Agree with "asker" and Forrest Liang -
Cannot use "電動" in here.

Also, it is not as simple as "pulling the drapes" - because pulling the drapes may not offer the FINE adjustment needed for various room brightness.

I don't know what it is, but NOT pulling the drapes, because if you have a guest in your room, pulling the drapes may not be very appropriate.

I think I will describe it as - 戶內光線調節設施 or
光線調節設施窗

I think its function should be
1. You can FINE adjust the room brightness, but at the same time
2. You still can see what is out there through the windows!