What are Objective Lenses on a Microscope?

objective lenses

Several types of different objective lenses are available.

Objective lenses are the optic components of microscopes that take light from the object being observed, focuses the rays and then produces the image.

What are types of objective lenses?

Although all four objective types will correct for achromatic errors (color errors), there is no “achromatic” in the name of “semi plan”, “plan”, and “semi-APO”. The difference between the lenses is the focusing area which can be seen from the eyepieces when using the objective lenses. The difference at the low power lenses is smaller than at the higher 40/60/100x lenses.


These lenses are built-up out of one or two lenses and has about 60% of focused area across the center.


Semi-plan objectives can either be built-up out of two lens element achromats or three or more element apochromats and has about 80% of focused area across the center. EPL on objectives stands for Eco Plan or economical plan and
is comparable to semi plan.


A plan objective corrects better for color and spherical aberration that either the semi plan or the achromatic objective. Plan objectives have a flat field around the center of close to 100% of the image and gives flatter fields and slightly higher resolving power (details). Plan objectives are supplied to middle and high end laboratories.


These are additional lenses built-in to improve corrections even further, and therefore they give the most superior image. While they give the best image, they also are the most expensive. They are used by high end users where extreme quality of images and details are required.

View our complete line of microscopes

Need a compound microscope

Related Articles

How Do They Rank? Simple Microscopes vs Compound Microscopes

What is a Compound Microscope?

Don’t forget to sign up for our blog to receive the latest posts right to your email. Find the form at the top of the page to the right.





Be the first to comment on "What are Objective Lenses on a Microscope?"

Leave a comment

Your email address will not be published.


This site uses Akismet to reduce spam. Learn how your comment data is processed.

%d bloggers like this: