How to adjust the scale of the P40 screen?

Pictuer Format:

1.Auto/Full/Unscaled：16 : 9

2. 4 : 3

Steps：

1. Use an HDMI cable to connect the projector to your PC

2. Press the signal source button on the remote control - switch the signal source to HD

3. Press the menu button "≡" on the remote control and click on "Display mode" on the screen to enter the Picture Format for selection