Microscopes and imaging: a brief independent guide

Microscopes are not new technology. The first magnifying glasses were used by the Romans in around 100 AD, and by the end of the 16th century these lenses had been put together to form a rudimentary microscope. By the end of the 17th century, Anthonie van Leeuwenhoek, the so-called ‘Father of Microscopy’, had discovered single-celled organisms, bacteria, spermatozoa, blood cells and the structure of muscle fibre. Today, optical microscopes remain a vital part of a huge range of industries and can be found in hospitals and laboratories across the world.

Most microscope users will be familiar with the products of the ‘big four’ manufacturers – Leica, Nikon, Olympus and Zeiss. However, there are also credible brands with which people may not be so familiar, and these include Japanese manufacturer Meiji and Chinese company Motic. In my opinion, most people would struggle to tell the difference between manufacturers with regard to the quality of optics found on modern microscopes. So, assuming that the microscopes all perform well at an optical level, the main customisable aspects are objective lenses, ergonomics, light sources (transmitted and/or fluorescence) and imaging.

Objectives
Plan fluorites are excellent, high-quality optics suitable for virtually all applications. Most microscope manufacturers offer at least three grades of objective lens: achromat, fluorite and apochromatic. The differences are essentially how well corrected each is for spherical and chromatic aberration, and the resolving power of the lens. Any objective marked Plan or Pl is also corrected for field curvature and produces a much flatter image. In the real world, Plan fluorite objectives are suitable for all but the most demanding of applications. If, for example, you are performing optical sectioning and 3D reconstruction at high magnification, then apochromatic objectives are recommended.