Transverse energy distribution analysis in a field emission element with an insulator funnel

In a field emission display panel, an insulator funnel, which is called Hop funnel, has been used to separate the cathode and the anode. Secondary electrons generated on top of the insulating surface due to the primary electron bombardment are drawn to the exit hole of the funnel by the electric field. Therefore, the energy distribution of these secondary electrons influences the quality of the FED. In this paper, an experimental instrument has been built to study the energy distribution of the secondary electrons on the anode screen in a field emission display element. Simultaneously, the relevant simulation with different primary conditions has been made. The both numerical simulation and experimental results are compared, and it is found that: (1) The experimental results can be well described by the numerical simulations; (2) the distance between the emitting center and the funnel hole has a dramatic influence to the number of electrons that can leave the hop funnel; (3) the distance between the anode and the funnel does not have a strong influence on the energy distribution; (4) the transverse energy distribution of hop electrons is very low.