Garudapurana 1.235.30

1.235.30

prāpyāvadhikṛtaṃ kālaṃ yāvatsā dhāraṇā smṛtā /
dhyeye saktaṃ mano yasya dhyeyamevānupaśyati //

having reached the designated time—as long as [it lasts], that is considered dhāraṇā.
He whose mind is attached to the object of meditation sees only that object of meditation;