Inventive Genius: The Microscope
In 1590, the Dutch father and son duo of Zacharias and Hans Janssen, eye-glass makers by profession, pieced together a contraption of a tube with multiple lenses placed in it, and discovered that one can see objects in a much larger size if viewed through their contraption. This is perhaps the first recorded instance of a microscope (and, probably a telescope too).
The discoverer of the cell, Robert Hooke also made his own version of the microscope, probably the first compound microscope, in 1655 AD. He published a book titled ‘Micrographia’ ten years later, describing the wonderful world he observed through his invention.
Also given credit is Antonie van Leeuwenhoek. Leeuwenhoek was a trader by profession and an amateur lens grinder. It was he who invented the microscope as we know it today, replete with small glass lenses mounted in brass, and screws and pins to focus the sample under observation.
Leeuwenhoek was a master in grinding lenses and created powerful lenses to the order of 270X-300X, that could magnify much more than what was ever possible earlier. His microscopes were instrumental in his discovery of blood cells, bacteria and sperms. Leeuwenhoek’s microscope design was copied and/or improved upon by many including Robert Hooke.
Microscopes opened up a totally new world - that of structures too small to be seen by the human eye. And from the basic microscopes of the 16th and 17th centuries to the advanced electron and confocal microscopes of today, the journey has been nothing short of miraculous.
In the 1870s, minor improvements in optics and design were made, but there was a general period of lull for the following two centuries. The next major milestone was Joseph Lister’s effort in 1830 which lead to lenses having reduced chromatic effect. Lister showed that combining multiple weak lenses at specific distances reduced blurring and spherical aberration due to refraction of light. And thus was born the ‘achromatic lens’ as we know it today. Achromatic lenses could resolve up to one micron.
Making lenses and microscopes had now become a flourishing business, and Carl Zeiss in 1847 started making microscopes in the town of Jena in Germany.
It was soon established that using white light, one cannot resolve objects that are situated closer than half the wavelength of the light. As white light has a wavelength of 550 nm, no two objects situated 275 nm or lesser apart can be resolved. The solution was to use light of a shorter wavelength for illumination, and Richard Zsigmondy was the first to actually do it, creating the first ever Ultramicroscope. This achievement fetched him the Nobel Prize in Chemistry in 1925.
The next two Nobel Prize winning efforts for improved microscopes were for the Phase Contrast microscope and the Electron microscope, which were discovered in 1932 and 1931 respectively. The 1953 Nobel Prize in Physics was given to Frits Zernike, who invented the phase contrast microscope. Using phase contrast, one could study even colorless transparent objects.
The 1985 Nobel Prize in physics was awarded to Ernst Ruska, co-inventor of the electron microscope, which went a step ahead of the original ultramicroscope and used electrons as a source of light, enabling atomic-scale resolutions and magnification up to 1,000,000X.Red White Blood cells
Indeed, one can view in three dimensions, using the scanning electron microscope, sub-cellular ultrastructures in tremendous detail. The inventors of the scanning electron tunnelling microscope, Gerd Binnig and Heinrich Rohrer were the recipients of the Nobel Prize for Physics in the subsequent year, 1986. 1. A periscope is an instrument for observation usually used in___. a) a ship b) a submarine c) an aircraft
2. Who usually uses a stethoscope? a) a plumber b) a mechanic c) a doctor
3. The largest telescope in the world is located in____. a) Canary islands b) Texas c) Hawaii
4. What is used to examine a ship’s hull while it is underwater? a) periscope b) microscope c) aquascope