The kinds of objects

The definition of the direct object is "The noun or pronoun that is affected by the action of the verb." and the "defintion of the indirect object is: "The noun, pronoun that receives the direct object." but there is another kind of object with this definition: "The noun or pronoun that is joined by a prepositon." e.g.: "He sat on the chair. He put his papers on the table". What should we call it, just "object"? i'm asking because i've seen a couple of examples that has recognized it as "indirect object"! plus Is there a more perfect definition for it?