There is a needle in the upper right corner of the health code, which represents the second injection of COVID-19 vaccine. The crown on the health code means that the owner of the health code has been vaccinated with novel coronavirus vaccine.
After the first injection, the health code will have a yellow box with a crown at the top, and a yellow injection needle will appear at the right angle on the left above the yellow box.
After the second injection, a yellow injection needle will also appear on the upper right of the yellow square frame. The crown and needle are designed so that when people show their health codes in public places, it is convenient for health code inspectors to quickly know your health and vaccination.