Design and theoretical analysis of the image-side telecentric zoom system using focus tunable lenses based on Gaussian brackets and lens modules

•This paper presents the design method of the image-side telecentric zoom system with four focus tunable lenses (FTL) and a moving aperture stop (STO) by applying gaussian brackets and lens modules. Compared to conventional mechanical zoom telecentric systems, this system greatly reduces the mechanical moving group, thus reducing the structural complexity of the system, greatly reducing mechanical vibrations and misalignments, which is a great advantage for telecentric systems where the application scenario requires high accuracy, and makes it easier to achieve control of the total length.•The work we study mainly concentrate on improving gaussian brackets, establishing screening method used in solution space, using the lens module method design the telecentric zoom FTL system, and extending the lens module combination method applicable to the lens group contains an FTL.•We believe that this article is suitable for publication in optics and lasers in Engineering. The design method of the telecentric zoom FTL system proposed in this paper is simple in principle, easy to understand and has excellent effectiveness when applied to the actual design process, which is an important reference for the development and research of subsequent telecentric zoom FTL systems.