A slit lamp is a specialized microscope used in ophthalmology to examine the structures of the eye, particularly the anterior segment, which includes the cornea, iris, lens, and the anterior chamber. It combines a high-intensity light source with a binocular microscope, allowing doctors to view the eye in great detail. The slit lamp's light can be adjusted to form a narrow beam (or "slit") to enhance the visibility of different layers of the eye.