A Yeonjeok is a tool you need to put in an appropriate amount of water, grind ink, and paint. Until now, it has been regarded as a a beautiful work of art by paying attention to the various forms of Yeonjeok, but it was not well aware of the internal structure of water flowing and escaping.
Through this CT scan, it is possible to confirm the internal structure of the complexly manufactured Yeonjeok. Through the 3D image derived by CT scan, it was possible to accurately identify the inlet and outlet through which water enters. The inlet is a frog's mouth and the inner bowl is circular. It can be seen that a part of the side of the inner bowl was cut out and made as a water outlet.