How to render in Display2(another monitor)?

Hi everyone,

I'm try to configure Vuforia ARCamera to display to another display(i.e Display2, another monitor).
However, the Display2 only shows blackscreen while it works well with Display1 setting.
The followings are my test environment and test flow.

[Environment]:
Software:
Unity 2017.3.1f1 Personal (64-bit)
Vuforia SDK 7.0.47
Microsoft Visual Studio Commnunity 2017 Version 15.5.5 with UWP SDK installed
Windows 10.0.16299

Hardware:
PC/Laptop + Ordinary UVC (USB Video Class) Webcam
Another LCD monitor

[Flow]:
1. Create a new Unity 3D project.

2. Search Unity Asset Store, and then download and import "Vuforia Core Samples".
(Sample code "Core Feature" in https://developer.vuforia.com/downloads/samples)

3. Open scene "3-ImageTargets"



4. In "Vuforia Behavior"->"Open Vuforia configuration" of ARCamera GameObject, check "Databases"->"Load VuforiaMars_Images Database" and "Activate".



5. Click "Play" to confirm that Vuforia SDK works well in Unity editor mode.



6. In order to to confirm that Vuforia SDK works well in release build, I build it as an UWP App.
In "Build Settings", select "Platform" to "UWP" and edit "Scenes in build" and "Player settings"->"XR Setting"->"Virtual Reality Supported" as below.





7. "Build" it successfully. Then, build and deploy it with Visual Studio.
It works well.

8. Now, connect laptop to the other monitor and set the project mode as "Extend".

Image8: (Because one post only can attach five images. Image8, Image9, and Image10 are attached in the next post.)

9. Change "ARCamera"->"Camera"->"Target Display" from Display1 to Display2.

Image9:

10.Repeat step.6 and step.7.
The rendering content not only still shows in Display1 but also blinks(only white and grey) rapidly.

Image10:


Could anyone have an advises to this Display2 problem?
Thanks.

Sincerely,
Stef

 

Attach Image8, Image9, and Image10.

Image8:


Image9:


Image10: