A dissecting microscope, also known as a stereo microscope, is an optical microscope variant designed for low magnification observation of a sample, typically using light reflected from the surface of an object rather than transmitted through it. It is frequently used in dissection operations due to its lower magnification ability and long working distance range of 25 to 150 mm, which enables the user to manipulate small specimens such as insects. The microscope allows the user to observe live specimens as well as perform dissections under the microscope.

The key features of a dissecting microscope include a single objective lens and two eyepiece lenses, with two separate light paths transmitting the image of the specimen to each eyepiece. The beam of light comes from above the specimen, and since we have binocular vision, our eyes see the image with overlapping field of view, which allows for the perception of depth. The result is an excellent three-dimensional image of the specimen under study.

Dissecting microscopes are often used to study the surfaces of solid specimens or to carry out close work such as dissection, microsurgery, watch-making, circuit board manufacture or inspection, and fracture surfaces as in fractography and forensic engineering. They are also widely used in manufacturing industry for manufacture, inspection, and quality control. Stereo microscopes are essential tools in entomology and are widely used by biology students to study insects and various samples.

Some stereo microscopes can deliver a useful magnification up to 100×, comparable to a 10× objective and 10× eyepiece in a normal compound microscope, although the magnification is often much lower. Great working distance and depth of field are important qualities for this type of microscope, and both qualities are inversely correlated with resolution. The higher the resolution, the smaller the depth of field and working distance.

In summary, a dissecting microscope is an optical microscope variant designed for low magnification observation of a sample, typically using light reflected from the surface of an object rather than transmitted through it. It is frequently used in dissection operations and allows the user to observe live specimens as well as perform dissections under the microscope. Dissecting microscopes are often used to study the surfaces of solid specimens or to carry out close work such as dissection, microsurgery, watch-making, circuit board manufacture or inspection, and fracture surfaces as in fractography and forensic engineering.