Fluorescence microscopes are basically an optical microscope that uses fluorescence or phosphorescence to produce an image of a specimen. These types of microscopes hold special importance in the study of biology. Vacker Africa supplies all types of Microscopes in South Africa, Tanzania, Congo, Nigeria, Chad, Djibouti, Morocco, Egypt, Zimbabwe and many more.
What is fluorescence and phosphorescence?
Fluorescence is a well-known property of objects in physics. Generally, it refers to the property of the object that reflects light of longer wavelength when they absorb light of short wavelength. The examples of light with short wavelength are ultraviolet rays and X-rays which are both invisible to the naked eyes.
What is phosphorescence?
Phosphorescence is quite similar to the fluorescence but in this case, the emission of the light from the object continues for a longer period of time even after the excitation of the light ceases.
The phenomenon of fluorescence was first observed by a very well-known British scientist named Sir George G. Stokes. He observed that when a mineral known as fluorspar was excited with ultraviolet rays (which have a shorter wavelength than the visible light) they emit red light. He was quick to notice that the wavelength of the emitted visible light had loner wavelength than the ultraviolet rays. Thus, he termed the word fluorescence in the year of 1852. Although fluorescence remained a known property in science in the nineteenth century its use came into use in microscopy only in the twentieth century.
Today, fluorescence microscopes are an essential part of every biological laboratory as well as biomedical sciences. These microscopes have helped the researchers identify cells and their parts to sub-microscopic level. Fluorescence microscopes are so precise that they can even reveal the presence of a single molecule which is not imaginable with a conventional optical microscope. Researchers are capable of identifying various target molecules with the help of multiple fluorescence labeling. The use of fluorescence microscopy in the field of biology is expanding exponentially. The users are capable of identifying cellular components with precise specificity. Fluorescence microscope has brought revolution in the medical field by helping us to learn about various types of antibodies and impurities in the cell.
Fluorescence light sources
The problem with fluorescence microscope is that the emission level is very low and likewise the level of photons that reach the camera detector or the eye of the user is very low. Hence it is very important to create enough light excitation in the specimen to be observed. For such purpose one can use discharge lamps that are known to produce sufficient light excitement. Most of the researchers prefer mercury burners with power that ranges from 50 watts to 200 watts. Use of xenon burners is also pretty common. These lights sources required to be powered by external current capable of producing enough start-up power that can ignite the burner. The power supply also requires a timer to keep note of the time for which the burner has been operating. The lamps generally have a life expectancy of only 200 to 300 hours. Use of the lamps for more than their expected life should be avoided.