Light emitting diodes are simply referred to as LEDs. A diode made of gallium (Ga) and arsenic (As), phosphorus (P), nitrogen (N), and indium (In) compounds can radiate visible light when combined with electrons and can be used to make led. In the circuit and instrument as a light, or composition of text or digital display. Phosphorus and gallium arsenide diodes emit red light. Phosphorized germanium diodes emit green light. Silicon carbide diodes emit yellow light and indium gallium nitride diodes emit blue light.
Design theory
With the advent of LEDs, the lighting design theory is also evolving with the advantages of LEDs.
1. Scenario Lighting: Designing lighting fixtures based on the needs of the environment. Scenario lighting takes place as a starting point and aims to create a beautiful and beautiful lighting environment to enhance the scene effects and make people feel that there is a scene atmosphere.
2. mood lighting: [2] to design lighting fixtures based on people's needs. Atmospheric lighting is based on human emotions, from the perspective of people to create a mood-like lighting environment. The mood lighting is different from the scene lighting. The mood lighting is dynamic. It can satisfy people's spiritual needs. It makes people feel sentiment; while the scene lighting is static, it can only emphasize the needs of the scene lighting, but can not express Human emotions, in a sense, mood lighting cover scene lighting. Affective lighting includes four aspects: First, environmental protection and energy conservation; second, health, third, intelligence, and fourth, humanization.
advantage
First, the small size of the LED is basically a small wafer that is encapsulated in epoxy resin, so it is very small and very light.
Second, low power LED power consumption is quite low, in general, LED operating voltage is 2-3.6V. Only very weak currents are needed for normal light emission.
Third, the long service life Under the appropriate current and voltage, LED's life of up to 100,000 hours.
Fourth, high-brightness, low-calorie LED using cold light technology, the heat is much lower than the same power ordinary lighting.
Fifth, environmental protection LED is made of non-toxic materials, unlike fluorescent lamps containing mercury will cause pollution, while the LED can also be recycled.
6. The rugged LED is completely encapsulated in epoxy, which is stronger than bulbs and fluorescent tubes. There are no loose parts in the lamp body. These features make the LED unbreakable.
application
In the more than 10 years since the advent of LED in the 1960s to the 1980s, LEDs have only red, yellow, and green colors, luminous efficiency is very low (only about 1lm/W), brightness is relatively low, and the price is high. People just Use it as an indicator light for electronic products. From the LED development and application process point of view, this period is the LED application phase.
1. AC power indicator When the circuit is connected to a 220V/50Hz AC power supply line, the LED will be turned on to indicate that the power is on. The resistance of the current limiting resistor R is 220V/IF.
2, the AC switch indicator with LED for incandescent light switch lamp circuit, when the switch off the light bulb goes out, the current through the R, LED and light bulb EL to form a loop, LED light, easy to find switches in the dark. At this time, the current in the loop is very small and the light bulb will not light up. When the switch is turned on, the light bulb is lit and the LED goes off.
3. The AC power socket indicator uses a two-color (common cathode) LED as the circuit of the AC power socket indicator. The power supply to the outlet is controlled by switch S. When the red LED is on, the socket is not powered; when the green LED is on, the socket is powered.
4. The fuse-seat indicator LED is used as the circuit for the fuse indicator of the fuse box of the switch box in the factory equipment. When the fuse is intact, the LED will not light; when the fuse is blown, the LED will be illuminated to indicate which fuse the user has blown for replacement. This is very convenient for porcelain core fuses that cannot be observed with the naked eye.
