Eye mask can reduce the light intensity and isolate you in a darkness environment, so as to induce your brain into sleep.
Generally, eye mask is all right. But for people with presbyopic, it is not suitable. For people with myopia, wearing eye mask can improve sight by gently impressing eye balls. But for old people, bit by bit the lens of eyes would become harden. If the lens were pressed, its capacity would serious bad.
Many other things can help to sleep, like peaceful music, gentle exercise and reading. If you still wanna an eye mask, purchase one whit cotton fibre, because the skin around eyes are very tender.
It depends yourself. If you a person who want to sleep in a very dark environment, wearing mask can help you get good sleep. But you must be care when you choose eye mask. You shall choose quality eye mask and avoid anything that is scratchy or likely to cause you sweat during the night. Besides, you shall also avoid any eye mask that too thin or too tight. And cotton eye masks are consider the best choices.
In my opinion, it is not a good idea to wear the mask when sleeping. Wearing the eye mask, it is not useful for the eyes to get breathe although they are in the close state. And it is bad for the skin around the eyes. Thus, you'd better not do this.