What is A 50 year old male patient complains of reduced mouth opening. Patient gives h/o RTA 1 week back. Submentovertex view x-ray was taken which revealed zygomatic arch fracture. Which of the following is true regarding the central beam in this x-ray- and explain in detail?
Submentovertex view-
The central beam is perpendicular to the image receptor, directed from below the mandible toward the vertex of the skull (hence the name submentovertex), and centered about 2 cm anterior to a line 
connecting the right and left condyles.
White and Pharoah, Oral radiology, ed 7th, pg-161