An image field in a database record only allows the insertion of an image in that field. For the case presented, if I understand the problem, a data structure must be modeled in the system, with a relation of 1 record to N image records.

The current default only allows you to insert one image at a time.  Therefore, to do this you need to do a manual routine for inserting multiple images. 

Alternatively, is to insert all the images you want from a given local folder, through some query in SQL.