Very silly question about the display screen

I have recently been lucky enough to purchase an NDX2, a great piece of kit. 

I am keen to know how to turn off the display screen. I am sure I have seen something posted earlier concerning the ND555, but I’m bug?!red if I can find it. Any tips?

Plus my second very dim question about an NDX2 manual. I’m not talking about the quick user guide. Is there a more in depth manual somewhere?

Many thanks