1951 - sunlamp (blended) 1952 - sun- and heatlamp 1952 - sunlamp (blended) 1952 - sunlamp (carbon arc) 1953 - sunlamp (blended) 1953 - sunlamp (mercury) 1953 - sun- and heatlamp 1954 - sun- and heatlamp 1954 - sun- and heatlamp 1955 - heatlamp (incandescent) 1956 - sun- and heatlamp 1957 - sun- and heatlamp 1958 - sun- and heatlamp 1958 - sunlamp (blended) 1958 - heatlamp (incandescent) 1958 - heatlamp (incandescent) 1959 - sun- and heatlamp 1959 - sun- and heatlamp