Zoro is a free tool for Windows which makes it easy to work with certain applications for force, which can be difficult to focus on at any other screen.
It's easy to use: Just size the window in the field that you want to focus on. Once you've got it, hit ESC key, and the rest of the screen will go black, hit your Esc back again in the usual direction.
For example, there are a few other common options for activating and deactivating certain screen elements for graphic transition effects.
Zoro is an application tested for both its simplicity as well as for its helpful purposes.