Meditation is entering into a no mind space. No mind can happen in two conditions - When thoughts become zero or when there is one single thought encompassing the whole universe.
In the second situation it is called Brahmakara Vritti.
Even though in Brahmakara Vritti, there is a single thought, there is no subject object relationship. Mind is nothing but consciousness when subject object relationship disappears.
If the mind expands to fill the whole cosmos, then subject object relationship disappears. There is no question of meditator since cosmos encompasses the meditator.
In this situation, what remains is pure consciousness. This is the realization of Virat Purusha - Universal consciousness. What Arjuna experiences in the battle field of Kurukshetra.
This is another way of realizing the Self. Other option is to develop witness consciousness - Sakshi Bhava