I'm in the process of designing an automated home for my Parents house and I'm wondering if it is at all possible to build/purchase a switch that can be thrown with a laser pointer. ie. Instead of carrying around a remote and installing a bunch of ir sensors in each room is there a switch/sensor that can be activated with a simple laser pointer - since they are so tiny and fit nicely in pockets or even a neclace? essentially allowing me to point the dot at whatever device I want to control (not at the device, but at a sensor near by of course) to turn it on/off. I'd like to do this with Lights, climate control, and in some rooms music and video. Thanks in advance mighty brains of bit-tech.
I came across a diy tutorial that's indirectly related to this. A guy was using a "laser mouse" and a laser pointer, and made it work so that pointing the laser in some direction made the pointer move on the computer. And he added some "mod" to it so that he also can "click" by pointing his laser to some photosensitive cell. See here: http://www.instructables.com/id/Control-your-Computer...-with-a-LASER!/ The step 4 of that tutorial tell which components are required for "clicking". I guess there will be some changes to be made, because you basically want to control AC current instead of a mouse pointer, and because you want the "switch" to be premanent where a click only require the circuitry to be closed for a second (while the laser passes)... But I think it will give you some directions.
Downside is you'd need to be very accurate to get the very narrow beam over the very small sensor from a few feet away. Not so "incredibly cool" when it takes a few seconds waving the pointer about to do anything.
Thanks ThaNerd but I have to agree with cpemma. I was hoping to fabricate something that would look like a motion sensor, something with a ~2" hit area. Does anyone have any suggestions on how to fabriacate a laser activated switch with a large target area? perhaps, something like this:
i think RF might be a better option, like say WiFi attached to a smallish pc with a breakout box of serial controlled Relays.. They it could be controlled from say a smart phone via web interface anywhere in the house.
I like the idea and I considered that, but I want a tiny remote... like a laser pointer. Also it will be used by three people, of which only 1 (me) has anything that could be considered a smart phone.
Ok I cant remember what there called but take a look at beam counters. (box that shoots a IR beam that can be set to turn a switch on or off when broken)
Thanks Tec but those wouldn't work, there is no laser beam sensor like that. IR. yes, but laser, no. I'll just have to experiment some more. Thanks guys.
What do advanced laser tag games use? There's a DIY laser tag site with this sensor schematic (but it's for IR) http://www.lasertagparts.com/mtsensors.htm
I think it would be possible to put a lens in front of a photo transistor to use it as a switch. Or a prism to focus the light onto it.
Any good at soldering? Would an LDR work? i did a AS level project where i had a laser "trip wire" of sorts... like in the films. Light Dependant Resistor-Veriable resistor to adjust the sensativity, i had mine tuned up so it took allot fo light to set the thing off... Can easily modify it to include a relay to act as a switch... If thats the type of thing you are looking for i'll dig out my designs and post them : )
Any photodiode/transistor for visible light would work fine, photodiodes dont care if the light is coherent or not, So you may want to use an differentiator to look for a rapid change in light, and a filter on the front to keep ambient light from bothering the diode.
I would think using something like IR led's would be much more convenient as you would a much larger cast area and you woulnd't have to aim at a 2" target from 15 feet away. Any specific reason you want to use a laser? unless you plan on turning on the lights from 80 feet away I don't see an advantage over high powered Ir Led's that can easily be picked up by off the shelf or modded hardware
@jhanlon303 - Hahaha, thanks for the credibility backing mate. @metarinka - ...it's more of a bling thing really + I'm planning on doing some crazy stuff with fiber optics, I don't think that IR can travel though fiber in the same way a laser can. @ConKbot of Doom - I'm thinking the same thing at this point, in fact it was in researching photodiodes that I stumbled across yet another project - an interactive LED board. Thanks for the suggestions guys... more research will be needed methinks.
