Whether a tool designed for cave diving or an elegant evening accessory, a watch that’s legible in low light will always win the day. We shine a light on the history of the luminous dial and explore five luxury watches deploying the latest luminescent technology.
Telling the time at all hours is something we take for granted these days, thanks to our digital devices. But long before any of these electricity-reliant inventions, doing so with ease was possible only in daylight hours. Unless there was a bright moon, accurate timekeeping at night with a pocket watch or an early wristwatch required a light source such as a lamp or candle. A minor annoyance when at home, but downright dangerous on a First World War battlefield.
Out of the dark: the origins of lume
As with so many of the developments undergone by the wristwatch, it was the Great War that supercharged its innovation – in this case, the operational need for a timepiece that would be readable in the dark without giving the game away. Lives depended on it. It was during this period that radioactive material radium began to be painted onto watch dials. The practice continued until 1968, when it was banned outright for obvious health reasons.
Since that time, watchmakers have tested, developed and released a range of luminescent dials, hands and hour markers for military, professional and dress watches that deliver a glow without any of the troubling side-effects. Japanese businessman Kenzo Nemoto was integral to their success. He started his luminous-paint business in 1941 and was initially commissioned to equip Japan’s submarines and aircraft with legible glowing depth meters and cockpit dials.
Having witnessed the effects of radiation in his home country at the close of the Second World War, Nemoto went on to focus his efforts on producing a safe, non-radioactive product, using new phosphorescent-pigment technology. The entrepreneur’s vision was finally realised in 1993, in the shape of a new solution using strontium aluminate.
The future is bright: the luminescent dial today
Incredibly, unlike other phosphors, strontium aluminate, or LumiNova®, does not require an energy source to work its magic. It simply needs exposure to natural or artificial light, which rapidly energises its electrons, creating a glow that will diminish in intensity after several hours.
Following a re-brand to Super-LumiNova® and buy-in from the Swiss watchmaking industry in 1998, it was this ingenious technology that was widely adopted by most luxury watch brands. The likes of Rolex and Seiko produce a similar product in-house for their luminous-dial offering.
Today, this luminescent technology is an increasingly standard element of watch design, with Super-LumiNova® being deployed across bezels, hands, minute markers and date windows – and not only on tool watches, but on dress watches too. We’ve selected a range of examples below to highlight both the practicality and the beauty of the luminous dial.
Pioneering spirit: Rolex Explorer II
A timepiece that’s evolved from Rolex’s deep involvement with exploration, the 42mm Rolex Explorer II in Oystersteel (£6,650) is a serious professional tool watch. It’s proved itself in the world’s most punishing environments, but it can equally be worn as a statement piece in more familiar surroundings. Featuring a date window, an additional orange 24-hour hand and a fixed bezel with 24-hour graduations to help distinguish day from night, it comes in a distinctive white- or black-dial configuration. Both are adorned with 18-carat gold hour markers and fitted with a highly legible Chromalight display with long-lasting blue luminescence.
Space race: OMEGA Speedmaster Moonwatch
Endorsed by NASA as the first watch on the Moon, and part of all six lunar missions, the Speedmaster collection has real gravitas. The OMEGA Speedmaster Professional Chronograph has a unique place in the history of space exploration as the only piece of equipment used in all of NASA’s piloted space missions from Gemini to the current International Space Station program. Finding the perfect balance between function and form, this Omega Speedmaster Professional Moonwatch features a black 42mm stainless steel case and a black bezel complete with tachymeter scale. The dial plays host to a small seconds sub-dial, a 30-minute recorder, a 12-hour recorder and a central chronograph hand, all protected by a hesalite crystal. With a stainless steel bracelet and water resistant to 50 meters, this confident watch is powered by calibre 1861 manual-winding chronograph movement.
Battle ready: Bremont Broadsword
It’s appropriate to include the 40mm satin and polished two-piece hardened stainless-steel Bremont Broadsword (£2,595) in our roundup of modern luminescent timepieces, since Bremont is the first watch brand to have signed up to the United Kingdom Armed Forces Covenant. This means it’s the sole horology house allowed to use the signs, symbols and insignia of the army, navy and air force on its watches – which is fitting, given luminous dials’ military heritage. The robust Broadsword was inspired by the iconic ‘Dirty Dozen’ models of the Second World War. Set against a black metal dial, the custom mint-coloured Super-LumiNova® on the matt black hands really catches the eye. A trusted military-grade companion for telling the time under the cover of darkness.
Time immemorial: the Longines Conquest Heritage
The sophisticated Longines Conquest Heritage 35mm (£920) is proof that not all timepieces with luminous dials fall into the professional- or tool-watch category. A timeless classic in stainless steel with a silver-toned sunray dial, it has a date window at 12 o’clock and contrasting gold-tone gilt hands and hour markers filled with Super-LumiNova®. Powered by a reliable automatic movement, it offers high performance, too – it’s water-resistant to 30m, has a screw-down case back and screw-in crown, and offers a 38-hour power reserve. We love both the form and function of this handsome dress watch.
Out of this world: the Breitling Galactic 29
The Breitling Galactic 29mm (£3,810) combines traditional and contemporary aesthetics with feminine elegance. Driven by a highly reliable SuperQuartz™ automatic movement, this ladies’ watch is not only attractive, but also boasts cutting-edge technology. Its elegant mother-of-pearl dial is studded with diamonds and features a date window at 3 o’clock. Polished-steel hands filled with Super-LumiNova® make for an easily legible dial, even in low-light settings, providing extra peace of mind for those who require precision and performance at all times from their wristwatch.