A competing device is the Camera Lucida . "Camera Obscura" means "dark room", and the use of a pinhole in a window blind to form an inverted image of an outside scene on an opposite wall of a dark room.
I think that the answer is EMPHASIS ON HEAVENLY BEINGS.
Strasbourg style has the following characteristics:
1) emphasis on emotions
2) draping effect of stone clothing
3) emphasis on dramatic gestures.
I based my answer on what I read about the Strasbourg cathedral. Its art and sculptures revolve around Mama Mary, the Prophets, the 12 Apostles, and people depicted in the Bible. There is no presence of angels or any other heavenly beings.
It helps relax and brings nostalgic feelings depending on the song
