View Full Version : Laser Landing Lights

14th Feb 2019, 03:01

Will laser light technology migrate to aircraft in the near future.

They appear smaller than LED, brighter than LED (much brighter) and lower power consumption.

Is there any technical reason why they coundn't be fitted to an aircraft via STC.

14th Feb 2019, 04:11
Maybe. But the characteristics of a laser don't seem to fit well with that of landing lights.

Spatial coherence: Able to focus into a tight beam with minimum spread. But you want some beam spread with landing lights. Both to illuminate an area instead of a point. And to be visible by other aircraft over a wider area.

Narrow spectrum: OK for anti-collision beacons and red/green navigation lights. But landing lights are white. Or at least broad enough spectrum so you can get some return from various different tinted surfaces.

Laser efficiency might have developed beyond that available from other technologies, including LEDs. They might work in much the same way as white LEDs do. A blue or UV LED exciting a phosphor layer to produce white light.

14th Feb 2019, 09:20
Click the link in #1 :ok:

Very impressive and interesting.

14th Feb 2019, 11:35
No concerns about flying towards an aircraft with its landing lights on flying towards you?
I think if the brightness is as quoted (100x) then there are some serious safety issues to address.
Not for the operating crew, who benefit from this new brilliant light, but for all the other crews out there that have to see them fly.

Note: there isa. safety reason why people shining laser lights at aircraft get sentenced and go to prison, how can we enforce that when we use lasers ourselves?

14th Feb 2019, 12:50
One thing to get on record on this Thread is that Laser Spotlights do NOT put out laser beams.

The (multiple) laser beams are shone on a Lens containing (I think) phosphorus. That then becomes fluorescent and produces the ‘beam’.

The points about the high intensity are of course still valid. Cars equipped with them have auto-dipping, difficult on an aircraft.

Check Airman
14th Feb 2019, 14:57
Very interesting. It took some time (15-20 years) for LED technology to become the de facto standard. This may not catch on for a while. Laser lights sound cool though, if nothing else.

14th Feb 2019, 20:42
IIRC, BMW has laser headlights available on some of its models in Europe. With the proper lenses and/or reflectors, they need not be any more dangerous than high-power LED lights.

SMT Member
14th Feb 2019, 21:13
Both BMW and Audi offer laser lights on some of their top-range models, a technology which was developed by Audi for endurance racing in LMP1 prototypes. The main reason for the effort was that they provide better illumination and longer range than xenon or LED lights, as well as allowing for some very fancy features. For example, if they're on 'high beam' and encounter an object, the lights will only be dimmed where they reach the object, while the remaining illuminated area will still be on high-beam.

15th Feb 2019, 09:54
..............For example, if they're on 'high beam' and encounter an object, the lights will only be dimmed where they reach the object, while the remaining illuminated area will still be on high-beam.

Any idea how it does this - by which I mean how does it ‘see’ and ‘know about’ the object? I guess there must be a light sensor in the headlight which detects the backscatter of light reflections from objects, and uses this to modulate the outgoing beam?

15th Feb 2019, 10:33
With the intensity of these things being able to light up a runway for hundreds of meters then the next logical step would be make them swivel so that optimal luminance along the runway can be maintained throughout all phases of take-off/landing preventing bright spots on the ground and/or shining them pointlessly into the sky.

16th Feb 2019, 08:25
Landing lights and car headlights just don't need to be any brighter! They are too intense already. So use the technology to reduce power requirements and increase MTBF while maintaining an appropriate level of brightness. If you're looking at an excessively bright area on the runway, (or road) then the surrounding less-well-lit areas become all but invisible. An appropriate level of illumination allows adequate lighting of the area of concern without blinding oneself or others to an unnecessary degree.

And those blueish car headlights make me want to return the favor with carbon arc searchlights!

Just my personal opinion on the matter.

16th Feb 2019, 21:54
A lot of the problems people have with bright car headlamps are due to after-market High Intensity Discharge lamps which are poorly installed. That's why the UK Government has banned after-market conversions that are problematic ( https://www.gov.uk/government/publications/aftermarket-hid-headlamps/aftermarket-hid-headlamps ). I think we can all be confident that any aircraft or landing lights would not come with problems of after-market bodgers modifying the light pattern to look fashionable. There are also regional variations in lighting design, in particular the UK requires lights to be dipped (so the main illumination has a minimum upper cut-off angle of 0.5 degrees down ) while the USA only requires a horizontal cut-off. This often makes US-specfication lights appear brighter for the same lighting power.

The "Laser" lights are not a laser shining directly onto the road (and therefore into your eyes). Here's a manufacturer's technical description (may contain self-congratulatory prose):
The main point is that they use a blue laser LED to illuminate a "converter" (what I suspect others might call a phosphor, as also used to "convert" UV light to a wide spectrum of visible light in a fluorescent tube) to produce a white light. They reckon that they can get higher lighting power by doing this than by generating the white light in a white LED as at present.

Chu Chu
16th Feb 2019, 23:24
What's the point of having high beams if they don't illuminate objects?

16th Feb 2019, 23:40
Any idea how it does this - by which I mean how does it ‘see’ and ‘know about’ the object?

Using the camera on the windscreen and image recognition algorithms.

16th Feb 2019, 23:42
What's the point of having high beams if they don't illuminate objects?

By "objects", the previous poster meant other cars. You can see them because they carry their own set of lights. :)

17th Feb 2019, 01:51
Good things overdone often become bad things.

Many of these high illumination lighting systems are simply overdone for the purpose they are meant to serve. Just because it's newer and better in some ways doesn't necessarily mean it's better in all respects. I do appreciate that they are more power efficient and last longer though. :ok:

18th Feb 2019, 15:02
Heat dissipation is a major issue in LEDs. Incandescent lights can just radiate it away because the heat transfer at the incandescent filament temperature is good. If you run a white LED junction at high power you have issues with it melting itself, and the maximum temperature is low enough that you have heat transport issues trying to move the heat energy away from the LED before the LED temperature gets too high.

That's why single-LED lights tend not to come in very high power, instead you have to have an array of LEDs. Really high power LED stage lights have large arrays of lights, and if you need a very bright point-like source then a high intensity discharge or specialist filament light is still the way to go.

Therefore greater efficiency in the LED light generation, via such things as these "Laser" lights can up the single-LED lighting power without having to get into arranging, cooling, powering, and focusing an LED array. That leads to some major design advantages even if you are just trying to achieve the equivalent lighting effects of an incandescent Xenon lamp.

Now, if you are trying to use the same power with LED as with incandescent you can get some truly amazing brightness, as in some stage lights that are 8 to 10 times brighter than their incandescent predecessors for the same size package and power consumption. They're a bit nuts.