A photodetector array is basically a combination of tiny photosensors working together. These sensors identify light particles and transform them into an electrical current using p-n junctions, which are typical semiconductor interfaces. Photodetector arrays can track how light expands along a line or beam or even capture images based on light arrays. They generally come in two major types: photodiodes and phototransistors.
How Do Photodetector Arrays Operate?
Photodetector arrays operate based on the photoelectric effect process. They work by knocking electrons out of a material and producing electrical currents. Whenever light hits the array, it excites electrons and makes them move out of their usual energy level to a higher one. As electrons move, they create measurable electrical power. The stronger the intensity of light, the more electrons are excited, generating a more significant amount of current. The amount of the generated energy depends upon the intensity of light that is hitting the photodetector array. The more vivid the light, the more electrons will be excited, and a larger amount of current will be produced.
What are the Popular Photodetector Array Types?
Several types of photodetector arrays are available in the market, each created with its own benefits and features to meet different application needs. Some of the commonly used types are outlined below:
- Photodiodes: The most typical type of photodetector arrays. Photodiodes are made using high-grade semiconductor materials like silicon with a p-n junction. They are cost-effective and easy to use. A photodiode produces measurable electrical currents when hit by a direct light source.
- Phototransistors: This type of photodetector array is much more sensitive than photodiodes. They operate the same as photodiodes but have an extra transistor that magnifies the electrical current. They can be widely found in imagery and spectroscopy.
- Charge-coupled Devices CCDs: A type of photodetector array utilised to create images. They operate by storing the electrical energy produced by every pixel of the array.
- Active-pixel Sensors: Function exactly like CCDs but have an amplifier and a readout circuit installed in each pixel, making them more efficient and less noisy.
Versatile Uses of Photodetector Arrays
Augmented Reality: Used in augmented reality AR systems.
- Datacom, Broadband and CATV Network Testing: Applied to test or examine the performance of datacom, broadband and CATV networks. They are responsible for measuring optical signal strength and notify faults in a network.
- 3D Scanning: They are generally used to capture images of different objects from multiple angles.
- Facial Recognition Systems: Used in facial recognition systems to identify people by their facial characteristics.
- Monitoring Systems: Observes and monitors data centre equipment and active optical cable connections. They detect faults in a connection or equipment and also measure the temperature and power usage of the equipment.
Bottom Lines
Photodetector arrays are indispensable components for almost every electronic machine and system. They measure light intensity, create images, and detect objects. Photodetector arrays come in various types, each equipped with its own properties. Choosing the right type for your project completely depends on the particular needs of your application.
