FIELD: physics.
SUBSTANCE: projection display device includes an image projection unit which projects an image, an operational unit as an operational device whose output value varies according to a stimulus value, a correction value setting unit which changes a trapezoidal distortion correction value according to the output value of the operational unit, and a trapezoidal distortion correction unit which corrects trapezoidal distortion on an image to be projected, according to the trapezoidal distortion correction value. A zero reference position, wherein the trapezoidal distortion correction value is equal to zero, is set in the operating range of the operational unit. The trapezoidal distortion correction value setting unit establishes a dead zone in the operating range such that the dead zone includes the zero reference position and the region surrounding said position, and sets the trapezoidal distortion correction value to zero according to the output value corresponding to location within the dead zone.
EFFECT: enabling adjustment of the trapezoidal distortion correction value to zero without using further indication.
15 cl, 7 dwg
