I am in a situation that can be more easily explained by using the following example.
Consider a person how works at a company that produces sunglasses. Based on the knowledge that he has acquired over the time, he comes up with an idea to produce UV protection sunglasses more efficiently. Then he leaves the company and start his own based on his idea. Can the original company sue him, assuming that he hasn't used any resources from the original company and he has worked on his idea on his own free time?