Which term describes the observer's lens you look through in a microscope?

• A. Ocular
• B. Objective
• C. Nosepiece
• D. Condenser

Answer: (A)

The observer’s lens you look through is the ocular, or eyepiece. This is the part at the top of the microscope that you place your eye against, and it works with the objective lens to magnify the specimen. The objective lens, located on the rotating nosepiece, forms the initial enlarged image, and the ocular provides additional magnification—so you get the total magnification you see. For example, a 10x ocular combined with a 40x objective gives about 400x magnification. The nosepiece holds the various objectives and rotates to change magnification, while the condenser beneath the stage focuses light onto the specimen to improve brightness and contrast. So the term for the lens you look through is the ocular.