Temporal resolution technology of a soft X-ray picosecond framing camera based on Chevron micro-channel plates gated in cascade

We describe a soft X-ray picosecond framing camera (XFC) based on Chevron micro-channel plates (MCPs) gated in cascade for ultra-fast process diagnostics. The micro-strip lines are deposited on both the input and the output surfaces of the Chevron MCPs and can be gated by a negative (positive) electric pulse on the first (second) MCP. The gating is controlled by the time delay Td between two gating pulses. By increasing Td, the temporal resolution and the gain of the camera are greatly improved compared with a single-gated MCP-XFC. The optimal Td, which results in the best temporal resolution, is within the electron transit time and transit time spread of the MCP. Using 250 ps, ±2.5 kV gating pulses, the temporal resolution of the double-gated Chevron MCPs camera is improved from 60 ps for the single-gated MCP-XFC to 37 ps for Td=350 ps. The principle is presented in detail and accompanied with a theoretic simulation and experimental results.