photoelectric counter

21 LETTERS · STARTS WITH P

photoelectric counter is a valid 21-letter word worth 31 points in Scrabble and 37 points in Words with Friends.

SCRABBLE WORDS WITH FRIENDS

P3H4O1T1O1E1L1E1C3T1R1I1C3C3O1U1N1T1E1R1

3 + 4 + 1 + 1 + 1 + 1 + 1 + 1 + 3 + 1 + 1 + 1 + 3 + 0 + 3 + 1 + 1 + 1 + 1 + 1 + 1 =31 PTS

DOUBLE WORD → 62TRIPLE WORD → 93

MEANING

What does photoelectric counter mean?