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Photobiological Safety of luminaires and Light Sources
Štěpánek, Jaroslav ; Bendová,, Zdeňka (referee) ; Vik,, Michal (referee) ; Škoda, Jan (advisor)
This doctoral thesis called “Photobiological safety of luminaires and light sources” has focused on an optical radiation and its relation to human body. The thesis describes possible consequences on living tissue during excessive exposure to optical radiation. Among others the work deals with the light source, lamp and optical devices evaluation in dependence of photobiological safety. There is created a method of light source evaluation procedure for photobiological safety in accordance with ČSN EN 62471. The meaning of this procedure is based on its hazard calculation from measured values of irradiation to different photometric distances. Validity of procedure is verified by light source measuring, in which visual angle and photometric distance have been changed. There we can also find an application of this procedure in the UV source evaluation, which helps to determine a safe distance away from UV sources not to create any danger. The evaluated UV sources include a UVA luminaire with a dominant wavelength of 365 nm or an arc of an electric welder. The thesis also describes a method of evaluating light sources for blue light hazard for an aphakic and pseudophakic eye. This method can also help to determine the hazard for the eye without lens or with some implanted lens. Furthermore, there was developed the method of the blue light hazard assessment depending on the age of an exposed person. In terms of the work there was also created a computer programme evaluating photobiological safety resulting from the spectral data having been stored in the library programme or from spectroradiometric measurement data. The work also marginally deals with the topic of circadian rhythms, which are closely related to photobiological manifestation in an human body. Above all the work compares light sources for which equivalent illuminances are calculated, consequently light sources have the same effect on suppressing the melatonin hormone production.
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Photobiological Safety of luminaires and Light Sources
Štěpánek, Jaroslav ; Bendová,, Zdeňka (referee) ; Vik,, Michal (referee) ; Škoda, Jan (advisor)
This doctoral thesis called “Photobiological safety of luminaires and light sources” has focused on an optical radiation and its relation to human body. The thesis describes possible consequences on living tissue during excessive exposure to optical radiation. Among others the work deals with the light source, lamp and optical devices evaluation in dependence of photobiological safety. There is created a method of light source evaluation procedure for photobiological safety in accordance with ČSN EN 62471. The meaning of this procedure is based on its hazard calculation from measured values of irradiation to different photometric distances. Validity of procedure is verified by light source measuring, in which visual angle and photometric distance have been changed. There we can also find an application of this procedure in the UV source evaluation, which helps to determine a safe distance away from UV sources not to create any danger. The evaluated UV sources include a UVA luminaire with a dominant wavelength of 365 nm or an arc of an electric welder. The thesis also describes a method of evaluating light sources for blue light hazard for an aphakic and pseudophakic eye. This method can also help to determine the hazard for the eye without lens or with some implanted lens. Furthermore, there was developed the method of the blue light hazard assessment depending on the age of an exposed person. In terms of the work there was also created a computer programme evaluating photobiological safety resulting from the spectral data having been stored in the library programme or from spectroradiometric measurement data. The work also marginally deals with the topic of circadian rhythms, which are closely related to photobiological manifestation in an human body. Above all the work compares light sources for which equivalent illuminances are calculated, consequently light sources have the same effect on suppressing the melatonin hormone production.
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