News tagged with visible spectrum
Metal oxides hold the key to cheap, green energy
Harnessing the energy of sunlight can be as simple as tuning the optical and electronic properties of metal oxides at the atomic level by making an artificial crystal or super-lattice 'sandwich' says a Binghamton ...
Nanotechnology / Nanomaterials
Apr 19, 2012 |
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Building a better light bulb
Scientists study the movement of charge carriers to design an organic LED that is energy efficient and still casts a warm, natural glow.
Feb 01, 2012 |
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Scientists solve mystery of colorful armchair nanotubes
(PhysOrg.com) -- Rice University researchers have figured out what gives armchair nanotubes their unique bright colors: hydrogen-like objects called excitons.
Nanotechnology / Nanomaterials
Jan 09, 2012 |
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Revolutionary new camera reveals the dark side of the Universe
(PhysOrg.com) -- A new camera that will revolutionise the field of submillimetre astronomy has been unveiled on the James Clerk Maxwell Telescope (JCMT) in Hawaii SCUBA-2 is far more sensitive and powerful ...
Dec 06, 2011 |
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Scientists use laser imaging to assess safety of zinc oxide nanoparticles in sunscreen
Ultra-tiny zinc oxide (ZnO) particles with dimensions less than one-ten-millionth of a meter are among the ingredients list of some commercially available sunscreen products, raising concerns about whether ...
Nanotechnology / Bio & Medicine
Nov 30, 2011 |
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Researchers change the color and shape of a single photon
(PhysOrg.com) -- A team of researchers from the CNST and ITL has simultaneously changed the color and shape of a single photon, the smallest unit of light.
Oct 06, 2011 |
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Saturn's geyser moon Enceladus shows off for Cassini
(PhysOrg.com) -- NASA's Cassini spacecraft successfully completed its Oct. 1 flyby of Saturn's moon Enceladus and its jets of water vapor and ice. At its closest approach, the spacecraft flew approximately ...
Space & Earth / Space Exploration
Oct 04, 2011 |
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Seeing beneath the soil to uncover the past
Archaeology is no longer just about digging holes. New research by a team led from the University of Leeds promises to improve the investigation of our heritage from the air.
Other Sciences / Archaeology & Fossils
Sep 13, 2011 |
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Hiding objects with a terahertz invisibility cloak
Researchers at Northwestern University have created a new kind of cloaking material that can render objects invisible in the terahertz range.
Sep 02, 2011 |
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Tunable nano-suspensions for light harvesting
A Syracuse University researcher has developed a patent-pending robust process to manufacture stable suspensions of metal nanoparticles capable of capturing sunlight.
Aug 22, 2011 |
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Nano-LEDs emit full visible spectrum of light
(PhysOrg.com) -- Physicists from Taiwan have designed and fabricated nano-sized light-emitting diodes (LEDs) that emit light spanning the entire visible spectrum. Although the tiny full-color LEDs aren't intended ...
Jun 17, 2011 |
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Invisibility carpet cloak can hide objects from visible light
(PhysOrg.com) -- Most of the invisibility cloaks that have been demonstrated to date conceal objects at frequencies that are not detectable by the human eye. Designing invisibility cloaks that can conceal ...
Jun 15, 2011 |
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Clouds' effect on sunlight energy at Earth's surface depends on the wavelength of light
Bouncing around from cloud to cloud, and down to Earth, sunlight's warmth is both enhanced and blocked by clouds. Atmospheric scientists from Pacific Northwest National Laboratory found that clouds' overall ...
Space & Earth / Earth Sciences
May 09, 2011 |
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Researchers create terahertz invisibility cloak
Researchers at Northwestern University have created a new kind of cloaking material that can render objects invisible in the terahertz range.
Apr 27, 2011 |
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Trapping a rainbow: Researchers slow broadband light waves with nanoplasmonic structures
A team of electrical engineers and chemists at Lehigh University have experimentally verified the "rainbow" trapping effect, demonstrating that plasmonic structures can slow down light waves over a broad range of wavelengths.
Mar 14, 2011 |
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Visible spectrum
The visible spectrum is the portion of the electromagnetic spectrum that is visible to (can be detected by) the human eye. Electromagnetic radiation in this range of wavelengths is called visible light or simply light. A typical human eye will respond to wavelengths from about 380 to 750 nm. In terms of frequency, this corresponds to a band in the vicinity of 790–400 terahertz. A light-adapted eye generally has its maximum sensitivity at around 555 nm (540 THz), in the green region of the optical spectrum (see: luminosity function). The spectrum does not, however, contain all the colors that the human eyes and brain can distinguish. Unsaturated colors such as pink, and purple colors such as magenta are absent, for example, because they can only be made by a mix of multiple wavelengths.
Visible wavelengths also pass through the "optical window," the region of the electromagnetic spectrum that passes largely unattenuated through the Earth's atmosphere. (Blue light scatters more than red light, which is why the sky appears blue.) The human eye's response is defined by subjective testing (see CIE), but atmospheric windows are defined by physical measurement.
The "visible window" is so called because it overlaps the human visible response spectrum. The near infrared (NIR) windows lie just out of human response window, and the Medium Wavelength IR (MWIR) and Long Wavelength or Far Infrared (LWIR or FIR) are far beyond the human response region.
Many species can see wavelengths that fall outside the "visible spectrum". Bees and many other insects can see light in the ultraviolet, which helps them find nectar in flowers. Plant species that depend on insect pollination may owe reproductive success to their appearance in ultraviolet light, rather than how colorful they appear to us. Birds too can see into the ultraviolet (300-400 nm), and some have sex-dependent markings on their plumage, which are only visible in the ultraviolet range.
For more information about Visible spectrum, read the full article at
Wikipedia.
This text uses material from Wikipedia and is available under the GNU Free Documentation License.
