Layer thickness gauge measurement range is mainly in the following aspects
(1) small size, easy to carry in the circuit, in addition to the selection of low-power microcontroller, the device as far as possible to use CMOS integrated circuits. As many components in the instrument have special requirements, especially high-frequency, high-voltage, low noise and other special devices, try to use MAXIM chip chip.
(2) Simple operation
The whole operation key is only five, do not need any operation training.
(3) Automatic calibration
As shown in the formula (1), in order to obtain the measurement results must also be corrected due to the probe contact with the test piece caused by the contact hysteresis and the hysteresis caused by other assemblies, we use the following formula to make corrections:
D = V (t - Tn) / 2 (4) where Tn is the initial value of the compensation factor. We use automatic setting of the compensation coefficient in the instrument to achieve the purpose of automatic calibration.
(4) Measurement status display
It can be prompted by the instrument whether to measure the thickness of the material or the speed of sound. If measuring the speed of sound, then input the thickness value; if measuring the thickness, then first carry out the auto-calibration and then measure. Also
Through the symbols on the display, you can know which measurement state the thickness gauge is currently in, prompting the operator.
(5) Coupling status display
If during the measurement operation, the measuring probe and the working surface are not coupled well, there will be a symbol to prompt the operator immediately.
(6) Backlight display
There is a backlight bar under the LCD display, which makes it easy to switch on the backlight when operating in poorly lit work sites.
(7) Metric/Imperial Conversion
The unit of measurement display is mainly considered to be in line with the international instrument unit.
(8) Upper and lower limit alarm
The operator can set the upper and lower limit alarm values according to his own needs, if the value is exceeded, the instrument will alarm automatically.
(9) Data saving
Each time the instrument is switched on, it will keep the previous measurement result automatically.
(10) Insufficient power supply voltage display
The power supply of the instrument adopts dry battery, and the circuit adopts low power consumption devices, the power supply is designed to work in intermittent small current mode, when the probe does not touch the sample, the instrument only works in the state of maintaining the start-up, and the circuit only starts to work when the probe touches the sample. When the probe touches the sample, the circuit starts to work. After a period of use, if the power supply voltage is insufficient, the instrument automatically reminds the user in order to prevent misuse.
(11) Changing different probes to achieve different measurement ranges.
