Students, hobbyists, and experts from across a range of industries all use advanced, high-tech microscopes as an integral part of their daily routines. But what are these devices and how do they work?
Let’s take a look.
A Compound Microscope is a microscope that consists of two or more double convex lenses fixed in the two extremities of a hollow cylinder.
The upper lens is the eyepiece and the lower lines is the objective. The cylinder is mounted upright on a screw device that permits it to be raised or lowered until the object is in focus and until a clear image is formed.
When an object is in focus, a real inverted image is formed by the lower lens at a point inside the principal focus of the upper lens. This image serves as an object for the upper lens that produces another image larger which is visible to the observer.
A Stereo Microscope is a lower-powered microscope instrument that features a large stage for closer viewing of the non-microscopic world.
With stereo microscopes, tiny things became large. For example, the flaws in gemstones and coins will become obvious.
There are inexpensive models available for children and students, while higher-end models that provide zoom, improved optics, and enhanced lighting are available for professional use.
Electron Microscopes are microscopes that use electrons, rather than visible light, to produce images. Electron microscopes can magnify very small detail with high resolving power.
They were invented by German physicist Ernst Ruska. Since then, electron microscopes have evolved into a vital tool within the medical field.
The Digital Microscope is the newest innovation of microscopy that uses a digital camera for imaging.
They utilise USB technology to produce live images viewable on a computer monitor, and make use of an inverted lens design so that specimens of variable sizes and shapes can be viewed with little or no preparation.
A rotatable lamp also enables the illumination of opaque specimens by reflected light.
A Video Microscope is similar to a digital microscope. They are powered through the use of digital cameras that offer many features specifically designed to suit microscopy.
The video and cameras used in video microscopes offer high resolutions coupled with high sensitivity. All are designed for a broad range of imaging applications and excel at the rapid acquisition of low-light level fluorescence images.
However, when using these tools for fluorescence microscopy, be sure to use a microscope that has a high-quality laser excitation filter installed – ideally one that includes a narrow band pass filter – if you want to get the best results.
Scanning Tunnelling Microscopes
Scanning Tunnelling Microscopes are instruments used in scanning probe microscopy. They can view very small images of any conductive surface and inspect an area as small as 0.2 nanometers.
Using the tip, these microscopes can alter the material being investigated by manipulating its atoms. Data is then transmitted from the tip of the microscope to a computer, where the results can be analysed.
The scanning tunnelling microscope allows a scientist to visualise areas of high electron density, thereby helping them understand the position of individual atoms, where before most could only give an educated guess.
Confocal Microscopy is a great tool to get high-resolution images restructured into a 3-dimensional image of the scanned object. They can provide smooth and clear smudge-free images with different depths, and then reconstruct them to give an in-depth picture.
A computer is used in this process to allow for faster and easier image production. The use of lasers in later models of Confocal Microscopes allowed for them to be extremely accurate.