Dreaming is scientifically thought to occur when Alpha brain waves are dominant and the brain enters a deep state of relaxation or meditative rest. In the early 1960's the Parisian artist Brion Gysin, with the help of his friend the mathematician Ian Sommerville, invented a type of stroboscopic machine, popularly known as the Dreamachine. Designed to be viewed with the eyes closed, it sends pulses of light into the brain that match the rhythm of alpha wave cycles, at a rate between 8-13 hertz, which is about 78 RPM on a turntable.
A low-tech version of the dream machine can be made with a turntable, some opaque cardboard which is fashioned into a rotating cylinder, some glue, and scissors, and a light bulb. Details for building this version are here.