What was found
ACFT WAS IN DESCENT, WHEN AT APPROX FL 20 THE CREW HEARD A LOUD BANG WITH THE PILOTS WINDSHIELD SHATTERED. THE CREW STARTED THE QRH. ATC REQUESTED THE ACFT LEVEL OFF AT FL 17 & THE CAPTAIN SAID WAS UNABLE DUE TO THE UNKNOWN INTEGRITY OF THE WINDSHIELD. DECLARED AN EMERGENCY & VECTORED THE ACFT FOR LANDING AT THE PLANNED DESTINATION. LANDING WAS UNEVENTFUL. ACFT MX WAS NOTIFIED & THE WINDSHIELD WAS REPLACED. THE CONCLUSION WAS THE WINDOW WAS STRUCK BY FOD AT SOME POINT IN TIME. THE LOCALIZED DAMAGE PROGRESSED DURING FLIGHT UNTIL WINDOW FAILED.