Newton’s Ring Apparatus
Comprising a small wooden frame of size 5”x3”x3” with a matt blackened inside and provided with a glass plate 4” x 3” x 1/8 0 mm mounted at an angle of 45to reflect the light downwards on to a Planoconvex lens of 50mm diameter having 100 cm focal length which rests on a plain glass plate 3” x 3” x 3/8 on the base of the box.