Use DPMS (Display Power Management Signaling) to turn screen on or off.
Display DPMS settings.
$ xset q
Keyboard Control: auto repeat: on key click percent: 0 LED mask: 00000002 XKB indicators: 00: Caps Lock: off 01: Num Lock: on 02: Scroll Lock: off 03: Compose: off 04: Kana: off 05: Sleep: off 06: Suspend: off 07: Mute: off 08: Misc: off 09: Mail: off 10: Charging: off 11: Shift Lock: off 12: Group 2: off 13: Mouse Keys: off auto repeat delay: 660 repeat rate: 25 auto repeating keys: 00ffffffdffffbbf fadfffefffedffff 9fffffffffffffff fff7ffffffffffff bell percent: 50 bell pitch: 400 bell duration: 100 Pointer Control: acceleration: 2/1 threshold: 4 Screen Saver: prefer blanking: yes allow exposures: yes timeout: 0 cycle: 0 Colors: default colormap: 0x20 BlackPixel: 0x0 WhitePixel: 0xffffff Font Path: /usr/share/fonts/X11/misc,/usr/share/fonts/X11/Type1,built-ins DPMS (Energy Star): Standby: 0 Suspend: 0 Off: 0 DPMS is Enabled Monitor is On
Use DPMS to force screen off.
$ xset dpms force off
Use DPMS to force screen on.
$ xset dpms force on
Perform operation on specific display.
$ xset -display :1 dpms force off