Patent ID: 6899451

Claim:
An optical system for a Fresnel lens light, said optical system comprising an ellipsoidal reflector ( 10 ), at least one Fresnel lens ( 3 ) arranged at a variable distance (a) from a front edge (E) of said ellipsoidal reflector and a light source ( 2 ) arranged between said ellipsoidal reflector ( 10 ) and said at least one Fresnel lens ( 3 ); wherein said light source ( 2 ) is arranged at a variable distance (b) from a vertex (V) of said elliptical reflector ( 10 ) to propagate a light beam and wherein said distance (b) between the ellipsoidal reflector ( 10 ) and said light source ( 2 ) is changeable to vary an aperture angle of the propagated light beam and said distance (a) is also changeable, but constrained in relation to said distance (b), so that illumination intensity of the propagated light beam is maintained uniform.