Danish lighting companies Louis Poulsen, Lyfa and Nordisk Solar Compagni have all produced lamps with a very similar shape. The Poulsen version is included in a 1967 catalogue but certainly dates from earlier than that. Entitled Emaillearmatur, it comes in four diameters (30cm, 35cm, 40cm and 45cm), and one colour (black, pictured below). No designer is specified.

Louis Poulsen Emaillearmatur

In 1968 the Lyfa design appears, made of glass and credited to the architect couple Eva & Nils Koppel. With a diameter of 29cm, it was produced in two colours – a yellow version (below) entitled Gultop (in English, yellow top) and a green one called Grøntop (green top), winning an iF Product Design Award in 1969 under the collective title Glastop.

Lyfa Eva Nils Koppel Glastop Gultop

The first time we come across the Nordisk Solar version (below) is in a catalogue from the late 1970s or early 80s. Its title is Solo and its diameter is 35cm. No designer is given.

Nordisk Solar Compagni Solo

Much later, perhaps the early 80s, Lyfa produced another lamp in the same style, this time in metal, but we have no formal record for that.