The Petzl Nao

The company said the NAO features two LED beams that automatically adjust depending on what the user is doing, with minimal manual adjustment.

The 187g unit features a lithium ion rechargeable battery with an integrated USB connector which means it can be charged through a laptop or other equipment with a USB socket.

Petzl said the NAO’s battery life can be extended significantly due to the Reactive Lighting system. Its optional extra belt kit is also available to reduce the weight on the head and keep the battery warmer in cold conditions.

The headtorch features a focused LED and a wide-angle LED, which both sit below a light sensor which is at the heart of the system.

The company, with a long heritage in producing headtorches, said “A built-in light sensor adapts the headlamp’s beam pattern and light output instantly and automatically to suit the user’s needs.

“This means the user gets an ideal amount of light with minimal manual adjustment required. This self-adjusting lighting mode also results in longer burn times, due to more efficient use of the rechargeable battery.

“The shape of the beam and the power of the headlamp instantly adapt to the need – lighting for close, medium or long-range vision – so the user always has the right amount of light.

“The headlamp automatically adapts to changes in surrounding light conditions, allowing the user to remain focused on the activity at hand without worrying about adjusting the headlamp.”

The automated system can be overridden to give full power constantly when needed, though Petzl said this is likely to reduce battery charge length.

Petzl added: “One of the big problems with today’s head torches is the relationship between high-performance LED power consumption and battery capacity. The choices are limited; either unregulated light, giving rapidly diminishing light output, or regulated output where maximum power is only available for relatively short periods.

“Petzl’s Reactive Lighting technology allows your battery to optimise its output, only providing the power you need for the environment you are operating in.The result is that battery life can last at least three times longer than it would do under constant full power.”

The NAO has three automated modes:

For proximity lighting, when looking at an object at close range, for example when reading a map, tying a knot or setting up a tent, the beam is very wide and less powerful. Lighting adjusts automatically to the distance of the object

For mobility, when walking or running for instance, the beam is wide and has medium strength in order to illuminate obstacles in the path

For distance vision, when raising the head to see into the distance, looking for a trail marker or an anchor on a climb, for example, the light output increases and becomes more focused.

The Petzl NAO features a front headset with twin LEDS and sensor, linked to the rear-mounted battery by the new Zephyr cord-lock headband.

The battery is a 2300 mAh lithium-ion unit, rechargeable via its integrated USB plug. There is a belt kit version for the battery, plus a detachable top strap for additional stability when running.

Lighting is controlled via a large rotating on/off switch, which can be locked in the ‘off’ position. The switch allows the user to choose between Reactive Lighting or Static modes, with high/low output options in each. Static lighting gives a fixed output – non-reactive.

In Reactive Lighting mode the headset uses a single high-output LED in a wide-angled beam. In Static mode the headset uses both the wide-angled beam and a second high-output LED configured for a focused beam. Maximum power output is 355 lumens. Performance profiles can be customised via Petzl’s OS 2.0 on computers.

For ‘emergency use’, the battery pack will accept 2 x conventional AAA batteries.

The NAO is not expected in UK shops until July this year and is expected to have a typical selling price of £135.

More details are on the Petzl website.