Imagine how your world would look line without computers, ipods, television, cell phone. The history behind the component that make these “part of life” gadgets dates back centuries. Invention of electric battery Alessandro Volta in 1800 was the most important event that led to the first device that used electricity as the power source. Electronic devices need electrical power supply.
Electric bulb may be regarded as the first electronic device that used electric current as power source. Humphrey Davy invented incandescent light bulb in 1809 though Thomas Alva Edison is regarded as the inventor of modern light bulb.
Most significant invention crucial to modern electronics was cathode ray tube which was invented by Karl Ferdinand Braun in 1879. cathode ray tube is an evacuated glass casing with electron gun. This concept led to the first current directing electronic device, the vacuum tube. British John A. Fleming in 1904 made the first vacuum tube as a known as a “valve” as it allowed current to travel in one direction only. A stride in development vacuum tube was made by De Forest found out that by placing a metal grid with between two electrodes of a vacuum tube and passing a weak current into this grid. De Forrest noticed that by changing the voltage on this grid he could control flow of a powerful current through the tube. He also realized that amplification of current between the electrodes is possible as the weak current applied to this grid can increase current in the vacuum tube by an amount greater than its value. De Forest called it an “Audion” which was know as triode in after 1912. This discovery was most significant milestone in modern electronics.
Vacuum tubes found its way to electronic devices like radio, televisions and computers used during that time. However, vacuum tube had a significant drawback. They had a short life and often needed frequent replacements. These tubes would burst out occasionally and get heated very quickly. They were bulky in size. This was the reason why old computers were very large in size. The operating cost for these devices was high.
A revolutionary concept of semiconductor which was under research for decades finally surfaced out in 1940’s changed the electronic world forever and paved way for modern electronics. A semiconductor is an insulator converted to a conductor by adding impurities. This process of adding impurities is called “doping” .Carbon, Silicon and Germanium are the ideal candidates for semiconductors. Doping with Boron and Gallium produces a “p-type” semiconductor whereas doping with Phosphorus and Arsenic produces “n-type” conductors. It is the junction, called the pn-junction, between these doped crystals which allow current to flow in one direction only and acts as a diode. A transistor can be created by having p and n type doped crystals sandwiched between n or p type crystals respectively to create npn or pnp type transistors. These transistors and diodes were superior compared to the old vacuum tubes as these generated less heat, were more durable and were much smaller size compared to their old counterparts. In 1947 Bell Labs invented transistor for its first commercial use is in products for the hearing impaired.
Another major breakthrough in the world of electronics happened as result of invention of integrated circuit. In 1958 Jack Kilby of Texas instruments made a first integrated circuit with transistors and capacitors and used silicon to complete the circuit between the electronic components. A decade later, In 1970 Gilbert Hyatt developed first microprocessor. A microprocessor is a collection of a large number of integrated circuits. Intel Corporation created the first commercially viable microprocessor in 1971. Microprocessor had a considerably small size which made it easy to incorporate in modern electronic devices.
Today, Microprocessors are used in all modern electronic gadgets. From gaming to life saving devices electronics is now a key component. We can not imagine a world without them. It would be safe to say electronics will continue to remain the mankind’s most effective tool to meet the future challenge.