2. Long service life: the service life can reach more than 65,438+10,000 hours, which can be described as "once and for all" for ordinary household lighting.
3, can work in a high-speed state: if the energy-saving lamp is frequently switched on and off, the filament will turn black and break down quickly, which is safer.
4. Solid-state packaging belongs to the type of cold light source. Therefore, it is easy to transport and install, and can be installed in any miniature and enclosed equipment without worrying about vibration.
5.led technology is changing with each passing day, the luminous efficiency is making an amazing breakthrough, and the price is also decreasing. The era of white LED entering the home is rapidly coming.
6, environmental protection, no harmful substances containing mercury. The assembly parts of LED bulbs can be easily disassembled and assembled, and can be recycled by others without recycling by manufacturers.
7. Light distribution technology expands LED point light source into surface light source, increases luminous surface, eliminates glare, sublimates visual effect and eliminates visual fatigue.
8. Integrated design of lens and lampshade. The lens has the functions of focusing and protection at the same time, which avoids the repeated waste of light and makes the product more concise and beautiful.
9. High-power led planar cluster package, integrated design of radiator and lamp holder. It fully guarantees the heat dissipation requirements and service life of led, fundamentally meets the arbitrary design of LED lamps' structure and shape, and has the distinctive characteristics of LED lamps.
10, saving energy significantly. Using ultra-bright high-power led light source and high-efficiency power supply, it saves more than 80% electricity compared with traditional incandescent lamps, and its brightness is 10 times that of incandescent lamps with the same power.
1 1, with a long service life of more than 50,000 hours, which is more than 50 times that of the traditional tungsten lamp. LED adopts highly reliable advanced packaging technology-* * * crystal bonding, which fully guarantees the long life of LED.
12, no stroboscopic. Pure DC operation eliminates the visual fatigue caused by stroboscopic light source.
13, environmental protection. Does not contain lead, mercury and other polluting elements, and has no pollution to the environment.
14, impact resistance, strong lightning resistance, no ultraviolet (UV) and infrared (IR) radiation. No filament and glass shell, no damage problem of traditional lamp tube, no harm to human body and no radiation.
15, low hot pressing, safe and reliable. Surface temperature ≤60℃ (when ambient temperature Ta=25℃).
16, wide voltage range, universal LED lamp. Constant current in the full voltage range of 85V~ 264VAC ensures that life and brightness are not affected by voltage fluctuation.
17, adopting PWM constant current technology, with high efficiency, low fever and high constant current precision.
18, which reduces the line loss and has no pollution to the power grid. Power factor ≥0.9, harmonic distortion ≤20%, EMI meets global indicators, reduces power loss of power supply lines, and avoids power grid pollution caused by high-frequency interference.
19, universal standard lamp holder, which can directly replace existing halogen lamps, incandescent lamps and fluorescent lamps.
20. The luminous visual efficiency can be as high as 80lm/w, and the color temperature of various LED lamps is optional, with high color rendering index and good color rendering.
Obviously, as long as the cost of led lamps decreases with the continuous progress of LED technology. Energy-saving lamps and incandescent lamps will inevitably be replaced by LED lamps.
The country pays more and more attention to lighting energy saving and environmental protection, and has been vigorously promoting the use of LED lights.
The types of LED lamps are 1. LED lights are divided according to the luminous color of LEDs.
According to the luminous color of LED, it can be divided into red, orange, green (yellow-green, standard green and pure green) and blue light. In addition, some light emitting diodes contain chips of two or three colors.
According to whether light-emitting diodes are doped with scatterers, colored or colorless, light-emitting diodes of the above colors can be divided into four types: colored transparent, colorless transparent, colored scattering and colorless scattering. Scattering LEDs and LEDs are used as indicator lights.
2.LED lamps are classified according to the characteristics of the light-emitting surface of the light-emitting tube.
According to the characteristics of light-emitting surface of LED, it can be divided into round lamp, square lamp, rectangle, surface LED, side tube and microtubule for surface mounting. The diameter of circular lamp is divided into φ2mm, φ4.4mm, φ5mm, φ8mm, φ 10mm and φ20mm. In foreign countries, light-emitting diodes with a diameter of 3 mm are usually marked as T-1; φ5mm is marked as t-1(3/4); Write φ4.4mm as T- 1( 1/4).
The angular distribution of circular light intensity can be estimated by half-value angle.
From the angle distribution diagram of luminous intensity, there are three types:
(1) high directivity. Generally, it is a pointed epoxy package or a package with a metal reflective cavity, and no scattering agent is added. The half-value angle is 5 ~ 20 or less, which has high directivity and can be used as a local lighting source or combined with a photodetector to form an automatic detection system.
(2) standard type. Usually used as an indicator light, its half-value angle is 20 ~ 45.
(3) Scattering type. This is an indicator lamp with a large viewing angle, with a half-value angle above 45 ~ 90, and a large number of scattering agents.
3. According to the structure of LED
According to the structure of LED, there are full epoxy package, metal-based epoxy package, ceramic-based epoxy package and glass package.
4. According to the luminous intensity and working current
According to the luminous intensity and working current, there are LEDs with ordinary brightness (luminous intensity100 MCD); Luminous intensity between 10 and 100 MCD is called high brightness led. Generally, the working current of LED is in the range of ten milliamps to tens of milliamps, while the working current of low-current LED is below 2mA (the brightness is the same as that of ordinary LED).
In addition to the above classification methods, there are also methods of classification by chip material and classification by function.
Led chip classification
Definition and characteristics of 1 MB chip
Definition:
MB chip: metal bonding chip; This chip belongs to UEC's patented product.
Features:
1. Si with high heat dissipation coefficient is used as the substrate, which is easy to dissipate heat.
conductivity for heat
GaAs: 46/m-g
Gap: 77 W/m-K
Silicon: 125 ~ 150 W/m-K
Copper: 300~400 W/m-g
Silicon carbide: 490 W/m-g
2. The wafer is bonded to the epitaxial layer and the substrate through the metal layer, and at the same time, photons are reflected to avoid absorption by the substrate.
3. instead of GaAs substrate, conductive silicon substrate has good thermal conductivity (thermal conductivity difference is 3~4 times), which is more suitable for the field of high driving current.
4. The metal reflective layer at the bottom is beneficial to improve luminosity and heat dissipation.
5, the size can be increased, and it can be used in high-power fields, such as: 42mil MB.
2.2 Definition and characteristics. GB chip
Definition:
National standard chip: adhesive chip; This chip belongs to UEC's patented product.
Features:
1: transparent sapphire substrate replaces light-absorbing GaAs substrate, and the optical output power is more than twice that of traditional As (absorbable structure) chip. Sapphire substrate is similar to GaP substrate of TS chip.
2: The chip shines on all sides, and the pattern is excellent.
3. In terms of brightness, its overall brightness has exceeded the level of ts chip (8.6mil).
4. The double-electrode structure is slightly worse than the TS single-electrode chip in high current resistance.
3.3 Definition and characteristics. TS chip
Definition:
TS chip: transparent structure (transparent substrate) chip, which is a patented product of HP.
Features:
1. Chip technology is complex, much higher than that of AS LED.
2. Excellent reliability
3. Transparent GaP substrate, which does not absorb light and has high brightness.
4. Widely used
4.4 Definition and characteristics. As a chip
Definition:
AS chip: Absorbable structure chip; After nearly 40 years of development efforts, the R&D, production and sales of this type of chips in the LED photoelectric industry in Taiwan Province Province are in a mature stage, which is basically at the same level as that of major companies in this field, with little difference.
The mainland chip manufacturing industry started late, and its brightness and reliability still lag far behind that of Taiwan Province Province. The AS chip mentioned here is specifically the AS chip of UEC, such as EG: 7 12Sol-VR, 709Sol-VR, 7 12Sym-VR, 709SYM-VR, etc.
Features:
1. Four chips, manufactured by MOVPE technology, with brighter brightness than traditional chips.
2. Excellent reliability
3. Widely used
Epitaxial types of LED chip materials
1, LPE: liquid phase epitaxy (GaP/GaP)
2.VPE: gas phase epitaxy (gas Xiang Lei crystal method) GaAsP/GaAs.
3.MOVPE: Metal-organic vapor phase epitaxy (organic metal gas Xiang Lei crystallization method) AlGaInP, GaN.
4.SH: GaAlAs/GaAs single heterostructure (single heterostructure) GaAlAs/GaAs.
5.DH: GaAlAs/GaAs double heterostructure, (double heterostructure) GaAlAs/GaAs.
6.DDH: GaAlAs/GaAlAs double heterostructure.
Advantages and disadvantages of LED lamps * Heat dissipation problem, if the heat dissipation is not good, the life will be greatly shortened.
* The power saving of low-end LED lamps is still lower than that of energy-saving lamps (cold cathode tubes, CCFL).
* Higher initial purchase cost.
* Due to the strong directivity of LED light source, the special optical characteristics of LED should be considered in the design of lamps and lanterns.
The following is a comparison between neon lights and LED lights. The latest LED technology is added for comparison, which is not the information that everyone saw on the Internet before.
1.Is the life of LED light source 100000 hours?
According to the calculation of 7% light decay, the actual time is only about 50000 hours. According to the light attenuation of 3%, the practical application can reach 80000 hours.
2. won't the 2.led heat up?
Yes, it needs heat dissipation.
3. Can 3.LED replace incandescent lamp?
The luminous flux, luminous efficiency and color rendering are all ok, but it is too expensive and will not decrease in recent years. But the cost of replacing incandescent lamps can be reduced by increasing the luminous flux of products.
4. Can 4.LED be simply used as a common light source?
No, it needs driving power supply, optical LED lamp and heat conduction.
5. Comparison of performance and advantages of two light sources
The advantages of neon lights have been covered by LEDs, but the price of LED lights is too high.
6. Power comparison of two light sources
The low voltage of LED is good, but the load current is too large. The input current of large particle 1 watt LED single lamp is 350mA.
7. Comparison of two light source control technologies
LED is easy to realize, but neon lights are mature.
8. Stability comparison of two light sources
The LEDs are inconsistent, and the neon lights are quite stable. A few manufacturers can be relatively stable, such as combining CREE and AOD chips and taking the advantages of their respective chips.
9. Price comparison of two kinds of light sources
LED is more expensive, but yellow and red are equivalent, and the main expensive is LED white light.
10. Comparison of outdoor use of two light sources
The LED lamp has been completely waterproof and dustproof.
1 1. Comparison of two light source markets
The annual output value of global lighting products is US$ 42 billion (US$ 65.438+0.5 billion in China), and LED light sources account for less than 654.38+0%.