How to decide a camera (image sensor + lens) based on an application

[avlsi]

Hi ,

I am planning to build a camera system for a medical application.

I know what is the object size and the distance at which it has to placed from the camera setup. (Actually if I place the camera setup too far, there is too much loss in the light intensity hitting the camera setup. So it has to be as close as possible.)

But I donot know whether there is any systematic equation based calculations for choosing the lens and the image sensor(pixel pitch, full well, DR)

I would be happy to know any of the references or sources to understand more about the mathematical part of the camera design.