It just keeps shining and shining and shining…

“It just keeps going and going and going…” was a slogan used by Volkswagen back in the 60s and 70s to advertise the endurance of the immensely successful Beetle. Just like Volkswagen, LIMO puts a lot of emphasis on reliable, fault-free and highly durable technology: measurements have shown that an average laser module in the power class of up to 50 W has an operating lifespan of up to 150,000 hours.

In 2008 the press reported an endurance record: a globetrotter from Germany had travelled more than 300,000 kilometres in a VW Beetle. The owner, a mechanical engineer, had spent an estimated 10,000 hours driving over dusty desert tracks, serpentine mountain roads and muddy jungle paths.

"Shining endurance experts": measurements taken of a LIMO laser module in the power category of up to 50W show an extremely long lifespan of up to 150,000 hours (almost 17 years) / Image source: LIMO

“Shining endurance experts”: measurements taken of a LIMO laser module in the power category of up to 50W show an extremely long lifespan of up to 150,000 hours (almost 17 years) / Image source: LIMO

The applications for the LIMO Lissotschenko Mikrooptik GmbH are much less adventuresome, however they also last much longer. “We regularly test the life expectancy of our standard laser modules”, says Dr. Jens Meinschien, Head of Research and Development at LIMO. “And we often have wonderfully surprising results.” Testing and evaluation methods used to describe, evaluate and predict long-term laser use based on the international norm ISO 17526 show lifespans that are sometimes well in excess of 100,000 h.

One 32 W laser of the type HLU32F400-880 has been undergoing a tough endurance test since February 2009, with LIMO measuring the optical output every hour. In that entire period, the optical output has declined by a mere 6.7%. A similar test was carried out with a LIMO50-F100-DL980 which was checked every half hour for two full years: a 100 µm fibre had an optical output of 50 W and this decreased by a mere 1.7% over the course of the test. Based on ISO 17526, these two tests lead to an expected lifespan of 130,000 and 140,000 h.

LIMO also took a close look at their pilot lasers (for those who are new to the field: a pilot laser is a low power laser that sends out a kind of targeting or guiding beam of visible light parallel to the invisible main laser). Measurements taken of pilot lasers (output 5.0 mW, wavelength 532 nm) after more than 3 years of continuous use show a life expectancy of 100,000 h.

All in all: the laser modules in the output category of up to 50 W show an expected life span of 100,000 to 150,000 h. These measurements were taken from standard laser modules, none of which had received any kind of “special, lifespan extending” treatment. Dr. Meinschien: “Our test results are realistic because we ran the lasers under normal conditions and in real time. Nor did we artificially age them – for example through hard-pulse operation or thermal stress.” Find out about the many applications that these “endurance experts” are suited for at the International Congress on Applications of Lasers & Electro-Optics (ICALEO) in San Diego, California (19th to 23rd of Oct., 2014) or at the Glasstec in Düsseldorf (21st to 24th of Oct., 2014, Hall 11, Booth 11A07 ).