Electrical devices are described. A system is established and is provided with: an inputoutput unit device capable of inputtingoutputting data by the direct writing on a display screen with a pen; and a controlarithmetic device connected to the inputoutput unit device and reflecting the data inputted on the display screen to the screen. A UV lamp converts oxygen contained in the closed ionization chamber to ozone, which removes contamination in the closed ionization chamber, Continuous gas flows can alternate between one ionization chamber to the other.