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Macam have listed below a number of publications relating to light measurement applications. Some of these are from a particular field in science or medicine but should also be of general interest.

Full details can be obtained from the Authors or the publishers.

Internet sites discussing light measurement applications or publishing related data have also been listed.



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1. A study of the directional response of ultraviolet radiometers: I. Practical evaluation and implications for ultraviolet measurement standards.

2. A study of the directional response of ultraviolet radiometers: II. Implications for ultraviolet phototherapy derived from computer simulations.

3. Penetration of solar UVB radiation in shallow tropical waters and its potential biological effects on coral reef; results from the central Indian Ocean and Andaman Sea.

4. Solar damage in intertidal corals.

5. Tissue retraction in the scleractinian coral Coeloseris mayeri, its effect upon coral pigmentation, and preliminary implications for heat balance.

6. Solar ultraviolet spectroradiometery in New Zealand: instrumentation and sample results from 1990.

7. Polysulphone film as an underwater dosimeter for solar ultraviolet-B radiation in tropical latitudes.

8. Tm3+-doped tellurite glass for a broadband amplifier at 1.47 µm.

9. Pr3+-doped fluoride glass for a 589 nm fibre laser



A study of the directional response of ultraviolet radiometers:
I. Practical evaluation and implications for ultraviolet measurement standards

S D Pye (1) and C J Martin (2) 2000
Physics in Medicine and Biology Vol 45 pp 2701-2712

(1) Department of Medical Physics and Medical Engineering, Western General Hospital, Edinburgh EH4 2XU

(2) Health Physics, Department of Clinical Physics and Bio-Engineering, North Glasgow University Hospitals NHS Trust, Western Infirmary, Dumbarton Road, Glasgow G11 6NT Scotland

Abstract. The directional responses of a range of ultraviolet radiometers commonly used for irradiance measurements of UVB and UVC have been studied. Radiometers with 24 diffuser/filter combinations were assessed using a deuterium source, and three different diffuser/filter designs were assessed using a monochromatic source. The directional responses of the radiometers have been calculated and expressed in terms of figures of merit similar to those described for (photopic) illuminance meters in BS 667 (1996) and CIE 69 (1987). Those radiometers that performed best for the measurement of both small and extended sources of UVB and UVC had raised PTFE diffusers. We conclude that UV radiometers with directional response error f2 < 10% are readily available commercially, and that it would be appropriate for future ultraviolet standards to set an upper limit of 5% on f2. This would ensure that the overall uncertainty in irradiance measurements of extended ultraviolet sources is not dominated by the error in the directional response of the radiometer.



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A study of the directional response of ultraviolet radiometers:
II. Implications for ultraviolet phototherapy derived from computer simulations

C J Martin (2) and S D Pye (1) 2000
Physics in Medicine and Biology Vol 45 pp 2713-2729

(1) Department of Medical Physics and Medical Engineering, Western General Hospital, Edinburgh EH4 2XU

(2) Health Physics, Department of Clinical Physics and Bio-Engineering, North Glasgow University Hospitals NHS Trust, Western Infirmary, Dumbarton Road, Glasgow G11 6NT Scotland

Abstract. A theoretical model has been used to simulate irradiances for ultraviolet (UV) phototherapy cabinets and other sources. The accuracy of the simulation results has been checked by comparison with experimental measurements. The simulations have been used to study the influence of different factors on UV phototherapy exposure and to develop recommendations for the operation and calibration of phototherapy cabinets. Many radiometers used in the evaluation of skin doses have input optics with directional responses that are not proportional to the cosine of the angle of incidence for the UV radiation. Data on radiometer directional responses have been incorporated into the simulations, which show that the poor directional responses for some radiometers currently in use will give errors of 20%-50% in the assessment of irradiance. The influence of lamp source geometries employed for radiometer calibration has been investigated. UV phototherapy dosimetry commonly uses a spectroradiometer and a radiometer in transfer of irradiance calibrations from a small standard UV lamp to a large area source with a different UV spectrum. Recommendations are given on the range of acceptability for radiometer directional responses and a method is described for determining whether these are fulfilled. Recommendations are made on the techniques that should be used for calibration.



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Penetration of solar UVB radiation in shallow tropical waters and its potential biological effects on coral reef; results from the central Indian Ocean and Andaman Sea.
Richard P. Dunne, Barbara E. Brown
Department of Marine Science and Costal Management, University of Newcastle, Newcastle upon Tyne NE1 7RU, United Kingdom
Marine Ecology Progress Series Vol. 144: pp 109-118, 1996

Abstract: This paper presents the first complete data of global downwelling irradiance (Ed) and the diffuse attenuation coefficient (Kd) for solar ultraviolet-B (UVB; 280 to 320 nm) in tropical waters. The penetration of solar UVB into shallow (0 to 5 m) seawater at 3 sites in the central Indian Ocean and Andaman Sea, adjacent to areas of coral reefs, was studied using a semi-submersible scanning spectroradiometer. Downwelling global spectral irradiance (Ed) was measured at 2 nm intervals over the wavebands 280-320 nm (UVB), 320-400 nm (UVA) and 400-700 nm (PAR) above the sea surface (0+ m) and at each of 5 depths (1, 2, 3, 4, and 5 m). The three sites consisted of an ocean atoll in the Maldives (central Indian Ocean), a small (8 km²) high island 11 km off the continental coastline at Phuket, Thailand (Andaman Sea), and an inshore reef at Phuket. Ed at each of the depths was integrated over the waveband as a percentage of the above-water irradiance. Ed (UVB) at 5 m depth was found to decrease to 12% of the incident irradiance at the mid ocean atoll, to 2% for the high island site, and to 0.4% in the turbid waters of the inshore reef. A 1% Ed(UVB) depth was computed for each site and found to be 11, 6 and 3 m respectively. The diffuse attenuation for downwelling irradiance (Kd) for the depth range 0- m (just below the surface) to 5 m showed a very rapid attenuation with decreasing wavelength in the UVB at all sites. Biological damage potential, as weighted by the DNA-damage action spectrum, showed a more rapid attenuation with depth than Ed(UVB), with a 1% EDNA depth of 9 m for the ocean atoll, 4.7 m for the costal island, and 2.6 m for the inshore reef.



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Solar damage in intertidal corals.
B. E. Brown, Richard P. Dunne, T.P. Scoffin (2), M.D.A. Le Tissier
1. Department of Marine Science and Costal Management, University of Newcastle, Newcastle upon Tyne NE1 7RU, United Kingdom
2. Department of Geography and Geophysics, University of Edinburgh, Edinburgh, EH9 3JW, United Kingdom
Marine Ecology Progress Series Vol. 105: pp 219-230, 1994

Abstract: Solar irradiation has been cited as a possible cause of bleaching in corals, either acting alone or in conjunction with other environmental factors. However, evidence of a solar involvement in naturally occurring bleaching is still largely conjectural. We have recorded a particular type of naturally occurring bleaching damage at intertidal sites at Phuket, Thailand for a number of years which has a string directional component. Use of tidal data, sun track analysis, and solar irradiance measurements have enabled us to show that this bleaching directly corresponds to sun altitude and azimuth. Our work has shown that for the massive coral Goniastrea aspera, bleaching is induced during periods of subaerial exposure with high sun altitude and irradiance. Furthermore, on-site measurements of solar irradiance mitigate against the biologically damaging effect of shorter wavelength ultraviolet radiation (UVR), as a major causative factor. Dessication, heating, or photochemical reactions by photosynthetically active radiation (PAR) (400-700nm) remain possible candidates for further investigation.



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Tissue retraction in the scleractinian coral Coeloseris mayeri, its effect upon coral pigmentation, and preliminary implications for heat balance.
B. E. Brown, M.D.A. Le Tissier, Richard P. Dunne
Department of Marine Science and Costal Management, University of Newcastle, Newcastle upon Tyne NE1 7RU, United Kingdom
Marine Ecology Progress Series Vol. 105: pp 219-230, 1994

Abstract: Extreme tissue retraction in the agariciid coral Coeloseris mayeri occurs during periods of sub-aerial exposure. The retraction response appears to involve independent movement of oral and aboral tissue layers to such an extent that skeletal septa are uncovered. Tissue retraction results in a significant paling in colony colour which does not involve any reduction in either zooxanthellae abundance or chlorophyll concentration. Adaptive benefits of the response include increased albedo, leading to a reduction in absorbed solar energy of 10% for wavelengths between 280 and 700nm, and possible avoidance of photochemical damage or photoinhibition at high solar irradiance. the degree of retraction is governed by environmental conditions, including length of sub-aerial exposure, and intensity of solar irradiance.



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Solar ultraviolet spectroradiometry in New Zealand: instrumentation and sample results from 1990.
R. L. McKenzie, P. V. Johnston, M. Kotkamp, A. Bittar, and J. D. Hamlin
Applied Optics Vol. 31 No.30: pp 6501-6509

Abstract: In 1988 the New Zealand Department of Scientific and Industrial research initiated a program to characterize the spectrum of solar ultraviolet radiation reaching the ground in New Zealand and to identify the extent and causes of its variability. Routine measurements began at Lauder (45°S, 170°E) in December 1989. The instrumentation, measurement strategy, and calibration procedures are discussed and uncertainties in the measurements are analyzed. With the present system useful measurements at 1-nm resolution are limited to irradiances greater than 10E-3 µW.cm-2.nm-1, which corresponds to a lower limit in wavelength in the region 290-295 nm (depending on the Sun angle and ozone amount). This is a useful lower limit for many applications of relevance to the biosphere. Results from the first year of operation are presented and discussed.



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Polysulphone film as an underwater dosimeter for solar ultraviolet-B radiation in tropical latitudes.
Dunne,RP (1999)
Marine Ecology-Progress Series Vol. 189, pp 53-63.

Abstract: This paper examines the potential of polysulphone film (PSF) as a dosimeter for unweighted solar ultraviolet-B radiation (UVB; 280 to 320 nm) in different seawater conditions in tropical latitudes. PSF's accuracy is determined by water type and depth range. The film may be used over a depth range of 7 m with measurement errors of less than 5% in oceanic type waters, such as are found around coral atolls and islands. In clear but coloured continental coastal waters the range decreases to 2.2 m. Calibration functions are presented for use of the film both in air (e.g, an intertidal setting) and underwater over the UVB dose range of about 1.5 to 40 kJ m(-2). A comprehensive analysis of errors arising from the use of PSF, in air and underwater, is given. The film offers a cost-effective and simple technique for studying biological responses to solar UVB radiation in many tropical marine habitats, including intertidal and subtidal coral reefs.



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Tm3+-doped tellurite glass for a broadband amplifier at 1.47 µm
Mira Naftaly, Shaoxiong Shen and Animesh Jha
Department of Materials, University of Leeds, United Kingdom
APPLIED OPTICS / Vol. 39, No. 27 / 20 September 2000 / pp. 4979-4984

Abstract: Tm3+-doped tellurite glass is investigated as a host for a broadband amplifier at 1.47 µm. The Tm3+ fluorescence spectrum, lifetime and cross-section in tellurite glass are compared with those in fluorozirconate glasses. The advantages of a Tm3+-tellurite amplifier, especially when employed in combination with Er3+-tellurite 1.55 µm amplifier, are discussed.



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Pr3+-doped fluoride glass for a 589 nm fibre laser
Mira Naftaly, Caroline Batchelor, Animesh Jha
JOURNAL OF LUMINESCENCE / Vol. 91 / 2000 / pp. 133-138

Abstract: Fluoroaluminate glass was investigated for a Pr3+-doped fibre laser at 589 nm using the (3P1+3P0) ---> 3H6 transition. Enhanced emission at 589 nm was obtained by thermally populating the 3P1 level. Results indicate that lasing at 589 nm is possible in fluoroaluminate glass at elevated temperatures.



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