What was found
AIRCRAFT WAS GROUNDED: AN EMERGENCY WAS DECLARED ON FINAL APPROACH INTO CLT DUE TO DURING LANDING GEAR EXTENSION, WHEEL SD PAGE SHOWED 1/2 OF NOSE GEAR DOWN INDICATION RED. LANDING GEAR INDICATIONS ON GLARESHIELD PANEL SHOWED NOSE WHEEL GREEN LIGHT. LANDING GEAR DOORS NOT UP AND LOCKED WHEN LANDING GEAR IS EXTENDED AND DISPLAYED AS INOPERATIVE SYSTEM ON STATUS PAGE OF LOWER ECAM. THE AIRCRAFT LANDED SAFELY AT CLT WITHOUT FURTHER INCIDENT. MAINTENANCE FOUND NOSE LANDING GEAR PROXIMITY SENSOR TARGET 19GA MISSING AND INSTALLED IT PER AMM 32-31-73. A SATISFACTORY OPERATIONAL CHECK WAS ACCOMPLISHED.