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A dissecting microscope, also called a stereo or stereoscopic microscope, is a low-power microscope that gives a three-dimensional view of a specimen. According to the Meiji Techno EMZ instruction manual, “the whole point of stereoscopic microscopes” is that the observer sees the object in three dimensions and can perceive height and depth on the specimen. This page labels the parts of a zoom stereo microscope, explains what each one does, and sets out the stand differences, the setup sequence and the care rules that the manufacturers’ own manuals give.
Who uses it: anyone who needs to inspect or work on a specimen that is visible to the naked eye and has real height, such as a bench scientist examining an opaque object under incident light or a semi-transparent one under transmitted light.
What a dissecting (stereo) microscope is
The zoom stereo microscopes described in the Meiji and Olympus manuals have a binocular head, an objective, a focusing stand and a light source. The Meiji EMZ series, for example, carries a zoom control labelled from 0.7X to 4.5X, and Meiji describes the instrument as useful in material examination and quality control. For compound-microscope optics see compound microscope optics.
Dissecting stereo microscope parts, labeled
The labels below follow the nomenclature in the Meiji EMZ manual, with notes from the Olympus SZ-series instructions where they add a handling detail. This is a text list; match each name to the instrument in front of you.
| Part (as labeled) | What it does |
|---|---|
| Eyepieces with eyeshields | The lenses you look through; one per eye. Keep them seated in the body when the instrument is not in use so dust cannot fall on the internal optics (Meiji). |
| Diopter adjustment ring | Lets each eyepiece be focused separately for the right and left eye (see the setup steps below). |
| Zoom control knob (or ring) | Changes magnification continuously; on the Meiji EMZ the scale reads 4.5X to 0.7X. On the Olympus SZ models, never turn the right and left zoom knobs in opposite directions. |
| Objectives | The lens system at the specimen end of the zoom body. |
| Trinocular photo tube with lever | On trinocular models, a lever switches the image from one eyepiece up to a camera while the other eyepiece stays available for viewing. |
| Focusing knob | Rack-and-pinion fine focus on the stand. |
| Clamp screw and pillar collar | On pole-type stands, loosen to slide the whole focus assembly and zoom body up or down the pillar for rough focus, then re-tighten. |
| Stage plate and stage clips | The surface that holds the specimen. Meiji supplies a reversible black and white plate and, on transmitted-light stands, a clear glass plate. |
| Incident illuminator | Lights the specimen from above, for opaque specimens. |
| Base with transformer and transmitted illuminator | Lights the specimen from below through the glass stage plate. |
| Selector switch | Chooses the lighting: I for oblique (incident), T for transmitted, IT for both at once. |
| Dimmer switch | Adjusts illumination brightness. |
Stand and illumination types
| Type | Typical use | Key difference | Source |
|---|---|---|---|
| Pole-type stand | Specimens of varying size and height | Two-stage focusing: rough focus by sliding the focus assembly on the pillar, fine focus by rack and pinion. | Meiji EMZ manual |
| Rigid arm stand (except the extendable ABE) | Specimens within a smaller height range | Rack-and-pinion focusing only, so the range of specimen sizes and depths is “somewhat less” than on pole-type stands. | Meiji EMZ manual |
| Incident (I) lighting | Opaque specimens | Light falls on the specimen from above. Use the black/white stage plate. | Meiji EMZ manual |
| Transmitted (T) lighting | Semi-transparent specimens | Light passes up through the clear glass stage plate. | Meiji EMZ manual |
| Both (IT) | Combined lighting | Oblique and transmitted light are on at the same time. | Meiji EMZ manual |
Choosing a stage plate: Meiji states that if the specimen is semi-transparent, use the glass plate with transmitted illumination on; if it is opaque, use the black/white plate. The Olympus SZ instructions add that the black side suits white or brightly colored specimens because it gives more contrast.
Setup: interpupillary distance and diopter adjustment
Set the interpupillary distance
Move the eyetubes in or out until the distance between eyepiece centers matches the distance between your pupils. When they match, you see one central image. The Meiji manual shows an adjustment span of 54 to 74 mm. For posture and eyepiece height over long sessions, see microscope ergonomics.
Make the image stay sharp through the zoom range
The Meiji manual gives this sequence so focus holds across the whole zoom range and both eyes see equally sharp images:
- Turn the zoom control to the highest power, 4.5X on the EMZ, and focus sharply on the specimen.
- Turn the zoom to the lowest magnification. Do not touch the focusing controls.
- Looking with the right eye through the right eyepiece, turn its diopter ring until the image is precisely in focus.
- Do the same with the left eye and the left eyepiece.
The fused image should then be uniformly sharp throughout the zoom range without refocusing.
Care and common mistakes
- Leaving it uncovered. Both manufacturers say to cover the instrument with the dust cover when not in use (Meiji; Olympus). Olympus adds that it should be stored in an area free from moisture to prevent rust and kept away from direct sunlight, high temperature, humidity, dust and vibration.
- Removing eyepieces and leaving the tubes open. Meiji says to keep the eyepieces in the body at all times to stop dust reaching the internal optics.
- Pressing hard on lenses. Meiji advises cleaning exposed lens surfaces with pressurized air, a soft brush or a clean soft cloth, and warns that too much finger pressure may damage lens coatings. Painted or plastic parts get a cloth with water and a little detergent.
- Using solvents carelessly. The Olympus instructions describe cleaning glass with gauze moistened with an ether and alcohol mixture, call these solvents highly flammable, require a well-ventilated room away from sparks, and say not to use organic solvents on plastic parts.
- Adjusting the internals. Meiji: do not attempt adjustments to the internal optics or mechanics. Olympus: never disassemble.
- Forcing the controls or handling roughly. Olympus describes the microscope as precision equipment to be handled without abrupt movement or impact.
- Changing a lamp while connected. Meiji says to disconnect the illuminator from the mains before replacing a bulb.
FAQ
What are the main parts of a dissecting microscope?
Eyepieces with diopter rings, a zoom control, objectives, a focusing knob on a pole or rigid arm stand, a stage plate with clips, and incident and/or transmitted illumination controlled by a selector switch and dimmer. The labeled table above lists each with its function.
What is the difference between a dissecting microscope and a stereo microscope?
Both terms are used for the same kind of instrument. The Meiji and Olympus manuals cited on this page both describe it as a zoom stereo microscope.
Does it give a three-dimensional image?
Yes. Meiji states the observer sees the object in three dimensions and can perceive height and depth on the specimen.
Which light should I use?
Incident light for opaque specimens, transmitted light through the glass plate for semi-transparent ones, per the Meiji manual.
Sources
- Meiji Techno, EMZ Series zoom stereo microscope instruction manual, https://xdevs.com/doc/Meiji/emz_manual.pdf, checked 2026-10-29.
- Olympus, SZ30/SZ40/SZ60/SZ11 zoom stereo microscope instructions, https://www.alanwood.net/downloads/olympus-sz30-sz40-sz60-sz11-instructions.pdf, checked 2026-10-29.
Related reading: microscope objective selection, calibrating a microscope with a stage micrometer, what a microscope is in a research lab.
