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Laser Fire Exit Pointer

Go That-a-way!
  [vote for,

Fire exit signs sometimes are obscured by smoke from a fire, particularly in a low-ceiling area which traps the smoke near the same level as the exit signs.

The Laser Fire Exit Pointer mounts in the ceiling, and consists of a laser pointer facing a rotating diagonally mounted mirror. Normally "off", the system is activated as part of the fire alarms. As the mirror rotates, the point of light appears on the floor, and travels in the direction exiting persons should use. Each unit indicates direction for a small area; a large number of these units can be used to cover large areas or complicated routes.

If there is smoke in the air, the visibility of the system actually improves: the laser beam is visible in the smoke.

In an enhanced system, the orientation of the individual units can be altered so as to direct traffic away from the actual location of the problem.

If your alarm system is multi-purpose (fire, tornado, hazmat, etc.) - people can get confused by different siren signals. This system gives an additional hint for the frightened or forgetful: if the dots are just sitting there, stay put. If they're moving, follow 'em.

lurch, Mar 10 2003

System Sensor, Inc. http://www.systemsensor.com/
Industry-dominant smoke-alarm manufacturer of networked detectors. Based in St. Charles, Il [RayfordSteele, Oct 05 2004, last modified Oct 21 2004]

product http://www.laserlyte.com/
See the product link to "SafeEscape" on the above link [cevilthedevil, Oct 05 2004, last modified Oct 21 2004]

Laser Aid http://www.laseraid.ca/laser_aid.htm
Coming soon to a burning building near you. Where DO people come up with these things? [Shz, Aug 14 2006]


       Complicated, but possible. Perhaps the different alarm sounds translate to different colored light as well. (+)
Shz, Mar 10 2003

       I think I described it badly. If you ignore the "enhanced" version for a moment, each unit consists of a laser pointer, a motor, a mirror, two AA batteries and a switch. Simple - darn near primitive - and, in quantity, pretty cheap, too.
lurch, Mar 11 2003

       It would drive cats crazy ..... heh, heh.....
8th of 7, Mar 11 2003

       How powerful would the laser have to be to be seen through smoke? Conventional laser pointers can look pretty dim and weedy in certain conditions. And you wouldn't want your laser exit pointer to be starting fires.
pottedstu, Mar 11 2003

       I've got a selection of lasers of varying power, and a smoke machine. I'll give this a test the next chance I get, but a Class III laser should be intense enough to work over a 20 metre range even in dense smoke, and if it's scanning, the exposure risk is greatly reduced.
8th of 7, Mar 11 2003

       Could be easily integrated into the smoke alarm. Also one of my previous jobs. Worth a patent, I think.
RayfordSteele, Mar 11 2003

       //Simple - darn near primitive//   

       I overcomplicated it by thinking of beam splitters, mirrors, and disco balls connected to alarm systems.
Shz, Mar 11 2003

       Disco Stu says 'Hey, I'm thrusting in the direction of the nearest exit, baby.'
sambwiches, Mar 11 2003

       Downside: when the next nightclub disaster happens, they'll all think it's simply part of the light show.
RayfordSteele, Mar 11 2003

       //But what do the cats do when the alarm goes off?//   

       They run into the wall repeatedly.
Shz, Mar 11 2003

       If you've designed it correctly, the cat can chase dots all the way to the exit. At which point, running out of dots, the cat turns and scurries back inside - disrupting traffic, getting trampled & toasted...
lurch, Mar 11 2003

       If you design it to be mounted low insead of high you may avoid power issues (laser not making it far enough through the smoke). You'd have to have a wire up to a smoke detector though. + either way, great idea.
Worldgineer, Mar 11 2003

       Hey, not only this as a great idea, but why not take existing technology and instead of a dot, make it an arrow with the word EXIT in it (Red arrow, Green exit for visibility, I think.. but that's getting complicated again).   

       The tech to make patterns is realitivly cheap by now, one should think.   

       I agree with RayfordSteele: Worth a patent.
JackandJohn, Mar 11 2003

       I don't think I'd mount it that low. Too likely to shine in someone's eyes. I do like the fact that the arrow is on the ground; helps visibility if the smoke is heavy enough to crawl out.   

       Alternatively, if you don't want to bother with the patent approach, contact the people at my link. My employer for an internship.
RayfordSteele, Mar 11 2003

       //Too likely to shine in someone's eyes.// Well you wouldn't point it up. On the floor. . . . . .
Worldgineer, Mar 11 2003

       I have heard this before and do not agree that this idea would work in a large building and in thick smoke. I do not think a low wattage laser will penetrate through 20m thick smoke.   

       It may work in a domestic situation, where you will never be more than a couple of meters from the exit. In any case it has been already baked, right down to the flashing arrows moving along the floor, so a patent would be difficult (see link)
cevilthedevil, May 07 2003

       It was never intended to reach through 20 meters of thick smoke. The intention was that a small, cheap unit could be placed every so often - perhaps one in each fluorescent light fixture - and would provide better visibility than a single diffuse green blob exit light at the end of a hallway.   

       Personally, I would not go for the arrows on a full-baked design, but this being the halfbakery and all - it might be ok to have the ones in front of the elevator do a laser show while you're waiting for the next car.
lurch, May 07 2003

       //while you're waiting for the next car// Please don't take an elevator when there is a fire. And definately don't wait for the next car.
Worldgineer, May 07 2003

       Wouldn't spelling those instructions be appropriate for the laser show?
lurch, May 07 2003

       Why bother spelling? I'm picturing an animation of the wacky adventures of a cartoon rabit and what happens to him in the elevator.
Worldgineer, May 07 2003

       Notes from one of the product designers:   

       First - let me say that the general idea was NOT mine - so I accept neither credit nor blame, but as the technical lead on this project, I can give you some insights as to the product's design trade-offs.   

       General Idea: It was supposed that the Laser sources in this would perform the job of indicating an exit better than other light sources - This is the kind of thinking that one might expect from the owners of a laser pointer company. Other sources, mounted lower are a better idea - but this one sells lasers. See?   

       Design Implementation: The design itself is actually quite slick. It can be mounted so that it projects a sequence of arrows from nearly any direction toward the wall its attached to. There is a very cheap microcontroller that listens for the sound of a smoke alarm to the exclusion of other sounds, and does this for a year on one set of batteries. Getting the device to reliably detect different smoke alarm was the hardest part of the project. And it doesn’t go off when you play the stereo!   

       You can't use other colors, or make it say "exit" and still produce an output with sufficient brilliance to be useful. Lasers that make anything other than red light cost many hundreds of dollars. Diffractive optics waste a lot of light – especially if they are making a non-symmetrical pattern.   

       We put a lot of thought into how the diffractive optics worked and how to get the biggest bang for the buck - optically speaking - while still being able to convey the idea of “direction”.   

       The electrical engineers didn’t want to use a motor to steer the beam because this thing could sit for years without being activated and collecting dust – the motor might not turn. However for what would have been “SafeEscape II” we had an elegant solution to this problem.   

       At the 2000 CES (Consumer Electronics Show) we had a small room set up, illuminated with a standard light bulb and with a SafeEscape. I was surprised how disorienting it was when we filled the room with smoke. The light bulb provided light but it was amazingly diffused and you still couldn’t see where to go. The Lasers actually did show the location of the door.
Limited Resource, Jun 29 2003

       You should delete this before someone decides to build it, patent it, and make a crapload of money.
davidcreede, Jul 21 2003

       Perfect idea. Has nobody picked up on it yet? With the price of laser diodes down to cents by now, you could leave out the mechanics for moving the beam and instead use, say, 10 diodes in a row and switch them in a running pattern. I wouldn't worry too much about getting the beam in the eye as long as the laser is no stronger than the standard laser pointer type. After all, even if somebody looks straight into the beam it is only on for a short period of time.
bother, Feb 23 2005

       A product using lasers was shown on discoveries this week on the science channel last night. It used a red and green laser that were positioned near exit signs. It also had a heat sensor that could tell if there was fire near the exit and if there was it would reverse the laser(essentialy keep the green on your right) These didnt shine on the floor but rather ran along the ceiling above your head. THe other benefit was that firefighters could follow with the red on the right ot trace the path of people trying to escape(to increase odds of rescusing people who were over come on their way to the exit.)
jhomrighaus, Aug 14 2006

       That is the one I linked.
Shz, Aug 14 2006

       Ooop Sorry [Shz]
jhomrighaus, Aug 14 2006

       The rebuilt Pentagon has the emergency lighting and EXIT signage down at floor level now - a lesson learned from the evacuation after the attack and evacuation.   

       I wonder how long it will take building codes to reflect the fact that when a building fills with smoke, everybody is on the floor and lights at ceiling level are useless.
normzone, Aug 14 2006


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