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Absolute calibration of optical power and fluence rate for PDT: Report of AAPM TG140



Marla L. Dowell, Timothy Zhu, Christopher Bonnerup, Valdir Colussi, Jarod Finlay, Lothar Lilge, Thomas Slowery, claudio sibata


This report is primarily concerned with methods for optical calibration of laser power and light fluence rate for continuous wave (CW) light sources, predominantly used in photodynamic therapy (PDT). Dosimetry of light is very important for PDT, however, no clear standard has been established for the calibration procedure nor the selection of power meters suitable for light power calibration. The purposes of the report are to provide guidance for establishing fundamental calibration procedure for thermopile power meter and establish calibration uncertainty for most commercially available power meter and head assembly. We have also provided a review of the use of various power meters for CW and pulsed optical sources and provided recommend frequency for optical power meter calibrations and guidance for routine QA procedure.
Medical Physics


optical power, photodynamic therapy


Dowell, M. , Zhu, T. , Bonnerup, C. , Colussi, V. , Finlay, J. , Lilge, L. , Slowery, T. and sibata, C. (2013), Absolute calibration of optical power and fluence rate for PDT: Report of AAPM TG140, Medical Physics, [online], (Accessed June 16, 2024)


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Created July 23, 2013, Updated November 10, 2018