Pioneers in organic filters

Pioneers in organic filters

Multilens’s founder Lars Hellström often said that creative optometrists find solutions, while others sell glasses. On good grounds, he was called the “Gyro Gearloose of optics” by his first customers and began experimenting with filters early on.

The pioneer

As early as the 1970s, the company Corning manufactured coloured filters in mineral glass, but there were some challenges with them. First of all, the material was quite expensive. At this point, filters could be added to glass with powers, but the range was limited and filters could not be combined with special optics. When Lars Hellström started Multilens in 1983, he, therefore, wanted to test whether it was possible to colour plastic material. And after a period of trial and error, it worked – Lars Hellström became the first in the world with filters in plastic material!

– Dad’s little business was located in an old paper mill, in the home of the former factory caretaker. That’s where he started testing different pigments. He had a small hob and pots with colouring mixture and dipped the plastic lenses until he found the right colours, says his son Björn Hellström.

Lars Hellström who founded Multilens.

The sons Björn, Martin and Ola Hellström who today manage Multilens.

New filter colours

First out were ML511, ML527 and ML550. They cut off the same light as Corning’s versions, but since then Multilens has developed a wide range of own filter colours, such as ML450, ML500, ML585, and C1. Several of them were so successful that attempts have been made to copy them – not least the popular C1 filter that is often used for sunglasses.

Many attempts have been made to copy the ML Filter

– Our first filters effectively absorbed all unwanted light, but users sometimes experienced that the colour vision changed too much. That’s why we developed the C1 filter, which retains colour vision better and feels a little softer, says Björn.

– We worked together with an optician named Carl Otto Ahlström and first the filter was called CO1 after him, but when more optometrists became involved in the development, we simplified the name to C1, which also stands for Comfort.

Contrast, comfort, protection

In the early days of filters, most people talked about contrast-enhancing properties. Today, the message is more about comfort and the patient’s own experience. But filters also provide protection and that is why the ML400 was invented.

– It is usually said that UV light ends at about 400 nm and therefore we wanted to cut the light there, says Björn. This was simply our way of UV-treating the glass – we put on a light 400-colour for protection, with a small dose of comfort.

So where is the filter technology

going now?

– I think we will see more broken filter colours, ie filters that select the light, but with a small amount of grey or brown colour for a more aesthetic effect. I also think we will see more variants of filters for people with neuro-visual problems. And we will continue to explore how filters in different ways can make us feel better!

Published 2 july 2023