Gravitational waves are a type of matter wave generated by the violent motion and changes of matter and energy. Detecting gravitational waves allows humanity to observe the universe from a new perspective. During the process of gravitational wave detection, high-energy particles and cosmic rays in space can penetrate the spacecraft's exterior and reach the surface of the inertial sensor's test mass (TM), causing them to continuously accumulate charge. Once the charge on the TM exceeds a certain threshold, the electrostatic forces between the TM and surrounding conductors generate significant acceleration noise, which adversely affects the measurement accuracy of the inertial sensors and, consequently, the success of the gravitational wave detection mission. Therefore, controlling the charge on the TM surface, known as charge management, is essential. The most commonly used charge management method is based on the photoelectric effect, using ultraviolet (UV) light to control the potential between the surface of the TM and the surrounding conductors. In previous charge management systems (CMS), UV mercury lamps and UV light-emitting diodes (LEDs) have been used as light sources with varying levels of success. This paper primarily reviews the research progress of UV light sources in CMS for space gravitational wave detection. Mercury lamps, as the first-generation system light source, can fulfill the mission but have drawbacks such as slow startup, high power consumption and significant electromagnetic interference. UV LEDs, with their advantages in size and weight, have gradually become the current light source for CMS. In recent years, with advancements in UV micro-LED technology, their higher external quantum efficiency and lower power consumption have demonstrated potential for application in CMS, making them one of the promising UV light sources for future charge management systems.
