CAPT'S FORWARD WINDOW ON B757-200 BEGAN ARCING AND DELAMINATED DURING CRUISE. OUTER PANE THEN SHATTERED AND FLT CREW DECLARED EMER; INITIATED EMER DESCENT; AND LANDED AT NEAREST SUITABLE ARPT.

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WHILE AT CRUISE FL360; CAPTAIN'S FORWARD WINDSHIELD BEGAN TO DELAMINATE AND DISCOLOR IN LOWER RIGHT QUADRANT; FOLLOWED BY SPARKING; ARCING AND SMOKING. WENT TO FM PROCEDURE FOR WINDOW DAMAGE WHICH LED US TO DEPOWER THE WINDOW HEAT. SHORTLY AFTERWARDS; THE DELAMINATION CONTINUED TO INCREASE IN SIZE; FOLLOWED SHORTLY THEREAFTER BY COMPLETE SHATTERING OF THE ENTIRE OUTER PANE FULL SPAN. IMMEDIATELY TOLD ATC WE NEEDED A LOWER ALTITUDE AND AFTER GIVEN STEP DESCENTS; WE DECLARED AN EMERGENCY WHILE DONNING OUR O2 MASKS AS A PRECAUTION WHILE PERFORMING THE QRC FOR 'CABIN ALTITUDE/RAPID DEPRESSURIZATION' AS A PRECAUTION FOLLOWED BY AN 'EMERGENCY DESCENT' QRC TAILORED FOR THE SITUATION -- WE WERE ALREADY IN A DESCENT AS PER ATC PER OUR REQUEST. ATC COMMUNICATION BECAME EXTREMELY POOR AT LOWER ALTITUDES COMPOUNDED ALSO BY MASK COMMUNICATION IN DESCENT. CAPTAIN OPERATED AIRCRAFT AND HANDLED ATC COMMUNICATIONS WHILE FO ESTABLISHED COMMUNICATIONS WITH COMPANY. EXTREMELY POOR COMMUNICATIONS WITH COMPANY THROUGH VARIOUS MEANS. IN THE MEANTIME; CAPTAIN ASSESSED NEAREST SUITABLE AIRPORT AND DETERMINED ZZZ WAS BEST AND MOST SUITABLE CHOICE. APPROACHING LOWER ALTITUDES; USE OF MASKS WAS DISCONTINUED AND CONTROL OF AIRCRAFT WAS TRANSITIONED TO FO DUE TO LACK OF PROPER VISIBILITY THROUGH CAPTAIN'S WINDSCREEN AND DUE TO PERCEIVED FLEXING AND/OR BOWING OF WINDSCREEN WHILE OPERATING AT REDUCED SPEEDS. CONCERN FOR WINDOW STRUCTURAL INTEGRITY BECAME A MAJOR CONCERN. CABIN ADVISORY COMPLETED; CONFERRED WITH DISPATCH DESPITE THEIR INPUT WITH CUSTOMER SVC ISSUES; DETERMINED ZZZ WAS BEST SUITABLE AIRPORT. TERRAIN; COCKPIT VISIBILITY AND LANDING PERFORMANCE/RUNWAY LENGTH WEIGHED AGAINST ZZZ1. AS NOW PNF; CAPTAIN PERFORMED ALL CHECKLISTS AND I PERFORMED THE VFR LANDING AT ZZZ. ALL LANDING DATA; NOTAMS AND DIVERSION CHECKLISTS REVIEWED AND LANDING OK'D BY DISPATCH. AS AN EMERGENCY AIRCRAFT; WE VERIFIED EMERGENCY EQUIPMENT AVAILABLE THROUGH UNICOM AND DISPATCH. CAPTAIN AND ENTIRE CREW ASSESSED ANY AND ALL SPECIAL NEEDS WITH PASSENGERS -- PASSENGERS WERE KEPT INFORMED THROUGHOUT THE ENTIRE EVENT AND WERE COMFORTABLE WITH THE OUTCOME AFTER LANDING. COMMUNICATION AND COORDINATION WITH COMPANY CONTINUED TO FACILITATE CARE FOR AND HANDLING OF PASSENGERS AND SPECIAL NEEDS WHILE PASSENGERS WERE WAITING ONBOARD WITHOUT NORMAL MEANS OF DEPLANING. ULTIMATELY; EQUIPMENT WAS OBTAINED FOR USE IN DEPLANING ALL PASSENGERS AND CREW. ARRANGEMENTS WERE MADE FOR ONBOARD CATERING FOR ALL PASSENGERS AND CREW -- CONSIDERING SPECIAL DIET NEEDS AS WELL. WE CONTINUED TO COMMUNICATE ALL UPDATES TO PASSENGERS DURING THE LENGTHY DELAY ONBOARD AND WERE PROACTIVE IN CONTINUALLY DETERMINING SPECIAL NEEDS AS THEY AROSE.