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研究了不同铁电体阴极样品的发射行为表明在同样激励条件下，不同材料的铁电样品发射电流密度有显著差别，在集电极接地情况下，ＰＬＺＴ２／９５／５陶瓷测得的最大发射电流密度为３５Ａ／ｃｍ＿２，透明的ＬｉＮｂＯ＿３单晶为３８Ａ／ｃｍ＿２。样品的击穿阈值是极化难以达到完全翻转的主要障碍。分析了阴极表面金属栅的存在对铁电体发射的不利影响，“Ｅ⊥Ｐ”激励模式是克服这些困难的一个新途径。对两种最近试制的材料作了发射试验，观测到的最大发射电流密度超过了１００Ａ／ｃｍ￣２，估算该发射束的归一化均方根发射度为１０￣（－６）ｍ·ｒａｄ和归一化峰值亮度为１０￣（１２）Ａ／ｍ￣２·ｒａｄ￣２量级。
The emission behavior of different samples of ferroelectric cathode samples was investigated. It is found that the emission current density of ferroelectric samples with different materials is significantly different under the same excitation conditions. The maximum emission current measured by PLZT2 / 95/5 ceramic under collector grounding condition The density is 35A / cm_2, the transparent LiNbO_3 single crystal is 38A / cm_2. The breakdown threshold of the sample is a major obstacle for the polarization to reach full flipping. The unfavorable influence on the ferroelectric emission by the presence of the metal grid on the cathode surface is analyzed. The “E⊥P” excitation mode is a new way to overcome these difficulties. Launched on two recently tested materials, the observed maximum emission current density exceeded 100 A / cm2 and the normalized root mean square emissivity of the emitted beam was estimated to be 10 ~ (-6) m · rad And normalized peak brightness of 10 ~ (12) A / m ~ 2 · rad ~ 2 order of magnitude.