Study On Accelerated Life Test Of Ring He-Ne Laser

In order to obtain lifetime distribution and life test method of ring He-Ne laser, this paper adopts the accelerated life testing method in a constant stress to handle 15 lasers with the same process of product and the same type. Existing life distribution in the different accelerating current is verified, and life of laser gyro is estimated faster and more accurately.According to the existing experimental conclusion, the lifetime distribution of the laser obeys Weibull distribution and anti-power law at large electric current. As the accelerated stress, current level in 10mA, 8mA and 5mA are selected. Power, cavity pressure drop and current of the laser are collected per 20s. Then test data of life testing are obtained and analyzed.Experimental results show that the changes of the total gas pressure in the cavity lead to that the best work current increase. Gas temperature in the capillary affects power of the laser. The variance of power is small. Therefore, just the value of power is considered when failure criteria of accelerated life test are determined. Under current stress of 0.5-10mA, the laser has been working in normal glow discharge area. In other words, discharge manner is not changed and new failure factors are not produced.In addition, power and cavity pressure drop of each group have the same discipline. Power appears heave before the rapid decline, at the same time, pipe pressure drop appears heave transitorily, and then the quality of the laser fell rapidly. These results provide a good basis for the further study of the characteristics of laser gyro.