Foreign substance checking system

A foreign substance checking system that checks whether a foreign substance is present inside a bag-like container in which a powder is sealed and which has a region where the powder is visible from an outside,

• the foreign substance checking system comprising:
• a vibration device configured to apply a vibration to the container;
• a photography device configured to optically photograph an inside of the container through the region from the outside;
• and
• a determination device configured to determine whether the foreign substance is present inside the container based on an image of the container photographed by the photography device, wherein
• the vibration device includes a rotating shaft and a hammer rotating in conjunction with the rotating shaft and colliding with the container, and
• a region of an outer surface of the hammer to collide with the container has a flat surface;
• and
• wherein a ratio of a collision area, which is an area of the region on the outer surface of the hammer, to a work area corresponding to a space in which the powder can be sealed, on an outer surface of the container on which the hammer abuts is within a range of 1 to 4%.