The hinge is a parallelogram mechanism of three rockers (green, blue and pink). Axis distances of the three rockers are the same. The yellow part to which the door is fixed, plays role of the connecting rod of the parallelogram mechanism.
The door handle and lock are not shown.
See a real pantograph door:
   • Monohinge Pantograph Door  

STEP files of this video:
https://www.mediafire.com/file/0cjota...
Inventor files of this video:
https://www.mediafire.com/file/nokle5...