The level of consciousness needed to lucid dream is well REM, stage 1 (yet 5) sleep. Because that's when dreams occur (to the degree of you being able to remember based on your mental strength and cooperatively level of self-awareness) hence you'd really only be able to sleep before waking up to your brain emitting immense low voltage high frequency beta waves, the state of wokeness.
You see, stage 1 sleep is Prominent theta waves that finally deepen your drowsiness (alpha waves) and light sleep occurs, but stages 2-4 finally finish, and your brain goes back to stage 1, but that's stage 5, REM. Or Rapid Eye Movement, it is caused by High Frequency low amplitude beta waves that resemble the waves of a person who is awake.