PM Tap Photo Detector Polarization Maintaining Tap PD 1260nm 1620nm Optical Power Monitor

  The PM Tap Photo Detector is a monitoring device that integrates a polarization-maintaining fiber tap and a photodetector into a single package. It enables real-time detection and feedback of optical power without interrupting the main optical path. The product operates over a wide wavelength range of 1260–1620 nm and supports multiple tap ratios of 1:99, 3:97, and 5:95, covering O/C/L bands and 1310/1550 combination systems. It features low typical insertion loss (0.35–0.5 dB) and return loss exceeding 45 dB. Combined with its polarization-maintaining fiber design, it is particularly suitable for online monitoring scenarios in polarization-maintaining or polarization-sensitive systems such as DWDM, ROADM, and amplifiers.

  The insertion loss at the tap end (excluding connector) is only approximately 0.35 / 0.4 / 0.5 dB (corresponding to 1:99 / 3:97 / 5:95), resulting in minimal power attenuation of the main service channel and helping to maintain system OSNR and power margin.

  The built-in PD provides a responsivity of 8～12 / 23～38 / 40～60 mA/W at different tap ratios, enabling stable detection at low optical power, making it suitable as a front-end device for power monitoring, gain control, and alarm triggering.

  Dark current is less than 0.5 nA (25℃) / 2 nA (70℃). Combined with a -5 V bias and ≤20 V reverse withstand voltage design, this results in low noise and a wide dynamic range for the detection circuit, suitable for long-term operation in environments ranging from room temperature to higher temperatures.

  Utilizing Corning PM1310 Panda polarization-maintaining fiber, the extinction ratio at 23℃ is ≥18 dB, and the wavelength-dependent loss (WDL) is ≤0.3 dB. This ensures polarization maintenance while maintaining minimal loss variation across the entire wavelength range, making it suitable for polarization-sensitive networks and testing systems.

  The device is packaged in a small steel tube. The input is polarization-maintaining fiber, and the output has two electrode pins (clearly marked positive and negative), facilitating direct soldering to amplifier or monitoring boards. The standard connector is FC/APC, enabling quick integration and maintenance with existing fiber optic links.

  Standard support includes three tap ratios: 1/99, 3/97, and 5/95. Customization is available based on O/C/L bands or 1310 & 1550 nm combined wavelengths. Pigtail type (250 μm, 0.9 mm, 2.0 mm, 3.0 mm), length, and COM/Port connector type can be flexibly selected via order codes, facilitating unified platform design for different equipment manufacturers and system integrators.

  Based on the dimensions shown on page 2 of the datasheet, the device body is a φ5.5 mm steel tube structure. The central body length is approximately 18.36 mm, and the total length of the fiber optic and electrode sections at both ends is approximately 40 mm. The overall structure is compact, suitable for installation in limited spaces within modules or chassis.

• Fiber Type: Corning PM1310 Panda Fiber, slow-axis operation, fast-axis blocked;
• Pigtail Sheath: Optional 250 μm bare fiber, 0.9 mm tube, 2.0 mm, 3.0 mm fiber optic cable, etc.;
• Standard Length: 1.0 m (Code 10, customizable);
• Standard Connector: FC/APC, others such as FC/UPC, SC/UPC, SC/APC, LC/UPC, LC/APC can be configured  according to order information.

• PD Bias Voltage: -5 V;
• Reverse Voltage: ≤20 V;
• Pin orientation is clearly marked Positive / Negative in the end view for easy PCB design and soldering.

• Operating Temperature: -5～+65 ℃;
• Storage Temperature: -40～+85 ℃;
• Note: The version with connectors increases insertion loss by approximately 0.3 dB and reduces return loss by  approximately 5 dB. Appropriate margins should be allowed when designing link budgets.

• DWDM channel monitoring
• Optical line protection monitoring
• ROADM multiplexers
• Gain monitoring in amplifier