News tagged with visible light
Chinese scientists create metamaterial black hole
(PhysOrg.com) -- Two physicists in China have used metamaterials to create the first artificial electromagnetic black hole. The scientists, Qiang Cheng and Tie Jun Cui from the Southeast University in Nanjing, ...
Oct 16, 2009 |
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Novel negative-index metamaterial that responds to visible light designed
A group of scientists led by researchers from the California Institute of Technology has engineered a type of artificial optical material—a metamaterial—with a particular three-dimensional structure such that ...
Apr 22, 2010 |
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A breakthrough in superlens development: Cheap, simple lens to let us see a single virus
A superlens would let you see a virus in a drop of blood and open the door to better and cheaper electronics. It might, says Durdu Guney, make ultra-high-resolution microscopes as commonplace as cameras in ...
Jan 09, 2012 |
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New 'broadband' cloaking technology simple to manufacture
(PhysOrg.com) -- Researchers have created a new type of invisibility cloak that is simpler than previous designs and works for all colors of the visible spectrum, making it possible to cloak larger objects ...
May 20, 2009 |
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Meta-flex: Your new brand for invisibility clothing
(PhysOrg.com) -- A team of physicists are one step closer to creating a Harry Potter-style invisibility cloak, with a new form of material that could also be attached to contact lenses to provide 'perfect' ...
Nov 03, 2010 |
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New nanolaser -- spaser -- key to future optical computers and technologies
(PhysOrg.com) -- Because the new device, called a "spaser," is the first of its kind to emit visible light, it represents a critical component for possible future technologies based on "nanophotonic" circuitry, ...
Aug 16, 2009 |
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New lens doubles the resolution of conventional microscopes
(PhysOrg.com) -- Conventional lenses can resolve structures around 200 nanometers (nm) in size, but scientists in Europe have for the first time developed a lens capable of achieving optical resolution of ...
Mar 25, 2011 |
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Discovery of an Unexpected Boost for Solar Water-Splitting Cells
(PhysOrg.com) -- A research team from Northeastern University and the National Institute of Standards and Technology has discovered, serendipitously, that a residue of a process used to build arrays of titania ...
Nanotechnology / Nanomaterials
Apr 22, 2009 |
5 / 5 (22) |
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Galaxy Cores to Crash in a Few Million Years
(PhysOrg.com) -- A new image from NASA's Spitzer Space Telescope offers a rare view of an imminent collision between the cores of two merging galaxies, each powered by a black hole with millions of times the ...
Mar 16, 2009 |
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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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The central region of the Milky Way
(PhysOrg.com) -- The center of our Milky Way galaxy is about 27,000 light-years away in the direction of the constellation of Sagittarius. At the very center of the galaxy lies a black hole whose mass is about ...
Aug 15, 2011 |
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Cantilever bends repeatedly under light exposure for continuous energy generation
(PhysOrg.com) -- With the goal to enable small electronic devices to harvest their own energy, researchers have designed a device that can convert light and thermal energy into electricity. When exposed to ...
Oct 05, 2010 |
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Transparent Carbon Nanotube Films Likely Successor to ITO for Commercial Applications
(PhysOrg.com) -- Will the legacy of Nobel prize winner Richard Smalley finally be fulfilled? Ever since his pioneering work in the mid 1990's on the synthesis of carbon nanotubes, companies have been struggling ...
Nanotechnology / Nanomaterials
Apr 10, 2009 |
4.4 / 5 (21) |
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Mantis shrimps could show us the way to a better DVD
(PhysOrg.com) -- The remarkable eyes of a marine crustacean could inspire the next generation of DVD and CD players, according to a new study from the University of Bristol published today in Nature Photonics.
Oct 25, 2009 |
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Berkeley Researchers Light Up White OLEDs
(PhysOrg.com) -- Light-emitting diodes, which employ semiconductors to produce artificial light, could reduce electricity consumption and lighten the impact of greenhouse gas emissions. However, moving this ...
Apr 06, 2010 |
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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.
