LED Emitters – Infrared, UV, Visible
1. Infrared Emitters
Principle and Structure:
Energy is released through electron-hole recombination of semiconductor PN junction to generate infrared light with a wavelength range of 0.75~1000μm. The core materials are usually III-V compound semiconductors such as gallium arsenide (GaAs) and gallium arsenide phosphide (GaAsP).
Features:
It has the characteristics of strong linear propagation, high anti-interference ability, low power consumption, and long life, and is suitable for complex environments.
Typical Applications:
Remote control equipment (such as TV remote control), photoelectric switches, security systems (infrared alarms), medical equipment (infrared temperature measurement), etc.
2. Ultraviolet Emitters
Principle and Materials:
Ultraviolet light is generated by the electron transition of wide bandgap semiconductor materials (such as gallium nitride GaN and silicon carbide SiC), and the wavelength range is usually 10~400nm. Its luminous efficiency is directly related to the bandgap width of the material.
Application Areas:
UV curing (such as 3D printing), sterilization and disinfection (water treatment, medical equipment), fluorescence detection (anti-counterfeiting identification), etc.
3. Visible Emitters
Principle and Type:
Based on LED technology, red, yellow, green, and other visible light emissions are achieved by doping different semiconductor materials (such as GaP and GaAsP), with a wavelength range of about 380~750nm. Two-color/three-color LEDs can achieve color switching through multi-PN junction integration.
Packaging and Parameters:
Common packages include surface mount (SMD) and plug-in forms; key parameters include operating voltage (1.8~3.3V), luminous intensity (unit mcd), and viewing angle (such as 30°~120°).
Application Scenarios:
Device status indication (power light, port light), display backlight, lighting (low-power LED light), traffic lights, etc.
4. Technology Comparison and Selection Points
|
Category |
Wavelength Range |
Typical Materials |
Core Parameters |
Typical Scenarios |
|
Infrared Emitter |
0.75~1000μm |
GaAs、GaAsP |
Transmitting Power, Radiation Angle |
Remote Control, Security |
|
Ultraviolet Emitter |
10~400nm |
GaN、SiC |
Bandgap Width, Radiation Efficiency |
Sterilization, Detection |
|
Visible Emitter |
380~750nm |
GaP、GaAsP |
Brightness, Color Temperature, Viewing Angle |
Indicator, Lighting |
Selection Suggestion: Wavelength matching, power consumption, packaging form (such as heat dissipation requirements), and environmental adaptability (such as temperature and humidity) need to be considered comprehensively.
5. Development Trend
High efficiency: Improve light efficiency and wavelength accuracy through new materials (such as perovskite).
Integration: Multi-band emitter integration (such as infrared + visible light composite sensor).
Intelligence: Combined with the drive circuit to achieve dynamic dimming and adaptive control.