A light-emitting diode (LED) is a semiconductor light source that emits light when current flows through it. Electrons in the semiconductor recombine with electron holes, releasing energy in the form of photons. The color of the light is determined by the energy required for electrons to cross the band gap of the semiconductor. White light is obtained by using multiple semiconductors or a layer of light-emitting phosphor on the semiconductor device.
Direct current (DC) is the unidirectional flow of an electric charge. An electrochemical cell is a prime example of DC power. Direct current may flow through a conductor such as a wire, but can also flow through semiconductors, insulators, or even through a vacuum as in electron or ion beams. The electric current flows in a constant direction, distinguishing it from alternating current (AC). A term formerly used for this type of current was galvanic current.
Electroluminescence (EL) is an optical phenomenon and electrical phenomenon in which a material emits light in response to the passage of an electric current or to a strong electric field. This is distinct from black body light emission resulting from heat (incandescence), a chemical reaction (chemiluminescence), sound (sonoluminescence), or other mechanical action (mechanoluminescence).
A flashlight is a portable hand-held electric light. The source of the light is usually an incandescent light bulb (lamp) or light-emitting diode (LED). A typical flashlight consists of the light source mounted in a reflector, a transparent cover to protect the light source and reflector, a battery, and a switch. These are supported and protected by a case.
Bicycle lighting is illumination attached to bicycles whose purpose above all is, along with reflectors, to improve the visibility of the bicycle and its rider to other road users under circumstances of poor ambient illumination. A secondary purpose is to illuminate reflective materials such as cat's eyes and traffic signs. A third purpose may be to illuminate the roadway so that the rider can see the way ahead. Serving the latter purposes require much more luminous flux and thus more power.
The Nokia 3100 is a triband-GSM mobile phone announced on 17 June 2003 as an entry-level phone from Nokia and released in September 2003, designed primarily for the newer generation of marketing audience.
An emergency light is a battery-backed lighting device that switches on automatically when a building experiences a power outage. Emergency lights are standard in new commercial and high occupancy residential buildings, such as college dormitories, apartments, and hotels. Most building codes require that they be installed in older buildings as well.
A light fixture, light fitting, or luminaire is an electrical device that contains an electric lamp that provides illumination. All light fixtures have a fixture body and one or more lamps. The lamps may be in sockets for easy replacement—or, in the case of some LED fixtures, hard-wired in place.
Speedlight is the brand name used by Nikon Corporation for their photographic flash units, used since the company's introduction of strobe flashes in the 1960s. Nikon's standalone Speedlights have the SB- prefix as part of their model designation. Current Speedlights and other Nikon accessories make up part of Nikon's Creative Lighting System (CLS), which includes the Advanced Wireless Lighting, that enables various Nikon cameras to control multiple Nikon flash units in up to three separate controlled groups by sending encoded pre-flash signals to slave units.
In electronics, an LED circuit or LED driver is an electrical circuit used to power a light-emitting diode (LED). The circuit must provide sufficient current supply to light the LED at the required brightness, but must limit the current to prevent damaging the LED. The voltage drop across an LED is approximately constant over a wide range of operating current; therefore, a small increase in applied voltage greatly increases the current. Very simple circuits are used for low-power indicator LEDs. More complex, current source circuits are required when driving high-power LEDs for illumination to achieve correct current regulation.
Decorative vehicle lighting is lighting which is intended entirely as a decorative or ornamental addition to a vehicle, rather than lighting which is required for safety.
A solar lamp also known as solar light or solar lantern, is a lighting system composed of a LED lamp, solar panels, battery, charge controller and there may also be an inverter. The lamp operates on electricity from batteries, charged through the use of solar photovoltaic panel.
LED art is a form of light art constructed from light-emitting diodes. LEDs are very inexpensive to purchase and have become a new way to make street art. Many artists who use LEDs are guerrilla artists, incorporating LEDs to produce temporary pieces in public places. LEDs may be used in installation art, sculptural pieces and interactive artworks.
HP Mini is a former line of small computers categorized as netbooks manufactured by Hewlett-Packard under the HP brands. They either contained a custom version of Ubuntu Linux, Microsoft Windows XP Home Edition or Windows 7 Starter operating system. Like most netbooks, they were not built with CD/DVD drives. However, HP did sell portable DVD-ROMs with HP's LightScribe disc imaging software. These netbooks are best used for written documents, small programs and web browsing. They can run standard software, but given their low price, they tend to have low end specifications, causing poor performance. They were announced from mid-2007, and marketed from 2008 through 2012.
Smart lighting is a lighting technology designed for energy efficiency. This may include high efficiency fixtures and automated controls that make adjustments based on conditions such as occupancy or daylight availability. Lighting is the deliberate application of light to achieve some aesthetic or practical effect. It includes task lighting, accent lighting, and general lighting.
Solar street lights are raised light sources which are powered by solar panels generally mounted on the lighting structure or integrated into the pole itself. The solar panels charge a rechargeable battery, which powers a fluorescent or LED lamp during the night.
Solar traffic lights are signalling devices powered by solar panels positioned at road intersections, pedestrian crossings and other locations to control the flows of traffic. They assign the right of way to road users by the use of lights in standard colors, using a universal color code.
A dive light is a light source carried by an underwater diver to illuminate the underwater environment. Scuba divers generally carry self-contained lights, but surface supplied divers may carry lights powered by cable supply.
A rope light is primarily used as a decorative lighting fixture, featuring small light bulbs linked together and encased in a PVC jacket to create a string of lights. Rope lights can be used in many applications both indoors and outdoors. Used in place of neon signs, it is sometimes called soft neon.
A Notification LED is a small RGB or monochrome LED light usually present on the front-facing screen bezel of smartphones and feature phones whose purpose is to blink or pulse to notify the phone user of missed calls, incoming SMS messages, notifications from other messaging apps etc. It usually pulses in a continuous way to draw the attention of the user. It is a part of the device's notification system that uses a cloud-powered push notification service to relay remote notification messages to the user or local notifications.