The Lieberkühn microscope is a type of optical microscope designed for enhanced illumination of specimens. It features a unique built-in mirror system that directs light onto the sample, allowing for clearer and brighter images. This design is particularly useful for observing transparent or semi-transparent materials. Developed by Johann Heinrich Lieberkühn in the 18th century, this microscope is often used in biological and medical research. Its ability to provide high-contrast images makes it valuable for studying cellular structures and other minute details in various specimens.