The concept of the lasing lifetime of working substance in the solid dye laser is promoted to liquid dye laser, and a twin laser beam testing method to measure the lasing lifetime is presented.

The solid dye laser compares to the traditional liquid dye laser, it will have a small size, light weight, easy to operate, compact structure, the use of more reliable and so on.

Based on the theoretical analysis of the dye and the photo-induced fluorescence, a new method for testing the liquid laser dye's lasing lifetime was introduced.