I like robotics, photography and electronics, so I was planning on making a device that would involve all of my passions.
I'd like to build a color analyzer device, very simple to use: put it on the surface you want to measure the color and it tells you what R,G and B components are reflected by that surface.
In my understanding, I need to have a light source (or 3, one for each color component) and their wavelenght needs to be pure (well, wrong language I guess, I guess I mean it needs to contain only one wavelenght), and a light sensor, that would measure the amount of light reflected by it, then I use a microcontroller to make the calculations and drive an LCD and/or feed a host PC with those values.
I guess my question is: how can this be built to be very accurate? For example, if a given color in HSB space, I want the error in Hue, Saturation and Brightness to be inferior to +-0.1 deg.
I know of some commercial products that do exactly this, but they are so expensive. Is it feasible to build one for hobby?