Windows10 "Dynamic Lock"
Windows10 is the latest update from windows, released on February 8, 2017, with a new fresh looking OS. It added a new OS feature "Dynamic Lock" for Bluetooth-equipped devices.
If Ur phone paired with your PC is not found within the Bluetooth range of your PC, Windows 10 automatically turns off the windows screen and locks Ur PC after 30 seconds interval.
Guide to Setting up "Dynamic Lock"
Step1: Pair Up your smartphone with your "Windows 10 PC"
Step2: On your windows10, switch to Settings-Devices-Bluetooth &other devices.
Step3: Add a device, tap Bluetooth, then choose your device from the list that appears.
Step4: Once pairing is complete, you can turn on Dynamic Lock.
Step5: Go to Settings-Accounts-Sign-in options. Simply click the checkbox under the Dynamic Lock “Allow Windows to detect when you’re away and automatically lock the device,”