Use Apple TV as a conference room display
You can use Apple TV as a conference room display so that anyone can easily share their screen from a Mac, iPhone or iPad using AirPlay. When Conference Room Display is turned on, a message appears on the display with AirPlay connection instructions and wireless network details.
Turn on Conference Room Display
Go to Settings
on Apple TV.Go to AirPlay and HomeKit, then select Conference Room Display to turn it on.
Customise and preview Conference Room Display
Once Conference Room Display is turned on, you can customise the way it looks.
Go to Settings
on Apple TV.Go to AirPlay and HomeKit > Conference Room Display, then do any of the following:
Display a custom message: Select Custom Message, then enter the message you want to display. (Your message appears only when Apple TV is in Conference Room Display mode.)
Set a photo background: Choose Select Photo, then choose Albums to pick a photo from your iCloud photo library.
Require a PIN for AirPlay: Select Require PIN Every Time to turn it on.
Anyone who wants to stream to your Apple TV while it’s in conference display mode is prompted to enter a 4-digit PIN shown on Apple TV.
See a preview of Conference Room Display: Select Preview. To exit preview mode, press
or 
on your remote.
Lock Conference Room Display mode
You can set Apple TV so that Conference Room Display mode is locked until a four-digit passcode is entered.
Go to Settings
on Apple TV.Go to General > Restrictions, then enter the passcode if required.
Make sure Conference Room Display is set to Restrict in the list of restricted items. For more information, see Set up parental controls on Apple TV.
Note: You use the same 4-digit passcode you set in Restrictions to unlock Conference Room Display mode. If you forget the passcode, disconnect Apple TV from the power point, reconnect it, then press and hold or on your remote as Apple TV restarts. This temporarily unlocks Conference Room Display mode. For more information, see the Apple Support article If you're asked to enter an AirPlay password on Apple TV.