There are many kinds of lamps and lanterns on the marke […]
There are many kinds of lamps and lanterns on the market nowadays. When we choose lamps and lanterns, we often don't know where to start. What kind of lamps and lanterns are more suitable for us? What kind of lamps should be used in different environments? Next, I would like to give you a brief introduction to some common lamps and lanterns on the market.
1. Incandescent lamp
The luminous principle of incandescent lamp is to heat filament to incandescent state and use thermal radiation to emit visible light.
It's the kind of light bulb that we used when we were young. It's the incandescent light bulb that burns out the filament after a long time. Less than 10% of the energy it consumes can be converted into light (only 2% of ordinary incandescent lamps), while the rest is lost in the form of heat. Meanwhile, the higher the filament temperature is, the faster the tungsten filament evaporates, which shortens the service life of most incandescent lamps. So although incandescent lamps have many advantages --- color light is closest to sunlight color, good color rendering, uniform spectrum but not abrupt --- the waste of energy is huge. Since the beginning of 2007, the Australian government took the lead in announcing the complete elimination of incandescent lamps in the form of legislation, and more than a dozen countries and regions have issued incandescents one after another. Lighting elimination plan. China has also phased out the phase-out plan since 2011. From October 1, 2016, it is prohibited to sell and import incandescent lamps for general lighting of 15 watts or more.
Summary: If you want to use an incandescent lamp as a light source, there will indeed be purchase difficulties in the future.
Halogen lamps can be seen as an upgraded version of incandescent lamps. Halogen bulb or halogen lamp, also known as tungsten halogen bulb and quartz bulb, is a variant of incandescent lamp. The principle is to inject halogen gas such as iodine or bromine into the bulb. At high temperature, the sublimated tungsten wire reacts with halogen. After cooling, the tungsten will be re-solidified on the tungsten wire, forming a balanced cycle to avoid premature fracture of the tungsten wire. So halogen bulbs live longer than incandescent bulbs (almost four times as long as incandescent bulbs), and because filaments can work at higher temperatures, they get higher brightness, higher color temperatures and higher luminous efficiency.
As an upgraded version of incandescent lamp, halogen lamp has all the advantages of incandescent lamp, but halogen lamp also inherits the disadvantages of incandescent lamp: short life (although longer than incandescent lamp), low luminous efficiency (although higher than incandescent lamp), and halogen lamp because it is also a source of thermal radiation, in lighting or just out, because of the lamp. Bubble temperature is still very high, you can never touch it by hand.
In addition, incandescent lamp and halogen lamp have a small amount of ultraviolet (UV) and infrared (IR) radiation problems. Easily lead to facial skin problems, coupled with ultraviolet radiation, and may even lead to extreme conditions such as sunburn dermatitis.
Summary: If halogen lamp is to be used as light source, at least UV protection treatment is needed - in short, the light emitting part of the lamp head should have a layer of ground or partially ground glass panels with UV resistance.
3. Common fluorescent lamps
The long tube we used as children is fluorescent lamp, also called fluorescent lamp. The traditional fluorescent lamp is a low-pressure mercury lamp. It uses low-pressure mercury vapor to release ultraviolet rays after electrification, so that the phosphor emits visible light. Therefore, it belongs to low-pressure arc discharge light source.
Ordinary fluorescent lamp tubes are coated with halogen fluorescent powder and filled with argon and krypton-argon mixed gases. Light color: cold daylight fluorescent lamp tube, warm daylight fluorescent lamp tube. Although fluorescent lamps are much more efficient than incandescent lamps because they are not scalding, their color rendering performance is lower and their color rendering index R value is less than 40. Far less than the standard value of sunlight, the color rendering index R = 100. Watch the color of the surface of the color object to produce color bias. The color is blue and grey, and the color is dim and not bright. These two fluorescent lamps do not belong to high-efficiency energy-saving electric light source and do not meet the technical requirements of green lighting.
Summary: Not enough energy-saving and environmental protection, do not recommend the purchase.
4. Energy-saving lamp (CFL lamp)
The name "energy-saving lamp" has been widely used in light sources other than incandescent halogen lamps, such as the ubiquitous term "LED energy-saving lamp". The energy-saving lamp here is a compact three-primary electronic fluorescent lamp (CFL lamp for short) which is a compact fluorescent lamp with ballast.
In detail, CFL lamp is a single-ended compact energy-saving fluorescent lamp. The lamp tube, ballast and lamp head of the fluorescent lamp are closely integrated (the ballast is placed in the lamp head). They can not be disassembled except for destructive strikes, so they are called "compact" fluorescent lamps. Since no ballast is needed and the driving circuit is also in the ballast, the fluorescent lamp is also self-ballasting fluorescent lamp and internal starting fluorescent lamp. The whole lamp is directly connected to the power supply network through E27 lamp holder, which can conveniently replace the incandescent lamp directly. This kind of fluorescent lamp mostly uses rare earth element tricolor phosphor, so it has energy-saving function, so it is called "energy-saving lamp". Energy-saving lamps are smaller in size, more energy-saving than incandescent lamps, and longer in life than incandescent lamps. However, the shortcomings are also obvious: as a kind of fluorescent lamp, mercury is added to the tube. In the absence of a good recycling mechanism, the environmental pollution caused by mercury can not be ignored. In addition, the ballast used in the energy-saving lamp will produce certain electromagnetic radiation when it produces instantaneous high pressure.
Summary: Containing harmful substances such as mercury, which is harmful to the environment and produces certain electromagnetic radiation, it is not recommended to buy.
5. LED Lamp
LED is the abbreviation of light emitting diode. Light-emitting diode (LED) is a kind of solid-state semiconductor device which can convert electric energy into visible light. It can directly convert electricity into light.
The heart of the LED is a semiconductor wafer. One end of the wafer is attached to a bracket, one end is negative, the other end is connected to the positive pole of the power supply, so that the whole wafer is encapsulated by epoxy resin. Semiconductor wafers consist of two parts, one is P-type semiconductor, in which holes dominate, and the other is N-type semiconductor, where electrons dominate. But when the two semiconductors are connected, a P-N junction is formed between them. When the current acts on the chip through the wire, the electrons are pushed to the P region, where the electrons recombine with the holes and then emit energy in the form of photons, which is the principle of LED luminescence.
Because of the low calorific value of the LED lamp, the energy can be converted into light as much as possible, so the LED and so on are often referred to as "LED energy-saving lamp". When purchasing energy-saving lamps, it is important to distinguish between LED and CFL, which are completely different light sources. Also known as energy-saving lamp, compared with CFL lamp, LED lamp environmental protection does not contain mercury, can be recycled, which is probably a major driving force for countries to vigorously develop LED lamp. LED lamps have many advantages, mainly the following points:
Green environmental protection: small glare, no radiation, no harmful substances in use.
(2) Long life, stable performance, no shortcomings such as burnable filament, thermal deposition, light decay, etc.
(3) Multi-change: LED light source can use the principle of red, green and blue to produce different color, intensity and color temperature under the control of computer technology.
Summary: There are many advantages, but the disadvantage is that the price is slightly higher than the above lamps, but in the long run, the electricity cost saved can be repaid quickly.