Lucid dreaming is the phenomenon where you are aware that you are dreaming while you are actually dreaming.
Many people have the ability to be aware while they are dreaming deliberately. While others can get aware only by coincidence.
However, there are many techniques to train your brain to become aware while asleep.
One of those techniques is creating a signal that triggers while you are at the REM Rapid Eye Movement stage of your sleep ( i.e. You are having a dream and your eyes are moving ) and this signal gets your brain’s attention to the fact that it’s a dream.
This technique has been applied using many devices and gadgets under the general name of lucid dreaming masks.
Some masks detect REM stage by monitoring eye movement while other masks can be simpler.
This simple circuit can induce lucid dream by blinking 2 LEDs periodically to catch the REM stage by chance.
If this happens, you become aware that you are inside a dream and start to control your dream world.
The circuit consists of microcontroller, battery, switch and 2 LEDs.
3Volts coin battery