a combined laser position detector , infrared emissivity target and television target includes a light - transparent substrate having a tv target on one side and an infrared target on a second side , with the two targets in registration with one another . alternatively , the tv and ir target can be on the same side . the substrate is affixed to a housing that includes light - emitting sources behind the targets positioned to direct emitted light through the targets and also includes a recess for receiving a laser position detector with an opening behind the targets to permit light to pass through the targets and to impinge upon the surface of the detector .