ASRS 2060840

Aircraft X departed Runway 28R for a right down departure. The aircraft drifted to the south into the departure path of Runway 28 left, which had Aircraft Y departing. Aircraft X was reported to be right on top of the Aircraft Y by 100ft, radar display replay confirms altitudes. Aircraft Y reported it to Local Control 1, which told Local Control 2; at this point Aircraft X was in the crosswind turn away from Aircraft Y. Even when told about the situation I could not see both aircraft due to the Window Shades blocking my view, they were pulled half way down. When the shades are like this we can’t see the top half clearly, but others like it, because it blocks the sun. I personally cannot stand the way we do our shades, but I’m in the minority and the majority rule. I was also busy looking at the arrivals during the event to ensure separation between arrivals. With the amount of volume that we have, I recommend implementing a local assist position to help get more eyes out the window to prevent these types of situations. Our local assist position has been waiting for approval for years.