A80 Controller expressed concern regarding the Conflict Alert (CA) feature of the ARTS system noting the audio and visual indications are erratic leading to controller complacency.

Narrative

Atlanta ARTS has a 'glitch' or something where the Conflict Alert (CA) will activate for a very short time; fractions of a second; but once activated; the CA 'horn' goes off for the entire preset time. Sometime the CA is for such a split second you can barely see the 'CA' in the data block before it disappears; but the 'horn' still goes off. Sometimes the aircraft 'conflicts' with itself; sometimes it's with another aircraft; sometimes it will go on; off; then right back on; providing multiple alerts. The result is that the CA 'horn' is heard so often that sometimes it becomes second nature; and could lead to complacency. Today it happened on DR-S about 10 southwest ATL with Air Carrier X (ATL departure climbing to 100) and Air Carrier Y (ATL arrival descending to 110; worked by TAR-H). I can see where the machine could have thought it was in conflict; but why did the 'CA' disappear? If the aircraft were in conflict; show the controller; but the 'CA' in the data block disappeared after about a quarter second.