Japan develops mobile phone with human touch

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.

UCLA engineers create fully stretchable OLED

(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 ...

Rebates to cut price of $60 LED bulb

(AP) -- How much would you pay for an amazing, state-of-the-art light bulb? Shoppers will be asking themselves that very question at Home Depot and other outlets starting Sunday - Earth Day - when the bulb that won a $10 ...

NREL Finds a Way to Give LEDs the Green Light

(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.

Cotton computing goes live at Cornell textiles lab

(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. ...

Super-thin flexible OLED from Sony

(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.

Laser diodes versus LEDs

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 ...

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Diode

In electronics, a diode is a two-terminal device (thermionic diodes may also have one or two ancillary terminals for a heater).

Diodes have two active electrodes between which the signal of interest may flow, and most are used for their unidirectional electric current property. The varicap diode is used as an electrically adjustable capacitor.

The unidirectionality most diodes exhibit is sometimes generically called the rectifying property. The most common function of a diode is to allow an electric current in one direction (called the forward biased condition) and to block the current in the opposite direction (the reverse biased condition). Thus, the diode can be thought of as an electronic version of a check valve.

Real diodes do not display such a perfect on-off directionality but have a more complex non-linear electrical characteristic, which depends on the particular type of diode technology. Diodes also have many other functions in which they are not designed to operate in this on-off manner.

Early diodes included “cat’s whisker” crystals and vacuum tube devices (also called thermionic valves). Today most diodes are made of silicon, but other semiconductors such a germanium are sometimes used.

This text uses material from Wikipedia, licensed under CC BY-SA