| 摘要 |
PURPOSE:To enable exact counting of the photoelectrons from a sample by counting the respective photoelectrons released from the sample and the wall of an air counter, counting further only the photoelectrons from the wall of the air counter and determining the difference in the count per unit time. CONSTITUTION:The light from a light source 6 is made monochromatic by a spectroscope 7 and irradiates a sample 9 in an air counter 10. The photoelectrons 1 from the sample 9 are supplied through grids G2, G1 and an anode A to a counting device 3. The photoelectrons 2 from the wall of the counter 10 are supplied through the anode A to the device 3. A count value N1 is obtd. from said device. The voltage of the grating G1 is increased to decrease the intensity of the electric field and to prevent electric discharge at every arrival of the photoelectron 1 at the anode A during the period T2 next to the period T1. A negative potential barrier is created continuously to the grid G2 to prevent the arrival of the photoelectron 1 so that only the photoelectrons 2 are selectively counted and a count value N2 is obtd. The count value of only the photoelectrons 1 is obtd. from the value N1-N2 if the period is made T1=T2. |
