“Inverted microscopes are flipped around, with the objectives on the bottom and the light on the top. This lets you see samples inside beakers, flasks, and petri dishes that would not normally fit on a compound microscope stage.”
What does calling a microscope “inverted” mean?
Although most microscopy terminology sounds foreign or technical, this is one term that really means exactly what it says. An inverted microscope is a microscope with the objectives on the bottom of the stage, and the light source/condenser at the top of the microscope. The eyepieces are usually off in the same position towards the back of the microscope. Not much else to it–otherwise, it functions exactly the same as a compound microscope.
What benefits does an inverted microscope offer?
Having the light source above and the objectives below means that your sample medium can be much larger than a simple slide. Your working distance limitation of the objectives when coming from above is gone entirely, as is the need to move the stage vertically to focus, as it’s the objective turret itself that moves to adjust for focus. Your sample doesn’t move, unless you have a mechanical stage and need to scan around the sample.
Common uses for an inverted microscope are viewing bacteria or cell cultures that are bred in larger environments, such as a petri dish, beaker, or flask.
How does an inverted microscope work?
While understanding of a compound microscope’s basics essentially explains how an inverted microscope works, here is a simple diagram to help the visually inclined learners like myself explain the path of light in an inverted microscope.
Typically I include an image of what you would expect to see from the microscope type, however in this case, it is no different than a brightfield compound microscope.
Are there more advanced applications for an inverted microscope than simple brightfield?
Yes, there certainly are. Inverted microscopes can be a great deal of specialized microscopes as well, such as metallurgical, phase contrast, and fluorescent. They cannot, however, be darkfield microscopes, as the condenser is typically very far away from your sample, and darkfield condensers in typical compound microscopes need to be close to the sample for the oblique angled lighting to take effect while still entering the objective.
Inverted metallurgical microscopes are of benefit when the sample size is too large or thick to fit on a traditional stage. Often industrial manufacturers can use such a unit for checking for faults on larger parts, where even a small fault can cause complete failure of their product (such as in the aerospace industry).
Fluorescent inverted microscopes are commonplace in research labs in esteemed universities and private laboratories. Cell cultures and tissue cultures typically need larger storage media to work, while also needing very specialized dyes that emit colored light when a specific wavelength of light hits the sample (called “exciting” the sample). An inverted fluorescent microscope basically takes the EPI illumination from a metallurgical microscope and filters it in such a way where a specific wavelength of light hits the sample, excites it, and the corresponding light is what becomes visible in the microscope.
I’m still a bit confused but I know I need an inverted microscope. Can you help me find a basic unit?
I’d be happy to help. If all you have is a need for a basic compound inverted microscope without all of the bells and whistles of the more advanced kinds, here is one I’ve tried and enjoyed using.
AmScope’s IN200B
AmScope’s IN200B is probably the most cost effective inverted brightfield compound microscope on the market. It doesn’t have anything fancy or advanced, but will get the job done for minimal cost if all you need is brightfield.
To check this unit out, you can access more information from here or the image above: IN200B
Motic’s AE2000
While I don’t typically review or use Motic products due to their relatively high price point, I can’t argue with the quality of the AE2000 when I received it. It has extremely high quality optics (Color Corrected Infinity System optics), a nice, bright halogen light to maintain highest color integrity, and a compact yet flexible design.
To give this beauty a try, head on over for more information at the image above or here: AE2000