Analysis and calculation of the veiling glare index in optical systems

Veiling glare index (VGI) is an important criterion to evaluate the image quality that can be obtained with an optical system. The VGI can be measured after the design of the optical system. If the measured VGI of an optical system does not meet the requirements, the stray-light suppression must be adjusted to improve its effectiveness. To facilitate this process, we propose a method to calculate the VGI of an optical system during the design stage. In the method, a programme called TracePro is used to model and analyse the optical system using tracing rays, and MATLAB is used to fit the simulation results to obtain the VGI. This method enables analysis and calculation of the VGI before fabrication of the system and provides an accurate technique to evaluate the effectiveness of the stray-light suppression in an optical system.