LED purple light has certain effect on sterilization
Long wave ultraviolet with wavelength of 380~320nm is called UVA for short,
The UVB with the wavelength of 320~280nm is called UVB for short,
Short wave ultraviolet ray with wavelength shorter than 280nm is called UVC for short.
Most of the ultraviolet disinfection lamps sold on the market use 254nm short wave ultraviolet (UVC) emitted by mercury lamp to achieve disinfection. This UVC ultraviolet light has a short wavelength and carries a large amount of energy.
But just because of this, this kind of short wave ultraviolet lamp will cause direct harm to human body without protective measures:
1. If people's eyes and skin are exposed to ultraviolet light for more than 3 minutes, they may exceed the human safety limits set by the World Health Organization and the International Commission for the Protection of SARS Radiation;
2. After 15 minutes of direct irradiation, the cornea will be damaged, causing electric ophthalmia, sudden severe pain in both eyes, foreign body sensation, photophobia, lacrimation or blepharospasm;
3. Long term irradiation will damage eyes and skin, resulting in eye trauma and serious skin burns, and may lead to skin cancer.
Welding method of LED lamp beads
There are many welding methods for LED lamp beads on the chip, and the following is one of the commonly used methods for reference. First, use an electric soldering iron to heat some soldering tin on the positive and negative electrode pads of the lamp bead (the soldering tin must not be too much, otherwise, the positive and negative electrode pads will be connected once heated with a hot-air gun), then use a hot-air gun to heat the positive and negative electrode pads at the same time, after the tin melts, use tweezers to place the positive and negative electrodes of the lamp bead on the corresponding pad.
LED beads change color? These six reasons are worth noting
LED is the light emitting diode, which is a semiconductor solid light emitting device that converts electric energy into light energy. Its core is the PN junction. In addition to the forward conduction, reverse cut-off and breakdown characteristics of the general PN junction, it also has the light emitting characteristics under certain conditions. Its structure mainly includes the following parts: lead, bracket, encapsulation glue, bonding wire, LED chip, solid crystal glue and phosphor. The discoloration failure of LED lamp bead is closely related to its material, structure, packaging process and service conditions. The following will analyze the causes of its discoloration through specific cases.
Common types and application fields of LED lamp beads
There are many kinds of LED light sources. Different LED lights have slight differences in the lamp beads used in their internal structures. Today, I will make a comprehensive and systematic scientific introduction to the common types of LED lamp beads for your reference.
LED lamp beads are also called light emitting diodes. It has a wide range of applications. Its luminous colors include red light, emerald green light, yellow green light, yellow light, purple light, blue light, white light and orange light. The above is monochromatic light. It can also be made into two or three colors.
How to identify whether LED lamp beads are pure gold
The gold wire used to package LED lamp beads contains more than 99.99% gold. It is produced by drawing gold from this material. In addition to 99.99% gold, this gold also contains less than 1% other trace elements. One of the core components of LED lamp bead packaging is gold wire, which is the bridge connecting the luminous chip and the welding point, and plays a decisive role in the service life of LED lamp bead. So how to identify the purity of gold thread?