| 摘要 |
PROBLEM TO BE SOLVED: To measure a proper electrostatic capacitance.SOLUTION: A snow density sensor 1A includes: an electrode pair 11; a reference section 20a having a capacitor; a detection section 24 for detecting an output of the electrode pair 11 and an output of the capacitor of the reference section 20a; and a switch section 23 for connecting the detection section 24 to the electrode pair 11 and the capacitor of the reference section 20a. The snow density sensor 1A further includes an electrostatic capacitance calculation section 26 for calculating electrostatic capacitance between the electrode pair 11 with the use of the output of the electrode pair 11 connected to the detection section 24 by the switch section 23 and the output of the capacitor of the reference section 20a connected to the detection section 24 by the switch section 23. The reference section 20a is provided and the output of the capacitor of the reference section is used so that electrostatic capacitance between the electrode pair 11, which changes according to a measurement environment, is properly measured and a dielectric constant and measuring precision of the snow density sensor are improved. |
