Explained in detail: The surface tension measures the test pencil, other name reaches because of the pen, the electronics corona pen, the electronics corona processing pen, and the plastic film surface tension examination pen. The surface tension measured that the test pencil are the thin film surface corona (reaches because of) the testing tool, uses in determining the thin film electronics corona processing effect after specially. The surface tension measured that the test pencil have 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, 60 or above more than ten kind of different tensity test pencil, can test the plastic film surface tension accurately whether to achieve test pencil's value. Makes the user to understand clearly whether this thin film does suit in printing, compound or vacuum aluminum-plating and so on, thus controls the qualities effectively, reduces loss which, because the material quality unqualified creates.