Thorlabs APD-430A Silicon Avalanche Photodetector 400-1000nm

The Thorlabs APD430A is a Si Variable-Gain Avalanche Detector module designed for free-space detection of light in the 400 to 1000 nm wavelength range. It features a bandwidth of DC to 400 MHz, a temperature-compensated design, internal gain (M factor), and internal SM05 and external SM1 threading for easy integration with other optical components. 

Key Specifications & Features 

• Type: Silicon (Si) Avalanche Photodetector (APD)
• Wavelength Range: 400 - 1000 nm
• Bandwidth: DC - 400 MHz
• Gain: Variable gain (M factor)
• Temperature Compensation: Yes
• Optical Input: Free-space with internal SM05 and external SM1 threading
• Taps: 8-32 taps for mechanical mounting

What is an Avalanche Photodetector?

An APD is a photodetector that uses internal gain to increase its sensitivity. 

• When a photon strikes the detector, it creates an electron-hole pair.
• The strong electric field present in the APD accelerates these charge carriers.
• These accelerated carriers then create secondary electrons through impact ionization, leading to an "avalanche" of charge carriers.
• This process results in a significant increase in the detected signal, which is quantified by the multiplication factor, M.

Why Choose the APD430A?

This detector is ideal for applications requiring high sensitivity and low optical power detection in the visible and near-infrared spectrum, such as LIDAR. The variable gain and temperature compensation offer increased control and stability over varying ambient conditions.