Japanese researchers said Thursday they have developed a human-shaped mobile phone with a skin-like outer layer that enables users to feel closer to those on the other end.
Hi Tech & Innovation
Mar 3, 2011
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More luminous and energy efficient than LEDs, white lasers look to be the future in lighting and light-based wireless communication.
Optics & Photonics
Jul 29, 2015
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(PhysOrg.com) -- One of the most difficult problems for designing mobile devices is finding a way to minimize the size of the device while simultaneously maximizing the size of the display. To get the best of both worlds, ...
(PhysOrg.com) -- Engineers at the University of California, Los Angeles, have created the first fully stretchable organic light-emitting diode (OLED). The researchers devised a way of creating a carbon nanotube and polymer ...
(PhysOrg.com) -- Light bulbs that last 100 years and fill rooms with brilliant ambiance may become a reality sooner rather than later, thanks to a National Renewable Energy Laboratory discovery.
Engineering
Apr 5, 2010
20
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(PhysOrg.com) -- Researchers from France, Italy and the United States are weaving cotton with transistors for a new look in computing. Based on news about a lab at Cornell University, wearable computing is getting a new twist. ...
Light-emitting diodes (LEDs) have revolutionized modern lighting and sensing technology. From applications in our homes to industry, LEDs are used for all lighting applications, from indoor lighting over TV screens to biomedicine. ...
Optics & Photonics
Jan 9, 2024
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(PhysOrg.com) -- Sony is showing off prototypes incorporating its super-thin, flexible OLED technology at the CREATEC JAPAN 2009 IT and electronics trade show in Makuhari Messe (Chiba) in Japan.
Solid-state lighting based on light-emitting diodes (LEDs) is the most efficient source of high color quality white light. Nevertheless, they show significant performance limitations such as the "efficiency droop". Blue laser ...
Optics & Photonics
Nov 11, 2013
0
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A groundbreaking report recently released by the American Medical Association (AMA) Council on Science and Public Health affirms known and suspected impacts to human health and the environment caused by light emitting diodes ...
Environment
Jun 22, 2016
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A light-emitting diode (LED) (pronounced /ˌɛliːˈdiː/, or just /lɛd/), is an electronic light source. The LED was first invented in Russia in the 1920s, and introduced in America as a practical electronic component in 1962. Oleg Vladimirovich Losev was a radio technician who noticed that diodes used in radio receivers emitted light when current was passed through them. In 1927, he published details in a Russian journal of the first ever LED.
All early devices emitted low-intensity red light, but modern LEDs are available across the visible, ultraviolet and infra red wavelengths, with very high brightness.
LEDs are based on the semiconductor diode. When the diode is forward biased (switched on), electrons are able to recombine with holes and energy is released in the form of light. This effect is called electroluminescence and the color of the light is determined by the energy gap of the semiconductor. The LED is usually small in area (less than 1 mm2) with integrated optical components to shape its radiation pattern and assist in reflection.
LEDs present many advantages over traditional light sources including lower energy consumption, longer lifetime, improved robustness, smaller size and faster switching. However, they are relatively expensive and require more precise current and heat management than traditional light sources.
Applications of LEDs are diverse. They are used as low-energy indicators but also for replacements for traditional light sources in general lighting and automotive lighting. The compact size of LEDs has allowed new text and video displays and sensors to be developed, while their high switching rates are useful in communications technology.
This text uses material from Wikipedia, licensed under CC BY-SA
