Yes, it could not be good for your eyes. Basically, it interferes with sleep-wake cycle of your brain. And your melation levels rise in the dark that is a part of the natural sleep-cycle, you could not sleep well with the lights on because it would lower your level of melatonin that is produced by the pineal gland in your brain, to interrupt your natural sleep cycle. Sleep in the dark is the only naturally sleep way, thus your eyes have to rest in dark. If you have to sleep with a light on, you had better select a yellow light. Because the blue spectrum light is especially bad for your eyes.
Well, it seems that you are quite puzzled by this question. So, as a matter of fact, it does not cause damage to our eyes if we try to sleep with the lights on in the room. Because this simply causes no harm. However, if we insist on doing this, the quality of sleep would be slightly affected, and maybe we will not be completely relaxed in the following morning. So, I suggest you turn off the lights.
Yes, it is bad for your eyes when you sleep and let the lights on. Although you close your eyes, your eyeballs are still moving. The lights may get into your eyes and affect the sleeping state of your eyes. And the eyes may get stimulated through the eye nerves which will not be good for your eyes to have a good rest.