Beauty in darkness

"Lumen"

"LUMEN" is science's answer to design in watchmaking. The series of "Lumen" watches by Lange offers luminous displays of date, time and even the inner beauty of a Lange movement.

The light source that charges the luminous displays in the "Lumen" timepieces is made possible by the sapphire-crystal dial of the timepieces, which has a patented semi-transparent coating that's permeable for ultraviolet light.

"The transmission of light waves in the visible spectrum is reduced to obtain a high-contrast, easily legible dial," Lange says.

"At the same time, it allows light in the UV range to pass through."

This enables the dial to radiate the previously absorbed light energy and glow in the dark.

All it takes is about 90 minutes of direct sunlight or blue-white artificial light to completely activate the luminous substance, according to the brand.

The first "Lumen" watch is the Zeitwerk "Luminous" (limited 100) rolled out in 2010.

It has a dial with patented semi-transparent coating and a jumping numerals display with luminous lining.

This means the exciting sequence in time measurement executed by the watch can also be observed in the dark.

In 2013, the Grand Lange 1 "Lumen" (limited 200) made its appearance as the first model with a glowing outsize date.

Next up, in 2016, was the Grand Lange 1 Moon Phase "Lumen" (limited 200) that offers both a luminous outsize date and a moon-phase display.

The Datograph Up/Down "Lumen" (limited 200), which came in 2018, is the first Lange chronograph where all visible functions on the dial are luminous.

All these early "Lumen" timepieces were launched in a limited edition with a platinum case, except for the Zeitwerk Honeygold "Lumen" (limited 200) which comes in a Honeygold case.