The phoropter is remote controlled so the optometrist does not have to be physically near the patient as they do the subjective vision test. This basically fine tunes the objective test, the familiar questions of "Which is better A or B?" Everyone sees differently and everyone wants to have their own unique vision. The autorefractor prints out the measurement of each eye independently, the subjective exam accommodates for usage, custom, and difference in acuity between the two eyes.