A projection-type display apparatus that has enhanced the sense of being
present by adaptively adjusting, with a simple constitution, projection
illumination, depending on an image signal, without causing color changes
and by increasing apparent contrast. The projection-type display
apparatus includes a light source, a liquid crystal light valve that
modulates light emitted from the light source by turning its light
polarization plane, and a projection lens that projects the light
modulated by the liquid crystal light valve onto a projection surface,
wherein a pivotable light polarizer is arranged between the light source
and the liquid crystal light valve. The black level of an image is
adjusted by adaptively pivoting the light polarizer in response to the
image signal.