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Berman, S. (2019). Opinion: Whither V(λ)? Lighting Research & Technology, 51(1), 4.
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Bijveld, M. M. C., van Genderen, M. M., Hoeben, F. P., Katzin, A. A., van Nispen, R. M. A., Riemslag, F. C. C., et al. (2013). Assessment of night vision problems in patients with congenital stationary night blindness. PLoS One, 8(5), e62927.
Abstract: Congenital Stationary Night Blindness (CSNB) is a retinal disorder caused by a signal transmission defect between photoreceptors and bipolar cells. CSNB can be subdivided in CSNB2 (rod signal transmission reduced) and CSNB1 (rod signal transmission absent). The present study is the first in which night vision problems are assessed in CSNB patients in a systematic way, with the purpose of improving rehabilitation for these patients. We assessed the night vision problems of 13 CSNB2 patients and 9 CSNB1 patients by means of a questionnaire on low luminance situations. We furthermore investigated their dark adapted visual functions by the Goldmann Weekers dark adaptation curve, a dark adapted static visual field, and a two-dimensional version of the “Light Lab”. In the latter test, a digital image of a living room with objects was projected on a screen. While increasing the luminance of the image, we asked the patients to report on detection and recognition of objects. The questionnaire showed that the CSNB2 patients hardly experienced any night vision problems, while all CSNB1 patients experienced some problems although they generally did not describe them as severe. The three scotopic tests showed minimally to moderately decreased dark adapted visual functions in the CSNB2 patients, with differences between patients. In contrast, the dark adapted visual functions of the CSNB1 patients were more severely affected, but showed almost no differences between patients. The results from the “2D Light Lab” showed that all CSNB1 patients were blind at low intensities (equal to starlight), but quickly regained vision at higher intensities (full moonlight). Just above their dark adapted thresholds both CSNB1 and CSNB2 patients had normal visual fields. From the results we conclude that night vision problems in CSNB, in contrast to what the name suggests, are not conspicuous and generally not disabling.
Keywords: Vision; Adolescent; Adult; Case-Control Studies; Child; *Dark Adaptation; Electroretinography; Eye Diseases, Hereditary/*physiopathology; Female; Genetic Diseases, X-Linked/*physiopathology; Humans; Light; Male; Middle Aged; Myopia/*physiopathology; Night Blindness/*physiopathology; *Night Vision; *Pattern Recognition, Visual; Surveys and Questionnaires; *Visual Acuity; Visual Fields
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Bortle, J. E. (2001). Introducing the Bortle Dark-Sky Scale. Sky Telesc, (60), 126–129.
Abstract: How dark is your sky? The relationship between light pollution and astronomy is a concern amateurs and professional astronomers alike. Are your skies dark enough? A precise answer to this question is useful for comparing observing sites and, more important, for determining whether a site is dark enough to let you push your eyes, telescope, or camera to their theoretical limits. Likewise, you need accurate criteria for judging sky conditions when documenting unusual or borderline observations, such as an extremely long comet tail, a faint aurora, or subtle features in galaxies.
Keywords: Vision; skyglow; visibility; sky brightness
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Boyce, P. R. (2018). The Present and Future of Lighting Research. SDAR* Journal of Sustainable Design & Applied Research, 6(1).
Abstract: The aim of this paper is to consider where lighting research is today and what its future might be. There is little doubt that, today, lighting research is an active field. A brief review of the topics being studied reveals that they range from residual studies on visibility and visual discomfort, through attempts to identify the influence of lighting on factors beyond visibility such as mood and behaviour, to the whole new field of light and health. But activity alone is not enough to justify a future. For lighting research to have a future it is necessary for it to
be influential. To become influential, research needs to focus its attention on outcomes that matter to people and the elements of those outcomes on which lighting is known to have a major influence. Further, researchers will have to be determined to overcome the barriers to changing lighting practice. By doing this, lighting research may change the world for the better, to be an important topic, not an irrelevance. Keywords: Commentary; Lighting; Vision; Human Health
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Brainard, G. C., Sliney, D., Hanifin, J. P., Glickman, G., Byrne, B., Greeson, J. M., et al. (2008). Sensitivity of the human circadian system to short-wavelength (420-nm) light. J Biol Rhythms, 23(5), 379–386.
Abstract: The circadian and neurobehavioral effects of light are primarily mediated by a retinal ganglion cell photoreceptor in the mammalian eye containing the photopigment melanopsin. Nine action spectrum studies using rodents, monkeys, and humans for these responses indicate peak sensitivities in the blue region of the visible spectrum ranging from 459 to 484 nm, with some disagreement in short-wavelength sensitivity of the spectrum. The aim of this work was to quantify the sensitivity of human volunteers to monochromatic 420-nm light for plasma melatonin suppression. Adult female (n=14) and male (n=12) subjects participated in 2 studies, each employing a within-subjects design. In a fluence-response study, subjects (n=8) were tested with 8 light irradiances at 420 nm ranging over a 4-log unit photon density range of 10(10) to 10(14) photons/cm(2)/sec and 1 dark exposure control night. In the other study, subjects (n=18) completed an experiment comparing melatonin suppression with equal photon doses (1.21 x 10(13) photons/cm(2)/sec) of 420 nm and 460 nm monochromatic light and a dark exposure control night. The first study demonstrated a clear fluence-response relationship between 420-nm light and melatonin suppression (p<0.001) with a half-saturation constant of 2.74 x 10(11) photons/cm(2)/sec. The second study showed that 460-nm light is significantly stronger than 420-nm light for suppressing melatonin (p<0.04). Together, the results clarify the visible short-wavelength sensitivity of the human melatonin suppression action spectrum. This basic physiological finding may be useful for optimizing lighting for therapeutic and other applications.
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