The inherent dispersion of the glass utilized in lens construction necessitates applying various techniques to eliminate aberrations. Prior research has traditionally concentrated on single-spectrum applications, targeting either the visible or infrared region. In this study, we designed and conducted numerical simulations of an achromatic lens designed for the UV-visible spectrum, employing unconventional materials such as silicon nitride (Si3N4) and aluminum oxide (Al2O3). The Si3N4 serves as the equivalent of Flint glass, offering a high refractive index and a relatively lower Abbe number. Its transparent window extends from the deep ultraviolet (UV) range and covers the entire visible spectrum. Conversely, Al2O3 is well-suited for use as crown glass, given its lower refractive index than Si3N4 and a higher Abbe number, and Al2O3 remains transparent from the UV region till the mid-infrared region. Combining these two materials should yield an achromatic lens with eliminated chromatic aberrations. Therefore, lens design started with the achromat equations, and further optimizations were done using the ray tracing software Opticstudio Zemax. The Seidel diagram and focal shift graph offered empirical validation of our study's complete reduction of aberrations, and good focusing efficiency was achieved. The operational wavelengths in our study encompass a range from 360 nm to 633 nm, encompassing both the ultraviolet and visible spectra. Our work may apply to futuristic broadband imaging systems, collimators, and spectrometers.
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