#aberroscopic grid

• aberoscop - An optical instrument or diagnostic device historically used, or applied in biophysics experiments, for observing, visualizing, and qualitatively assessing spherical and chromatic aberrations of the eye or a lens system. The device typically employs a shaded micrometric grid (aberroscopic grid) through which a light beam passes, allowing the examiner or the patient to directly perceive geometric distortions on the retina or a projection screen.