Optical configuration for projection television apparatus

A projection television apparatus comprising:

• three cathode ray tubes for emitting red, green and blue images respectively and which are placed with their optical axes in a single plane at 90.degree. to each other with the faceplates thereof adjacent each other to define a rectangular parallelepiped shaped space;
• two dichroic mirrors in said space with the surfaces facing said faceplates of said tubes and in an X shaped configuration when viewed from the edges of said mirrors, each mirror reflecting a different color than the other mirror, at least one of said dichroic mirrors consisting of two small dichroic mirror parts which are separated at the line of intersection where said two dichroic mirrors cross each other, each small dichroic mirror part having a single transmission characteristic which is different from the same single transmission characteristic of the other small dichroic mirror part for minimizing the difference in brightness ratios of the respective colors transmitted;
• and
• a lens on the opposite side of said space and positioned on the optical axis of the center tube of said three tubes.