University of Illinois at Chicago
The University of Illinois at Chicago is a public research university in Chicago, Illinois. Its campus is in the Near West Side community area, adjacent to the Chicago Loop; the second campus established under the University of Illinois system, UIC is the largest university in the Chicago area, having 30,000 students enrolled in 15 colleges. UIC operates the largest medical school in the United States with research expenditures exceeding $412 million and ranks in the top 50 U. S. institutions for research expenditures. In the 2015 U. S. News & World Report's ranking of colleges and universities, UIC ranked as the 129th best in the "national universities" category; the 2015 Times Higher Education World University Rankings ranked UIC as the 18th best in the world among universities less than 50 years old. UIC competes in NCAA Division I Horizon League as the UIC Flames in sports; the UIC Pavilion is home to all UIC basketball games. It serves as a venue for concerts; the University of Illinois at Chicago traces its origins to several private health colleges founded during the late 19th century, including the Chicago College of Pharmacy, which opened in 1859, the College of Physicians and Surgeons, the Columbian College of Dentistry.
The University of Illinois was chartered in 1867 in Champaign-Urbana, as the state's land-grant university. In exchange for agreeing to the Champaign-Urbana location, Chicago-area legislators were promised that a "polytechnical" branch would open in Chicago; the Chicago-based health colleges affiliated with the University in 1896–97, becoming incorporated into the University of Illinois in 1913, as the Colleges of Medicine and Pharmacy. Medical education and research expanded in the succeeding decades, leading to the development of several other health science colleges, which were brought together as the Chicago Professional Colleges. In 1935, the first act of newly elected state representative Richard J. Daley was to introduce a resolution calling for the establishment of an undergraduate Chicago campus of the University of Illinois; as World War II was drawing to a close, Congress passed the G. I. Bill in 1944, which sought to reward veterans for their military service. Among other benefits, it provided educational funding, making college degrees far more attainable to the American public.
In 1945, a state senator, introduced four bills calling for a university in Chicago. In 1946, realizing that they would be "besieged with applications", University of Illinois officials opened what was to be a temporary branch campus called the Chicago Undergraduate Division on Navy Pier; the campus was not a junior college, but rather had a curriculum based on Urbana's courses, students who completed the first two years' requirements could go on to Urbana and finish their degree. Classes at the CUD campus began in October 1946, 4,000 students enrolled each semester. Nicknamed "Harvard on the rocks", three-quarters of its students were veterans on the G. I. Bill, many of whom were immigrants and most of whom worked other part-time jobs to support themselves, it accommodated first-generation college students from working families who commuted from home. Demand for a public university education in Chicago remained high, the University made plans to create a permanent degree-granting campus in the Chicago area.
Indeed, because it was a two-year school, students at the University of Illinois at Navy Pier needed to transfer to a higher-tuition private college in Chicago or go to the main campus in Champaign-Urbana, where there were fewer job opportunities. Daley succeeded in getting the state senate in 1951 to pass a bill calling for a Chicago campus. Daley became mayor of Chicago in 1955 and pressed the University of Illinois to upgrade the Chicago Undergraduate Center to a full-fledged four-year institution. After a long and controversial site decision process, in 1961, Mayor Daley offered the Harrison and Halsted Streets site for the new campus. In December 1961, the final decision to establish a four-year university in Chicago was made. In that same year, the Chicago Professional Colleges became the University of Illinois at the Medical Center. In 1963, construction began on the University's new Chicago campus at Halsted Streets. In February 1965, the new Chicago campus opened and was named the University of Illinois at Congress Circle referencing the Circle Interchange of I-290 and I-90/I-94).
Shortly before opening, the Congress expressway was renamed the Eisenhower Expressway and the campus was renamed to University of Illinois at Chicago Circle. UICC was designed in the brutalist style by Walter Netsch of Skidmore and Merrill, a Chicago-based architectural firm responsible for many of today's tallest skyscrapers. Unlike the CUD campus, Circle was a degree-granting institution. Within five years of the campus' opening, in addition to undergraduate degrees every department offered graduate degrees. In September 1982, the University of Illinois system consolidated UICC and UIMC to form the University of Illinois at Chicago. In 2000, UIC began developing the South Campus; the expansion of UIC south of Roosevelt Road increased on-campus living space and research facilities. One in ten Chicagoans with a college degree is a UIC alumnus. One in eight Illinois doctors is a graduate of the UIC College of Medicine. One in three Illinois pharmacists is a graduate of the College of Pharmacy. Half of all the dentists in Illinois are graduates of UIC's College of Dentistry.
The University of Illi
Immersion (virtual reality)
Immersion into virtual reality is a perception of being physically present in a non-physical world. The perception is created by surrounding the user of the VR system in images, sound or other stimuli that provide an engrossing total environment; the name is a metaphoric use of the experience of submersion applied to representation, fiction or simulation. Immersion can be defined as the state of consciousness where a "visitor" or "immersant"'s awareness of physical self is transformed by being surrounded in an artificial environment; the degree to which the virtual or artistic environment faithfully reproduces reality determines the degree of suspension of disbelief. The greater the suspension of disbelief, the greater the degree of presence achieved. According to Ernest W. Adams and consultant on game design, immersion can be separated into three main categories: Tactical immersion Tactical immersion is experienced when performing tactile operations that involve skill. Players feel "in the zone".
Strategic immersion Strategic immersion is more cerebral, is associated with mental challenge. Chess players experience strategic immersion when choosing a correct solution among a broad array of possibilities. Narrative immersion Narrative immersion occurs when players become invested in a story, is similar to what is experienced while reading a book or watching a movie. Staffan Björk and Jussi Holopainen, in Patterns In Game Design, divide immersion into similar categories, but call them sensory-motoric immersion, cognitive immersion and emotional immersion, respectively. In addition to these, they add a new category: Spatial immersion Spatial immersion occurs when a player feels the simulated world is perceptually convincing; the player feels that he or she is "there" and that a simulated world looks and feels "real". Presence, a term derived from the shortening of the original "telepresence", is a phenomenon enabling people to interact with and feel connected to the world outside their physical bodies via technology.
It is defined as a person's subjective sensation of being there in a scene depicted by a medium virtual in nature. Most designers focus on the technology used to create a high-fidelity virtual environment, it is the subjective perception, although generated by and/or filtered through human-made technology, that determines the successful attainment of presence. Virtual reality glasses can produce a visceral feeling of being in a simulated world, a form of spatial immersion called Presence. According to Oculus VR, the technology requirements to achieve this visceral reaction are low-latency and precise tracking of movements. Michael Abrash gave a talk on VR at Steam Dev Days in 2014. According to the VR research team at Valve, all of the following are needed to establish presence. A wide field of view Adequate resolution Low pixel persistence A high enough refresh rate Global display where all pixels are illuminated Optics Optical calibration Rock-solid tracking – translation with millimeter accuracy or better, orientation with quarter degree accuracy or better, volume of 1.5 meter or more on a side Low latency Immersive virtual reality is a hypothetical future technology that exists today as virtual reality art projects, for the most part.
It consists of immersion in an artificial environment where the user feels just as immersed as they feel in consensus reality. The most considered method would be to induce the sensations that made up the virtual reality in the nervous system directly. In functionalism/conventional biology we interact with consensus reality through the nervous system, thus we receive all input from all the senses as nerve impulses. It gives your neurons a feeling of heightened sensation, it would involve the user receiving inputs as artificially stimulated nerve impulses, the system would receive the CNS outputs and process them allowing the user to interact with the virtual reality. Natural impulses between the body and central nervous system would need to be prevented; this could be done by blocking out natural impulses using nanorobots which attach themselves to the brain wiring, whilst receiving the digital impulses of which describe the virtual world, which could be sent into the wiring of the brain. A feedback system between the user and the computer which stores the information would be needed.
Considering how much information would be required for such a system, it is that it would be based on hypothetical forms of computer technology. Understanding of the nervous systemA comprehensive understanding of which nerve impulses correspond to which sensations, which motor impulses correspond to which muscle contractions will be required; this will allow the correct sensations in the user, actions in the virtual reality to occur. The Blue Brain Project is the current, most promising research with the idea of understanding how the brain works by building large scale computer models. Ability to manipulate CNSThe nervous system would need to be manipulated. Whilst non-invasive devices using radiation have been postulated, invasive cybernetic implants are to become available sooner an
Daniel J. Sandin
Daniel J. Sandin is an American video and computer graphics artist and researcher, he is a Professor Emeritus of the School of Art & Design at University of Illinois at Chicago, co-director of the Electronic Visualization Laboratory at the University of Illinois at Chicago. He is an internationally recognized pioneer in electronic art and visualization. Dan Sandin received his B. A. in Natural Sciences from Shimer College in 1964 and his M. S. in Physics from the University of Wisconsin–Madison in 1967. He became interested in video in 1967, while helping to organize student demonstrations at the University of Illinois. In 1969, he joined as a teacher at the University of Illinois at Chicago, in order to bring technology into the arts program; this was shortly after his presentation of "Glowflow", a computer controlled light and sound system, created with Myron Krueger, Jerry Erdman, Richard Venezky. By 1972, Thomas A. DeFanti joined UIC and together with Sandin they founded the Circle Graphics Habitat, now known as the Electronic Visualization Laboratory.
His major achievements were working on a series of projects including: Glowflow, Sandin Image Processor, Sayre Glove, PHSColograms, CAVE and ImmersaDesk and Infinity Wall. Dan Sandin received several awards including: the Guggenheim Fellowships awarded for video and sound in 1978, the National Endowment for the Arts for video art in 1981, the Rockefeller Foundation's Video Fellowship in 1981, the Inventor of the Year award from the University of Illinois in 2000, the Rockefeller Foundation's Film and Multimedia Fellowship in 2002 for "Looking for Water 2," a virtual-reality, 3-D installation. Dan Sandin has said that his career has three main objectives: the design of electronic instruments and computer programs for visual performance and personal growth. From 1971 to 1973, he designed the Sandin Image Processor, a patch programmable analog computer for real-time manipulation of video inputs through the control of the grey level information, his friend and neighbor Phil Morton helped with the early schematic plans diagram.
This modular design was based on the Moog synthesizer. With Tom DeFanti, he would combine it with real-time computer graphics and synthesized music and perform visual concerts, he has performed worldwide and has received grants in support of his work from the Rockefeller Foundation, the National Science Foundation, the National Endowment for the Arts and the Guggenheim Foundation. His piece "Spiral PTL" was one of the first pieces included in the Museum of Modern Art's video art collection. In 1977, with Tom DeFanti and Rich Sayre, he designed the Sayre Glove, the first data glove, as part of a grant from the National Endowment for the Arts; this device used light based sensors with flexible tubes with a light source at one end and a photocell at the other. As the fingers were bent, the amount of light that hit the photocells varied, thus providing a measure of finger flexion, it was used to manipulate sliders, but was lightweight and inexpensive. By 1988, Sandin was working on a type of digital photography called PHSColograms.
The effect was similar to holograms and many times viewers would mistake them as such. The initial system supported 13 images but further improvements now could allow 100 such images to be used; this system was designed for use in the medical field where these quasi-3D images could benefit surgeons. The first CAVE was invented by Carolina Cruz-Neira, Daniel J. Sandin, Thomas A. DeFanti in 1992; this is an immersive system that became the standard for rear projection-based Virtual Reality systems. The normal full system consists of projections screens along the front and floor axes, a tracking system for the "user". Although they used the recursive acronym Cave Automatic Virtual Environment for the CAVE system, the name refers to Plato's "Republic" and "The Allegory of the Cave" where he explored the concepts of reality and human perception. Since there have been a couple offshoots of the CAVE technology, including ImmersaDesk, Infinity Wall and Oblong Industries' G-speak system; the ImmersaDesk is a semi-immersive system, resembling a drafting table, while the Infinity Wall is designed to cater to an entire room of people, such as a conference room.
Extending this concept, G-speak supports gestural input from multiple-users and multiple-devices on and expandable array of monitors. Daniel Sandin @ EVL n web site Daniel Sandin in the Video Data Bank Daniel Sandin at the Media Burn Independent Video Archive
SIGGRAPH is the annual conference on computer graphics convened by the ACM SIGGRAPH organization. The first SIGGRAPH conference was in 1974; the conference is attended by tens of thousands of computer professionals. Past conferences have been held in Los Angeles, New Orleans, Boston and elsewhere in North America. SIGGRAPH Asia, a second yearly conference, has been held since 2008 in various Asian countries; the strength of SIGGRAPH comes from the chapters set all around the world. Some highlights of the conference are its Animation Theater and Electronic Theater presentations, where created CG films are played. There is a large exhibition floor, where several hundred companies set up elaborate booths and compete for attention and recruits. Most of the companies are in the engineering, motion picture, or video game industries. There are many booths for schools which specialize in computer graphics or interactivity. Dozens of research papers are presented each year, SIGGRAPH is considered the most prestigious forum for the publication of computer graphics research.
The recent paper acceptance rate for SIGGRAPH has been less than 26%. The submitted papers are peer-reviewed in a single-blind process. There has been some criticism about the preference of SIGGRAPH paper reviewers for novel results rather than useful incremental progress; the papers accepted for presentation at SIGGRAPH are printed since 2003 in a special issue of the ACM Transactions on Graphics journal. Prior to 1992, SIGGRAPH papers were printed as part of the Computer Graphics publication. In addition to the papers, there are numerous panels of industry experts set up to discuss a wide variety of topics, from computer graphics to machine interactivity to education. SIGGRAPH offers many full- and half-day courses in state-of-the-art computer graphics topics, as well as shorter "sketch" presentations where artists and researchers discuss their latest work. In 1984, under LucasFilm Computer Group, John Lasseter's first computer animated short, The Adventures of André & Wally B. premiered at SIGGRAPH.
Pixar's first computer animated short, Luxo, Jr. debuted in 1986. Pixar has debuted numerous shorts at the conference since. SIGGRAPH has several awards programs to recognize outstanding contributions to computer graphics; the most prestigious is the Steven Anson Coons Award for Outstanding Creative Contributions to Computer Graphics. It has been awarded every two years since 1983 to recognize an individual's lifetime achievement in computer graphics; the following conference areas are the areas scheduled for SIGGRAPH 2012, as some conference areas vary annually. ACM Student Research Competition Art Gallery: presents digital and technologically mediated artworks Art Papers: features the artists and artwork, processes and theoretical frameworks for making art and contextualizing its place in society Birds of a Feather: informal presentations and demonstrations Computer Animation Festival: an annual festival for the world's most innovative and amazing digital film and video creators Courses: Attendees learn from the experts in the field and gain inside knowledge, critical to career advancement.
Emerging Technologies: presents innovative technologies and applications in several fields, from displays and input devices to collaborative environments and robotics, technologies that apply to film and game production Exhibition: presents the newest hardware systems, software tools, creative services from hundreds of companies International Resources: Focusing on the state of computer graphics in different regions of the world, it offers bilingual tours of conference programs, informal translation services, space for meetings and demonstrations. Job Fair: a place for employers to meet with thousands of job seekers Keynote Speakers: stories from the most influential practitioners in computer graphics, interactive techniques, related fields Panels: moderated discussions on important topics, with expert panelists chosen by the organizers to provide a wide range of perspectives Posters: presenting student, in-progress, late-breaking work Real-Time Live!: showcase for the latest trends and techniques for pushing the boundaries of interactive visuals Sandbox: provides an opportunity to get hands-on with the latest, most innovative real-time projects produced over the last 12 months SIGkids: engages local youngsters with outreach and on-site programs to excite and cultivate the next-next-generation SIGGRAPH Business Symposium SIGGRAPH Dailies: Each presenter has one minute to present an animation and describe the work.
Studio: a place for making and creating at SIGGRAPH Talks: presentations on recent achievements in all areas of computer graphics and interactive techniques, including art, animation, visual effects, interactivity and engineering Technical Papers: the premier international forum for disseminating new scholarly work in computer graphics and interactive techniques Technical Papers Fast Forward: summary of Technical Papers. SIGGRAPH Mobile: focusing on mobile computer graphics and its applications such as augmented reality and interactive apps. At SIGGRAPH ASIA this track is called Symposium of Apps. Association for Computing Machinery ACM SIGGRAPH ACM Transactions on Graphics Computer Graphics, a publication of ACM SIGGRAPH The list of computer science conferences contains other academic conferences in computer science. ACM SIGGRAPH website ACM SIGGRAPH conference publications ACM SIGGRAPH YouTube SIGGRAPH 2017 Conference, Los Angeles, CA SIGGRAPH Asia 2017 Conference, Thai
Allegory of the Cave
The Allegory of the Cave, or Plato's Cave, was presented by the Greek philosopher Plato in his work Republic to compare "the effect of education and the lack of it on our nature". It is written as a dialogue between Plato's brother Glaucon and his mentor Socrates, narrated by the latter; the allegory is presented after the analogy of the divided line. All three are characterized in relation to dialectic at the end of Books VII and VIII. Plato has Socrates describe a group of people who have lived chained to the wall of a cave all of their lives, facing a blank wall; the people watch shadows projected on the wall from objects passing in front of a fire behind them, give names to these shadows. The shadows are the prisoners' reality. Socrates explains how the philosopher is like a prisoner, freed from the cave and comes to understand that the shadows on the wall are not reality at all, for he can perceive the true form of reality rather than the manufactured reality, the shadows seen by the prisoners.
The inmates of this place do not desire to leave their prison, for they know no better life. The prisoners manage to break their bonds one day, discover that their reality was not what they thought it was, they discovered the sun. Like the fire that cast light on the walls of the cave, the human condition is forever bound to the impressions that are received through the senses. If these interpretations are an absurd misrepresentation of reality, we cannot somehow break free from the bonds of our human condition—we cannot free ourselves from phenomenal state just as the prisoners could not free themselves from their chains. If, however, we were to miraculously escape our bondage, we would find a world that we could not understand—the sun is incomprehensible for someone who has never seen it. In other words, we would encounter another "realm", a place incomprehensible because, theoretically, it is the source of a higher reality than the one we have always known. Socrates remarks that this allegory can be paired with previous writings, namely the analogy of the sun and the analogy of the divided line.
The allegory of the cave is called the analogy of the cave, myth of the cave, metaphor of the cave, parable of the cave, Plato's Cave. Plato begins by having Socrates ask Glaucon to imagine a cave where people have been imprisoned from birth; these prisoners are chained so that their legs and necks are fixed, forcing them to gaze at the wall in front of them and not look around at the cave, each other, or themselves. Behind the prisoners is a fire, between the fire and the prisoners is a raised walkway with a low wall, behind which people walk carrying objects or puppets "of men and other living things"; the people walk behind the wall so their bodies do not cast shadows for the prisoners to see, but the objects they carry do. The prisoners cannot see any of what is happening behind them, they are only able to see the shadows cast upon the cave wall in front of them; the sounds of the people talking echo off the walls, the prisoners believe these sounds come from the shadows. Socrates suggests that the shadows are reality for the prisoners because they have never seen anything else.
The fire, or human made light, the puppets, used to make shadows, are done by the artists. This can be compared to how illusions are made with light and sound today, with electronics, movies, 3D visuals. Plato, indicates that the fire is the political doctrine, taught in a nation state; the artists use light and shadows to teach the dominant doctrines of a place. Few humans will escape the cave; this is not some easy task, only a true philosopher, with decades of preparation, would be able to leave the cave, up the steep incline. Most humans will live at the bottom of the cave, a small few will be the major artists that project the shadows with the use of human made light. Plato supposes that one prisoner is freed; this prisoner would see the fire. The light would make it difficult for him to see the objects casting the shadows. If he were told that what he is seeing is real instead of the other version of reality he sees on the wall, he would not believe it. In his pain, Plato continues, the freed prisoner would turn away and run back to what he is accustomed to.
He writes "... it would hurt his eyes, he would escape by turning away to the things which he was able to look at, these he would believe to be clearer than what was being shown to him."Plato continues: "Suppose... that someone should drag him... by force, up the rough ascent, the steep way up, never stop until he could drag him out into the light of the sun." The prisoner would be angry and in pain, this would only worsen when the radiant light of the sun overwhelms his eyes and blinds him."Slowly, his eyes adjust to the light of the sun. First he can only see shadows, he can see the reflections of people and things in water and later see the people and things themselves. He is able to look at the stars and moon at night until he can look upon the sun itself." Only after he can look straight at the sun "is he able to reason about it" and what it is. (See Plat
Electronic Visualization Laboratory
The Electronic Visualization Laboratory is a cross-disciplinary research lab at the University of Illinois at Chicago. It brings together faculty and students from the Art and Computer Science departments of UIC; the primary areas of research are in computer graphics, high-performance computer networking, technological art. EVL represents one of the oldest art and engineering collaborations in the United States, it was founded in 1973 by Dan Sandin. The lab was known as the Circle Graphics Habitat, in reference to the then-name of UIC, the University of Illinois at Chicago Circle. DeFanti and Sandin have served as Co-Directors of the lab since its founding. In 1987, they were joined by Maxine D. Brown as Associate Director. Work at EVL over the years has included: 1977: the first dataglove. 1981: The Z Box hardware and ZGRASS software, an early graphics system for the Bally home computer. This system featured NTSC video output and was used by a number of computer graphics artists of the time. 1988: Computer generated PHSColograms, an autostereoscopic 3D technique, with n. 1992: The CAVE Automatic Virtual Environment, a projection-based virtual reality system.
1995: The I-WAY event at Supercomputing'95, a prototype of grid computing. 1997: The STAR TAP project, a linking up of several international high-performance networks. Followed by the StarLight optical networking facility. 2013: SpiderSense, a pioneer project in the field of human augmentics. SpiderSense is a wearable device that integrates ultrasound technology with vibrating hardware, allowing users to have directional awareness and "sense" obstacles in the environment without physically seeing the obstacles. Highlights of the electronic art work done at EVL include: Electronic Visualization Events in the mid 1970s - live, real-time performances featuring computer graphics, video processing, music. Early computer graphics art videos, created by combining DeFanti's GRASS system on a PDP-11 and the Sandin Image Processor; the video Spiral PTL was included in the inaugural collection of video art at the Museum of Modern Art. Computer artist Larry Cuba spent time at EVL, using the tools there for his films 3/78 and Calculated Movements, as well as a short special effects sequence for Star Wars.
In 1996, EVL installed the first publicly accessible CAVE at the Ars Electronica Center in Austria, presented a number of virtual reality artworks. The members of EVL have been involved with the SIGGRAPH organization and conference since its inception. DeFanti has served as Secretary and Chair of the organization, 1979 conference chair. Brown has served as Vice Chair for Operations and Secretary, chaired the 1992 conference. According to Jim Blinn, the popular Electronic Theatre "started out as a bunch of people crowding into Dan Sandin’s dorm room to watch videotapes." In 1979, DeFanti established the SIGGRAPH Video Review. At SIGGRAPH'92, EVL organized the "Showcase" event, where researchers demonstrated 35 projects in state-of-the-art computational science and scientific visualization. At SIGGRAPH'94, EVL organized the VROOM event, demonstrations of the state of virtual reality technology. In 1998, Brown received the first SIGGRAPH Outstanding Service Award for her contributions to the organization.
In 2000, DeFanti and EVL alumna Copper Giloth received the Outstanding Service Award. EVL Website STAR TAP / STARLIGHT
Infrared radiation, sometimes called infrared light, is electromagnetic radiation with longer wavelengths than those of visible light, is therefore invisible to the human eye, although IR at wavelengths up to 1050 nanometers s from specially pulsed lasers can be seen by humans under certain conditions. IR wavelengths extend from the nominal red edge of the visible spectrum at 700 nanometers, to 1 millimeter. Most of the thermal radiation emitted by objects near room temperature is infrared; as with all EMR, IR carries radiant energy and behaves both like a wave and like its quantum particle, the photon. Infrared radiation was discovered in 1800 by astronomer Sir William Herschel, who discovered a type of invisible radiation in the spectrum lower in energy than red light, by means of its effect on a thermometer. More than half of the total energy from the Sun was found to arrive on Earth in the form of infrared; the balance between absorbed and emitted infrared radiation has a critical effect on Earth's climate.
Infrared radiation is emitted or absorbed by molecules when they change their rotational-vibrational movements. It excites vibrational modes in a molecule through a change in the dipole moment, making it a useful frequency range for study of these energy states for molecules of the proper symmetry. Infrared spectroscopy examines transmission of photons in the infrared range. Infrared radiation is used in industrial, military, law enforcement, medical applications. Night-vision devices using active near-infrared illumination allow people or animals to be observed without the observer being detected. Infrared astronomy uses sensor-equipped telescopes to penetrate dusty regions of space such as molecular clouds, detect objects such as planets, to view red-shifted objects from the early days of the universe. Infrared thermal-imaging cameras are used to detect heat loss in insulated systems, to observe changing blood flow in the skin, to detect overheating of electrical apparatus. Extensive uses for military and civilian applications include target acquisition, night vision and tracking.
Humans at normal body temperature radiate chiefly at wavelengths around 10 μm. Non-military uses include thermal efficiency analysis, environmental monitoring, industrial facility inspections, detection of grow-ops, remote temperature sensing, short-range wireless communication and weather forecasting. Infrared radiation extends from the nominal red edge of the visible spectrum at 700 nanometers to 1 millimeter; this range of wavelengths corresponds to a frequency range of 430 THz down to 300 GHz. Below infrared is the microwave portion of the electromagnetic spectrum. Sunlight, at an effective temperature of 5,780 kelvins, is composed of near-thermal-spectrum radiation, more than half infrared. At zenith, sunlight provides an irradiance of just over 1 kilowatt per square meter at sea level. Of this energy, 527 watts is infrared radiation, 445 watts is visible light, 32 watts is ultraviolet radiation. Nearly all the infrared radiation in sunlight is shorter than 4 micrometers. On the surface of Earth, at far lower temperatures than the surface of the Sun, some thermal radiation consists of infrared in the mid-infrared region, much longer than in sunlight.
However, black body or thermal radiation is continuous: it gives off radiation at all wavelengths. Of these natural thermal radiation processes, only lightning and natural fires are hot enough to produce much visible energy, fires produce far more infrared than visible-light energy. In general, objects emit infrared radiation across a spectrum of wavelengths, but sometimes only a limited region of the spectrum is of interest because sensors collect radiation only within a specific bandwidth. Thermal infrared radiation has a maximum emission wavelength, inversely proportional to the absolute temperature of object, in accordance with Wien's displacement law. Therefore, the infrared band is subdivided into smaller sections. A used sub-division scheme is: NIR and SWIR is sometimes called "reflected infrared", whereas MWIR and LWIR is sometimes referred to as "thermal infrared". Due to the nature of the blackbody radiation curves, typical "hot" objects, such as exhaust pipes appear brighter in the MW compared to the same object viewed in the LW.
The International Commission on Illumination recommended the division of infrared radiation into the following three bands: ISO 20473 specifies the following scheme: Astronomers divide the infrared spectrum as follows: These divisions are not precise and can vary depending on the publication. The three regions are used for observation of different temperature ranges, hence different environments in space; the most common photometric system used in astronomy allocates capital letters to different spectral regions according to filters used. These letters are understood in reference to atmospheric windows and appear, for instance, in the titles of many papers. A third scheme divides up the band based on the response of various detectors: Near-infrared: from 0.7 to 1.0 µm. Short-wave infrared: 1.0 to 3 µm. InGaAs covers to about 1.8 µm. Mid-wave infrared: 3 to 5 µm (defined by the atmospheric window and covered by indium antimonide and mercury cadmium telluride and by lead