Patent ID: 7806566

Claim:
A light source unit for use in a projection type video display apparatus having a video display device for modulating light on the basis of a video signal and a projection lens for projecting output light emitted from said video display device upon a screen, comprising: at least two arrayed light sources; and a focusing mirror in the form of a reflector disposed in correspondence with each of said light sources and having a shape of paraboloid or non-spherical form approximating the paraboloid, wherein each light source in the arrayed light sources emits light semi-spherically towards an apex at a center of said focusing mirror; and wherein when D represents an effective diameter of said reflector, f represents a focal distance of said mirror and Z represents a distance between a light emitter of said light source and the apex at the center of said focusing mirror, said light source unit is so constructed as to satisfy 1.6 ×f<D< 3.2 ×f or 1.6 ×Z<D< 3.2 ×Z.