Soviet lens with the name Helios performed on a Planar (Planar) Dr. Rudolf (Paul Rudolph, 1896, Germany). Rudolph himself is not fully evaluated the possibility of his scheme. They were discovered in English optician H. Lee (Horace W. Lee), developed in 1920 lens "OPIC» (Opic, the company, "Taylor-Hobson» - Taylor & Hobson), who had a high aperture ratio - 1:2.5 (rather than 1:3.3 at the "Planar") at an angle of 50 degrees. Further Soviet lens of this scheme were issued under different names by many firms.