, 1672 he was elected a fellow of the Society. At the meeting at which Newton was elected, he read a description of a reflecting telescope which he had invented, and "it was ordered that a letter should be written by the secretary to Mr Newton to acquaint him of his election into the Society, and to thank him for the communication of his telescope, and to assure him that t ...

See also:

Isaac Newton's early life and achievements, Isaac Newton's early life and achievements - Birth and education, Isaac Newton's early life and achievements - Academic career, Isaac Newton's early life and achievements - The composition of white light, Isaac Newton's early life and achievements - Newton's theory of colour, Isaac Newton's early life and achievements - Controversies, Isaac Newton's early life and achievements - Conflict over oratorship elections, Isaac Newton's early life and achievements - Newton's poverty, Isaac Newton's early life and achievements - Universal law of gravitation

Read more here: » Isaac Newton's early life and achievements: Encyclopedia II - Isaac Newton's early life and achievements - The composition of white light

The Cornu spiral, a.k.a. clothoid, is the curve generated by a parametric plot of S(x) against C(x). The Cornu spiral was created by Marie Alfred Cornu as a nomogram for diffraction computations in science and engineering. It is a logical shape with a varying radius, in use for the transition of a straight to a circle curve in roads and railways because a vehicle following the curve at constant speed will have a constant rotational acceleration, reducing lateral stress on the rail tracks, however it may not be the ideal transition spiral, especially at higher speeds ...

See also:

Fresnel integral, Fresnel integral - Cornu spiral, Fresnel integral - Error function

Read more here: » Fresnel integral: Encyclopedia II - Fresnel integral - Cornu spiral

Two of the earliest explanations of the optical spectrum came from Newton, when he wrote his Optiks, and from Goethe, in his Theory of Colours. Isaac Newton first used the word spectrum (Latin for "appearance" or "apparition") in print in 1671 in describing his experiments in optics. Newton observed that, when a narrow beam of white sunlight strikes the face of a glass prism at an angle, some is reflected and some of the beam passes into and through the glass, emerging as different colored bands. Newton hypothesized that light ...

See also:

Visible spectrum, Visible spectrum - Historical use of the term, Visible spectrum - Spectroscopy

Read more here: » Visible spectrum: Encyclopedia II - Visible spectrum - Historical use of the term