Epson EMP 71 Instruction Manual page 29

[Settings for laptop and integrated LCD computers (when connected)]
When a laptop or integrated LCD computer is connected to the projector,
some computers require key commands or settings to change the output
destination of a video signal.
Keep "Fn" depressed while pressing "F0" to change the setting.
For details, consult the instruction manual of the computer you are using.
Manufacturer
NEC
Panasonic
Toshiba
IBM
SONY
Fujitsu
Macintosh
Tip:
Some computers may not be able to have images displayed on the computer screen at
the same time as they are being projected. In such cases, use only external output.
Output Switching Example
After restarting, the monitoring and sound on the
control panel are set to mirror the computer.
" " " "
Fn + F3
" " " "
Fn + F3
" " " "
Fn + F5
" " " "
Fn + F7
" " " "
Fn + F7
" " " "
Fn + F10
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