China International Youth Conference on Electrical Engineeing (CIYCEE 2025)

High-speed CCD imaging systems are critical diagnostic equipment for observing rapid phenomena such as magnetohydrodynamic instabilities, tearing modes, and edge localized modes in tokamak plasma research. In the J-TEXT tokamak device, achieving simultaneous observation of different plasma cross-sections or different physical quantities requires maximizing diagnostic information under the constraints of limited observation windows and camera resources. Traditional single-optical-path imaging systems face contradictions between spatial coverage and temporal resolution when observing complex plasma phenomena. To simultaneously acquire information from multiple spatial locations or multiple physical parameters, dual-optical-path simultaneous imaging must be achieved while maintaining high temporal resolution. Through the design of a dual-optical-path optical system, we have realized simultaneous imaging of two independent fields of view on a single CCD sensor. The system adopts a dual-optical-path single-sensor imaging architecture, capable of acquiring dual-channel images with 1920×1080 resolution at a temporal resolution of 1 ms. Key aspects of system optimization include precise design of the light-transmitting aperture and development of camera calibration algorithms. Aperture optimization requires finding the optimal balance between light throughput, image quality, and crosstalk suppression. For the dual-optical-path simultaneous imaging, we have developed specialized calibration methods to ensure geometric correspondence and consistency of optical parameters between the two optical paths.
 

Dual-optical-path Imaging, Tokamak Plasma Diagnosis, High-speed CCD, Imaging System Optimization, Camera Calibration