A lot people need a white light source when Development of LED project. Development of white LED in 1998. This LED is made by a GaN chip and yttrium aluminum garnet (YAG) package together. GaN chip as blue (p=465nm, Wd=30nm) lightl, high temperature sintering made of YAG containing Ce3+ phosphor emitting yellow light emission  by this blue light, peak 550nm.Blue LED substrate is mounted in the reflective cavity bowl, covered with a thin layer of resin mixed with YAG, about 200-500nm. The blue part of the LED substrate is absorbed by the phosphor,and the other part is mixed with the yellow light can geted white.adjust the thickness of the phosphor layer and changing the YAG phosphor chemical composition of the phosphor layer can the 3500 – 10000 K color temperature colored white.  Import thing is the medium that between the two poles of the light-emitting diode, powder, and called the phosphor, different media emit different colors of light.

In the past a long time, people’s awareness of UV is vague,Dangerous, even harmful. Even the sunlight is dangerous to them!They does not know that there is a beneficial side of ultraviolet radiation on the human body. can help bone growth
First, Medium wave of ultraviolet radiation,can make the deoxy cholesterol into vitamin D in skin. vitamin D enhances the absorption of calcium and phosphorus in the body,growth of children More contact with sun,more activities on outdoors.help prevent rickets.Recently, office’workers in the incidence of rickets has increased, the reason is * closed working environment
*they’s almost con’t touch the sun All day.

Secondly, different wavelength UV-A, UV-B ultraviolet radiation can treat rheumatoid arthritis, lupus, psoriasis, scleroderma, vitiligo, pityriasis rosea and cutaneous T cell lymphoma and skin diseases. But studies suggest a link to  lupus erythematosus shows that patients treated with ultraviolet radiation can significantly reduce the symptoms. and with the extension of treatment time, the effectiveness of the treatment continues to increase.

Again, UV Can also make the microbial cell nucleic acid and protein puree chemical change, to kill microorganisms, uv led strip were conducting an
Sterilization on air, water and polluted surface.

In summary, the three bands of A, B and C have a qualitative damage to the surface of the biological. The most effective band of the three bands is C band, and the wavelength is 253nm. The bactericidal activity of 7Nm was the strongest.

Molecular absorption of electromagnetic wave, from a kind of physical phenomenon known as “resonance” .For example, we used to say don’t Marchwhen a large force across the bridge.This is afraid of thepace of vibration and vibration bridge together, (vibration always exists objectively, just some weak so it is difficult for us to feel, but the instrument can measure.)then “overlay”.Load increases  bridge vibration cause landslides. This is a common “resonance” phenomenon.

Similarly, there is also a “vibration” of a different kind of energy levels in molecules inside,  equal to the energy of two different energy level difference when Externally added energy .the molecules will absorb the Externally added energy , which is the “resonance”  of atomic molecular level.Ozone can absorb ultraviolet light, which is due to the molecular structure that it can be Produce the “resonance” with the ultraviolet radiation(within a certain range).ozone be skilled in, just absorb specific part. However, it absorbs part happens could lead to skin cancer, that means a lot coming from “murderer”, We think it exists for many kinds of molecules. The mean,  just different for absorbing electromagnetic wave.

About Ozone we knows that it is atmosphere‘live be short of Ozone（the atmosphere is both indispensable (ozone layer)），and it is also a kind of environmental pollutants, some people said oxygen can produce ozone in the ultraviolet irradiation, does that mean to the face of the earth。In here have enough oxygen, The oxygen would be have reacted Above.
thus ozone is an air pollutant, so that the ozone is harmful, and some people say that ozone can absorb ultraviolet light, The conclusions that It was just supposed to be the high-altitude ozone layer(the Earth’s surface from the 14- 25 km altitude).ozone layer, the ozone layer in the earth’s outer space, the sun’s ultraviolet radiation Creating a ozone layer in the earth  Outer space.

Until the atmosphere is stable,the ozone layer is security blanket for people live. in normal circumstances . The ozone layer is stable; it is always to protect people from ultraviolet rays.So, “ozone can absorb ultraviolet rays, ultraviolet Produce ozone” is not contradictory, but these two reactions occur in different position in the atmosphere, There is no relationship between the two.

Hang my clothes lay in the sun,  the use of which the ultraviolet disinfection. Everybody knows that. Well done. Hoo-rah.  But I still have doubts that the ultraviolet disinfection is probably a little andfiniteBut in recent days of an experiment, let me taste of the power of ultraviolet rays in sunlight! (Of course, the experiment is not to measure ultraviolet).
Recently, we manufactured it —–PCB with photographic blue oil, To the exposure, I do not have use UV LED strip. When exposure, I no ultraviolet light – follow www.ledlightmake.com  production of information, just need a few minutes with 8W UV LED to exposure. Other Information also mentioned that if user no have ultraviolet LED light, you can use sunlight or energy-saving lamp to exposure. First I chose to use 12-watt energy-saving lamps to exposure. after 5 minutes, but no effect.Then we had to choose sunlight exposure. The first time to use Sunlight  no experience, the sun for 5 minutes, the exposure is over, 2 minutes is the best time of exposure for PCB.I can’t believe 2 minutes did this. We  would think that PCB stayed there for half an hour.

What are the purpose of the electronic products aging?
Aging (Burn in) is a kind of environmental stress screening. But now a lot of companies have to “aging” the meaning of the word expansion, aging on the equivalent of environmental stress screening, environmental stress screening commonly known as aging, we use the word “aging”.
In the process of electronic products, due to the complicated process and use of plenty material .will introduce various defects (ever get like thatgood the product design). Whether it is manufacturing defects or defects in components, can be divided into obvious defects and latent defects, obvious defects those defects cause the product does not work properly, such as short / open(circuit). products can be used temporarily ，these conditions（potential defects） existed. defects will soon be exposed in-use, the product can not work,
such as insufficient solder, although the product can be used, but a slight vibration may cause the short among solder joint. The obvious defects can be checked by ICT (In- Circuit Test which is a standard test method for testing the defects and poor components of the production.),
It mainly checks the single component and circuit network, and short-circuit condition, with the operation of simple, fast, accurate and fast fault location, FT, etc.. Potential defects are not found by routine inspection, but the use of aging to eliminate. In fact,the aging purpose—– there is a more important purpose (just like test): continually renew this processing technical with aging .perfecting the Product quality。

Why bluish purple light when uv led strip l started working here?

UV electromagnetic spectrum wavelength from 10nm to 400nm, is not visible We can’t be seen any ul lights in the region,in Conventional thinking The UV led should not be visible, so why we use UV led strip is visible blue-violet light? in general hospital use of sterilization lamps (low pressure mercury lamp), there are blue-violet light it?
We know that the main peak of ultraviolet germicidal lamps as  254nm .the power range of ultraviolet sterilization lamp from 4W ~ 100W, the main function is to sterilization, disinfection, clean air. UV is not visible light, in fact the ultraviolet light able to penetrate the ultraviolet quartz glass tube, the low-pressure mercury lamps that emit mercury spectra after electron bombardment, in addition the mercury spectrum ultraviolet, there are have another visible to the human eye .as such 405,435, 545nm light into the visible range, which includes the blue and violet light, so the ultraviolet light look very pretty pale blue.
And the real effect is not visible. in the ultraviolet 254nm. Sterilizing lamp Can be made into the whole ultraviolet ray in the technology,why not do it? short-term large dose, long-term small dose hurting people.

A buyer had been bought that 365NM UV flashlight unexpectedly is 375NM UV flashlight(use 375NM UV led).We know the truth now,many buyers do not have the professional knowledge of the uv led and related professional equipment, unable to identify that 365NM & 375NM ultraviolet.
Now we discuss the differences point of 365NM, 375NM UV LED .365NMwould be better suited for a special occasions and detection Effect is better.  Currently,365NM & 375NM is it was used paper money, high-grade alcohol and tobacco , amber emerald gemstone inspection, That’s why the user are buying (uv led)? the two bands can meet the requirements basically,many buyers Can’t distinguish between the uv 365NM & 375NM. so at special occasions, the 375NM uv led strip can’t meet requirements.
Follow on ，talk about uv 365nm, Effect is betterwhen its use in industry.  some glue or ink curing, parts scar detection, fluid trace detection (including pipeline leak detection, forensic testing and other aspects of the traces fluids 。they needed more strong uv led to operate. The 365NM Is preferred.

Finally, have a simple for you. As follows:

Observation results:
*Green fluorescence with bright, green lines is very clear with 365nm ultraviolet light.

*Green fluorescence, the green lines is not clear, when use the 375nm ultraviolet light.

12PCS smd5050 led 、（Are you ready for that?）

Mounted on the lamp plate,  and  use 3M double-sided adhesive on the back

Final result！

Characteristics of UV led strip disinfection

Bactericidal effect of Ultraviolet led strip is stronger, but the object of penetration is weak. It applies to the operating room, burn unit, space disinfection of infectious diseases between rooms and sterile and non-heat-resistant materials and countertop surface disinfection.
ultraviolet absorption and coincidence photochemical sensitivity range have crossed between UV led strip disinfection’ band with DNA of microbial nucleus.The absorption spectrum of DNA was 240~280nm and the absorption peak was 260nm.It is commonly considered that UV led strip can change and destroy the structural , change the genetic transcription of the cells, and make the organism lose protein synthesis and reproduction ability, other protein absorption (phenylalanine, tryptophan and tyrosine in the absorption peak of 280nm) may also play a role in UV disinfection process.InGeneral , The wavelength of sunlight ultraviolet radiation reaching the surface of the ground is 287~390nm, and the wavelength of ultraviolet radiation is about 250~285nm.
the absorb function of atmospheric ozone layer which can reduce the intensity rate of 290nm UV, so the sterilization ability of the sunlight is less than that of the 290nm uv led.