Abstract A lamp especially suited for use as a marker light for a motor vehicle, such as a motor vehicle trailer. The light has two lamps, one of which will be automatically turned on when the other fails. The two lamps are located as close together as may be and the lens is so designed that the illumination from the fresnel lens will transmit the required illumination from each lamp. To this end the fresnel lens has serrations on the side of it adjacent the lamps. The serrations are formed by ridges having side edges which are flat. The fresnels are triangular in cross section and the side of all triangle cross sections of the serrations adjacent the center is parallel to a line passing through the center of the lens and through the center of the space between the lamps. The side of all triangular cross sections remote from the center lie in a line lying on the said side remote from the center and passing through the center of curvature of the lens.
A marker light having two lamps, a fresnel lens having fresnel rings on the side thereof adjacent said lamps, said rings being triangular in cross section and having the side of said triangle adjacent to the central axis of the lens lying generally parallel to a line passing through the center of said lens and between said lamps, through the center of curvature of the lens, and the side of said triangle remote from the central axis lying on lines passing through the center of curvature of said lens and through the lens center.
Claim 2
Dependent Claim
94 words
A marker light having two lamps, a fresnel lens having fresnel rings on the side thereof adjacent said lamps, said rings being triangular in cross section and having the side of said triangle adjacent to the central axis of the lens lying generally parallel to a line passing through the center of said lens and between said lamps, through the center of curvature of the lens, and the side of said triangle remote from the central axis lying on lines passing through the center of curvature of said lens and through the lens center.
Claim 3
Dependent Claim
22 words
The marker light recited in claim 1 wherein said triangles have an apex having an included angle of less than thirty degrees.
Claim 4
Dependent Claim
49 words
The marker light recited in claim 1 wherein the side of said triangle adjacent the first mentioned side is always disposed at right angles to a tangent to the lens base at the point where a line lying in the said side passes through the face of the lens.
Claim 5
Dependent Claim
28 words
The marker light recited in claim 1 wherein the centraL portion of said lens over approximately a 30* arc is solid and has no said fresnel rings therein.