Light Transport; Low Wing; 2 Turboprop Eng
Air Traffic Control Fully Certified
Air Traffic Control Time Certified In Pos 1 (yrs) 6
Troubleshooting; Situational Awareness; Distraction; Human-Machine Interface; Confusion
ATC Issue All Types; Deviation / Discrepancy - Procedural Other / Unknown
ATC Equipment / Nav Facility / Buildings
Aircraft X was landing on 24R.  As he was rolling out; I noticed on the ASDE-X that his target & tag disappeared from the ASDE-X display; but the digital display of an Aircraft landing or departing on 24R was still lit. As Aircraft X exited at Zulu I told him to cross 24L and to contact ground.  His target & tag still weren't showing on the ASDE-X.  It never showed even while he was taxiing eastbound on Echo.  I reported the incident to the supervisor.This is the second time I observed an incident like this occur relating to a small sized aircraft. It happened a few days ago concerning a BE35 aircraft on the same exact path as Aircraft X.  I did not file a report on the first event.  But after seeing it happen again; I figured that there must be something wrong that needs to be addressed.I simply recommend that the Techs in charge of installing the particular ground radar sensors somehow raise the sensitivity level so that each target is captured and displayed as a moving target.  But I mainly recommend that all checks be accomplished to determine the cause of this occurring.  That way a solution can be attained.
An LAX Local Controller; while watching an aircraft on the ASDE-X; sees the target and identification tag disappear. The digital display of a target was still showing. He had seen this before on another small aircraft but didn't do anything about it; so this time he reported it.