This is an audio version of the Wikipedia Article:
[ Ссылка ]
00:01:58 1 History
00:02:06 1.1 Discoveries and early devices
00:07:26 1.2 Initial commercial development
00:10:00 1.3 Blue LED
00:14:50 1.4 White LEDs and the illumination breakthrough
00:17:53 2 Physics of light production and emission
00:18:32 3 Colors
00:19:02 3.1 Blue and ultraviolet
00:21:27 3.2 White
00:22:46 3.2.1 RGB systems
00:25:45 3.2.2 Phosphor-based LEDs
00:29:40 3.2.3 Other white LEDs
00:30:50 4 Organic light-emitting diodes (OLEDs)
00:31:58 5 Types
00:32:49 5.1 Miniature
00:33:59 5.2 High-power
00:35:31 5.3 AC-driven
00:36:27 5.4 Application-specific variations
00:36:37 5.4.1 Flashing
00:37:21 5.4.2 Bi-color
00:38:10 5.4.3 RGB Tri-color
00:39:06 5.4.4 Decorative-multicolor
00:39:27 5.4.5 Alphanumeric
00:40:12 5.4.6 Digital RGB
00:41:08 5.4.7 Filament
00:42:02 5.4.8 Chip-on-board arrays
00:42:31 6 Considerations for use
00:42:41 6.1 Power sources
00:43:27 6.2 Electrical polarity
00:44:03 6.3 Safety and health
00:45:27 6.4 Advantages
00:48:37 6.5 Disadvantages
00:52:09 7 Applications
00:52:48 7.1 Indicators and signs
00:54:44 7.2 Lighting
00:58:33 7.3 Data communication and other signalling
00:59:35 7.4 Machine vision systems
01:00:26 7.5 Other applications
01:03:34 8 Research and development
01:03:43 8.1 Key challenges
01:04:39 8.2 Upcoming technology
01:04:48 8.2.1 Perovskite LEDs (PLEDs)
01:05:32 8.2.2 Two-way LEDs
Listening is a more natural way of learning, when compared to reading. Written language only began at around 3200 BC, but spoken language has existed long ago.
Learning by listening is a great way to:
- increases imagination and understanding
- improves your listening skills
- improves your own spoken accent
- learn while on the move
- reduce eye strain
Now learn the vast amount of general knowledge available on Wikipedia through audio (audio article). You could even learn subconsciously by playing the audio while you are sleeping! If you are planning to listen a lot, you could try using a bone conduction headphone, or a standard speaker instead of an earphone.
Listen on Google Assistant through Extra Audio:
[ Ссылка ]
Other Wikipedia audio articles at:
[ Ссылка ]
Upload your own Wikipedia articles through:
[ Ссылка ]
Speaking Rate: 0.9557085850421818
Voice name: en-AU-Wavenet-A
"I cannot teach anybody anything, I can only make them think."
- Socrates
SUMMARY
=======
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. This effect is called electroluminescence. 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 light. Infrared LEDs are used in remote-control circuits, such as those used with a wide variety of consumer electronics. The first visible-light LEDs were of low intensity and limited to red. Modern LEDs are available across the visible, ultraviolet, and infrared wavelengths, with high light output.
Early LEDs were often used as indicator lamps, replacing small incandescent bulbs, and in seven-segment displays. Recent developments have produced white-light LEDs suitable for room lighting. LEDs have led to new displays and sensors, while their high switching rates are useful in advanced communications technology.
LEDs have many advantages over incandescent light sources, including lower energy consumption, longer lifetime, improved physical robustness, smaller size, and faster switching. Light-emitting diodes are used in applications as diverse as aviation lighting, automotive headlamps, advertising, general lighting, traffic signals, camera flashes, lighted wallpaper and medical devices.Unlike a laser, the color of light emitted from an LED is neither coherent nor monochromatic, but the spectrum is narrow with respect to human vision, and functionally monochromatic.
![](https://s2.save4k.ru/pic/vCn0r2Imqag/mqdefault.jpg)