LED light (Light Emitting Diode), also known as light-emitting diode, is a solid-state semiconductor device that can directly convert electricity into light. The heart of the LED is a semiconductor chip, one end of the chip is attached to a bracket, one end is the negative electrode, and the other end is connected to the positive electrode of the power supply, so that the entire chip is encapsulated by epoxy resin. The semiconductor wafer consists of three parts, one part is a P-type semiconductor, in which holes dominate, the other end is an N-type semiconductor, which is mainly electrons, and the middle is usually a quantum well of 1 to 5 periods. When the current acts on the wafer through the wire, the electrons and holes will be pushed into the quantum well, where the electrons and holes recombine, and then emit energy in the form of photons, which is the principle of LED light emission.
LED lamps have many advantages such as small size, low power consumption, long life, non-toxic and environmental protection. LED lamps have gradually developed from outdoor decoration, engineering lighting, to household lighting.
Energy-saving lamps, also known as compact fluorescent lamps (abbreviated as CFL lamps abroad), have the advantages of high luminous efficiency (5 times that of ordinary bulbs), obvious energy-saving effect, long life (8 times that of ordinary bulbs), small size, and easy use. It works basically the same as a fluorescent lamp.
In addition to white (cold light), energy-saving lamps now have yellow (warm light). Generally speaking, under the same wattage, an energy-saving lamp is 80% more energy efficient than incandescent lamps, the average life span is 8 times longer, and the heat radiation is only 20%. Under non-strict conditions, a 5-watt energy-saving lamp can be regarded as equal to a 25-watt incandescent lamp, a 7-watt energy-saving lamp is approximately equal to 40 watts, and a 9-watt energy-saving lamp is approximately equal to 60 watts.
Fluorescent lamp is also called fluorescent lamp, its working principle: fluorescent tube is simply a closed gas discharge tube. The main gas in the tube is argon (argon) gas (including neon or krypton) and the pressure is about 0.3% of the atmosphere. Also contains a few drops of mercury - forming traces of mercury vapour. Mercury atoms make up about one thousandth of all gas atoms.
The fluorescent tube is relying on the mercury atoms of the lamp tube to release ultraviolet light (the main wavelength is 2537 angstroms = 2537 × 10-10m) by the process of gas discharge. About 60% of the electricity consumed can be converted into ultraviolet light. Other energy is converted into heat energy.
Fluorescent lamps emit visible light after absorbing ultraviolet light by fluorescent substances on the inner surface of the lamp tube. Different fluorescent substances emit different visible light. Generally, the conversion efficiency of ultraviolet light to visible light is about 40%. So the efficiency of fluorescent lamps is about 60% x 40% = 24% - about twice as much as tungsten lamps of the same power.
Incandescent lamps are also called electric light bulbs. Its working principle is that heat is generated when the current passes through the filament (tungsten filament, the melting point is more than 3000 degrees Celsius). When it is in the state, it emits light like red-hot iron can emit light. The higher the temperature of the filament, the brighter the light emitted. It is called incandescent lamp. When an incandescent lamp emits light, a large amount of electrical energy will be converted into heat energy, and only a very small part (maybe less than 1%, not calculated) can be converted into useful light energy.
The light emitted by incandescent lamps is full-color light, but the composition ratio of each color light is determined by the luminescent material (tungsten) and temperature. The unbalanced ratio causes the color cast of the light, so the color of the object is not realistic enough under the incandescent light.
The life of an incandescent lamp is related to the temperature of the filament, because the higher the temperature, the easier the filament is to sublimate. The process of blackening at both ends of the fluorescent lamp is as follows: the sublimation of the tungsten filament directly becomes tungsten gas, and the tungsten gas is sublimated on the lamp tube wall with a lower temperature and then becomes black. When the tungsten filament sublimates to a relatively thin When thin, it is easy to burn out when powered on, thus ending the life of the lamp. So the power of incandescent lamps is higher.
