inżynieria: LED lamp

Evidence: 100 • authority: 72

An LED lamp or LED light is an electric light that produces light using light-emitting diodes (LEDs). LED lamps are significantly more energy-efficient than equivalent incandescent lamps and fluorescent lamps. The most efficient commercially available LED lamps have efficiencies exceeding 200 lumens per watt (lm/W) and convert more than half the input power into light. Commercial LED lamps have a lifespan several times longer than both incandescent and fluorescent lamps. LED lamps require an electronic LED circuit to operate from mains power lines, and losses from this circuit means that the efficiency of the lamp is lower than the efficiency of the LED chips it uses. The driver circuit may…

Evidence: 45 • authority: 72

A fluorescent lamp, or fluorescent tube, is a low-pressure mercury-vapor gas-discharge lamp that uses fluorescence to produce visible light. An electric current in the gas excites mercury vapor, to produce ultraviolet and make a phosphor coating in the lamp glow. Fluorescent lamps convert electrical energy into visible light much more efficiently than incandescent lamps, but are less efficient than most LED lamps. The typical luminous efficacy of fluorescent lamps is 50–100 lumens per watt, several times the efficacy of general lighting incandescent bulbs with comparable light output, which is on the close order of 16 lm/W. Fluorescent lamp fixtures are more costly than incandescent lamps b…

Evidence: 38 • authority: 80

Toward 200 Lumens per Watt of Quantum-Dot White-Light-Emitting Diodes by Reducing Reabsorption Loss

Evidence: 38 • authority: 90

Toward 200 Lumens per Watt of Quantum-Dot White-Light-Emitting Diodes by Reducing Reabsorption Loss

Evidence: 33 • authority: 90

Sustainable Lighting for Healthcare Facilities: More Than Just Lumens Per Watt. Abstract Sustainability is, as the name implies, a movement to ensure long-term, efficient utilization of resources. Sustainability does not imply that resources should be restricted nor that resource utilization should be subsidized. Bill McDonough (McDonough and Braungart 2002) has described sustainability in terms of the three E's: environment, equity, and economy. In the last quarter century the lighting industry has dramatically improved the energy efficiency (environment “E”) and life-cycle cost of lighting (economy “E”). Much less attention has been given to the equity “E.” Lighting standards are still se…

Evidence: 33 • authority: 72

Luminous efficacy is a measure of how efficiently a light source produces visible light. It is the ratio of luminous flux to power, measured in lumens per watt in the International System of Units (SI). Depending on context, the power can be either the radiant flux of the source's output, or it can be the total power (electric power, chemical energy, or others) consumed by the source. Which sense of the term is intended must usually be inferred from the context, and is sometimes unclear. The former sense is sometimes called luminous efficacy of radiation, and the latter luminous efficacy of a light source or overall luminous efficacy. Not all wavelengths of light are equally visible, or equ…

Evidence: 26 • authority: 92

A programmable benchtop photocrosslinking chamber for controlled bioconjugation.. Ultraviolet (UV) photochemical reactions have become ubiquitous in the biomedical sciences, where they are frequently used to conjugate biomolecules in a process known as photo-crosslinking. Such processes play an important role in the fields of drug discovery, biomarker validation, and bioprinting. Typically, these photochemical reactions are conducted using commercially available UV irradiation sources which are bulky and expensive. Handheld units are a popular substitute but tend to cause excessive heating of the sample. Additionally, currently available UV sources are not designed to be user-friendly for p…

Evidence: 26 • authority: 80

Let there be light, but just enough: The end of cheap energy gave the lighting industry a corporate headache and the user more lumens per watt

Evidence: 26 • authority: 92

A photon-recycling incandescent lighting device.. Energy-efficient, healthy lighting is vital for human beings. Incandescent lighting provides high-fidelity color rendering and ergonomic visual comfort yet is phased out owing to low luminous efficacy (15 lumens per watt) and poor lifetime (2000 hours). Here, we propose and experimentally realize a photon-recycling incandescent lighting device (PRILD) with a luminous efficacy of 173.6 lumens per watt (efficiency of 25.4%) at a power density of 277 watts per square centimeter, a color rendering index (CRI) of 96, and a LT70-rated lifetime of >60,000 hours. The PRILD uses a machine learning-designed 637-nm-thick visible-transparent infrared-re…

Evidence: 26 • authority: 72

A light-emitting diode (LED) is an electronic component that uses a semiconductor to emit light when current flows through it. Electrons in the semiconductor recombine with electron holes, thereby releasing energy in the form of photons. The color of the light (corresponding to the energy of the photons) 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. Appearing as practical electronic components in 1962, the earliest LEDs emitted low-intensity infrared (IR) light. Infrared LEDs are used in remote-control circuits, such as…

Evidence: 20 • authority: 72

A compact fluorescent lamp (CFL), also called compact fluorescent light, energy-saving light and compact fluorescent tube, is a fluorescent lamp designed to replace an incandescent light bulb; some types fit into light fixtures designed for incandescent bulbs. The lamps use a tube that is curved or folded to fit into the space of an incandescent bulb, and a compact electronic ballast in the base of the lamp. Compared to general-service incandescent lamps giving the same amount of visible light, CFLs use one-fourth to one-third the electric power, and last eight to fifteen times longer. A CFL has a higher purchase price than an incandescent lamp, but can save over five times its purchase pri…

Evidence: 20 • authority: 88

CIE S 025/E:2015 Test Method for LED Lamps, LED Luminaires and LED Modules. This standard provides requirements to perform reproducible photometric and colorimetric measurements on LED lamps, LED modules, and LED luminaires (LED devices). It also provides advice for the reporting of the data. The availability of reliable and accurate photometric data for LED devices is a basic requirement for designing good lighting systems and evaluating performance of products. By obtaining these data through measurements in specific normalized measuring conditions, the consistency of the data should be ensured between different laboratories (within the limits of the declared measurement uncertainty) and…