Development of an LED reference light source for calibration of radiographic imaging detectors

TL;DR

This paper presents a stable LED-based reference light source designed to calibrate radiographic imaging detectors, ensuring consistent image quality over extended periods.

Contribution

It introduces a method for stabilizing LED light output and criteria for selecting suitable LEDs for long-term calibration in radiographic systems.

Findings

LED stability over several hundred hours achieved

Procedures for LED selection and preparation developed

Enhanced calibration consistency demonstrated

Abstract

A stable reference light source based on an LED (Light Emission Diode) is presented for stabilizing the conversion gain of the opto-electronic system of a gamma- and fast-neutron radiographic and tomographic imaging device. A constant fraction of the LED light is transported to the image plane of the camera and provides a stable reference exposure. This is used to normalize the images during off-line image processing. We have investigated parameters influencing the stability of LEDs and developed procedures and criteria to prepare and select LEDs suitable for delivering stable light outputs for several 100 h of operation.