An optical system contains a thin lens, n = 1.4, with positive curvature of radius R, = 25 cm for surface 1 and negative curvature of radius R2 = -25cm for surface 2. This lens collects light from the right side. To the left of the lens we want to keep a flat plate of thickness t of the same glass so that the light that radiates from a distant object is focused on a screen 35cm to the left of the lens. What is thickness t (in cm) ?

An optical system contains a thin lens, n = 1.4, with positive curvature of radius R, = 25 cm for surface 1 and negative curvature of radius R2 = -25cm for surface 2. This lens collects light from the right side. To the left of the lens we want to keep a flat plate of thickness t of the same glass so that the light that radiates from a distant object is focused on a screen 35cm to the left of the lens. What is thickness t (in cm) ?