| Streak imaging tube(SIT) is an imortant diagnostic technique for the diagnosis of laser driven hydrodynamic radiative phenomenon. It is a kind of vacuum electronic devices with high spatial and temporal resolution, wide spectral response, large dynamic range and high detection sensitivity etc.As an instrument for the recording of fast transient phenomenon, the SIT has been successfully developed with high temporal resolution in the picosecond and subpicosecond regime. But the dynaminc range of the femtosecond SIT is very small and limits its apllication. Driven by the fast ignition technology in ICF studies, the improvement for the dynamic range of femtosecond SIT is imminent.The dynamic range and temporal resolution is a pair of contradictory unity, achieving a high time-resolved and the dynamic range will be decreased, and vice versa. The main content of this study is to design a new type SIT to develop a femtosecond SIT with a relatively large dynamic range. This can facilitate the applications of femtosecond SIT in ICF studies.This SIT was designed by using MATLAB software. The various factors influence temporal resolution and dynamic range of the SIT were analyzed in this article.The electric field distribution was calculated in finite element method, the random fluctuation in the electron emission process was simulated in monte carlo method, the electron trajectory equation was solved in runge-kutta method, the influence of the space charge effect and image charge effect were taken into account, the adaptive variable step length was adoptd in the calculation in order to save compution time.The whole length of 280 mm, Focus area length of 82 mm, magnification of 4.5. Drift region length of 144 mm, deflection sensitivity of 119.8 mm/kV, the temporal resolution of 400 fs and the spatial resolution of about 26.3 lp/mm were acchieved when the field intensity of 10 kV/mm was applied between the cathode and mesh. The dynamic range of 25~50 were obtained while the optical pulse width of 600~900 fs illuminate the cathode.In order to satisfy the needs of high speed scanning signal transmission, a kind of traveling wave deflector with bending line structure was designed by using HFSS software. it is a kind of deflector with larger passband width and high deflection sensitivity. The flying velocity of electrons inside the deflection plate and the transmission velocity of scanning signal on the deflection plate match each other. This is the main characteristics of traveling wave deflector. The traveling wave deflector length of 10 mm, longitudinal length of 44 mm, deflection plate spacing of 4 mm, passband width of 4 GHz, characteristic impedance of 70 ?, signal transmission distortion of 0.8% was achieved.The prototype tube was developed according to the design results, and experimental platform was built on basis of ultraviolet femtosecond laser, the static and dynamic test were carried on respectively. Static testing results show that the transverse magnification of 4 times, this confirm that intercepting the electrons with large emission angle can optimize the spacial structure of the electron beam and improve the quality of the image. Dynamic testing results show that tube spacial resolution will decrease under scanning status. The temporal resolution of the prototype tube was measured under different scanning speed. While voltage of 10 kV was applied on the anode, with the full screen scanning time of 148 ps, the tempotal resolution of 870 fs and the dynamic range of 18.8 were acchived.
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