Patent ID: 8109642

Claim:
A projection type image display apparatus A projection type image display apparatus comprising: a light source; an optical integrator for changing distribution of illumination of light outgoing from the light source; a color separation optical system for separating the light outgoing from the optical integrator into a plurality of light beams; and a relay optical system including a plurality of relay lenses and reflection mirrors for relaying the light beams separated by the color separation optical system; wherein the relay optical system includes means for adjusting an inclination angle of at least one of the plurality of relay lenses with respect to an optical axis of illumination of the light outgoing from the light source; wherein the relay optical system includes a first relay lens that receives the light from the light source, a reflection mirror that reflects light passing through the first relay lens, and a second relay lens that receives light from the reflection mirror; wherein an optical axis direction of the light directed toward the first relay lens from the light source defines a Z-axis; wherein an optical axis direction of the light directed toward the second relay lens from the reflection mirror defines a X-axis; wherein a direction perpendicular to both the Z-axis and the X-axis defines a Y-axis; wherein the angle adjusting means includes a holding member that holds the first relay lens, a base body that supports the holding member, and a fixation member that fixes the holding member and the base body to each other; wherein an upper portion of the base body defines a surface substantially parallel to the Z-axis and the X-axis; wherein that surface of the upper portion of the base body, which is brought into contact with the holding member, defines a spherical surface; wherein the upper portion of the base body includes an opening extending in the Z-axis direction; wherein a fixation hole, into which the fixation member enters, is provided on that side of the holding member, which is brought into contact with the upper portion of the base body; wherein the fixation member is passed through the fixation hole from the opening to fix the holding member to the base body; wherein the holding member is turnable along the opening in the Z-axis direction to change an angle of the first relay lens about the X-axis; and wherein the holding member is turnable about the fixation member to change an angle about the Y-axis.