The latest gizmo to be adopted by top-secret special forces troops fighting the Wars on Stuff is liquid crystal ballistic sunglasses which can change colour automatically much faster than traditional "photochromic" offerings - or at the touch of a button. The US Office of Naval Research says it designed the new Fast-Tint …
And there was me thinking US special ops put their sunglasses _on_ before entering a building with a view to destroying everything inside.
Still, these do sound pretty cool, where do I sign up?
Is this new?
Haven't auto-darkening welding masks been doing this for years? Is this really the first time anyone has thought of doing this in sunglasses, or just the first time the army have tried to use them?
Most of these masks use forms of "reactolite"-like coating
It is not the speed at which the coating darkens (it is nearly instant for some) it is the speed at which it after that returns to transparent. A welding mask must go dark straight away. If it takes it 60s to become fully transparent again - who cares?
For example - you cannot use glasses with a reactolite coating for driving or at least you should not. It is simply too slow lightening up. Moving from blazing Mediteranean sunshine into a tunnel while wearing reactolite is quite fun, especially if the tunnel is not straight. 5-10s driving of half blind are more than to kiss a wall or a pillar at 80mph.
0.5s to lighten up however is a very respectable change time. Definitely enough for driving. I would not mind specs like this once they become available for Joe Average Consumer.
Reactolite coatings aren't fast enough.
LCD masks have been in common use for years. The first one I found on Google was http://www.ashleysdirect.co.uk/solar-powered-lcd-welding-helmet-ce-approved.html - 37 quid. A bit of shopping around will probably find something cheaper - I just wanted a URL to show that these are commonplace items...
It speaks volumes that it's taken so long to get popular consumer technology into Special Forces kit.
Unless there's been some big changes in the last few years the tech of the automatic welding mask is a solar powered LCD.
They instantly darken when the arc is struck, and (almost) instantly lighten when the arc is removed. I suspect the (very short) delay in lightening may be artifical to prevent getting a visual zap when the arc fluctuates during the welding process.
No special coatings, no 60 second lighten up times. See http://www.ashleysdirect.co.uk/solar-powered-lcd-welding-helmet-ce-approved.html for a typical example.
Lol, there speaks someone who has clearly never welded in their life and certainly not with an automatic mask.
PLZT dates from the 1970s
Auto-darkening welding masks came out of research to protect pilots from the flash of nuclear explosions which had started in the early 1970s.
Actually I have done some welding once upon a time
Actually I have done some welding once upon a time. Just not with an automatic mask.
Such exotic items were not available 20 years ago in the Wild East :) In those days the masks there were all with an "always-on" simple tinted glass.
Thanks for enlightening me anyway. We live to learn.
That however does not change what I said regarding glasses. I have yet to see a set of bog standard specs that are LCD changed being sold in my local D&A. If there were I would have bought some :)
Aha, I'd always wondered why glasses developed to shield eyes from the glare of atomic explosions were so slow in their commercial form. So really instant ones would stay black for minutes afterwards perhaps?
If it takes it 60s ... who cares?
I do, because it means I have to wait a minute before I can see where I'm going to put the next three-second weld.
Peril seneitive glasses
They could be a requirement to be worn all the time by all state employees, and automatically be programmed to activate whenever a wikileak is within view :)
would mean that they homed in on light sources, like the sprouting tip of a plant does. Photochromic, meaning that their colouring is light-related, sounds better to me.
Phototropic etc. again.
Oh, I forgot to add: Maybe the word you were really reaching for was "photophobic"?
You mean to say they get in a bad mood when illuminated?
Where do I pre-order?
I doubt that anyone from SpecSavers will read this, but as a thoroughly dissatisfied owner of sloooooooooooooow reactolite glasses that are useless for driving, I would not hesitate to buy these SEAL-specs if they can be made with perscription lenses.
Providing they don't negatively affect the thickness of the lense, they'd definitely be on my buy list.
With my prescription, the reactolite style lenses are way too thick and heavy to be comfortable or stylish (about 3 times thicker and heavier than the lenses I normally get). Something about the reactolite lenses that limits the refractive index of the lens material that can be used.
How are you?
How are you people getting react-to-lights to tint through a car windscreen in the first place? My biggest complaint about them is that they don't do that, necessitating a pair of prescription sunglasses as well as the RTL's.
Opaque when nervous?
Kind of like sticking your head in the sand? I'm guessing you meant translucent...
I'd be more impressed with a faster reaction time; 0.5 seconds is much slower than the blink reflex, so they'll still be dazzled fast changes in brightness. No good having the glasses tinting *after* being exposed to bright light; It'll be even more difficult to see.
Opaque when nervous.
> I'm guessing you meant translucent...
No, he meant opaque.
The trick is to read the paragraph following that one; it mentions the Joo Janta 200 Super-Chromatic Peril Sensitive Sunglasses. Googling for that might mean you understand what everyone else is talking about.
 ...aside from banging the rocks together, that is...
Ever read Douglas Adams?
He came up with the idea of Peril sensitive sunglasses.
"Joo Janta 200 Super-Chromatic Peril Sensitive Sunglasses have been specially designed to help people develop a relaxed attitude to danger. At the first hint of trouble, they turn totally black and thus prevent you from seeing anything that might alarm you."
If we wrap Douglas Adams in copper wire, we could get a current off of him right now...
Methinks someone is not familiar with the Hitchhiker's Guide to the Galaxy.
At last, I've been wanting LCD to darken glasses like this for ages.
I have real issues with taking glasses off to put sunglasses on when driving (can't use reactolite as they don't darken when driving!).
Can we get this on motorcycle helmets, please?
Nothing worse than going into/out of a tunnel and being almost blind for a few seconds, and even the "made for motorcyclists" sunglasses steam up something shocking.
the clue is in the article
made for motorcyclists
Real men don't wear sunglasses, they squint.
I can't get rid of the hilarious mental picture of these cool dudes wearing sunglasses under water.
Better still, cool dude seals wearing sunglasses under water.
Are they available in ...
Versace 4044B Sunglasses?
If not, how about Christian Dior Black Tie 68/S?
"Transition time is less than 0.5 seconds,"
That's far too slow to protect your eyes from a nuclear blast.
Harold Edgerton had the technology for that back in the 1940's, he used it to make a very fast shutter (<1µS) for a camera to photograph nuclear tests milliseconds after detonation.
Awesome pictures, e.g. http://simplethinking.com/home/rapatronic_2.shtml
Welding helmets have to darken in 1/20,000 second to meet CE - they typically take 0.1 - 0.5 seconds to clear.
wow, 2 references to HHG in 1 day in the Reg.
If you're smilin' you ain't panicin'
When you are the president of the galaxy...
...it is imperative to look cool all the time. So what's your excuse for wearing them?
To heck with Zaphod Breeblebox...
...I want to see these glasses on hot babes like Milla Jovovich in 'Ultraviolet'