Terahertz graded refractive index lenses for biomedical systems for human disease diagnostics

Terahertz (THz) waves have revolutionized healthcare, opening up new horizons in non-invasive imaging, diagnostics, and therapy. They enable high-precision imaging of biological tissues without ionizing radiation, making them a safer alternative to X-rays and CT scans. The THz frequency range can be used to study the properties of biological molecules, including DNA, proteins, and drugs, which helps in the development of new drugs and treatments. THz imaging systems require compact, affordable, quickly manufactured, replaceable components with controlled characteristics, particularly lenses. The aim of the study is to develop a method for producing inexpensive compact flat lenses with a gradient refractive index using additive technologies, in particular extrusion 3D printing, for use in terahertz imaging systems for the diagnosis and treatment of socially significant human diseases, including oncological diseases. method of creating terahertz graded-index lenses by changing the extrusion coefficient during 3D printing is described, and the distribution of the terahertz radiation field in the focus of the studied lenses is demonstrated. The dependences of the focal length of the gradient lenses on the thickness and diameter of the lens are shown. The proposed and described method based on additive technologies will allow the production of lenses with a gradient refractive index, which can be used for innovative terahertz medical imaging systems of the new generation for the diagnosis and therapy of socially significant human diseases, such as oncology, diabetes, corneal diseases, burns, etc. due to the speed of production, reduced weight, compactness, absence of spherical aberrations, the ability to adjust the focal length, controlling the gradient of the refractive index inside the lens, as well as the thickness and diameter of the lens.