Picture forming device

Abstract

Abstract PURPOSE:To make correction accurately even when magnification conversion is carried out by dislocating a cosine biquadratic rule correction plate from an optical axis. CONSTITUTION:A cosine biquadratic rule which allows the brightness of a projected image to decrease at its circumference is corrected to obtain uniform lightness. For this purpose, a light shielding plate 8 is provided over a lens 7. When magnification is varied, the passing beam area of the lens 7 varies, so the supporting body 20 of the light shielding plate 8 is moved along a cam 21 to vary the distance between the light shielding plate 8 and optical axis X according to the movement of the lens 7, making correction accurately.

Inventors

• 👤 Yoshinori Yasuguro
• 👤 安黒　良則

Bibliographic Details