Batch Process - Insert icons into each pdf-side

Hello community,

I want to implement an icon with the help of javascript on each side of the pdf. I have already implement two text field on each side. It works fine with:

for (var p=1; p<this.numPages - 1; p++)

{
var textfield1 = this.addField("Text1" + p, "text", p, [75,130,100,110]);
textfield1.value="Notizen:";
textfield1.readonly = true;
var textfield2 = this.addField("Text2" + p, "text", p, [75,110,520,30]);
textfield2.multiline=true;
textfield2.strokeColor=color.green;
var textfield3 = this.addField("Text3" + p, "text", p, [75,520,100,500]);
textfield3.value="Notizen:";
textfield3.readonly = true;
var textfield4 = this.addField("Text4" + p, "text", p, [75,500,520,420]);
textfield4.multiline=true;
textfield4.strokeColor=color.green;
}

But up to now I can not implement an icon into the alreading existing text fields.I do not know how I can implement an external icon into Adobe pdf. 

Further Questions:

Is this possible with an text field or only with buttons?

Is it better to use images than icons?