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Laser Lamp

Shine a laser at cordless lamp
  (+4)
(+4)
  [vote for,
against]

Yeah, yeah, energy losses, but I want a lamp I can move anywhere in the room. It's got a photovoltaic cell on top and a sleek laser light fixture hard-wired into the ceiling. The laser light fixture has lamp-finding technology created by VSP that causes the laser to shine right at the photovoltaic cell.

The lamp also has a usb connection for my phone, and if possible, a whatever connection for my computer. Enough LED light to read by.

In the bottom of the lamp is a big-ass bunch of lthium batteries that trickle charge, and a robust couple of speakers for listening to podcasts when I'm washing the dishes.

nomocrow, May 30 2014

[link]






       This all makes sense apart from the bit after you start.   

       You want a photovoltaic-powered laser? Or a laser- powered photovoltaic lamp? Or what?
MaxwellBuchanan, May 30 2014
  

       Laser-powered photovoltaic lamp. Mainly to avoid the necessity of extension cords.
nomocrow, May 30 2014
  

       There is a significant blinding danger here. "Safe" lasers have an energy output of milliwatts (thousandths of a watt--I'll arbitrarily pick 5 milliwatts). It would take a rather longish time to charge that lamp. Assume 25% efficiency of the photovoltaic cell, and a 5-watt LED lamp, and 100% efficiency of the rechargeable battery (dream on!), and if you want the lamp to shine for 5 minutes, then you need to charge it for something like 20,000 minutes.   

       A more powerful laser will cause a faster charge time, of course -- but if you accidentally get that beam in your eye....
Vernon, May 30 2014
  

       Magnetron ?
8th of 7, May 30 2014
  

       Why not just diffuse the laser light when it hits it?   

       Nah, a much better idea is to cover two opposing walls of your room with tinfoil, and connect a high voltage AC source to them. This turns your whole room into a capacitor, and has the advantage that the field strength inside is independent of position. The result is that ordinary CFL bulbs will light up without being plugged in.
mitxela, May 30 2014
  

       A search for VSP turned up this...   

       " Very Serious People, a phrase coined by Paul Krugman for pundits that somehow remain being considered respectable in spite of being consistently wrong about everything "
normzone, May 30 2014
  

       //CFL bulbs will light up without being plugged in. //   

       A magnetron will do that, too. Pick a frequency that doesn't resonate with any molecules in mammalian tissue, though ...
8th of 7, May 30 2014
  

       Giant capacitor wins on the following merits: transmission efficiency, uniform power wrt position, historical (a feature of Tesla's laboratory), and the fact that you get to live in a giant capacitor.
mitxela, May 30 2014
  

       Or, instead of laser, you could install a bulb that lights up the whole room. Then your lamp has wide spectrum solar panels, and converts the unfocused (and thus not dangerous) light into power for it's own bulb, which gives you light to read by.   

       Hm. It seems like there might be a couple of unnecessary steps there.
MechE, May 30 2014
  

       //"Safe" lasers have an energy output of //   

       but seriously, nice idea [+]
Voice, May 30 2014
  

       So you could have 1000 “safe” 5mW lasers mounted at all points of the room, which all converge on the lamp unit. That way you can't be blinded by them as you can only put your eye in the path of one at a time.
pocmloc, May 30 2014
  

       //which all converge on the lamp unit. That way you can't be blinded by them as you can only put your eye in the path of one at a time. //   

       Let's take this as an exercise for the class. Now, has anyone spotted the flaw in this ? Like the inherent contradiction between "all converge on the lamp unit" and "only put your eye in the path of one at a time."   

       If there is a "point of convergence" then as that point is approached, the power density increases, towards 1 watt at the focus. From a "not going blind instantly" point of view (heh heh), 1 watt of laser power could best be characterised as 'unhelpful' ...
8th of 7, May 30 2014
  

       Alternatively, you could fit an always-on extra powerful UV lamp in the centre of the room, with phosphors to kick it into the visible where needed. Unfortunately your CFL bulbs are made of a glass specifically chosen to block out UV, so to use them you'll have to smash them open and expose the bare phosphor coating. (Make sure to breathe in as much mercury vapour as possible. It's rumoured to be an aphrodisiac.)   

       On the other hand, you could invest in a particle accelerator and direct the charged beam at your "lamp" causing Bremsstrahlung radiation which if the energies were correctly adjusted could lie in the visible range. On the original hand, this suffers from all the disadvantages of a laser-based lamp system with the added risks of cancer and massive discharge arcs if the lamp is ungrounded.
mitxela, May 30 2014
  

       // If there is a "point of convergence" then as that point is approached, the power density increases, towards 1 watt at the focus. From a "not going blind instantly" point of view (heh heh), 1 watt of laser power could best be characterised as 'unhelpful'//   

       The lasers need only converge to the extent that they all hit the photovoltaic. As long as it's large enough, the beams need never be closer together than 5mm.   

       And before you point out that they'll converge on the far side of where the photovoltaic was meant to be - not necessarily.
MaxwellBuchanan, May 30 2014
  

       Yes I suppose if you usually put your eyes right up against the lamp...?
pocmloc, May 30 2014
  

       We never did laser-illuminated vampires, did we?
lurch, May 31 2014
  

       Apparently not, but it's highly likely we're now going to ...
8th of 7, May 31 2014
  

       Or zombies. They are cooler, if you know what I mean.
blissmiss, May 31 2014
  

       Very Smart People.   

       And couldn't you kind of cone out the laser so it wouldn't burn up your eyes and put the cell up high enough so your eye wouldn't find it's way up there?
nomocrow, Jun 01 2014
  

       // Why not just diffuse the laser light when it hits it? //   

       Correct. Scrap the PV cell and batteries; they represent a huge loss of efficiency on the order of 90%.   

       Let the laser hit a reflective element in the centre of the bulb which scatters it out to the glass layer, which is sandblasted to an opaque white for dispersion.   

       And/or use a UV laser and have the bulb coated with the phosphors from a fluorescent bulb.   

       The emitting laser can be mounted above head height, (ie, above line of sight) to the wall or ceiling, for safety, and prevented from aiming below horizontal. A motion detector can be connected to an interlock which switches the laser off if a moving object is detected within its firing range.   

       Line your ceiling with steel, add a magnet and some shuttlecock fins to your lamp, and you can throw it anywhere on the ceiling. The motion detector tracks the lamp, determines its position, and fires a short, low-power UV laser pulse at it. If a visible spectrum flash is returned, that is the lamp, and not your head, so it switches to full power.
BunsenHoneydew, Jun 07 2014
  
      
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