A VC who will marginalize an intelligent and productive co-founder just because that person has the wrong set of chromosomes - such a VC, I'm sorry, there's no polite way to say this - is a fucking moron. (I may be naive, but I find it hard to believe that such a VC exists). You do not want to do business with this kind of investor. You're creating a new, cutting-edge technology. A sexist, luddite dinosaur is not the type of person you want funding and influencing business decisions.
Don't hide the fact that you have a female founder. Her presence will filter out any sexist assholes and will ensure you find a true financial partner, whose interests align with your own.