Around 1890, the American biologist and zoologist Horatio S. Greenough introduced a design principle for optical instruments which is still used by all major manufacturers today [1-3]. Stereo microscopes based on the “Greenough principle” deliver genuine stereoscopic images of a very high quality. In the late 1950s, Bausch & Lomb, presented its StereoZoom® Greenough design with a groundbreaking innovation: a stepless magnification (zoom) changer . Almost all modern stereo microscope designs are based on a zoom system. In 1957, the American Optical Company introduced a stereo microscope with optics based on the telescope or CMO (Common Main Objective) principle 千亿体育官网. This type of stereo microscope was soon offered, in addition to the Greenough type, by all manufacturers due to its modularity and high performance.
a stereo microscope can be a big investment, therefore, the selection process should be taken very seriously. to get the most out of a microscope, users should ask themselves the following questions:
- Does it involve screening and sorting?
- Is any sample manipulation needed?
- Is documentation necessary?
- Is high resolution more important than long working distance or the other way around?
- When it comes to using the microscope for many hours, it is important to consider ergonomic accessories as they can prevent repetitive strain injuries.
- Depending on the number of different users, it is advisable to have a microscope which can be adjusted to the preference of each user.
- Modular solutions may look like a higher investment, but in the long run they will save money thanks to their versatility, ability to accommodate different users, and large variety of add-ons and accessories.
- Users who tend to work at the same magnification don’t require a large zoom range.
- If the workflow requires search, find, and sample manipulation, then it may be useful to have a large zoom range to go from low to high magnification.
- At the same zoom magnification, a bigger or smaller object field can be seen, depending on the eyepieces. A larger object field allows users to maintain a better orientation on the sample.
- A larger working distance means a greater distance between the top of the sample and the objective’s front lens, allowing for easier handling of the sample during use.
- Higher NA results in higher resolution, but usually reduced depth of field.
- The FusionOptics technology combines high resolution with more depth of field.
- Plan optics: Correction for image flatness over the entire object field which is useful for all applications.
- Achromat (achromatic) optics: For applications where true color reproduction is not important and mainly geometrical features are assessed.
- Apochromat (