Adjustable Sun Glasses Regulate Light (Sep, 1940)
Adjustable Sun Glasses Regulate Light
Sun glasses recently introduced can be adjusted by the wearer to admit more or less light, according to the brightness of the sun and its reflected glare. The sun spectacles utilize special light-polarizing glass (P.S.M., April ’36, p. 20). Each eye of the wearer looks out through two special lenses. The lens nearest the eye is stationary, while the front lens can be rotated by pushing a small button on the bridge of the spectacle frame. When the button is moved to the extreme left, the maximum amount of light reaches the eyes, but as it is pushed back toward the right, light penetrating the lenses is cut down until they are so dark that the brightest possible beach scene may be viewed without discomfort. Special louvered plastic side shields block out annoying reflections.