{"title":"Extending the lighting design objectives procedure for holistic lighting solutions","authors":"C. Cuttle","doi":"10.1177/14771535211061044","DOIUrl":"https://doi.org/10.1177/14771535211061044","url":null,"abstract":"The author has previously proposed a novel spreadsheet-based lighting design objectives procedure (LiDOs) that enables practitioners to reconcile interacting LiDOs relating to the spatial distribution of illumination within a space, and this procedure has been successfully adopted by several lighting design practices. This paper proposes that the procedure is developed into an extended computer-based lighting design tool (LiDOs2) that includes LiDOs relating to spectral and temporal illumination distributions, as well as spatial distribution. This would enable regulators to specify limiting values for basic indoor lighting objectives such as perceived adequacy of illumination while at the same time guiding practitioners to incorporate LiDOs that address characteristics of lighting chosen to suit specific applications. The LiDOs2 procedure would be capable of generating holistic lighting performance specifications that would enable practitioners to conduct informed searches for light sources and luminaires, and to determine layouts and control circuits with confidence that the specified combination of LiDOs would be achieved.","PeriodicalId":18133,"journal":{"name":"Lighting Research & Technology","volume":"49 1","pages":"631 - 656"},"PeriodicalIF":2.5,"publicationDate":"2022-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84571515","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":"From luminance to brightness: A data-driven approach to support brightness assessments in open plan offices","authors":"A. de Vries, I. Heynderickx, Y. D. de Kort","doi":"10.1177/14771535221117365","DOIUrl":"https://doi.org/10.1177/14771535221117365","url":null,"abstract":"People can instantly distinguish a brighter from a darker environment, but it is still unknown how to estimate brightness from the luminance distribution in complex visual scenes. In this study, we performed a meta-analysis of three experiments in which participants assessed brightness in an open plan office environment. Experiment 1 varied the luminance distribution on the wall, Experiment 2 varied the desk illuminance and Experiment 3 varied the ceiling illumination. Correlating various measures derived from high-resolution luminance images with participants’ brightness ratings, we investigated to what extent brightness could be predicted. In particular, we focused on 19 different luminance distribution characteristics calculated over 11 different areas of the visual field. In line with earlier work, participants could be grouped in two categories, one consisting of participants who substantially and consistently varied in their brightness assessments for the different settings, and the other consisting of participants who responded more evenly, regardless of the setting. Based on the brightness-responsive group of participants, brightness could be best modelled with the logarithm of the median luminance calculated over a 60° horizontal band in the field of view or with the logarithm of the 95th percentile over the median calculated over the 40° horizontal band, explaining, respectively, 38% and 35% of the variance in brightness perception.","PeriodicalId":18133,"journal":{"name":"Lighting Research & Technology","volume":"33 1","pages":"798 - 818"},"PeriodicalIF":2.5,"publicationDate":"2022-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81667934","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":"Determining scalar illuminance from cubic illuminance data. Part 2: Tests in real lighting environments and an approach to improve its accuracy","authors":"L. Xia, Y. Gu, X. Liu, T. Zhang, R. Xu","doi":"10.1177/14771535221086667","DOIUrl":"https://doi.org/10.1177/14771535221086667","url":null,"abstract":"Scalar illuminance, which describes the constant illumination from all directions, is an important indicator of the abundance of light for a lit object and the adequacy of illumination perceived. This paper proposes a more reliable method to recover scalar illuminance based on tests in natural complex lighting environments. The performance of Cuttle’s Approach 1, Mangkuto’s Approach 2 and Approach 3, together with Xia et al.’s potential Approach 4, were tested under a total of 610 high dynamic range (HDR) panoramic maps of real scenes. The relationships between predicted scalar illuminance and normalised diffuseness levels were checked. The results indicate that the potential Approach 4 is more robust to the cubic meter’s postures, and the predicted scalar illuminance has a regular relationship with normalised diffuseness levels. Approach 4 was corrected, together with Approach 1, formulating a new method named Approach 5S. Later, the proposed Approach 5S was evaluated under 205 indoor and 2233 outdoor panoramas from the Laval HDR databases, and it was shown to recover more reliable scalar illuminance with an average error within 5% in general. This study has provided a practical solution to more accurate vector illuminance-based metrics in real lighting environments. This algorithm can be further integrated into the development of cubic illumination meter instruments.","PeriodicalId":18133,"journal":{"name":"Lighting Research & Technology","volume":"55 1","pages":"62 - 78"},"PeriodicalIF":2.5,"publicationDate":"2022-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81927115","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}
C. Cajochen, O. Stefani, I. Schöllhorn, D. Lang, SL Chellappa
{"title":"Influence of evening light exposure on polysomnographically assessed night-time sleep: A systematic review with meta-analysis","authors":"C. Cajochen, O. Stefani, I. Schöllhorn, D. Lang, SL Chellappa","doi":"10.1177/14771535221078765","DOIUrl":"https://doi.org/10.1177/14771535221078765","url":null,"abstract":"Evening exposure to electric light can acutely suppress melatonin levels and adversely affect subsequent sleep. We conducted a systematic review with meta-analysis investigating the influence of evening illuminance levels on polysomnographically (PSG)-assessed sleep. We also explored how melanopsin (expressed in melanopic equivalent daylight illuminance (EDI) affects human sleep features. We included polysomnographic laboratory sleep studies with healthy humans for effects of illuminance and exposure duration, for pre-sleep exposures between 6:00 p.m. to 1:00 a.m. From 440 identified articles, 114 met eligibility criteria for screening, and 21 also reported type of light source/spectral characteristics, with 12 identified as eligible for review. Meta-analysis showed evening light affects sleep latency, sleep efficiency and slow wave sleep, with overall effect sizes (95% confidence interval) of 0.69 (−0.50; 1.88), 0.34 (−0.13; 0.82) and −0.61 (−1.85; 0.62), respectively. Estimated melanopic EDI in the range of 100–1000 lx yielded clear dose–response relationships for sleep latency and sleep efficiency, but not for slow wave sleep. Whilst illuminance and duration indicated no apparent effects for a single evening light exposure on PSG-assessed sleep latency, sleep efficiency and slow wave sleep, we observed evidence for a relationship between light exposure and sleep effects based on melanopic EDI. Hence, melanopic EDI may provide a robust predictor of non-visual responses on human sleep.","PeriodicalId":18133,"journal":{"name":"Lighting Research & Technology","volume":"10 1","pages":"609 - 624"},"PeriodicalIF":2.5,"publicationDate":"2022-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90074041","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":"Flicker: A review of temporal light modulation stimulus, responses, and measures","authors":"N. Miller, F. Leon, J. Tan, L. Irvin","doi":"10.1177/14771535211069482","DOIUrl":"https://doi.org/10.1177/14771535211069482","url":null,"abstract":"Flicker has been an important lighting system consideration for over a century. More precise terms are temporal light modulation (TLM) as the stimulus, and responses to TLM as the unwanted visual, cognitive, or physiological consequences. As lighting technology evolved, different forms of TLM emerged, and so did responses to them. Today, some LED systems – encompassing the LED, driver, and control – can result in TLM causing severe unwanted effects, while other LED systems produce no unwanted effects at all. LED systems can deliver a much wider range of luminous waveforms than conventional lighting systems, some exhibiting very high modulation depths. More than any light source before, they can elicit perceptions of the phantom array. Direct flicker effects at modulation frequencies less than about 80 Hz and the stroboscopic effect at frequencies greater than 80 Hz are fairly well understood, but the phantom array effect needs more exploration and characterisation. This review focuses on the technology and research history that led to current metrics for quantifying TLM and human responses to TLM. Visually impaired individuals may exhibit alterations in their response to TLM, but such a discussion is beyond the intent of this review. Thus, the focus is on individuals with normal visual function.","PeriodicalId":18133,"journal":{"name":"Lighting Research & Technology","volume":"63 4","pages":"5 - 35"},"PeriodicalIF":2.5,"publicationDate":"2022-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72496930","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":"Corrigendum to Redistribution of luminance patterns on standard sky types","authors":"","doi":"10.1177/14771535221100341","DOIUrl":"https://doi.org/10.1177/14771535221100341","url":null,"abstract":"","PeriodicalId":18133,"journal":{"name":"Lighting Research & Technology","volume":"18 4","pages":"509 - 509"},"PeriodicalIF":2.5,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72491996","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":"Lighting measurement with a 360° panoramic camera: Part 1 – Technical procedure and validation","authors":"H. Li, H. Cai","doi":"10.1177/14771535221101557","DOIUrl":"https://doi.org/10.1177/14771535221101557","url":null,"abstract":"This study developed a 360° field of view (FOV) lighting measurement method with the aid of the Ricoh Theta Z1 panoramic camera. As versatile lighting information from all viewing directions within 360° FOV can be retrieved from a single 360° high dynamic range (HDR) image, this new method improves the lighting measurement efficiency. Part 1 of this study reported in the present paper focuses on technical procedure and validation. Firstly, all technical issues were solved for using the Theta Z1 camera to conduct 360° FOV lighting measurement with a provided and validated step-by-step procedure. A new illuminance measurement method was then developed with the aid of the Theta Z1 camera for calculating all directional illuminance data at the camera measurement point from any viewing direction within the 360° panoramic FOV, retrieved from a single 360° HDR image taken in the field. This 360° FOV lighting measurement method has average error rate of 4.0% ± 2.4% for luminance measurement and 3.1% ± 2.6% for illuminance measurement in building interiors. Reported outcomes include the detailed procedure and algorithms for the configuration, calibrations and post-image processing, and corresponding MATLAB code and Python programs are shared online.","PeriodicalId":18133,"journal":{"name":"Lighting Research & Technology","volume":"1 1","pages":"694 - 711"},"PeriodicalIF":2.5,"publicationDate":"2022-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82204279","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 generic, visual system-based model for discomfort from glare","authors":"M. Vissenberg, M. Perz, M. Donners, D. Sekulovski","doi":"10.1177/14771535221112675","DOIUrl":"https://doi.org/10.1177/14771535221112675","url":null,"abstract":"Conventional measures of discomfort from glare are based on glare source properties like luminous intensity or luminance and typically are valid only to specific situations and to specific types of light sources. For instance, the unified glare rating (UGR) is intended for indoor lighting conditions with medium-sized glare sources, whereas another class of glare measures is specifically devoted to car headlamps. Recently, CIE TC 3-57 started with the aim to develop a more generic glare sensation model based on the human visual system. We present an example of such a model, including a detailed description of aspects like pupil constriction, retinal image formation, photoreceptor response and adaptation, receptive field-type filtering in the retina and neural spatial summation. The linear correlation of the model to UGR in an indoor setting and to subjective glare responses in an outdoor-like setting indicate that the human-visual-system-based model may indeed be considered generic.","PeriodicalId":18133,"journal":{"name":"Lighting Research & Technology","volume":"83 1","pages":"400 - 413"},"PeriodicalIF":2.5,"publicationDate":"2022-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74520494","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: What can we learn from the lighting in homes?","authors":"Michael P. Royer","doi":"10.1177/14771535221115944","DOIUrl":"https://doi.org/10.1177/14771535221115944","url":null,"abstract":"","PeriodicalId":18133,"journal":{"name":"Lighting Research & Technology","volume":"16 1","pages":"411 - 411"},"PeriodicalIF":2.5,"publicationDate":"2022-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80540994","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}
D. Hou, Y. Ni, Y. Wang, C. Weirich, H. Shen, Y. Lin
{"title":"Colour discrimination scores combining colour fidelity and gamut area characteristics","authors":"D. Hou, Y. Ni, Y. Wang, C. Weirich, H. Shen, Y. Lin","doi":"10.1177/14771535221094277","DOIUrl":"https://doi.org/10.1177/14771535221094277","url":null,"abstract":"This paper investigated colour discrimination based on current available indexes, and predictors were proposed for global and targeted colour scenarios. Thirty participants conducted the Farnsworth–Munsell 100 hue test under 21 lighting conditions. The experiment results revealed that the distribution of total error score (TES) and adjusted total error score (TESadj) showed arc shapes centred on the optimal point (100, 100) in both Rf–Rg and colour rendering index–gamut area index coordinate systems. On this basis, global colour discrimination scores, CDS1 and CDS2, based on the colour fidelity and colour gamut characteristics, were proposed. The results demonstrated that both CDS1 (r = 0.82, p < 0.001) and CDS2 (r = 0.81, p < 0.001) provided good linear correlations with TES, and CDS1 (r = 0.75, p < 0.001) and CDS2 (r = 0.77, p < 0.001) also exhibited a good linear correlation with TESadj. Furthermore, the global colour gamut was divided into four local colour spaces (red–yellow, yellow–green, green–blue and blue–red), and the CDSs in the local gamut (CDSlocal and CDSadj,local) were constructed using the local colour properties, including Rcs,local, Rhs,local and Rf,local. The linear regression results demonstrated that CDSlocal ( r ¯ = 0 . 79 ) and CDSadj,local ( r ¯ = 0 . 78 ) can be effective colour discrimination predictors for the targeted colour scenarios.","PeriodicalId":18133,"journal":{"name":"Lighting Research & Technology","volume":"96 1","pages":"129 - 154"},"PeriodicalIF":2.5,"publicationDate":"2022-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85259393","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}