The lens located at the object end of a microscope tube. Many types of objectives are used in microscopy; simple achromats and color-corrected apochromats are popular choices.
SPHERICAL VS. ASPHERIC LENSES
HOW THEY’RE USED IN IMAGING APPLICATIONS
Optical Lenses are often categorized by their shape. Two common surface shapes are spherical and aspherical. Each offers unique characteristics that make it suitable for different use cases.