showing the desktop with expose / AppleScript


I am looking for a way to start expose by applescript, to show the desktop without changing the focus.

I don’t want to call a key, like because all my Fx keys are already mapped.

My current script give the focus to the finder, which is problematic because sometimes I just want to grab a file sitting on the desktop to put it into the application I use.

In commandline I can run:
/Applications/ 1

This returns the focus to - so in theory it should work

Thanks for any suggestion