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As far as a high precision timer goes, what kind of IC would one need to procure to do such a task? This needs to be small, so a laptop is out. I guess I never considered using a microcontroller to control a timer IC. And by way of modulating laser light, I have no idea how to go about doing that. I had read about it and thought about doing something similar to FM radar, but I'm not sure if the laser component I was going to use is capable of it.
... and detecting it was something I was going to worry about later. Wink I figure I'd use some optics to amp up the signal a little and then a standard photoresistor.
About counters - there are very fast counter ICs. They can count cycles of RF signals directly. There are some simple products that make use of these. I think the front end of these is just a pre-amp connected to a counter. http://www.supercircuits.com/Wireless-Devices/RF-6http://www.thespyshop.ws/ns-15.html
Okay okay. Lets do the easy thing and consider this:What if we just measure parallax? Say you wanted to make a spotting scope style range finder. You could make the optical tube with a beamsplitter and a laser inside around 830 nm so you can't see it. Use a beamsplitter to reflect the optically magnified image through a bandpass filter (http://www.edmundoptics.com/onlinecatalog/displayproduct.cfm?productid=1903&showall) leading to one of thesehttp://www.sparkfun.com/commerce/product_info.php?products_id=8668So the camera will always see the field of view you're looking at through the optical tube, regardless of zoom. The image will be divided into a grid of 1300x1040 pixels. The only light it's going to see is the bandwidth of 830 nm projected by the laser (which you wont see). Using that grid, you could simply calculate the distance using some trig, knowing the distance of the laser to the beamsplitter because the grid will show the dot of the laser at varying distances from center depending on distance. Easy, right?