Thorlabs PM130D Silicon Photodiode Laser Power Meter

Overview

The Thorlabs PM130D is a high-sensitivity, benchtop silicon photodiode-based laser power meter engineered for precise, low-power optical measurements in research laboratories, photonics R&D, and quality assurance environments. It operates on the principle of photovoltaic conversion, where incident photons generate a proportional photocurrent in the calibrated Si sensor, which is then amplified and digitized with high linearity and low noise. Designed for continuous-wave (CW) and quasi-CW laser sources, the PM130D delivers stable, repeatable readings across its full dynamic range without requiring active cooling or zero-point drift compensation during typical operation. Its compact form factor and integrated digital display support rapid setup and real-time monitoring—ideal for alignment verification, cavity loss characterization, and low-power diode laser output validation.

Key Features

• Ultra-low detection threshold of 500 pW with 100 pW resolution—optimized for visible to near-infrared (VIS-NIR) lasers including 405 nm, 532 nm, 635 nm, 780 nm, and 1064 nm sources
• Calibrated silicon photodiode sensor with spectral responsivity traceable to NIST standards; optional factory calibration certificate available per ISO/IEC 17025 requirements
• Auto-ranging digital display with backlight, intuitive button interface, and unit toggle (W, mW, µW, nW, pW)
• Internal analog-to-digital converter with 16-bit resolution and <0.5% linearity error over full scale
• USB 2.0 interface (via optional PM100D-compatible interface module) supporting data streaming at up to 1 kHz sampling rate for time-resolved power profiling
• Rugged aluminum housing with thermal mass design to minimize ambient temperature-induced drift (<0.05%/°C typical)

Sample Compatibility & Compliance

The PM130D is compatible with free-space and fiber-coupled laser beams (with appropriate adapters), provided beam diameter remains within the active sensor area (Ø9.5 mm). It supports Gaussian, top-hat, and multimode spatial profiles with minimal dependence on beam uniformity due to its large-area, uniformly responsive photodiode surface. The instrument meets CE marking requirements for electromagnetic compatibility (EMC Directive 2014/30/EU) and low-voltage safety (LVD Directive 2014/35/EU). While not inherently GLP/GMP-certified, it supports audit-ready workflows when paired with Thorlabs’ PM100D-compatible software and optional 21 CFR Part 11-compliant logging modules—enabling electronic signatures, user access control, and immutable measurement records for regulated QC labs.

Software & Data Management

The PM130D is fully supported by Thorlabs’ free PM100D-compatible software suite (Windows/macOS), enabling real-time plotting, statistical analysis (min/max/avg/std dev), data export to CSV or MATLAB formats, and batch calibration file management. Firmware updates preserve sensor-specific correction coefficients stored in non-volatile memory. For integration into automated test benches, the device supports SCPI command set over USB or RS-232 (with adapter), allowing seamless scripting in Python, LabVIEW, or MATLAB. All raw measurement data include timestamp, wavelength setting, range selection, and sensor serial ID—ensuring full traceability in accordance with ISO 17025 clause 7.7.

Applications

• Characterization of low-power semiconductor lasers, VCSELs, and superluminescent diodes (SLDs)
• Optical attenuation verification in fiber optic component testing (isolators, circulators, couplers)
• Photodetector responsivity calibration using known reference sources
• Stability monitoring of ultra-stable oscillators and frequency-doubled systems
• Educational optics labs requiring quantitative irradiance and beam power correlation
• Pre-alignment diagnostics prior to M² or beam profiler measurements using BeamOn systems

FAQ

What is the maximum permissible beam power density for the PM130D sensor?

The silicon photodiode sensor is rated for ≤10 mW/cm² to prevent thermal saturation and long-term responsivity shift.
Can the PM130D measure pulsed lasers?

It is designed for CW and quasi-CW sources only; for nanosecond or femtosecond pulses, use energy meters such as Thorlabs’ PM101 or PM200 series.
Is NIST-traceable calibration included with purchase?

Standard units ship with factory calibration; NIST-traceable certificates with uncertainty budgets are available as an optional add-on (CAL-PM130D).
How often should recalibration be performed?

Annual recalibration is recommended for ISO/IEC 17025 compliance; more frequent intervals may apply in high-use or critical-accuracy environments.
Does the PM130D support analog voltage output?

No—this model features digital-only readout. For analog output capability, consider the PM120VA or PM204 variants.