Patent ID: 7352119

Claim:
A projector lamp assembly comprising: a double ended high intensity arc discharge lamp burner having an axis and a body defining a vessel with an enclosed volume and an axially aligned first electrode and second electrode each electrode having an internal tip, the first electrode tip and second electrode tip having a separation distance of g and having a midpoint axially between the tips and an axial distance from the midpoint to an end of the body of L; an reflector having a reflective surface in the form of a portion of an ellipsoid of revolution with an eccentricity of e 0 , a major semiaxis distance of a, a minor semiaxis of b, a first focal point F 1 and a second focal point F 2 , the first focal point F 1 and the second focal point F 2 being axially aligned with the lamp with the first focal point F 1 being positioned at the midpoint of the lamp; and an optical transmission structure having an optical input positioned relative to the reflector to locate the input at the second focal point F 2 , the optical transmission structure having an etendue of E and an acceptance angle of γ′; wherein e 0 =e a (γ′)−Δ e (γ′, E,g ) equation 3 e a = 2 + 1 - tan ⁢ ⁢ γ ′ 2 2 + 1 + tan ⁢ ⁢ γ ′ 2 equation ⁢ ⁢ 1 and Δ ⁢ ⁢ e = 1.3 ⁢ ⁢ sin ⁢ ⁢ 2 ⁢ ⁢ γ ′ ⁢ ⁢ exp ( - 2 ⁢ E 0.17 g ) . equation ⁢ ⁢ 2