In a projection type display apparatus including a blue CRT display
apparatus with low luminous efficiency and low luminous efficiency, the
present invention seeks to improve contrast while suppressing the fall in
brightness for red, green, and blue color as a whole. In the projection
type display apparatus, the images of three colors outputted from three
monochrome CRT display apparatuses 10R, 10G, 10B which respectively
output monochromatic video signals of red, green, and blue color, are
respectively projected on a screen unit 14 via a reflecting mirror 12 so
as to synthesize a image of three colors and generate a color image. The
brightness of the green CRT display apparatus which outputs the green
image having the highest luminous efficiency is increased, while
maintaining the brightness of the blue CRT display apparatus 10B.
Further, a light absorption means for tinting to reduce the increased
green brightness is provided to balance the whole brightness of red,
green, and blue. Contrast is improved by the light absorption means for
tinting. Preferably, the red CRT display apparatus 10R is treated
similarly to the green CRT display apparatus 10G.