A projection type display device comprising: a light source; reflection type liquid crystal display devices (1r, 1b, 1g) allowing an incidence of an illumination light from the light source through a wire-grid type polarization beam splitter for polarizing the illumination light; and an imaging lens system for providing an image from a modulated light which has been polarized, modulated and reflected by the reflection type liquid crystal display devices (1r, 1b, 1g) and subsequently diverged from an optical path for the light source by the wire-grid type polarization beam splitter, wherein the reflection type liquid crystal display devices (1r, 1b, 1g) including a first transparent substrate having a transparent electrode formed therein and allowing an incidence of the illumination light, a second substrate opposed parallel to the first substrate through a gap and having reflecting electrodes and drive circuits arranged in matrix for every pixel thereby to reflect the illumination light transmitted through the first substrate and emit the illumination light therethrough and a liquid crystal layer enclosed between the first substrate and the second substrate to polarize and modulate the illumination light transmitted through the first substrate and also composed of nematic liquid crystal whose dielectric anisotropy is negative, the wire-grid type polarization beam splitter is arranged so as to have its polarization spectroscopic surface inclined to the first substrate of the reflection type liquid crystal display device, the wire-grid type polarization beam splitter also having wire grids formed on the polarization spectroscopic surface and also arranged parallel to the first substrate, each of the reflection type liquid crystal display devices (1r, 1b, 1g) is either: a first twist type liquid crystal display device where, in view from the first substrate, liquid crystal molecules on the side of the second substrate are aligned in the clockwise direction with respect to a predetermined reference line and liquid crystal molecules on the side of the first substrate are aligned in the counterclockwise direction with respect to the predetermined reference line; or a second twist type liquid crystal display device where, in view from the first substrate, liquid crystal molecules on the side of the second substrate are aligned in the counterclockwise direction with respect to a predetermined reference line and liquid crystal molecules on the side of the first substrate are aligned in the clockwise direction with respect to the predetermined reference line, characterized in that assuming one of directions of projection lines obtained by projecting the wire grids on the second substrate vertically, the one direction being directed to a direction where one extension surface of the polarization spectroscopic surface intersects with another extension surface of the second substrate when the one direction is turned in the counterclockwise direction by 90°, is represented by X-axis; the first twist type liquid crystal display device has its reference line's vector disposed within a range (φ) of 225°±10° in the counterclockwise direction from the direction of X-axis, in view from the first substrate, and the second twist type liquid crystal display device has its reference line's vector disposed within a range (φ) of 315°±10° in the counterclockwise direction from the direction of X-axis, in view from the first substrate. a light source; reflection type liquid crystal display devices (1r, 1b, 1g) allowing an incidence of an illumination light from the light source through a wire-grid type polarization beam splitter for polarizing the illumination light; and an imaging lens system for providing an image from a modulated light which has been polarized, modulated and reflected by the reflection type liquid crystal display devices (1r, 1b, 1g) and subsequently diverged from an optical path for the light source by the wire-grid type polarization beam splitter, wherein a first twist type liquid crystal display device where, in view from the first substrate, liquid crystal molecules on the side of the second substrate are aligned in the clockwise direction with respect to a predetermined reference line and liquid crystal molecules on the side of the first substrate are aligned in the counterclockwise direction with respect to the predetermined reference line; or a second twist type liquid crystal display device where, in view from the first substrate, liquid crystal molecules on the side of the second substrate are aligned in the counterclockwise direction with respect to a predetermined reference line and liquid crystal molecules on the side of the first substrate are aligned in the clockwise direction with respect to the predetermined reference line, assuming one of directions of projection lines obtained by projecting the wire grids on the second substrate vertically, the one direction being directed to a direction where one extension surface of the polarization spectroscopic surface intersects with another extension surface of the second substrate when the one direction is turned in the counterclockwise direction by 90°, is represented by X-axis;