CRT Mon darkened suddenly

My CRT Mon, had been used for about 4 yrs, darkened suddenly. I turned it on again and found a orange light twinkled in the light button. It shows green light when it works.

I connected another LCD Mon into the same PC, it is OK.

I connected the darkened Mon to the other PC, it still not work with the orange light twinkled.

I wish to know what had happen to my CRT Mon and how to do on it ?

Chinese reply is appreciated for I don't know Chinese typing.