The optical element, includes a first voltage application electrode 13, {HEAD ~ a first opposing electrode} 17 arranged in {TAIL ~ opposition} to the first voltage application electrode 13, and a first phase changing layer 15 arranged between the first voltage application electrode 13 and the first opposing electrode 17 
The optical element , includes a first voltage application electrode 13 , { HEAD ~ a first opposing electrode } 17 arranged in { TAIL ~ opposition } to the first voltage application electrode 13 , and a first phase changing layer 15 arranged between the first voltage application electrode 13 and the first opposing electrode 17
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH