found this as well:

vb Code:
  1. MonitorSet False
  2.  
  3. to turn the monitor off or
  4.  
  5. MonitorSet True
  6.  
  7. to turn the monitor on
  8.  
  9.  
  10. Const MONITOR_ON = -1&
  11. Const MONITOR_OFF = 2&
  12. Const SC_MONITORPOWER = &HF170&
  13. Const WM_SYSCOMMAND = &H112
  14.  
  15. Declare Auto Function SendMessage Lib "user32" ( _
  16. ByVal hWnd As IntPtr, _
  17. ByVal Msg As Integer, _
  18. ByVal wParam As Integer, _
  19. ByVal lParam As Integer) As Integer
  20.  
  21. Function MonitorSet(Optional ByVal bOn As Boolean = True) As Integer
  22. MonitorSet = SendMessage(Handle, WM_SYSCOMMAND, SC_MONITORPOWER, IIf(bOn, MONITOR_ON, MONITOR_OFF))
  23. End Function