At the moment, sights on Compound Bows deal with the issue of arrow drop over distance by having multiple different pins, each sighted in for a specific distance. However, this leaves the issue of the bow not being sighted in exactly at distances in between the pins. My project aims to deal with this issue by using a reflex sight (red dot sight) with a built range finder, which adjusts the reticle to the exact position it needs for the distance to the target. I wanted to first attempt to build a simple reflex sight as a proof of concept for myself, just so I could prove to myself that I was able to do so. Here are some pictures of what I was able to build:
Essentially, light from an LED or laser is bounced off of a mirror and onto a piece of plastic (or some other clear surface, like glass, or plexi-glass). Here is a diagram of how everything works:
My intent with this project is to eventually have a reflex sight that will adjust itself (like I mentioned above). I currently have two ideas for how to go about doing this, the first, is to use a display instead of an LED and simply change where on the display the dot appears, and thus, adjust where it shows up on the glass. My other idea is to attach a servo to the mirror, and adjust the angle at which the light is reflected.