You as a parent must pay attention to him. The computer glasses will protect his eyes to a certain extent, but you should fundamentally reduce his time of playing the PSP to prevent from myopia.
Anti-blue light glasses can filter out some harmful blue light, so as to protect his eyes. But you should take him out for exercises, the suitable UV exposure plays an important role in his eye development and health.
We all know that computer glasses can effectively reduce the sustained damage of blue light to the eyes, so you should buy a pair for him. But the most important is, you should focus on his daily life of eye sanitation, and reduce the use time of digital product to prevent myopia.