Enabling Precision Dosimetry in PDT and Phototherapy — PTCal150

Accurate dosimetry is essential to ensure effective and safe phototherapy and photodynamic therapy (PDT) treatment. The PTCal150 sets the benchmark for accurate measurement of spectral irradiance of all PDT and phototherapy light sources in hospitals as well as in clinical research.

The PTCal150 spectroradiometer has been designed with research-grade optical components, thus enabling highly accurate patient exposure data and offering total confidence in phototherapy radiometer calibration.

The device enables determining warm-up characteristics and gaining insights into irradiance temporal variation to guide the application of PDT and phototherapy.

Superior stray light performance is ensured over a very wide dynamic range by the compact double monochromator that includes the precision cosine-corrected input optic, thereby enabling precise measurement of LED, tungsten filament, xenon arc, metal halide, dichroic, and fluorescent light sources alongside full-spectrum lamps.

Core Advantages

  • Choice of UV/UV-vis configurations customized to the phototherapy facilities of customers
  • High-accuracy spectroradiometry can be performed within a few steps
  • Completely automated measurement process through USB interface
  • Alignment-free calibration standards enable satisfying national metrology standards


  • Excellent dynamic range offered by integrated PMT high voltage supply and dual-channel, six-decade picoammeter
  • Windows control software (BenWin+) offers complete automation through USB 2.0
  • Double monochromator-based spectroradiometer including precision transmission cosine diffuser
  • Placed in a single, sturdy housing, enabling the device to be easily carried between clinics and laboratories
  • Flexible fibre bundle equipped with optional end- or side-view entrance optic for convenient coupling of light from the transmission diffuser to the monochromator

Reported Parameters

  • Erythemal irradiance
  • Spectral irradiance