Lighting Research & Technology最新文献

{"title":"An examination of range effects when evaluating discomfort due to glare in Singaporean buildings","authors":"MG Kent, J. Jakubiec","doi":"10.1177/14771535211047220","DOIUrl":"https://doi.org/10.1177/14771535211047220","url":null,"abstract":"This article discusses ratings of visual discomfort from glare across different buildings located in Singapore. These data were used to determine if range effects influence the vertical illuminance values for the same ratings of visual discomfort when the category rating procedure is used. The effect occurs when maxima and minima vertical illuminance (i.e. the range) vary across buildings. Our analyses showed that with a higher vertical illuminance range in a building, the mean vertical illuminance value for the same criterion of visual discomfort also increased. The results suggest that the effect caused by different ranges of measured vertical illuminance present across the buildings biased the ratings of visual discomfort. Although these effects may be unavoidable in some buildings that have vastly different levels of light, the data suggest that the overall range of vertical illuminance must be carefully evaluated when predicting visual discomfort. Matching these conditions may enable vertical illuminance to provide more reliable evaluations of discomfort due to glare.","PeriodicalId":18133,"journal":{"name":"Lighting Research & Technology","volume":"44 1","pages":"514 - 528"},"PeriodicalIF":2.5,"publicationDate":"2021-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88285757","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A simple design of uniform LED illumination using catadioptric collimator and freeform lenslet array","authors":"DT Vu, H. Vu, S. Shin, NM Kieu, TQ Tien, NH Vu","doi":"10.1177/14771535211052451","DOIUrl":"https://doi.org/10.1177/14771535211052451","url":null,"abstract":"We introduce a compact lenslet array principle that takes advantage of freeform optics to deploy a light distributor, beneficial for highly efficient, inexpensive, low energy consumption light-emitting diode (LED) lighting system. We outline here a simple strategy for designing the freeform lens that makes use of an array of the identical plano-convex lenslet. The light is redistributed from such lenslet, hinging on the principle of optical path length conservation, and then delivered to the receiver plane. The superimposing of such illumination area from every lenslet occurs on the receiver plane, in which the non-uniform illumination area located in the boundary should have the same dimension as the size of the freeform lenslet array. Such an area, insofar, is negligible due to their small size, which is the crux of our design, representing a large departure from the former implementations. Based on simulations that assess light performance, the proposed design exhibited the compatibility for multiple radiation geometries and off-axis lighting without concern for the initial radiation pattern of the source. As simulated, the LED light source integrated with such proposed freeform lenslet array revealed high luminous efficiency and uniformity within the illumination area of interest were above 70% and 85%, respectively. Such novel design was then experimentally demonstrated to possess a uniformity of 75% at hand, which was close to the simulation results. Also, proposed indoor lighting was implemented in comparison with the commercial LED downlight and LED panel, whereby the energy consumption, number of luminaires and illumination performance were assessed to show the advantage of our simplified model.","PeriodicalId":18133,"journal":{"name":"Lighting Research & Technology","volume":"44 1","pages":"546 - 562"},"PeriodicalIF":2.5,"publicationDate":"2021-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86842853","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Is it possible to achieve quality lighting without considering the photometry of the pavements?","authors":"V. Muzet, S. Liandrat, V. Bour, J. Dehon, J. Christory","doi":"10.1177/14771535221111564","DOIUrl":"https://doi.org/10.1177/14771535221111564","url":null,"abstract":"In this study, the photometry of a wide range of conventional and innovative pavements used in urban and interurban areas was characterised with a laboratory gonioreflectometer, both in new condition and after 30 months of natural ageing. An extreme diversity of behaviour with respect to light reflection has been demonstrated, both over time and between pavements. Various lighting studies have been carried out for cases of renewal of lighting installation with the installation of LED luminaires on poles in place. The calculations have shown that the use of typical CIE r-tables almost systematically leads to non-compliance with the EN 13201 standard, particularly in terms of uniformity. On the other hand, taking into account in the calculations, the photometry of the pavement in its stabilised state makes it possible both to respect the challenges of lighting safety and to achieve significant energy savings. As measurements of pavement photometry are rarely carried out, an alternative is to set up a database of urban pavements, which is one of the achievements of this research.","PeriodicalId":18133,"journal":{"name":"Lighting Research & Technology","volume":"15 1","pages":"345 - 365"},"PeriodicalIF":2.5,"publicationDate":"2021-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74687996","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The effect of changes in light level on the numbers of cyclists","authors":"J. Uttley, S. Fotios, C. Robbins, C. Moscoso","doi":"10.1177/14771535231163815","DOIUrl":"https://doi.org/10.1177/14771535231163815","url":null,"abstract":"Cycling has a range of benefits and should be encouraged, but darkness may put people off from cycling due to reductions in visibility, road safety and personal security. We summarise previous work that consistently demonstrates how darkness reduces the number of people cycling after dark, after accounting for confounding factors such as time of day and seasonal variations in weather. We extend this previous work by analysing cyclist counts in Norway, a country at a higher latitude than those examined previously. An effect of darkness on cycling rates was found but this effect was smaller than that found in previous work, suggesting certain unknown factors may be important in mediating the impact of darkness on cycling rates. One factor that is known to mediate the effect is road lighting. Previous findings indicate that increased illuminance can offset the reductions in cyclists caused by darkness and also that there may be an optimal illuminance after which no further benefits may be achieved.","PeriodicalId":18133,"journal":{"name":"Lighting Research & Technology","volume":"175 1","pages":"366 - 376"},"PeriodicalIF":2.5,"publicationDate":"2021-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77625100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Towards a framework for light-dosimetry studies: Methodological considerations","authors":"S. Hartmeyer, F. Webler, M. Andersen","doi":"10.1177/14771535221103258","DOIUrl":"https://doi.org/10.1177/14771535221103258","url":null,"abstract":"For field research of non-visual effects of light, accurate measurement of personal light exposure is required. A consensus framework for light-dosimetry could improve non-visual field research and ensure comparability between studies. Here, we present a review of methodologies used in non-visual light-dosimetry studies published to date, focussing on considerations regarding the measurement and preparation of personal light exposure data. Overall, a large variability in the studies’ methodologies is observed, highlighting the need for a consensus framework. We propose methodological considerations that should be included in such a framework and that can guide future studies. Furthermore, we highlight important points that should be addressed in future research to ensure compatibility between different dosimetry studies. Taken together, this review effort underlines the importance of a systematic approach to light-dosimetry in order to harness all the power of integrative lighting research in real life.","PeriodicalId":18133,"journal":{"name":"Lighting Research & Technology","volume":"19 1","pages":"377 - 399"},"PeriodicalIF":2.5,"publicationDate":"2021-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84103772","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterization of luminescent road markings","authors":"C. Villa, R. Brémond, F. Eymond, E. Saint-Jacques","doi":"10.1177/14771535221111052","DOIUrl":"https://doi.org/10.1177/14771535221111052","url":null,"abstract":"Photoluminescent paints for road marking application have been evaluated through laboratory measurements and visibility computations. The luminance decay in the dark was measured after constant excitation during at least 6 hours. To study the effect of night-time lighting conditions, luminance was measured under a constant low illumination (simulating moon and light pollution), and a periodic lighting, simulating automotive traffic. Measurements were also carried out on luminescent road marking applied on real pavement in a full-scale mock-up. Then, possible uses and limits of photoluminescent road markings were investigated through visibility computations based on the COST 331 model. Findings suggest luminescent road markings could strengthen the visual guidance of drivers on the road with traffic by increasing the visibility distance beyond the headlamp beams during the first few hours of the night, and in unlit areas such as bicycle paths, but the performance depends on the night-time illumination level.","PeriodicalId":18133,"journal":{"name":"Lighting Research & Technology","volume":"32 1","pages":"459 - 473"},"PeriodicalIF":2.5,"publicationDate":"2021-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84687406","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Editorial: Human-centred integrative lighting and spill-over effects","authors":"M. Aries","doi":"10.1177/14771535211058058","DOIUrl":"https://doi.org/10.1177/14771535211058058","url":null,"abstract":"","PeriodicalId":18133,"journal":{"name":"Lighting Research & Technology","volume":"48 1","pages":"699 - 699"},"PeriodicalIF":2.5,"publicationDate":"2021-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78242207","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Opinion: On the skill to specify","authors":"K. Cuttle","doi":"10.1177/14771535211058059","DOIUrl":"https://doi.org/10.1177/14771535211058059","url":null,"abstract":"It started with the ability to switch it on or off at the flick of a switch. Then we were able to turn it up or down by twisting a knob. Now digital LED technology enables almost any spectral power distribution to be generated; 3-D printing enables luminaires to be produced for specific luminous intensity distributions; and control systems can vary the lighting to suit time of day, season, occupancy, activity, or just peoples’ whims. The capability of lighting providers to produce systems that will perform to precisely defined specifications now far exceeds the ability of practitioners to generate specifications for intended lighting characteristics. I have for some while advocated an approach to lighting practice named the Lighting Design Objectives (LiDOs) Procedure. The lighting practitioner is guided to specify design objectives relating to the quantity and distribution of illumination for an indoor space, and from this, the procedure generates a specification for the spatial distribution of direct luminous flux to optimally achieve the objectives. The practitioner’s chosen objectives may range from efficient utilization of flux to creating a pattern of visual emphasis for selected features, and the procedure leads the practitioner to develop a spatial flux distribution that is unique to the application. This procedure is capable of being developed to incorporate a broader range of lighting design objectives. This would enable a practitioner to develop a set of objectives to describe his or her vision of how lighting is to influence the appearance of a space, its contents, and the people within it, and from this, the procedure would develop a specification that covers the spatial, spectral, and temporal distributions of flux to be provided by the luminaires. The ability to make this transition would enable not only creative designers to express their intentions with increased confidence, but also for research findings relating peoples’ responses to lighting to be readily incorporated into practice. This concept addresses a crucial issue of lighting practice. A lighting designer’s product is not beautiful lighting: it is a lighting specification that forms a basis for competitive tendering. The designer must assume that his or her solution will be installed by the contractor who has come up with the lowest price, and that this price will have been based on their estimate of the least possible amount of time being spent on site. It may also take account of their assessment of the opportunities that the specification offers for cost savings through substitutions and variation orders. The designer’s skill in firstly writing a watertight specification, and then in enforcing it, is crucial for success, but that is not new. What is new is an emerging awareness of the role that skilful specification writing can play in enabling lighting practitioners to gain full advantage of the expanding opportunities offered by our burgeoning technology.","PeriodicalId":18133,"journal":{"name":"Lighting Research & Technology","volume":"16 1","pages":"700 - 700"},"PeriodicalIF":2.5,"publicationDate":"2021-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82670303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Gaze correlates of view preference: Comparing natural and urban scenes","authors":"A. Batool, P. Rutherford, P. McGraw, T. Ledgeway, S. Altomonte","doi":"10.1177/14771535211055703","DOIUrl":"https://doi.org/10.1177/14771535211055703","url":null,"abstract":"When looking out of a window, natural views are usually associated with restorative qualities and are given a higher preference than urban scenes. Previous research has shown that gaze behaviour might differ based on the natural or urban content of views. A lower number of fixations has been associated with the aesthetic evaluation of natural scenes while, when looking at an urban environment, a high preference has been correlated with more exploratory gaze behaviours. To characterise gaze correlates of view preference across natural and urban scenes, we collected and analysed experimental data featuring subjective preference ratings, eye-tracking measures, verbal reasoning associated with preference and nature relatedness scores. Consistent with the literature, our results confirm that natural scenes are more preferred than urban views and that gaze behaviours depend on view type and preference. Observing natural scenes was characterised by lower numbers of fixations and saccades, and longer fixation durations, compared to urban views. However, for both view types, most preferred scenes led to more fixations and saccades. Our findings also showed that nature relatedness may be correlated with visual exploration of scenes. Individual preferences and personality attributes, therefore, should be accounted for in studies on view preference and gaze behaviour.","PeriodicalId":18133,"journal":{"name":"Lighting Research & Technology","volume":"38 1","pages":"576 - 594"},"PeriodicalIF":2.5,"publicationDate":"2021-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88350483","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A 24-hour lighting scheme to promote alertness and circadian entrainment in railroad dispatchers on rotating shifts: A field study","authors":"L. Şahin, M. Figueiro","doi":"10.1177/14771535211040985","DOIUrl":"https://doi.org/10.1177/14771535211040985","url":null,"abstract":"Shift-working railway personnel are highly susceptible to fatigue stemming from poor-quality sleep that can impair the performance of safety-critical functions. Disruption of the 24-h light–dark pattern incident on the retinae appears to play a central role in exacerbating these problems, especially with respect to exposure to light at night and circadian rhythms disruption. This field study tested and demonstrated the effectiveness and acceptability of an intervention (red and blue light combined with white light) to (1) promote circadian alignment, (2) advance the timing of dim light melatonin onset, (3) improve objective and subjective sleep quality, and (4) reduce subjective sleepiness in an operational context compared to a baseline (conventional lighting) condition. The lighting intervention promoted significantly greater synchrony between day-shift participants’ light–dark exposures and rest–activity patterns, but did not significantly advance the timing of dim light melatonin onset. The intervention was also associated with reduced objective sleep disturbances and improved (albeit less robustly) subjective sleep quality, but it only reduced participants’ subjective sleepiness while they were off duty during the day shift. This research demonstrates that lighting interventions can promote circadian alignment and improve sleep quality among railway shift workers and may be translatable to other 24-h industries.","PeriodicalId":18133,"journal":{"name":"Lighting Research & Technology","volume":"41 1","pages":"441 - 457"},"PeriodicalIF":2.5,"publicationDate":"2021-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81882377","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}