Incandescent bulbs work very differently. Rather than converting electrical energy straight into light, incandescent bulbs use heat - and a lot of it! There is so much heat energy in the filament of an incandescent bulb that the metal inside it lights up very brightly.

The field of view in a microscope is defined as the diameter of the illuminated circle which is seen through the eyepiece. With an increase in the magnification, there is a decrease in the field of view.

The Positive/Negative (P/N) junction in the middle of an LED consists of an anode (the positive side) and a cathode (the negative side), both made of semi-conductive material.

LEDs have become the world-leading light source in recent years due to their highly efficient designs and wide-ranging capabilities, but what they are and how they work is not widely understood.

Electroluminescence is very complex, because it relies on changes to very small particles and highly technical processes.

After over 100 years of research, scientists have learned how to capture and reflect this light efficiently, so that we can see it more easily. This has made LED technology what it is today.

The difference in vision between the two eyes is corrected with the help of diopter adjustment. Through diopter adjustment, the focus of the individual eyepiece can be done so that the eyes feel comfortable while observing the sample.

The working principle of a simple microscope is that when a sample is placed within the focus of the microscope, a virtual, erect and magnified image is obtained at the least distance of distinct vision from the eye that is held at the lens.

A compound microscope is defined as the type of microscope that has more than one lens. It has a combination of lenses and two optical parts known as an objective lens and an eyepiece or ocular lens. The magnifying power of the compound microscope is given as:

There are different types of microscopes and each of these has different purposes of use. Some are suitable for biological applications, while others are used in educational institutions. There are also microscope types that find application in metallurgy and studying three-dimensional samples.

Diodes only light up if electricity passes across them in the right direction, they will not light up if they are installed the wrong way around.

The working principle of the compound microscope is that the combination of lenses enhances the magnification of the sample. The sample is first viewed as a primary image in the tube and viewed again in the eyepiece.

The depth of field in a microscope is defined as the distance from the nearest object plane in focus to the farthest plane in the same focus. In microscopes, the depth of field is very short and is measured in units of microns.

A simple microscope is defined as the type of microscope that uses a single lens for the magnification of the sample. A simple microscope is a convex lens with a small focal length. The magnifying power of the simple microscope is given as

LEDs rely on an effect called electroluminescence. This is the conversion/transference of electrical energy into visible light, by running an electrical current through a material, usually tiny human-engineered crystals.

The depth of focus in a microscope is defined as the distance between the objective lens and the sample plane. The depth of focus varies from person to person and is also dependent on the quality of focus.

In this article, there are 5 such microscope types that are discussed along with their diagram, working principle and applications. These five types of microscopes are:

The basic difference between low-powered and high-powered microscopes is that a high power microscope is used for resolving smaller features as the objective lenses have great magnification. However, the depth of focus is greatest for low powered objectives. As the power is switched to higher, the depth of focus reduces.

The scanning probe microscope has a probe tip that is mounted on the end of a cantilever. The tip is so sharp that it can move precisely and accurately across the surface of the sample scanning every atom. The tip is placed close to the surface of the sample, such that the cantilever experiences a deflection due to forces. This deflection distance is measured by the laser. The final image after scanning is obtained on the computer.

A stereo microscope works on the reflected light from the sample. The magnification of the microscope takes place at low power and hence, it is suitable for magnifying opaque objects. It is suitable for thick and solid samples because it uses light reflected from the sample. The magnification of the stereo microscope is between 20x and 50x.

An electron microscope is defined as the type of microscope in which the source of illumination is the beam of accelerated electrons. It is a special type of microscope with a high resolution of images as the images can be magnified in nanometers.

The metal used in an electron microscope is tungsten. A high voltage current is applied which results in the excitation of the electrons in the form of a continuous stream that is used as a beam of light. The lenses used in the electron microscope are magnetic coils. These magnetic coils are capable of focusing the electron beam on the sample such that the sample gets illuminated. As the flow of current increases, the strength of the magnetic lens increases. The electron beam flow is designed such that it cannot pass through the glass lens.

While the development of the light bulb was a great stepping stone in modern civilisation, this process is sadly very inefficient. Incandescent bulbs waste up to 95% of energy on heat, rather than light. As a result, many people have burned their hands changing these bulbs, while hurting their wallets in the process! On larger scales, these fixtures become quite dangerous.

A stereo microscope is defined as a type of microscope that provides a three-dimensional view of a specimen. It is also known as a dissecting microscope. In a stereo microscope, there are separate objective lenses and eyepiece such that there are two separate optical paths for each eye.

According to Which? Magazine, a household LED light fixture will save 60% in energy cost per bulb (Which Nov2017), while also lasting more than 15x as long. Those numbers speak for themselves, so with LEDs getting cheaper to produce every year, and innovations getting more and more creative, they will continue to dominate the markets.

The scanning probe microscope is defined as the type of microscope that finds applications in industries where the examination of the specimen is done at the nanoscale levels. The study of a specimen’s properties, its reaction time and its behaviour when stimulated can be done with the help of a scanning probe microscope.

Electrons travel across the negative cathode into the positive anode, and when they undergo this change, their energy-potential also changes. These electrons are filling “electron-holes” on the other side of the junction, which allows an energy-transfer. When this is correctly balanced, the energy change emits a light particle called a photon, with the same energy as that which travelled across the P/N junction.