Stereoscopic Microscope: Design, Working and Uses

Microscope applications are not new to scientific researchers, biologists, health experts and many other professionals, for whom studying minute objects is part of work. In addition to simple and compound ones, that we have used in school and college days, several modifications of these optical tools have been developed for detailed scientific studies.

Each of them has unique features that allow users to get high-end images. An example of such advanced tools is the stereoscopic microscope, which is configured with specific lenses to create different light paths.

Stereoscopic microscope, or simply stereo microscope, is an optical tool, different from other types, in instrumentation and working principles. As we all are aware, the regular device has one eyepiece and one objective lens.

In contrary to this, the working of a stereoscopic device involves two set of optic systems, which in turn result in formation of two different light paths. The objective of this lens configuration is to create a clearer three-dimensional image.

Thus, in comparison to other devices that give two-dimensional images, the stereoscopic device is superior, in terms of creating a better three-dimensional image.

A stereoscopic microscope is a binocular magnifying tool, used for viewing a three-dimensional (3D) image of the specimen. The working principle of this scientific tool is nearly similar to other magnifying devices. In a compound optical instrument, the magnified image of the sample under observation is formed by transmitted illumination.

In simple terms, light passes through the specimen and then reaches the eyes. On the other hand, a dissecting one works by means of reflected illumination. Over here, light doesn't transmit through the object, but it is reflected back to form a 3D image of the sample.

The size of this microscope is larger than that of a compound one, with the former measuring about 1-2 feet height. Coming to its parts, it has two ocular lenses or eyepiece lenses, and one objective lens. They are connected by a body tube, which can be lowered or elevated to give clear images.

The rotating objective is located below the movable eyepiece, and above the stage plate. Based on the model, the lenses are made up of plastic or glass. While some of the models are configured with a lighting source, others require external supply of light. There are also adjustment knobs for regulating light and focus.

The main uses are attributed to examining whole objects with depth perception, but not a part of the object. As aforementioned, the magnified image created by this optical tool is through reflected illumination. Considering this, the major application of this is viewing opaque or thick objects, in which transmission of light is not possible.

Say for instance, rock samples, coins, flowers, insects and circuit boards are very difficult to observe under a compound microscope. The reason being inability of light to pass through the slide specimens. In such cases, a stereoscopic device is used to get realistic images of the objects.

While using a stereo microscope, you need to use both eyes simultaneously. Very often, this particular type of laboratory equipment is known as dissecting microscope. The reason is the frequent use of this laboratory tool for laboratory studies that call for close examination of a specimen, like dissection, surgical procedure, and other applications.

However, their magnification power is low, with a maximum magnifying power of 10X to 40X. Thus, very small or minute specimens that require magnification to hundred times or more are viewed under compound magnifying devices.

With a stereo microscope, there is less issue for eyestrain as you do not need to squint your eyes for viewing the images. Nowadays, it is used in association with a computer, that is programmed with three-dimensional image viewing feature. The important images observed are captured by a camera, which are then stored in the computer for later use. Thus, instead of viewing them individually through the eyepieces, the images can be studied by many people at a time.