What replaced radium in watches?

In the realm of horology, radium once held a unique place as a source of luminescence, providing a glow in the dark for decades. However, with the discovery of its harmful effects on human health, the question arises: what material emerged to replace this radioactive element in watches? Did the industry turn to safer alternatives such as tritium or super-luminova? Or did they explore entirely new technologies to achieve a similar effect? Understanding the shift in materials used for watch illumination is crucial in appreciating the evolution of this intricate timepiece.