APD Photodetector Modules

High-sensitivity avalanche photodetector modules with integrated transimpedance amplification and temperature compensation — fiber-coupled and free-space options from 400–1700 nm for DTS Raman receivers, distributed fiber sensing, LiDAR, UV fluorescence and laboratory weak-light detection.

Need help choosing? View selection guide ↓

  • 400–1700 nm Si & InGaAs material options
  • 10 MHz – 1 GHz Bandwidth models for sensing & comms
  • nW-level sensitivity Built-in TIA + APD gain
  • FC/APC or free-space Fiber sensing & benchtop setups

APD Products by Application

Fiber-Coupled APD for DTS & Sensing

FC/APC input modules for distributed fiber optic systems — dual-channel DTS-APD for Raman Stokes/anti-Stokes detection, and the versatile APD20 series for DVS/DAS receive paths and general nW-level fiber-coupled measurement.

Free-Space APD Modules (Si / InGaAs)

General-purpose free-space avalanche photodetectors with 10–400 MHz bandwidth — Si (400–1100 nm) and InGaAs (1000–1700 nm) versions for LiDAR, weak-signal lab work and optical cage integration. Temperature-compensated T-series variants available.

UV-Enhanced & Visible APD

Large-area silicon APDs with UV-enhanced response for fluorescence, chemical analysis and low-light visible/near-UV experiments — 3 mm photosensitive diameter, temperature compensation.

1064 nm APD for LiDAR & Aerosol Detection

Silicon APD modules optimized for 1064 nm — high gain for atmospheric aerosol radar, LiDAR and Yb-band free-space detection. Standard and temperature-compensated (T) models.

High-Speed & Position-Sensing Detectors

GHz-class free-space APD for space optical communication experiments, plus four-quadrant photodetectors for beam tracking, alignment and AOM/laser stabilization.

How to Choose an APD Module

  • Building a Raman DTS receive path? DTS-APD dual-port InGaAs module (1000–1700 nm, up to ~150 MHz) — pair with NSFL-30 pulsed laser and DTS modules; see DTS Applications.
  • Fiber-coupled weak-light detection (DVS/DAS/lab)? APD20 — choose Si (APD20A, 400–1000 nm, MM fiber) or InGaAs (APD20C, 1000–1700 nm, SM fiber); bandwidth from 10 MHz to 1 GHz depending on model suffix.
  • Free-space bench setup (LiDAR, cage system)? APD430 (Si or InGaAs, 10–400 MHz) or APD430T when stable gain vs temperature is critical.
  • UV / fluorescence at 355 nm region? APD12703 (300–1100 nm) or APD12702 (300–1000 nm) with 3 mm active area.
  • 1064 nm LiDAR or aerosol radar? APD1064 or temperature-compensated APD1064T.
  • Need balanced or PIN detection instead? See Balanced Photodetectors for interferometric DVS/DAS, or PIN Amplified Photodetectors when avalanche gain is not required.

What Are APD Photodetector Modules?

An avalanche photodiode (APD) provides internal gain via impact ionization, making it far more sensitive than a standard PIN photodiode for weak optical signals. YB Photonics APD modules integrate the photodiode, high-voltage bias, transimpedance amplifier (TIA) and often M-factor temperature compensation in a compact enclosure — outputting a voltage on SMA for oscilloscopes, DAQ cards or demodulation hardware.

Applications span DTS Raman reception (DTS-APD), fiber sensing receive paths (APD20), LiDAR and aerosol detection (APD1064 series), and general laboratory weak-light measurement (APD430/1270 series). Pair with our DTS systems, DAS modules and DAQ cards for complete sensing chains.

Key Specifications to Compare

Parameter Why it matters Typical range in this category
Wavelength Must match laser/signal band 400–1000 nm (Si); 1000–1700 nm (InGaAs); 1064 nm enhanced
Coupling Fiber system vs free-space optics FC/APC fiber (APD20, DTS-APD); free-space (APD430, APD1270)
Bandwidth Temporal resolution & DAQ match 10 MHz – 1 GHz (model dependent)
NEP / sensitivity Weakest detectable optical power Sub-pW/√Hz class on high-gain models
Temperature compensation Stable gain over ambient range M-factor TC on APD20/DTS-APD; T-series (430T, 1064T)
Output Interface to acquisition 50 Ω SMA, DC-coupled, 9–12 V supply typical

Frequently Asked Questions

APD vs PIN photodetector — when do I need an APD?
Choose APD when signals are very weak (nW or below) and internal avalanche gain improves SNR — typical for DTS Raman returns, long-range LiDAR and sensitive lab detection. PIN modules (PD series) suit stronger signals or when lower noise without avalanche multiplication is preferred.
APD20 vs APD430 — what is the difference?
APD20 is fiber-coupled (FC/APC) for fiber sensing and communication links. APD430 is free-space input for optical bench, cage systems and LiDAR — similar bandwidth tiers but different mechanical interface.
Which APD for DTS Raman detection?
DTS-APD is purpose-built: dual-channel, InGaAs, 1000–1700 nm, FC/APC — designed alongside DTS pulsed lasers and DAQ in Raman temperature systems. General APD20C can also work in custom DTS builds.
Do modules include cables and power supply?
YB Photonics typically ships APD modules with SMA–BNC RF cable and power adapter — confirm accessories when ordering. Most standard models are in stock for fast delivery.