The photodiode is the p-n junction device. It is also considered as the photo-detector. This type of diode generally absorbs the light energy. Then it converts that light energy to the electrical energy for use. These diodes are sensitive to proton radiation. But these systems work like a solar cell in the reverse bias condition.

In this article, today we are going to discuss the different applications of photodiodes in detail.

What is Photodiode?

The photodiode is a simple light detector and voltage-based operating device. It consists of various types of fibers and different lenses. It has a surface area that emits the light. When the surface area of a photodiode increases, the response time becomes slow. The photodiode has three major components including the P+ region, P-n junction, and N-type side. The P+ region is the positive electrode. This element is located on the top of the diode. The P-n junction is an omnidirectional layer between the P+ and N- region. The N-type or negative electrode is located at the bottom of the diode. It reflects the light. It is important to remember that photodiodes are light-sensitive devices which is linear and have low resistance.

Photodiode

Types of Photodiode

As per the construction method and different functions, there are four major types of diodes. Let us discuss this in detail.

PN Photodiode

It was the first developed photodiode which was not advanced. The depletion region of a diode is responsible for the photodetection process. These diodes are small and they do not have much sensitivity.

Schottky Photodiode

The Schottky Photodiode uses the Schottky diode which is a small diode junction but works at high speed. These photodiodes are used in optical communication where the bandwidth is high.

PIN Photodiode

The PIN diode is the most common type of photodiode that can gather more photons from light sources. This diode has a wide intrinsic area between the P and N region which collects more light and offers a low capacitance.

Avalanche Photodiode

This type of diode can be used in the low light areas. These lights have high gain levels and they generate high levels of noise. This type of photodiode applies to all devices.

Working of Photodiode

The photodiode is a light detector which converts the light source to electric energy. It is a voltage-based operating device. The photons hv are the energy packets of the light. Here is the working process of the photodiode as mentioned below.

• The photodiode absorbs the light energy as the photon hv.
• When the energy of the photon hv is higher than the energy gap, the photodiode creates new electron-hole pairs.
• The new electron-hole pairs are always generated in the depletion zone of this diode.
• The newly sorted electrons are transferred to the n side and holes travel to the p side. This movement creates the condition to produce EMF and current flow.
• When the amount of photocurrent becomes equal to the light intensity, it creates a condition of reverse bias.

Advantages and Disadvantages of Photodiode

Here are the different advantages and disadvantages of photodiode as mentioned below.

Advantages of Photodiode

Here are some advantages of the photodiode as mentioned below.

• Photodiodes are less resistant. They are quick and have a high speed to operate.
• These photodiodes have a long lifespan and are considered the fastest photodetector.
• The spectral response of the photodiode is good and does not need high voltage to operate.
• The photodiode has a high quantum efficiency with less noise.

Disadvantages of Photodiode

Here are some disadvantages of the photodiode as mentioned below.

• The temperature stability of the photodiode is poor and their active area is too small.
• A usual photodiode with the PN junction always has a high response time with less sensitivity.

Applications of Photodiode

Let us discuss the different types applications of the photodiodes as mentioned below.

• The photodiode can be used as the photodetector.
• These photodetectors works like as the photoconductors.
• In the different photomultiplier tubes we can find the photodiodes.
• Photodiodes are used in consumer electronics devices.
• The photodiodes are the major component of the clock radios, cameras, and street lights. Here photodiodes work as the photoconductors.
• In science and industries, photodiodes are used for measurement purposes which have enhanced and more linear responses.

Conclusion

Photodiodes helps to achieve fast data transmission through fiber optic systems. They are important components in many technologies because they convert light into electrical signals. Photodiodes founds its use in medical device for accurate monitoring and diagnostics. Photodiodes founds its use in electronics like remote controls and barcode scanners. Photodiodes efficiency, reliability, and small size make them versatile and essential, driving innovation in various fields.

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Frequently Asked Questions on Applications of Photodiode-FAQ’S

What is the main application of photodiode?

The photodiode is the p-n junction device. It is also considered as the photo-detector. It is a voltage-based operating device. The photons hv are the energy packets of the light.

What is the application of photodetectors?

Photodiodes are used in different electronics devices. The best examples are smoke detectors, televisions, or remotes. The photodiodes are the major component of the clock radios, cameras, and street lights. Here photodiodes work as the photoconductors.