Intense ray of light (5,4)
I believe the answer is:
laser beam
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">intense ray of light</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for laser beam that I've seen before include "Column of intensified light" , "Intense ray of light" , "Shaft of light or electromagnetic radiation" , "penetrating light" , "Shaft of light or electro-mechanic radiation" .)