A tool designed to compute the angle of incidence at which light passing from a denser to a rarer medium is refracted at an angle of 90 degrees. For example, such a tool might accept the refractive indices of two interacting media as input and provide the critical angle as output. This angle is crucial for phenomena like total internal reflection.
Determining this specific angle is fundamental in optics and has various applications, from the design of optical fibers for telecommunications and medical imaging (endoscopes) to the understanding of natural phenomena like the brilliance of diamonds. Historically, understanding this concept has been essential for advancements in fields ranging from microscopy to astronomy.