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Fisheye Lens
A fisheye lens is an ultra wide angle lens, ultra wide-angle lens that produces strong Distortion (optics), visual distortion intended to create a wide panorama, panoramic or Sphere#Hemisphere, hemispherical image. Fisheye lenses achieve extremely wide angle of view, angles of view, well beyond any rectilinear lens. Instead of producing images with straight lines of perspective (rectilinear lens, rectilinear images), fisheye lenses use a special mapping ("distortion"; for example: Lambert azimuthal equal-area projection, equisolid angle, see below), which gives images a characteristic convex non-rectilinear appearance. The term ''fisheye'' was coined in 1906 by American physicist and inventor Robert W. Wood based on how a fish would see an ultrawide hemispherical view from beneath the water (a phenomenon known as Snell's window). Their first practical use was in the 1920s for use in meteorology to study cloud formation giving them the name ''whole-sky lenses''. The angle of view ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ultra Wide Angle Lens
An ultra wide-angle lens is a Photographic lens, lens whose focal length is shorter than that of an average wide-angle lens, providing an even wider view. The term denotes a different range of lenses, relative to the size of the sensor in the camera in question. * For 1" any 9mm or shorter is considered ultra wide angle. * For Four Thirds system, 4/3" any 10 mm or shorter lens is considered ultra wide angle. * For APS-C any lens shorter than 15 mm. * For 35mm format, 35mm film or full-frame sensor any lens shorter than 24 mm * For Medium format (film), 6x4.5 cm any lens shorter than 41 mm * For Medium format (film), 6x6 cm and Medium format (film), 6x7 cm any lens shorter than 56 mm Features 'Fisheye' and rectilinear lenses Ultra-wide angle lenses come in two varieties: Fisheye lenses with curvilinear perspective, curvilinear barrel distortion, and rectilinear lenses which are designed so that straight lines in the scene will render straight (uncurv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CMOS
Complementary metal–oxide–semiconductor (CMOS, pronounced "sea-moss ", , ) is a type of MOSFET, metal–oxide–semiconductor field-effect transistor (MOSFET) semiconductor device fabrication, fabrication process that uses complementary and symmetrical pairs of p-type semiconductor, p-type and n-type semiconductor, n-type MOSFETs for logic functions. CMOS technology is used for constructing integrated circuit (IC) chips, including microprocessors, microcontrollers, memory chips (including Nonvolatile BIOS memory, CMOS BIOS), and other digital logic circuits. CMOS technology is also used for analog circuits such as image sensors (CMOS sensors), data conversion, data converters, RF circuits (RF CMOS), and highly integrated transceivers for many types of communication. In 1948, Bardeen and Brattain patented an insulated-gate transistor (IGFET) with an inversion layer. Bardeen's concept forms the basis of CMOS technology today. The CMOS process was presented by Fairchild Semico ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stereoscopy
Stereoscopy, also called stereoscopics or stereo imaging, is a technique for creating or enhancing the depth perception, illusion of depth in an image by means of stereopsis for binocular vision. The word ''stereoscopy'' derives . Any stereoscopic image is called a stereogram. Originally, stereogram referred to a pair of stereo images which could be viewed using a stereoscope. Most stereoscopic methods present a pair of two-dimensional images to the viewer. The left image is presented to the left eye and the right image is presented to the right eye. When viewed, the human brain perceives the images as a single 3D view, giving the viewer the perception of Three-dimensional space, 3D depth. However, the 3D effect lacks proper focal depth, which gives rise to the Vergence-accommodation conflict. Stereoscopy is distinguished from other types of 3d display#3D displays, 3D displays that display an image in Three-dimensional space, three full dimensions, allowing the observer to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Whole Sky Camera
A whole sky camera is a specialized camera used in meteorology and astronomy for capturing a photograph of the entire sky. Another application is that of hemispherical photography to study plant canopy geometry and to calculate near-ground solar radiation. Development Whole sky cameras typically use a fisheye lens that takes in an extremely wide, hemispherical image. Such lenses were originally developed for use in meteorology. However, alternative techniques are based on the photography of a mirror-like hemisphere which are more common. One of the first reported whole sky cameras was based on a series of pictures with lenses inclined to the horizon at an altitude of 45 degrees. With a lens that covers an angular field of 90 degrees, such camera revolves about a vertical axis. Meteorological applications In meteorological applications, whole sky cameras are used to study cloud cover, the current level of UV radiation, fractional cloud coverage, sky polarization, the computation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meniscus Lens
A lens is a transmissive optical device that focuses or disperses a light beam by means of refraction. A simple lens consists of a single piece of transparent material, while a compound lens consists of several simple lenses (''elements''), usually arranged along a common axis. Lenses are made from materials such as glass or plastic and are ground, polished, or molded to the required shape. A lens can focus light to form an image, unlike a prism, which refracts light without focusing. Devices that similarly focus or disperse waves and radiation other than visible light are also called "lenses", such as microwave lenses, electron lenses, acoustic lenses, or explosive lenses. Lenses are used in various imaging devices such as telescopes, binoculars, and cameras. They are also used as visual aids in glasses to correct defects of vision such as myopia and hypermetropia. History The word ''lens'' comes from , the Latin name of the lentil (a seed of a lentil plant), becau ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
R & J Beck
R & J Beck was an optical manufacturing enterprise established in 1843 by brothers Richard Beck (1827–1866) and Joseph Beck FRAS, FRMS (June 1828 – 18 April 1891). The firm operated from its headquarters located at 69 Mortimer Street in London. James Smith, worked with the company for a time, until his retirement in 1865. Smith's tenure is notably recognised for his instrumental role in elevating the significance of microscopes in scientific research circles. History Richard Beck (1827–1866) and Joseph Beck FRAS, FRMS (June 1828 – 18 April 1891) (nephews of J. J. Lister) formed the optical manufacturing firm of R and J Beck in 1843, based at 69 Mortimer Street, London. James Smith worked with the company under the name Smith and Beck, renamed Smith, Beck and Beck in 1854 but reverted to R and J Beck when Smith retired in 1865. Smith is credited with helping to raise the status of the use of microscopes within scientific research. Exhibitions and trades shows * 1851 G ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hill Sky Lens (1924)
A hill is a landform that extends above the surrounding terrain. It often has a distinct summit, and is usually applied to peaks which are above elevation compared to the relative landmass, though not as prominent as mountains. Hills fall under the category of slope landforms. Terminology The distinction between a hill and a mountain is unclear and largely subjective, but a hill is universally considered to be not as tall, or as steep as a mountain. Geographers historically regarded mountains as hills greater than above sea level. In contrast, hillwalkers have tended to regard mountains as peaks above sea level. The ''Oxford English Dictionary'' also suggests a limit of and Whittow states "Some authorities regard eminences above as mountains, those below being referred to as hills." Today, a mountain is usually defined in the UK and Ireland as any summit at least high, while the UK government's Countryside and Rights of Way Act 2000 defined mountainous areas (for the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromatic Aberration
In optics, chromatic aberration (CA), also called chromatic distortion, color aberration, color fringing, or purple fringing, is a failure of a lens to focus all colors to the same point. It is caused by dispersion: the refractive index of the lens elements varies with the wavelength of light. The refractive index of most transparent materials decreases with increasing wavelength. Since the focal length of a lens depends on the refractive index, this variation in refractive index affects focusing. Since the focal length of the lens varies with the color of the light different colors of light are brought to focus at different distances from the lens or with different levels of magnification. Chromatic aberration manifests itself as "fringes" of color along boundaries that separate dark and bright parts of the image. Types There are two types of chromatic aberration: ''axial'' (''longitudinal''), and ''transverse'' (''lateral''). Axial aberration occurs when different wavelengt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Horace Bénédict De Saussure
Horace Bénédict de Saussure (; 17 February 1740 – 22 January 1799) was a Genevan geologist, meteorologist, physicist, mountaineer and Alpine explorer, often called the founder of alpinism and modern meteorology, and considered to be the first person to build a successful solar oven. Early life and education Horace Bénédict de Saussure was born 17 February 1740, in Conches, near Geneva (''today in Switzerland but then an independent republic''). Saussure's family were Genevan patricians. His father, Nicolas de Saussure, was an agriculturist, agronomist and author. Because his mother was "sickly", Saussure was brought up by his mother's sister and her husband the Genevan naturalist Charles Bonnet, who sparked Horace-Bénédict's early interest in botany. After attending the "Collège" of his hometown, he completed his studies at the Geneva Academy in 1759 with a dissertation on heat (''Dissertatio physica de igne''). Career In 1760, Saussure made the first of nume ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peephole
A peephole, peekhole, spyhole, doorhole, magic eye, magic mirror or door viewer is a small, round opening through a door from which a viewer on the inside of a dwelling may "peek" to see directly outside the door. The lenses are made and arranged in such a way that viewing is only possible in one direction. The opening is typically no larger than the diameter of a Dime (United States coin), dime (). In a door, usually for apartments or hotel rooms, a peephole enables to see outside without opening the door nor revealing one's presence. Glass peepholes are often fitted with a fisheye lens to allow a wider field of view from the inside. ''Popular Science'', July 1950, p. 153, right-side. Preventing inside viewability Simple peepholes may allow people outside to see ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solar Radiation
Sunlight is the portion of the electromagnetic radiation which is emitted by the Sun (i.e. solar radiation) and received by the Earth, in particular the visible light perceptible to the human eye as well as invisible infrared (typically perceived by humans as warmth) and ultraviolet (which can have physiological effects such as sunburn) lights. However, according to the American Meteorological Society, there are "conflicting conventions as to whether all three ..are referred to as light, or whether that term should only be applied to the visible portion of the spectrum." Upon reaching the Earth, sunlight is scattered and filtered through the Earth's atmosphere as daylight when the Sun is above the horizon. When direct solar radiation is not blocked by clouds, it is experienced as sunshine, a combination of bright light and radiant heat (atmospheric). When blocked by clouds or reflected off other objects, sunlight is diffused. Sources estimate a global average o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
