Many Japanese emblems called "Mon" or "Kamon"are drawn on the traditional geometric design.  "Mon" was originated in order to distinguish individuals or signify membership in a specific clan or organisation. 
In old days, "Samurai-warriors" used their own "mon"on their clothes, flags, and so on to distinguish  enemy or not on the battlefield. It most commonly consists of a roundel encircling a figure of plant, animal, man-made, natural objects.