Radiation Measurement in Photobiology

List of Contributors

Preface


1. Basic Principles of Light Measurement


1.1. Light and Radiation — Introduction


1.1.1. What do we Mean by “Light”?


1.1.2. The Measurement of Light


1.1.3. Radiation and Radiation Measurements


1.1.4. Photon Quantities


1.1.5. Other photobiological Measurements


1.1.6. The Spectral Power Distribution of Light Sources

References


2. Optical Radiation Detectors

Nomenclature


2.1. Introduction


2.2. Detector Performance Parameters


2.3. Thermal Detectors


2.3.1. Basics


2.3.2. The Thermopile


2.3.3. The Pyroelectric Detector


2.3.4. Other Thermal Detectors


2.4. Photon Detectors


2.4.1. Basics


2.4.2. Photoemissive Detectors: The Vacuum Phototube and the Photomultiplier


2.4.3. Junction Photodetectors


2.4.4. Photoconductors


2.5. Photodetector Formats


2.6. Example Applications

References


3. Calibration of Light Sources and Detectors


3.1. Calibration of Light Sources


3.1.1. Luminous Intensity and Illuminance


3.1.2. Luminous Flux


3.1.3. Luminance


3.1.4. Low-Level Photometry


3.1.5. Spectroradiometry


3.1.6. Correlated Colour Temperature


3.2. Calibration of Detectors


3.2.1. Relative Spectral Responsitivity


3.2.2. Absolute Responsivity


3.2.3. Responsivity of Thermopiles for Total Radiation

References


4. Techniques for Spectroradiometry and Broadband Radiometry


4.1. Comparison of Radiometric and Photometric Units with Biologically Effective Quantities


4.2. Spectroradiometers


4.2.1. Functional Components


4.2.2. Calibration of Spectroradiometers


4.2.3. Sources of Error in Spectroradiometry


4.3. Broadband Radiometers


4.3.1. Functional Components


4.3.2. Physical Performance


4.3.3. Calibration

References


5. Action Spectroscopy


5.1. Introduction


5.2. Monochromatic Sources


5.3. Detector Types


5.3.1. Thermoelectric Detectors


5.3.2. Photoelectric Detectors


5.4. Linearity


5.5 Measuring Low Radiation Levels


5.6. Receiver Geometry


5.6.1. Normal Incidence Detectors


5.6.2. Cosine-Corrected Receivers


5.6.3. Spherical Response Receivers


5.6.4. Receiver Calibration


5.7. Error

References


6. Applications of Lasers in Photobiology and Photochemistry


6.1. Introduction


6.2. Time-Resolved Studies


6.2.1. Fluorescence


6.2.2. Pump and Probe Experiments


6.3. Spectroscopic Studies


6.4. Lasers and Living Biological Systems


6.5. Conclusions

Acknowledgements

References


7. Ultraviolet Radiation Dosimetry with Polysulphone Film


7.1. Preparation of Polysulphone Film


7.2. Optical Properties of Polysulphone Film


7.3. Calibration of Polysulphone Film


7.3.1. Calibration by Spectroradiometry


7.3.2. Calibration by Broadband Radiometry


7.4. Errors Associated with Polysulphone Film Dosimetry


7.4.1. Within-Batch Variation


7.4.2. Dark Reaction and Effect of Temperature


7.4.3. Effect of Surface Contamination


7.4.4. The Uncertainty in the Measured Dose


7.4.5. Increasing the Reliability of Dose Measurements


7.4.6. The Problem of Spectral Sensitivity


7.5. Applications of Polysulphone Film Dosimetry


7.5.1. Personal Exposure to Natural Ultraviolet Radiation


7.5.2. Occupational Exposure to Artificial UVR


7.5.3. Ambient Solar UVR Monitoring


7.5.4. Monitoring Photochemical Processes

References


8. Computer Programs for Estimating Ultraviolet Radiation in Daylight


8.1. Introduction


8.2. Extraterrestrial Solar Irradiance


8.3. Sun—Earth Distance


8.4. Solar Elevation


8.5. Effect of Cloudless Atmosphere


8.6. Estimation of the Amount of Ozone and Absorption by Ozone


8.7. Other Effects of a Cloudless Atmosphere


8.8. Reflection from the Ground or Water Surface


8.9. Cloud Effects


8.10 Direction of Reference Plane


8.11. Biological Action Spectra


8.11.1. Generalized Medical Effects Spectrum


8.11.2. Erythema


8.11.3. Generalized Plant Damage Action Spectrum and DNA Spectrum


8.11.4. Photosynthesis


8.12. Direct Approaches


8.13. Comparison Between Models


8.14. Activity and Orientation of Organisms

Acknowledgements

References

Appendix


9. Optical Radiation Interaction with Living Tissue


9.1. Introduction


9.2. Basic Light—Matter Interactions


9.2.1. Surface Reflection


9.2.2. Absorption


9.2.3. Scattering


9.3. Measurable Quantities


9.4. Models for Photon Fluxes in Tissue


9.4.1. Kubelka—Munk Theory and Simple Extensions


9.4.2. Three- and Four-Flux Models


9.5. The Radiative Transfer Equation and its Relation to Two- and Four-Flux Models


9.6. More Effects to Consider


9.6.1. Optical Pathlength Increase


9.6.2. Sieve Effect


9.6.3. Fluorescence


9.6.4. Particular Surfaces of Natural Tissue


9.7. Light Gradients and Action Spectroscopy

References

Index