When replacing the conventional “slow” luminescent screens (P20, P43) in picosecond image tubes by the “fast” ones (P46, P47), we found an increase in the decay time of “fast” cathodoluminophors (by a factor of 2–5) with increasing the number (from one to a hundred) of measured pulses. The consideration of the detected effect makes it possible to correct the problem statement in developing picosecond dissectors for recording repeated signals in the accumulation mode (e.g., synchrotron radiation).

The well-established PIF-01/S1/P43 picosecond streak tube, designed 30 years ago and still manufactured at the A.M. Prokhorov General Physics Institute, was modified by replacing its traditional P43 phosphor screen with a P47 one having approximately three orders of magnitude shorter decay time. The experimental measurements of this decay time were provided by PIF-01/S1/P47 image tube photocathode irradiation either with a single or a train of 8 ps laser pulses separated by 8 ns from each other at a 1.08 mu m wavelength. The results of our preliminary measurements of P47-BH phosphor (manufactured by Phosphor Technology Ltd) indicate the possibility of employing the PIF-01/S1/P47 streak tube for synchrotron diagnostics at a units megahertz repetition rate without the negative influence of 'ghost images' from the previous streak records.

It is shown that the LFS-3 crystal installed as a luminescent screen in a picosecond image tube provides the shortest afterglow time in comparisonwith all other fast-damping luminescent screens such as Y3Al5O12:Ce, Y2SiO5:Ce, and others we previously tested under similar conditions. The LFS-3 crystal exposed to single 8-ps pulses of 12–15-keV electrons shows the luminescence decay time no more than 250 ns by the level of 10-2 of the maximum.

In the present communication we describe the design of the sub-100 fs streak-tube that may be used for commercial streak cameras manufacturing. Careful attention is paid to preparing of a very smooth input photocathode substrate on which a low surface resistance (1-5 Ohm/) photocathode of S-1 type is deposited. Our estimations have shown that the photocathode surface roughness of about tens of nanometers may restrict the ultimate time resolution at the level of 100 fs. This is the reason why the photocathode substrate surface has to be smooth within the units of nanometers. The curvature of the photocathode surface is also very important to compensate the difference in the time-of-flight of electrons emitted from the central and peripheral photocathode areas. Further modernization was conducted with a photocathode-accelerating mesh assembly. The assembly may operate with 2 - 3 ns (FWHM) electrical pulses of 12 - 15 kV amplitude. In order to improve the S/N ratio in the streaked images, a shuttering system was incorporated inside the tube. As the result, a completely new femtosecond streak tube of PV-FS-M type was designed, manufactured, and tested.

The paper reports on the development of a new streak image tube with accelerating mesh and large (18 mm) photocathode work area. The tube's temporal resolution is close to one picosecond. To govern photoelectronic images the tube possesses shutter and deflector plates. Its geometric design allows uniform spatial resolution (more than 25 lp/mm) along the entire photocathode work area at 1.3 electron-optical magnification and negligibly small distortion. Being a continuation of the well-known PV and PIF - type streak image tubes developed in due time in GPI, the tube represents a promising tool for taking pictures of ultrafast processes in wide radiation spectrum range.