verters are found in most electronic devices and are responsible for producing data within small circuits.

How CMOS Inverters Work

CMOS inverters work like most other types of field-effect transistors, but depend on a layer of oxygen to separate electrons in the gate and semiconductor. They are made up of a power supply, voltage input terminal, gate, drain, voltage output, and PMOS and NMOS that are connected to both the gate and the drain. As low voltage is applied to the voltage input, the PMOS is turned on while the NMOS remains off, allowing electrons to flow through the gate and causing the voltage output to produce a high logic. Conversely, as high voltage is applied to the voltage input, both the PMOS and NMOS are turned on, preventing as many electrons from reaching the voltage output and causing the voltage output to produce a low logic.

Applications

CMOS inverters play a critical role in integrated circuits, including microprocessors, microcontrollers, static RAM, image sensors, data converters, and some types of transceivers. CMOS inverters are found in digital cameras, mobile devices, home computers, network servers, routers, modems, cell phones, and virtually every other electronic device that requires logic functions.

Advantages

CMOS inverters have several important advantages. For example, CMOS inverters only use electricity when they are turned on and off, resulting in very little power consumption. Consequently, CMOS inverters produce very little heat waste, making them highly efficient and usable in a wide variety of small, delicate electronic devices. Additionally, CMOS inverters have high noise immunity, which allows them to block both incoming and outgoing frequency spikes. Finally, CMOS inverters are inexpensive to mass produce.

Vocabulary:

CMOS (Complementary Metal-oxide Semiconductor inverter) – комплементарный металл-оксидный полупроводниковый инвертор

PMOS – положительный металл-оксидный полупроводник

NMOS – отрицательный металл-оксидный полупроводник insulating layer – изолирующий слой

field-effect transistors – полевой транзистор

voltage input terminal – входная клемма напряжения data converters – преобразователи данных transceivers – приемопередатчики

frequency spikes – скачки частоты

Lasers

The name LASER is an acronym for Light Amplification by the Stimulated Emission of Radiation. It is a device that emits a beam of light through a process

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called optical. It distinguishes itself from other sources of light by emitting light in a spatially and temporally coherent manner. Spatial coherence keeps the beam within a narrow and tight path over long disances. This allows the energy generated to be used in applications such as laser cutting and laser pointing. Having temporal coherence amplification means that can emit light within a narrow spectrum to generate a light beam of a specific color.

In 1917, Albert Einstein first theorized about the process which makes lasers possible called "Stimulated Emission." He detailed his theory in a paper titled Zur Quantentheorie der Strahlung (On the Quantum Theory of Radiation). Today, lasers are used in a wide range of technologies including optical disk drives, laser printers and barcode scanners. They are also used in laser surgery and skin treatments as well as cutting and welding.

Before the Laser

In 1954, Charles Townes and Arthur Schawlow invented the maser (microwave amplification by stimulated emission of radiation) using ammonia gas and microwave radiation. The maser was invented before the (optical) laser. The technology is very similar but does not use visible light.

On March 24, 1959, Townes and Schawlow were granted a patent for the maser. The maser was used to amplify radio signals and as an ultra-sensitive detector for space research.

In 1958, Townes and Schawlow theorized and published papers about a visible laser, an invention that would use infrared and/or visible spectrum light. However, they did not proceed with any research at the time.

Many different materials can be used as lasers. Some, like the ruby laser, emit short pulses of laser light. Others, like helium-neon gas lasers or liquid dye lasers, emit a continuous beam of light.

The Ruby Laser

In 1960, Theodore Maiman invented the ruby laser considered to be the first successful optical or light laser.

Many historians claim that Maiman invented the first optical laser. However, there is some controversy due to claims that Gordon Gould was the first and there is good evidence backing that claim.

The Gordon Gould Laser

Gould was the first person to use the word "laser." Gould was a doctoral student at Columbia University under Townes, the inventor of the maser. Gould was inspired to build his optical laser starting in 1958. He failed to file for a patent his invention until 1959. As a result, Gould's patent was refused and his technology was exploited by others. It took until 1977 for Gould to finally win his patent war and receive his first patent for the laser.

The Gas Laser

The first gas laser (helium-neon) was invented by Ali Javan in 1960. The gas laser was the first continuous-light laser and the first to operate "on the principle of converting electrical energy to a laser light output." It has been used in many practical applications.

Hall's Semiconductor Injection Laser

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