Xenon lamp (xenon flash lamp) is a light source based on the principle of high-voltage gas discharge. The performance of its electrode material directly affects the luminous efficiency, starting speed and service life of the lamp tube. Barium tungsten electrode has become a widely used electrode material in xenon lamps due to its unique physical and chemical properties.
I. Characteristics and Advantages of Barium Tungsten Electrode
1. Excellent Electron Emission Performance
The work function of barium tungsten electrode is low (φ=1.6eV), and its electron emission ability is significantly better than that of pure tungsten electrode, and the current density can reach 10A/cm2. This characteristic enables it to quickly release electrons during high-voltage gas discharge, improving the starting speed and light efficiency stability of xenon lamps.
In addition, barium tungsten electrode has no radioactive pollution and strong anti-poisoning ability, avoiding the radioactive risk of traditional thorium tungsten electrode.
2. High Temperature Resistance and Long Life
When the xenon lamp is working, the temperature of the electrode tip is extremely high. The barium tungsten electrode has significantly improved its high temperature resistance by optimizing the material formula (such as impregnation of barium aluminate) and process.
3. Strong Adaptability
Barium tungsten electrodes can work stably in low voltage environments (such as 10% lower than 220V of mains electricity) and support high brightness output (brightness increased by about 15%). This feature makes it widely used in devices that require fast response, such as cameras, electronic police monitoring lights, and strobe speedometers.
II. Application of Barium Tungsten Electrodes in Xenon Lamps
1. Structure and Working Principle
Xenon lamps are usually composed of quartz tubes, high-pressure xenon gas and electrodes. As the discharge core, the barium tungsten electrode stimulates the xenon gas to react with rare metals to emit light through positive and negative electrical stimulation, replacing traditional tungsten filaments to achieve higher energy conversion efficiency.
2. Performance Improvement Effect
Quick Start: The low work function characteristics of the barium tungsten electrode make the xenon lamp start quickly and significantly improve the instantaneous luminous energy.
Stable Light Effect: The sputtering loss of the barium tungsten electrode is lower, and the light effect can be maintained for a long time.
