Pub Date : 2022-08-29DOI: 10.1177/14771535221086667
L. Xia, Y. Gu, X. Liu, T. Zhang, R. Xu
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.
{"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}
Pub Date : 2022-08-05DOI: 10.1177/14771535221078765
C. Cajochen, O. Stefani, I. Schöllhorn, D. Lang, SL Chellappa
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.
{"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}
Pub Date : 2022-08-04DOI: 10.1177/14771535211069482
N. Miller, F. Leon, J. Tan, L. Irvin
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.
{"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}
Pub Date : 2022-08-01DOI: 10.1177/14771535221100341
{"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}
Pub Date : 2022-07-24DOI: 10.1177/14771535221101557
H. Li, H. Cai
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.
{"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}
Pub Date : 2022-07-23DOI: 10.1177/14771535221112675
M. Vissenberg, M. Perz, M. Donners, D. Sekulovski
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.
{"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}
Pub Date : 2022-07-21DOI: 10.1177/14771535221115944
Michael P. Royer
{"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}
Pub Date : 2022-07-21DOI: 10.1177/14771535221094277
D. Hou, Y. Ni, Y. Wang, C. Weirich, H. Shen, Y. Lin
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.
本文研究了基于现有指标的颜色歧视,并提出了全球和目标颜色场景的预测因子。30名参与者在21种照明条件下进行了Farnsworth-Munsell 100色相测试。实验结果表明,在Rf-Rg和显色指数-色域面积指数坐标系中,总误差分数(TES)和调整总误差分数(TESadj)的分布均以最优点(100,100)为中心呈圆弧状。在此基础上,提出了基于色彩保真度和色域特征的全局色彩判别分数CDS1和CDS2。结果表明,CDS1 (r = 0.82, p < 0.001)和CDS2 (r = 0.81, p < 0.001)与TES具有良好的线性相关性,CDS1 (r = 0.75, p < 0.001)和CDS2 (r = 0.77, p < 0.001)与TESadj也具有良好的线性相关性。在此基础上,将全局色域划分为红黄、黄绿、绿蓝和蓝红四个局部色彩空间,并利用局部色彩属性(Rcs、local、Rhs、local和Rf、local)构建局部色域中的CDSs (CDSlocal和CDSadj,local)。线性回归结果表明,CDSlocal (r¯= 0。79)和CDSadj,local (r¯= 0)。78)可以有效地预测目标颜色场景的颜色辨别。
{"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}
Pub Date : 2022-07-15DOI: 10.1177/14771535221078763
S. He, Y. Yan
Underexposure to daylight in windowless factories puts assembly-line workers at risk of health problems. To investigate whether the advance light exposure in the early morning and during the lunch break benefits workers’ productivity and night-time sleep, a within-subject experiment was conducted in a factory. Four experimental lighting interventions were provided twice a day before work (8:30–9:00 and 12:00–12:30) for consecutive five workdays, covering two light levels (1440 lx vs. 70 lx), each with two correlated colour temperatures (CCTs) (5300 K vs. 3300 K), plus an additional benchmark dark exposure (4 lx). Participants’ subjective alertness and night-time sleep were measured daily, and the chronotype was monitored once a week. Results showed that a higher illuminance was correlated with increased subjective work alertness and higher sleep efficiency, while a lower CCT slightly improved alertness. The subjective work alertness and sleep efficiency under the two advance bright light exposures were higher than those under the dark exposure, and the responses of subjective alertness were more pronounced in the afternoon than those in the morning. Yet, the chronotype had no evident change in different lighting interventions. The present study indicated that the daily advance light exposure before work could have a delayed effect on participants’ alertness and sleep quality.
在没有窗户的工厂里,日照不足使装配线上的工人面临健康问题的风险。为了研究在清晨和午休时间提前接受光照是否有利于工人的工作效率和夜间睡眠,我们在一家工厂进行了一项受试者内实验。连续五个工作日,每天两次在工作前(8:30-9:00和12:00-12:30)提供四种实验性照明干预,涵盖两个光照水平(1440 lx vs. 70 lx),每个水平都有两个相关色温(cct) (5300 K vs. 3300 K),外加一个额外的基准暗曝光(4 lx)。每天测量参与者的主观警觉性和夜间睡眠时间,每周监测一次时间类型。结果表明,较高的照度与主观工作警觉性增加和睡眠效率提高相关,而较低的CCT则略微改善警觉性。两种提前强光照射下的主观工作警觉性和睡眠效率均高于暗光照射下的主观警觉性,且主观警觉性反应在下午比上午更明显。不同光照干预对睡眠时型无明显影响。目前的研究表明,每天工作前的提前光照可能会对参与者的警觉性和睡眠质量产生延迟效应。
{"title":"Impact of advance light exposure on assembly-line workers’ subjective work alertness and sleep quality","authors":"S. He, Y. Yan","doi":"10.1177/14771535221078763","DOIUrl":"https://doi.org/10.1177/14771535221078763","url":null,"abstract":"Underexposure to daylight in windowless factories puts assembly-line workers at risk of health problems. To investigate whether the advance light exposure in the early morning and during the lunch break benefits workers’ productivity and night-time sleep, a within-subject experiment was conducted in a factory. Four experimental lighting interventions were provided twice a day before work (8:30–9:00 and 12:00–12:30) for consecutive five workdays, covering two light levels (1440 lx vs. 70 lx), each with two correlated colour temperatures (CCTs) (5300 K vs. 3300 K), plus an additional benchmark dark exposure (4 lx). Participants’ subjective alertness and night-time sleep were measured daily, and the chronotype was monitored once a week. Results showed that a higher illuminance was correlated with increased subjective work alertness and higher sleep efficiency, while a lower CCT slightly improved alertness. The subjective work alertness and sleep efficiency under the two advance bright light exposures were higher than those under the dark exposure, and the responses of subjective alertness were more pronounced in the afternoon than those in the morning. Yet, the chronotype had no evident change in different lighting interventions. The present study indicated that the daily advance light exposure before work could have a delayed effect on participants’ alertness and sleep quality.","PeriodicalId":18133,"journal":{"name":"Lighting Research & Technology","volume":"44 1","pages":"105 - 128"},"PeriodicalIF":2.5,"publicationDate":"2022-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78566354","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}
Pub Date : 2022-07-13DOI: 10.1177/14771535221094737
X. Xie, Q. Sun, J. Gong, N. Liao, W. Song
The nonlinear response affects the effect of imaging system response non-uniformity correction (NUC) methods. Most of the methods are effective in a certain range of responses. In this paper, a new NUC method is proposed based on the mechanism of imaging system response non-uniformities production. Optical system-related non-uniformity is described as radiation transmission non-uniformity (RTNU) and detector-related non-uniformity is described as radiation conversion non-uniformity (RCNU). The RTNU is removed by inverse operation and RCNU is removed by regularization optimization. We verify the proposed method with respect to visual effect evaluation of actual scene images and three performance metrics evaluation of statistical F ratio, F-norm roughness and chromatic aberration ellipse. The experimental results verify the effect of our method. The proposed method is effective for NUC in a larger range of responses.
{"title":"Colour imaging system response non-uniformity correction based on inverse model and regularization method","authors":"X. Xie, Q. Sun, J. Gong, N. Liao, W. Song","doi":"10.1177/14771535221094737","DOIUrl":"https://doi.org/10.1177/14771535221094737","url":null,"abstract":"The nonlinear response affects the effect of imaging system response non-uniformity correction (NUC) methods. Most of the methods are effective in a certain range of responses. In this paper, a new NUC method is proposed based on the mechanism of imaging system response non-uniformities production. Optical system-related non-uniformity is described as radiation transmission non-uniformity (RTNU) and detector-related non-uniformity is described as radiation conversion non-uniformity (RCNU). The RTNU is removed by inverse operation and RCNU is removed by regularization optimization. We verify the proposed method with respect to visual effect evaluation of actual scene images and three performance metrics evaluation of statistical F ratio, F-norm roughness and chromatic aberration ellipse. The experimental results verify the effect of our method. The proposed method is effective for NUC in a larger range of responses.","PeriodicalId":18133,"journal":{"name":"Lighting Research & Technology","volume":"10 1","pages":"189 - 203"},"PeriodicalIF":2.5,"publicationDate":"2022-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87943456","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}