In my opinion, you need a pair of sunglasses not just for protecting your eyes from the sunlight, but also appearing professional.
Therefore, you need a pair of black thick framed rectangular sunglasses.
Black color makes you professional and reliable. Gaudy colors dampen and destroy your professional image and your reliability.
All right, i can see that you are very concerned about your work. That is impressive. So, as a matter of fact, I would recommend polarized sunglasses to you. Because polarized sunglasses are better than conventional sunglasses in terms of their UV protection and some harmful rays such as reflections from water or something. And with those sunglasses, your vision would be very clear and have better performance at work.
I suggest the type of ray ban sunglasses with polarized function for you. The ray ban sunglasses are perfect at the design. In addition, the quality of ray ban sunglasses is so perfect which you could wear for many years. You could go to the real store of eyeglasses to pick one with your favorite type. You could also go to the online stores to buy one which save you a lot of money.