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How do I identify an LED?
A LED does not have a “Positive” or “Negative” lead. It has a lead identified as the “Cathode” or Kathode” or “k”. This is identified by a flat on the side of the LED and/or by the shortest lead. This lead goes to the 0v rail of the circuit or near the 0v rail (if the LED is connected to other components).
What is the blue LED light called?
Narrow-spectrum blue light (also called blue LED light or short-wavelength LED light) is a type of high-energy visible light, defined as having a wavelength between 400 and 450 nm. This light is common in LEDs (even when used in illumination products) as a carry-over from computer-screen technology.
What is the current of blue LED?
This is a very basic 5mm LED with a blue lens. It has a typical forward voltage of 3.4V and a rated forward current of 30mA.
What is a blue LED?
LEDs have a longer lifespan, emit less heat, and use less electricity than both incandescent and compact fluorescent light sources. The invention of blue LEDs meant that blue, red, and green could all be combined to produce white LED light, which can function as an alternative energy-saving light source.
Which leg of an LED is positive?
anode
The longer leg is the positive side of the LED, called the “anode,” and the shorter leg is the negative side, called the “cathode.” Within an LED, current can only flow from the anode (positive side) to the cathode (negative side) and never in the opposite direction.
Is blue light bad for your skin?
Research shows blue light from electronic devices can lead to changes in your skin cells, including cell shrinkage and death. These speed up the aging process. Even exposures as short as 60 minutes can trigger these changes. Too much blue light could also lead to pigmentation.
What is special about a blue LED?
Blue LED’s offer a new generation of energy efficient and low carbon footprint LED solutions including lightbulbs. Without blue LED’s the LED based TV and computer screens wouldn’t mix three colours to produce white light. Blue lighting also encourages phosphorus to produce white light.
Do blue LEDs use more power?
I assume it’s because you need to use a resistor to drop the voltage more for red and green LEDs then you do for blue LEDs. The LEDs going out as the battery drains is because the forward voltage is higher for blue and green LEDs, not because the battery can’t power them.
Why are white LED light companies advertising lumens?
You may find white LED companies advertising Lumens because they can “beat” the other fixtures that emit mostly red and blue light. A Red/Blue light will score a low amount of lumens.
Where does the white light in LEDs come from?
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.
What kind of light can a led be used for?
LEDs are used in applications as diverse as aviation lighting, fairy lights, automotive headlamps, advertising, general lighting, traffic signals, camera flashes, lighted wallpaper, horticultural grow lights, and medical devices. Unlike a laser, the light emitted from an LED is neither spectrally coherent nor even highly monochromatic.
How does a light emitting diode ( LED ) work?
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.