A projection type display device capable of satisfactorily correcting the luminance unevenness and color unevenness caused in the image display surface of the screen 5, the light source 1 and the light valve 2 and the illumination optical system 4 and the projection optical system It has a 5, the illumination optical system 4, and the light intensity equalizing element 41, a first optical system for deriving a light beam on the image-forming area (2a) of the light valve 2 (42, 43), the opening including a regulation member 6, the aperture regulation member 6, a plurality of screen (5) and optically disposed in a position that is not in conjugate relation, also, the image forming area (2a) or the screen 5 of the using a measured value or a calculated value of the relative roughness of the partition, the relative illumination is provided at a position corresponding to the lower partition, closing light-shielding portion, and the notch area of ​​the opening extension portion to widen the opening, the relative illuminance is high partition It is provided in a position corresponding to, broadening the light-shielding portion, and has at least one of a reduction projection of the opening to narrow the opening portion.