3.2 Germany

Rodenstock Progressiv R: In the 1970’s Rodenstock was the leader on the German spectacle lens market, which was the principal market in Europe. In their product portfolio they had a progressive lens from BBGR with the name Zoom , which had an optical performance inferior to that of the Varilux 2 design. In Germany Varilux 2 was not only sold by the company Ehinger, the German distributor of Essilor, but also by Rodenstock’s big competitor Carl Zeiss under the brand name Gradal 2.

So Rodenstock decided to develop its own product.

Rudolf Barth (left), Günther Guilino (right) (1982)
Picture: Rudolf Barth (left), Günther Guilino (right) (1982)
Randolf Rodenstock (left),Rudolf Barth (middle),Werner Köppen(right),(1983)
Picture:Randolf Rodenstock (left),Rudolf Barth (middle),Werner Köppen(right),(1983)

Günther Guilino, the Head of the Optical R&D department and Rudolf Barth were responsible for this project. The challenge was to catch up in a few years the advance of Varilux 2 based on a research work of nearly 20 years. Progressive R, the first progressive lens developed in Germany was launched in 1981.

The backbone of the design was an umbilic principal meridian and the horizontal sections perpendicular to the main meridian were so called surfaces with variable periodicity (patent US 4 315 673, filed 1978 in Germany). They provided a platform for a design with large stabilized viewing fields for far and near vision and a moderate level of peripheral astigmatism. The design was symmetric, so that near vision decentration was achieved by a nasal rotation of the lens.

Progressiv R: surfaces of variable periodicity (left) and iso-astigmatism plot

As a new tool to assess the quality of the new design and to develop it iso-astigmatism lines and lines of constant mean power were used. Werner Köppen responsible for Physiological Optics organized the physical-physiological measurements as well as the wearer tests necessary for the optimization of the new lens. Measurement of the visual acuity of Progressiv R wearers confirmed the large viewing zones for far and near vision free of aberrations. In the wearer tests Progressiv R was compared to two competitors’ lenses by more than 100 wearers. Using the double blind methodology the results served to optimize the design and as final control before the launch. With an excellent mark of 2.1 for the global performance and comfort (marking from 1=excellent to 5=poor) Progressiv R was rated superior to the 2 reference lenses. The goal to develop a lens with comfort and adaptation at least equivalent to Varilux 2 was achieved [7],[8].

As concerns the determination of far and near vision power for the Progressiv R lens , the recommendation for the optician was to take the values measured by refraction as customary for single vision and bifocal lenses. This was the marketing argument saying that with Progressiv R the optician works as usual, whereas for Varilux 2 the suggestion common on the German market was that to obtain optimum comfort the refracted far vision power should be changed by -0.25 D and the add power increased by 0.25 D.

Karl-Heinz Pickelmann (1979)

In Germany the Rodenstock Sales department under the responsibility of Karl-Heinz Pickelmann organized a powerful market introduction with a well balanced mix of promotion and scientific presentations by the R&D people. Frank Jaursch, responsible for Export introduced the new product mainly with the help of Rodenstock distributors. The new lens was a big success on the market and for some years Progressiv R was number 2 in the global PPL market share ranking.

The fact that Rodenstock had only a small number of owned subsidiaries outside of Germany was certainly a drawback in the long run for the development of Rodenstock. But in 1980 Rodenstock's turnover was about the same as Essilor's.

Zeiss Gradal HS: The success of Progressiv R on the German market obliged the other big German manufacturer Carl Zeiss to follow with a new proprietary lens in order to upgrade the image of Gradal and to regain lost market share. At that time Bernd Kratzer was Head of the Carl Zeiss Ophthalmic Optics R&D and Wolfgang Grimm responsible for the Product Development.

Bernd Kratzer (left)
Bernd Kratzer (left)
and Wolfgang Grimm (right)
and Wolfgang Grimm (right)

In the patent Hans Lahres, head of the mathematical department and Gerd Fürter, project manager for progressives,  figure as the inventors of the Gradal HS concept, HS standing for horizontal symmetry by an asymmetrical surface structure (patent US 4 606 622, application Germany 1980),see also [9] .This was a clear positioning against Rodenstock’s Progressiv R lens which was a rotated symmetrical design and should have -at least theoretically- less good characteristics for binocular vision. Carl Zeiss presented the “splines” as mathematical solution to break up the surface in tiny area elements allowing to calculate a surface without mathematical constraints. The lens manufacturing was now automated by CNC machines ensuring an excellent precision and reproducibility. Gradal HS was launched by Zeiss in 1984.

At that time Bernd Kratzer was head of the Carl Zeiss Ophthalmic Optics R&D and Wolfgang Grimm responsible for the product development.

Gradal HS: Very small symmetrical distortion by an asymmetrical design (from patent US 4 606 622)

The Gradal HS demonstrated real progress as regards the visual performance of PPLs’ which explains that at the beginning of the nineties it became a reference on the European market.