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Flash sequences appear as steady emission of light if the frequency is above the flicker‐fusion threshold. One can display flicker‐fused letters against a background, and using the Talbot‐Plateau law, vary the average luminance of the letters to control degree of match to background luminance. We have previously reported that the visual system can identify letters that have an average luminance that equals background luminance, which can be described as an anomalous contrast discrimination. The present work confirms the earlier report, and provides additional evidence that the phenomenon is not based on a shift in luminance balance. We discuss the possible role of ON and OFF retinal channels in registering the anomalous contrast. [ABSTRACT FROM AUTHOR]

Luminance is the fundamental photometric quantity representing the technical meaning of brightness. It is usually measured from a distance using a matrix sensor, which is the basis of the professional instrument. However, specific technical requirements must be fulfilled to achieve accurate results. This paper considers whether modern high-resolution smartphone cameras are suitable for luminance measurements. Three cameras from high-end smartphones were evaluated on a dedicated laboratory stand. The sensors' output characteristics showed relatively good linearity of the individual R, G, and B channels. Unfortunately, the spectral sensitivities were unfavorable, as the minimum error achieved was about 17%. This device is classified outside the generally accepted quality scale for photometric instruments. The presented investigation confirmed that none of the high-resolution smartphone cameras tested was suitable for use as a universal luminance camera. However, one of the test devices can be developmental if restrictively calibrated and used only in a specialistic laboratory stand. Using a smartphone (or only its camera) for luminance measurements requires proper advanced calibration. It is possible, but it limits us to only dedicated applications. The pilot study presented in this paper will help create a suitable test stand for spectacle vision systems, e.g., virtual reality equipment. [ABSTRACT FROM AUTHOR]

Purpose: Our aim was to explore the effect of ambient lighting on the pattern ERG (PERG). Methods: We compared PERGs recorded in two conditions; room lights on and room lights off. PERGs from 21 adult participants were recorded from each eye to high contrast checks of 50' side width, reversing 3rps in a large (30°) and then standard (15°) field. This was performed first in lights-ON conditions, then 2 min after the room lights were switched off. A minimum of 2 averages of 300 trials were acquired for each condition. A subset of 10 participants had PERGs recorded to a 50' check width with a range of stimulus contrasts (96–18%), also to a range of different check widths (100'–12') at high contrast in both ambient lighting conditions in a 30° field. Results: The lights-ON P50 median peak time (PT) was 3 ms earlier than the lights-OFF P50 from the 30° field (range 0–5 ms) and 15° field (range 0–6 ms). The earlier lights-ON P50 PT was evident at different stimulus contrasts, even after accounting for stimulus contrast reductions associated with stray ambient lighting in lights-ON conditions. Lights-OFF and lights-ON P50 PT were similar to different check widths; the lights-OFF P50 PT to a 50' check width matched the lights-ON P50 PT to a 25' check width. Conclusion: PERG P50 PT in lights-ON ambient light conditions can be earlier than in lights-OFF ambient light conditions. The difference in P50 PT with ambient light may reflect alterations in spatial sensitivity associated with retinal adaptation. These results emphasise the clinical importance of consistent ambient lighting for PERG recording and calibration. [ABSTRACT FROM AUTHOR]

Recessed pavement markings are consistently utilized to withstand the impact of snowplowing and sanding operations, particularly in regions with cold climates. However, the optimal configuration of recessed pavement markings remains inadequately investigated. The objective of this study is to address this concern by conducting an assessment of the luminance of recessed pavement markings. For considering the visual demands of drivers, a luminance evaluation method based on digital imagery was implemented at first. Recessed pavement markings with various configurations were then prepared, and their luminance was simultaneously measured. The luminance of recessed pavement markings after service simulation was assessed to elucidate the luminance deterioration laws. Finally, the retroreflectivity of recessed pavement markings was evaluated for their comparative analysis and better employment. Based on the luminance deterioration with operation time as an indicator, recessed pavement markings with a thickness exceeding 0.5 mm and flush with the surface exhibited a service life twice as long as conventional pavement markings. The quantitative relationship between critical values of retroreflectivity and luminance was established [retroreflected luminance (RL) of 80 mcd·m−2·lx−1 corresponds to luminance of 200 cd/m2 ], and the minimum RL of recessed pavement markings should be as low as 90 mcd·m−2·lx−1 for practical application. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study is to investigate the effect of visual obstruction when a head-up display (HUD) is presented in front of a driver's field of view. Background: The use of HUDs is expected to increase due to advances in augmented reality (AR) technology. A conventional HUD is displayed at a relatively low position in relation to the driver's viewpoint and has little effect on their front view. However, while an HUD, such as the AR-HUD, is presented in front of the driver's field of vision and helps them in presenting ADAS information, there is a concern that this display may obscure visual objects on the road from the driver's field of vision. Method: An experiment using a mockup consisting of a HUD and a driver's seat was conducted with 28 participants. A passenger car, motorcycle, and crossing pedestrian were presented as visual objects on a 65-in monitor behind the image of the HUD. Participants were asked questions under different conditions with changes in the HUD luminance and asked to correctly answer questions regarding changes in the inter-vehicle distance and the existence of visual objects on the road. The number of correct answers provided by the participants was recorded. Results: The experimental results revealed that the HUD had an effect under the twilight condition wherein the background luminance was low. Furthermore, analyzing the number of correct answers for each visual target revealed that the HUD had an effect under conditions wherein the size of the visual object was small. Conclusion: It was experimentally derived that the luminance ratio Rluminance = 1.1 was the threshold value that affected the recognition of the visual object in the background when the HUD was presented in front of the driver's field of view. Implication: The threshold value of the luminance ratio Rluminance obtained in this study can be considered when deciding how to properly display the HUD in front of the driver's field of view.

Single-sample face and ear recognition (SSFER) is a challenging sub-problem in biometric recognition that refers to the difficulty in feature extraction and classification when only a single-face or ear training image is available. SSFER becomes much more challenging when images contain a variety of lighting, positions, occlusions, expressions, etc. Virtual sample generation methods in SSFER have gained popularity among researchers due to their simplicity in the augmentation of training sets and improved feature extraction. In this article, we propose a novel and simple method for the generation of virtual samples for training the classifiers to be used in SSFER. The proposed method is based on 2D local patches, and six training samples are generated for a single face or ear image. Further, training is performed using one of the variations along with its generated virtual samples, while during testing, all the variations were considered except the one used during training. Features are extracted using principal component analysis, and classification is performed using the nearest-neighbour classifier. Extensive experiments were performed for the image quality of the virtual samples, classification accuracy, and testing time on ORL, Yale, and AR (illumination) face databases, and AMI and IITD ear databases which are publicly available. The results are also compared with other state-of-the-art methods, with classification accuracy and universal image quality being the major outcomes. The proposed method improves the classification accuracy by 14.50%, 1.11%, 0.09%, 21.60%, and 10.00% on AR (illumination), Yale, ORL, IITD, and AMI databases, respectively. The proposed method showed an improvement in universal image quality by 15%, 20%, 14%, 30%, and 15% on AR (illumination), Yale, ORL, IITD, and AMI databases, respectively. Experimental results prove the effectiveness of the proposed method in generating virtual samples for SSFER. [ABSTRACT FROM AUTHOR]

The Talbot–Plateau law specifies what combinations of flash frequency, duration, and intensity will yield a flicker‐fused stimulus that matches the brightness of a steady stimulus. It has proven to be remarkably robust in its predictions, and here we provide additional support though the use of a contrast discrimination task. However, we also find that the visual system can register flicker‐fused letters when the combination of frequency and duration is relatively low. The letters are recognized even though they have the same physical luminance as background. We hypothesize that the letters elicit synchronous oscillations that encode for stimulus attributes, which prevents the letter from blending into the background. [ABSTRACT FROM AUTHOR]

Texture segregation studies indicate that some types of textures are processed by edge-based and others by region-based mechanisms. However, studies employing nominally edge-based textures have found evidence for region-based processing mechanisms when the task was to detect rather than segregate the textures. Here we investigate directly whether the nature of the task determines if region-based or edge-based mechanisms are involved in texture perception. Stimuli consisted of randomly positioned Gabor micropattern texture arrays with five types of modulation: orientation modulation, orientation variance modulation, luminance modulation, contrast modulation and contrast variance modulation (CVM). There were four modulation frequencies: 0.1, 0.2, 0.4 and 0.8 cpd. Each modulation type was defined by three types of waveforms: sinewave (SN) with its smooth variations, square-wave (SQ) and cusp-wave (CS) with its sharp texture edges. The CS waveform was constructed by removing a sinewave from an equal amplitude square-wave. Participants performed two tasks: detection in which participants selected which of two stimuli contained the modulation and discrimination in which participants indicated which of two textures had a different modulation orientation. Our results indicate that threshold amplitudes in the detection task followed the ordering SQ < SN < CS across all spatial frequencies, consistent with detection being mediated by the overall energy in the stimulus and hence region based. With the discrimination task at low texture spatial frequencies and with CVM textures at all spatial frequencies the order was CS ≤ SQ with both < SN, consistent with being edge-based. We modeled the data by estimating the spatial frequency of a Difference of Gaussian filter that gave the largest peak amplitude response to the data. We found that the peak amplitude was lower for detection than discrimination across all texture types except for the CVM texture. We conclude that task requirements are critical to whether edges or regions underpin texture processing. [ABSTRACT FROM AUTHOR]

Flexible inorganic electroluminescent devices exhibit high luminous efficiency, rapid response, low production costs and stable luminescence. These devices can be employed for flexible displays, intelligent sensing and other functions, making them promising candidates for applications in smartphones, electronic skin and smart wearables. Textile materials, with their flexibility, wearability, and well-established processing techniques, serve as excellent substrates for these flexible electroluminescent devices. In recent years, the structural design of flexible inorganic electroluminescent devices has matured significantly, driving research and development efforts across a wide range of applications, particularly in wearable electronics, displays and bionic robots. Electroluminescence primarily arises when a current passes through a substance, causing it to emit light under a strong electric field. Two main types of electroluminescence exist: injection electroluminescence and intrinsic electroluminescence. In the case of injection electroluminescence (also known as low-field electroluminescence), electrons and holes are directly injected from the electrodes into the crystal. When these charge carriers recombine within the crystal, excess energy is released in the form of light. Intrinsic electroluminescence (or high-field electroluminescence) is akin to an in vivo luminescence effect. In inorganic electroluminescent materials, electrons gain energy and collide with and excite luminescent centers under high electric fields. Consequently, the excited electrons in the luminescent centers transition to lower energy states, emitting light. Currently, the most widely used inorganic electroluminescent materials included zinc sulfide-based compounds and perovskite materials. Zinc sulfide exhibits excellent thermal stability, mechanical strength and high carrier mobility, making it a common choice for thin-film transistors and other electronic devices. Doping zinc sulfide with metal elements (such as copper, aluminum or manganese) allows for the creation of different variants, such as zinc sulfide: copper (green) and zinc sulfide: manganese (orange), enabling tunable emission colors by adjusting the frequency of the AC electric field. However, localized electric field breakdown remains a challenge, leading to device damage. Perovskite materials offer adjustable band gaps, narrow half-peak widths, high carrier mobility and efficient fluorescence. When used as the light- emitting layer in perovskite light-emitting diodes, they exhibit high color purity, brightness and a wide color gamut. By modifying the composition of halide ions and adjusting cation proportions, the optical and electrical properties of perovskite can be tailored, showing promise in lighting and display applications. Nevertheless, challenges related to stability, mechanical properties, toxicity, and large-scale manufacturing persist for flexible perovskite electroluminescent materials As demand grows for convenient solutions, electroluminescent devices are expected to serve additional functions, including health monitoring, electronic communication and aerospace applications. Among these, textile displays play a crucial role in transmitting information anytime and anywhere. Wearable electronic products integrated into shoes, clothing and watches enhance human convenience. The acquisition and display of textile electroluminescent devices rely on luminous fabrics and fibers, utilizing printing, coating, lamination and fiber weaving technologies. These methods impose stringent requirements on brightness and device lifespan, necessitating improved device structures and combination modes to achieve stable and durable performance in textile applications. At present, large-scale continuous production of flexible inorganic electroluminescent devices remains a challenge. As new display applications emerge, stricter demands are placed on flexible electroluminescent devices. In flexible inorganic electroluminescent devices, the development and application of electroluminescent devices need to be combined with other disciplines to develop a multifunctional device to meet people's needs. [ABSTRACT FROM AUTHOR]

Designing the floodlighting of objects in the context of improving the night image of the city is a very complex task, requiring not only a time commitment but also precise analysis and innovative solutions. In particular, designers must consider the principles of aesthetics and adapt the lighting to the architectural style and details of the facilities while ensuring energy efficiency and minimising the impact on the natural environment. For single objects, the task is relatively simple. The problem arises when the task is to develop a lighting concept for a large ensemble. Computer applications strictly dedicated to lighting analysis cannot capture a 3D model rich in architectural detail. The article presents a case study that focuses on a comprehensive approach to designing the floodlighting of a complex of architectural objects. The steps for designing the floodlighting of objects are presented. Based on a computer simulation, a visual lighting concept and a detailed analysis of the luminance distribution and floodlighting efficiency were presented. The obtained average luminance levels are consistent with recommendations and standards, and the project is characterised by a high lighting efficiency of 56%. This approach enables an understanding of how light affects architectural structures and the surroundings, which is crucial to achieving harmony between the technical side of the project and its aesthetics. The project presented in the article is an inspiring example of how a comprehensive approach to illumination can contribute to creating an attractive night landscape of the city, taking into account the aspects of sustainable development. This is very important nowadays, when the floodlighting of architectural objects is often considered an element of the landscape that can be omitted. [ABSTRACT FROM AUTHOR]

The incorporation of luminescent lanthanide complexes in inorganic matrices opens appealing possibilities in the rational upstream conception of new luminescent materials with easier recyclability. In this regard, the influence of SBA‐15 mesoporous silica, as a host matrix, on the photophysical properties of europium‐trisdipicolinate cesium salt is investigated. The lanthanide complex can be completely and reversibly adsorbed on the silica, using incipient wetness impregnation (IWI) in WATER, without the need of anchoring groups or covalent bonding on the silica surface. This specific procedure allows the homogeneous dispersion of the lanthanide complex into the host silica matrix. Appropriately assessing the photophysical properties of the targeted luminescent material proved remarkably challenging, demanding utmost caution, particularly due to the strong scattering of the mesoporous matrices. Additionally, while the observations confirm an important increase of luminescence lifetimes of lanthanide complexes upon integration into these mediums, this variation is attributed to the differing refractive indexes and not to specific surface interactions or confinement effect. Indeed, it appeared that previous literature precedents depicted erroneous exhalations of the complexes intrinsic quantum yield due to the repeated use of erroneous refractive index values. In the meantime, the luminance of these materials under UV irradiation improves drastically in comparison to what is obtained with the physical dispersion of micro‐crystals of the lanthanide complex onto silica. It is demonstrated that this improvement is due to a reduced inner filter effect in the adsorbed samples. In this regard, IWI of lanthanide complexes in the mesoporous matrices method could be of interest in the development of recyclable emitting layers, less demanding in terms of emitter quantity. [ABSTRACT FROM AUTHOR]

Closing our eyes largely shuts down our ability to see. That said, our eyelids still pass some light, allowing our visual system to coarsely process information about visual scenes, such as changes in luminance. However, the specific impact of eye closure on processing within the early visual system remains largely unknown. To understand how visual processing is modulated when eyes are shut, we used functional magnetic resonance imaging (fMRI) to measure responses to a flickering visual stimulus at high (100%) and low (10%) temporal contrasts, while participants viewed the stimuli with their eyes open or closed. Interestingly, we discovered that eye closure produced a qualitatively distinct pattern of effects across the visual thalamus and visual cortex. We found that with eyes open, low temporal contrast stimuli produced smaller responses across the lateral geniculate nucleus (LGN), primary (V1) and extrastriate visual cortex (V2). However, with eyes closed, we discovered that the LGN and V1 maintained similar blood oxygenation level-dependent (BOLD) responses as the eyes open condition, despite the suppressed visual input through the eyelid. In contrast, V2 and V3 had strongly attenuated BOLD response when eyes were closed, regardless of temporal contrast. Our findings reveal a qualitatively distinct pattern of visual processing when the eyes are closed—one that is not simply an overall attenuation but rather reflects distinct responses across visual thalamocortical networks, wherein the earliest stages of processing preserve information about stimuli but are then gated off downstream in visual cortex. NEW & NOTEWORTHY: When we close our eyes coarse luminance information is still accessible by the visual system. Using functional magnetic resonance imaging, we examined whether eyelid closure plays a unique role in visual processing. We discovered that while the LGN and V1 show equivalent responses when the eyes are open or closed, extrastriate cortex exhibited attenuated responses with eye closure. This suggests that when the eyes are closed, downstream visual processing is blind to this information. [ABSTRACT FROM AUTHOR]

Our eyes execute rapid, directional movements known as saccades, occurring several times per second, to focus on objects of interest in our environment. During these movements, visual sensitivity is temporarily reduced. Despite numerous studies on this topic, the underlying mechanism remains elusive, including a lingering debate on whether saccadic suppression affects the parvocellular visual pathway. To address this issue, we conducted a study employing steady-state visual evoked potentials (SSVEPs) elicited by chromatic and luminance stimuli while observers performed saccadic eye movements. We also employed an innovative analysis pipeline to enhance the signal-to-noise ratio, yielding superior results compared to the previous method. Our findings revealed a clear suppression effect on SSVEP signals during saccades compared to fixation periods. Notably, this suppression effect was comparable for both chromatic and luminance stimuli. We went further to measure the suppression effect across various contrast levels, which enabled us to model SSVEP responses with contrast response functions. The results suggest that saccades primarily reduce response gain without significantly affecting contrast gain and that this reduction applies uniformly to both chromatic and luminance pathways. In summary, our study provides robust evidence that saccades similarly suppress visual processing in both the parvocellular and magnocellular pathways within the human early visual cortex, as indicated by SSVEP responses. The observation that saccadic eye movements impact response gain rather than contrast gain implies that they influence visual processing through a multiplicative mechanism. NEW & NOTEWORTHY: The present study demonstrates that saccadic eye movements reduce the processing of both luminance and chromatic stimuli in the early visual cortex of humans. By modeling the contrast response function, the study further shows that saccades affect visual processing by reducing the response gain rather than altering the contrast gain, suggesting that a multiplicative mechanism of visual attenuation affects both parvocellular and magnocellular pathways. [ABSTRACT FROM AUTHOR]

Differences in visual comfort between comfortable and uncomfortable luminance were explored on a smartphone. The results revealed that tiny changes in CFF and microsaccade parameters (pupil diameter, amplitude, and peak velocity) were presented at the comfortable luminance, inducing less eye discomfort. Particularly, CFF is an effective indicator of visual comfort and fatigue. [ABSTRACT FROM AUTHOR]

Understanding OLED life characteristics is crucial towards implementation of OLED technology into automotive applications. The use of the Arrhenius equation together with the Inverse Power Law may be utilized to estimate the improvement in OLED life when automatic luminance control methods are utilized. [ABSTRACT FROM AUTHOR]

We propose an autostereoscopic display with a directional backlight unit using an interleaved lens array and an organic electroluminescent display as an active light source. In the proposed system, the screen luminance per unit of power consumption is enhanced and the uniformity of luminance is improved. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the change in the vault of the implantable collamer lens (ICL) under dark-to-light conditions and its association with anterior chamber and lens parameters in patients undergoing ICL surgery. Methods: In 76 eyes from 40 patients, preoperative anterior chamber volume (ACV), pupil diameter (PD), anterior chamber angle, central corneal thickness (CCT), white-to-white (WTW), lens thickness (LT), axial length (AL), spherical equivalent (SE) and patient's age were collected. Postoperative vault, PD and LT were measured under dark and light conditions using anterior segment optical coherence tomography (CASIA2; TOMEY, Japan), and changes and lens displacement under dark-to-light conditions were calculated. Mixed-effects models were used to analyze the correlation between the vault change and the anterior chamber and lens parameters of all subjects and the high-vault subgroup. Results: The vault under light condition (648.36 ± 304.47 μm) was significantly smaller compared to the vault under dark condition (708.89 ± 316.15 μm). In all patients, vault change increased with the increase of age, lens displacement and PD change; and increased with the decrease of ACV, LT change and baseline vault (under dark condition). In the high-vault subgroup, vault change increased with the increase of CCT, lens displacement and PD change; and increased with the decrease of ACV. Conclusions: ICL vault changes significantly from dark to light, influenced by age, ACV, PD change, LT change, lens displacement, and baseline vault. A higher baseline vault is correlated with a larger LT change, affecting the levels of accommodation under dark-to-light transition.

The main objective of this study is to present a bench marking of the public street lighting in typical road in Morocco. The study deals with a comparison between the conventional technology used in Moroccan road and the LED technology. The simulated system is based on road with two directions and a sidewalk, three arrangements type of pole layout are treated (Left, Middle and Two sides arrangement). Also, in this paper deals with a parametric analysis based on the variation of boom angle, light Center high and the pole distance in order to determine the luminance of each arrangement at each pole distance. The simulation is carried out using two luminaries, the first one represents a conventional technology and LED lamp. The founding of this paper shows that the LED lamp present a high luminance value of 20 cd/m² for a pole distance of 10m and boom angle of 0°, in comparison with the conventional lamp that present a luminance of 8 cd/m² at the same condition. The left arrangement type shows the best energy efficiency indicators such as DE and power per km, this means that this disposition is less consuming of energy and acceptable luminance values. Therefore, these two indicators play a crucial role in enhancing the efficiency of the lighting. [ABSTRACT FROM AUTHOR]

Nowdays screens offer exceptional visuals but it does not work best when displaying some low‐quality images. This paper presents an innovative adaptive scene display technology utilizing neural network to Improve luminance, and optimize display quality. [ABSTRACT FROM AUTHOR]

Copyright of Laser Technology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A high-luminance one-dimensional integral imaging display is presented in this paper. A gradient-width line light source array behind an elemental image array is proposed. The widths of the line light sources with equal pitches gradually increased from both sides to center. The viewing ranges generated by the line light sources were enlarged from both sides to the center. The light illuminating the left half of the elemental image array was superimposed on the right side, and the light illuminating the right half of the elemental image array was superimposed on the left side. The viewing zone was related to the leftmost and rightmost line light sources, and the luminance was improved by enlarging the other line light sources.

Social monogamy is a reproductive strategy characterized by pair living and defense of a common territory. Pair bonding, sometimes displayed by monogamous species, is an affective construct that includes preference for a specific partner, distress upon separation, and the ability of the partner to buffer against stress. Many seahorse species show a monogamous social structure in the wild, but their pair bond has not been well studied. We examined the gene expression of lined seahorses (Hippocampus erectus) during and after the process of pairing in the laboratory as well as color change (luminance), a potential form of social communication and behavioral synchrony between pair mates. When a seahorse of either sex was interacting with its pair mate, their changes in luminance ("brightness") were correlated and larger than when interacting with an opposite-sex stranger. At the conclusion of testing, subjects were euthanized, RNA was extracted from whole brains and analyzed via RNA sequencing. Changes in gene expression in paired males versus those that were unpaired included processes governing metabolic activity, hormones and cilia. Perhaps most interesting is the overlap in gene expression change induced by pairing in both male seahorses and male prairie voles, including components of hormone systems regulating reproduction. Because of our limited sample size, we consider our results and interpretations to be preliminary, and prompts for further exploration. Future studies will expand upon these findings and investigate the neuroendocrine and genetic basis of these behaviors.

In recent years, deep learning techniques had a revolutionary impact on several domains, including computer vision and image processing. This research paper focuses on exploring deep learning methods to achieve precise illuminance estimation, which holds significant importance in applications such as augmented reality, virtual reality, and photography. However, accurately estimating illuminance in complex scenes continues to pose challenges due to the intricate interplay between light sources, objects, and surfaces. The results of extensive experimentation demonstrate the immense potential of deep learning techniques in illuminance estimation. These techniques exhibit promising accuracy and robustness, enabling them to handle diverse scenarios effectively. The valuable insights derived from this study can serve as a guiding framework for future research endeavours and contribute to the development of efficient and precise methodologies for illuminance estimation across a wide range of practical applications. [ABSTRACT FROM AUTHOR]

The human visual cortex processes light and dark stimuli with ON and OFF pathways that are differently modulated by luminance contrast. We have previously demonstrated that ON cortical pathways have higher contrast sensitivity than OFF cortical pathways and the difference increases with luminance range (defined as the maximum minus minimum luminance in the scene). Here, we demonstrate that these ON-OFF cortical differences are already present in the human retina and that retinal responses measured with electroretinography are more affected by reductions in luminance range than cortical responses measured with electroencephalography. Moreover, we show that ON-OFF pathway differences measured with electroretinography become more pronounced in myopia, a visual disorder that elongates the eye and blurs vision at far distance. We find that, as the eye axial length increases across subjects, ON retinal pathways become less responsive, slower in response latency, less sensitive, and less effective and slower at driving pupil constriction. Based on these results, we conclude that myopia is associated with a deficit in ON pathway function that decreases the ability of the retina to process low contrast and regulate retinal illuminance in bright environments. [ABSTRACT FROM AUTHOR]

Purpose: Saturated lights appear brighter than white lights of the same luminance. This is the Helmholtz--Kohlrausch (H--K) effect, and the phenomenon can be estimated by modeling achromatic luminance and saturation to total brightness. Current H--K effect models are different between women and men and are also more variable in women, which may be due to hormonal changes across the menstrual cycle (MC). Methods: Total brightness (B) and achromatic luminance (L) were measured across blue, green, yellow-green, yellow, and red hues. These data were measured along with salivary hormone levels for nine cycling women and seven oral contraceptive (OC) users at points representing the menstrual, peri-ovulation, and luteal phases. Results: Simple brightness/luminance (B/L) ratio estimates of the H--K effect did not differ by OC use or MC phase, but B/L ratios were higher for the red stimulus in cycling women than OC users during the luteal phase. Estrogen, progesterone, and their interaction predicted 18% of the variation in brightness for cycling women. For OC users, only estrogen could be fit to brightness models where it accounted for 5% of brightness variance. Conclusion: These findings first provide clear support for separating cycling women from OC users, particularly when examining long-wavelength mechanisms. Next, the interaction of OC use and MC phase on B/L ratios for the red stimulus adds to a rich history of longwavelength mechanisms. Lastly, the current result amends previous brightness models with multiple hormone terms for cycling women but not OC users. [ABSTRACT FROM AUTHOR]

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Lighting pedestrian crossings play an important role in ensuring the safety of pedestrians on the road, especially at night or in conditions of reduced visibility. Currently functioning normative and formal requirements, which are the basis for the design of lighting for pedestrian crossings, are described by criteria of lighting intensity. Each of the existing solutions operates in an urban environment, and at the stage of design and operation, the obtained values of the produced luminance contrast of the pedestrian silhouette and its background are not known. The main purpose of the article is to compare, based on luminance parameters, the three lighting solutions used at pedestrian crossings. This article presents and describes the method of determining the luminance contrast based on luminance measurements of the pedestrian silhouette and its background. Detailed results of measurements of luminance parameters at selected pedestrian crossings are presented. An analysis of the results was made with a breakdown of typical lighting solutions used in urban conditions. The differences between standard lighting were discussed, as well as supplementary and dedicated lighting. The obtained ranges of luminance contrast levels occurring in urban conditions for individual solutions were determined. The energy indicator for each solution was determined. [ABSTRACT FROM AUTHOR]

Artificial afforestation is especially important for dry steppe regions, where forests perform complex soil-protective, climate-forming, health-improving, and aesthetic functions. Therefore, in 1975–1978, in the Shirinskaya dry steppe of the Republic of Khakassia on the premises of the Sukachev Institute of Forestry, several experimental artificial multispecific plantations of tree and shrub species were created. The studies were carried out in ten biodendrogroups (BDGs) of the Shirinskaya steppe. For comparison, a site of a virgin natural steppe phytocenosis, located in close proximity, was taken. The purpose of these studies was to study the influence of tree and shrub vegetation on the change in edaphic conditions, the ground cover succession, and the change in the soil functioning regime. The maximum positive effect on the biogenic indicators functional activity is exerted by BDGs with edificatory coniferous species, under the crowns of which subordinate shrubs with a sufficient number of leaves develop. Artificial forest plantations contribute to the formation of litter and an increase in the proportion of micromycetes. A correlation was established between abiotic factors, especially illumination, and the growth of terrestrial herbaceous phytomass. Changes in ecological and phytocenotic factors contribute to an increase in biological diversity by optimizing the phytomass reserves and structure and the emergence of new herbaceous vegetation types. Thus, ecologically stable artificial forest biocenoses can form under the dry steppe conditions. [ABSTRACT FROM AUTHOR]

Buildings incorporating kinetic architecture are designed to allow parts of the structure to move without reducing the structural integrity of the building. This is believed to substantially improve both energy efficiency and lighting performance. The aim of this study was to investigate the advantages of employing a kinetic façade system and achieving a comfort illuminance level. A G + 7 office building was chosen as the case study for this research. DIVA-for-Rhino simulation software was used to determine how the proposed kinetic system was integrated and compare it to the baseline case. The results show that kinetic louvers can help to achieve light levels in the range 100–300 lux, and a brightness level of 250 to 350 cd/m2. The total energy used decreased by 21.3% and the Unified Glare Rating (UGR) fell from 29.5 to below 10. In addition, Kinetic louvers achieved 100 – 300 lux and a brightness level of 250 to 350 cd/m2. Furthermore, it was found that an annual reduction of 12% occurred on the east side. More detailed analysis is provided in the paper which will help architects and designers to integrate the kinetic system in the façade of their buildings and achieve visual comfort.

Designing the floodlighting of objects in the context of improving the night image of the city is a very complex task, requiring not only a time commitment but also precise analysis and innovative solutions. In particular, designers must consider the principles of aesthetics and adapt the lighting to the architectural style and details of the facilities while ensuring energy efficiency and minimising the impact on the natural environment. For single objects, the task is relatively simple. The problem arises when the task is to develop a lighting concept for a large ensemble. Computer applications strictly dedicated to lighting analysis cannot capture a 3D model rich in architectural detail. The article presents a case study that focuses on a comprehensive approach to designing the floodlighting of a complex of architectural objects. The steps for designing the floodlighting of objects are presented. Based on a computer simulation, a visual lighting concept and a detailed analysis of the luminance distribution and floodlighting efficiency were presented. The obtained average luminance levels are consistent with recommendations and standards, and the project is characterised by a high lighting efficiency of 56%. This approach enables an understanding of how light affects architectural structures and the surroundings, which is crucial to achieving harmony between the technical side of the project and its aesthetics. The project presented in the article is an inspiring example of how a comprehensive approach to illumination can contribute to creating an attractive night landscape of the city, taking into account the aspects of sustainable development. This is very important nowadays, when the floodlighting of architectural objects is often considered an element of the landscape that can be omitted.

The primary objective of the research and analysis reported in this article was to determine an effective method for predicting the luminance coefficient of the mineral mixture for asphalt concrete and stone mastic asphalt. The luminance of the mineral mixture determines the final luminance value of the surface. Predicting the luminance coefficient quickly will significantly improve the mineral–asphalt mix design efficiency in selecting aggregates that meet functional requirements and increase the brightness of the surface. The research process consisted of two stages. The first stage covered modelling the Qd luminance coefficient of aggregate, taking into account its petrographic analysis. The second fundamental stage, based on the research of the first stage, concerned the modelling of the luminance coefficient of the mineral mixture, taking into account the percentage share of a given component, its grain size, and its photometric properties. An effective technique of reinforced trees was used for modelling. As a result of its application, a model match to experimental data was achieved at the level of 87%. It has also been shown that the greatest impact on increasing the luminance coefficient of the mineral mixture was the use of light aggregate (quartzite sandstone or limestone) with a grain size of 2/5 in quantities > 40% or 8/11 in quantities > 60%. Furthermore, the quartzite sandstone aggregates with a grain size of 5/8 had the highest efficiency in lightening the mineral mixture. However, the use of basalt aggregates of the same fraction significantly worsened the photometric properties of the mineral mixture. An important element of the research was also to indicate that the mineralogical composition of the aggregate is crucial for an accurate assessment of its luminance coefficient.

The article deals with an aspect of the phenomenon of controlled illusion — manipulating emotional reactions and behaviour through the space of an artificially created reality. The subject of the article is a relevant feature of the process — recursion within a fictitious space. The methods of mass suggestion become more complicated with each step of evolution, borrowing the techniques of the past and multiplying them by the technologies of the present. Today’s technologies create a process of self-repetition of elements — a process within a process: artificially created illusions are embodied and massively repeated as patterns. Nowadays, controlled illusion generates a problem of imbalance between the accumulated practice of control and an individual’s ability for distancing. The urgency of the problem is due to the obvious dominance of the methods of manipulating public conscience over the development of an individual via industries of culture. The aim of this article is to define the role of sensory suggestion capabilities through control spaces in the 21st century. The objective is to consider the features of the effects of radiance, the influence of flickering light, and the imitation of the world by adomed structure. These effects stem from the Baroque era, are passed on in evolution, and carry a suggestive potential through an emotional factor. While borrowing and accumulating the techniques of the past, new tools such as artificial intelligence, communication networks, electronics, and biotechnologies bring new qualities to manipulations, including a multisensory impact. The author proposes to reconsider the traditional view on the role of algorithms in cultural objects: what until recently was negatively described as “inanimate” and programmed is now able to control and reveal the emotional potential of a person. The outcome depends on what the algorithms are trained for, who trains them and why. The social function of illusionism is either commercial and political benefit or the promotion of an inclusive culture and the development of a person and their abilities. This cannot but affect the role of designer and artist, whose activity today is increasingly moving away from the decorative and turning to interaction through scientific approaches, which determines the property that offers a choice of path and goal in illusionism.

The energy level offset at inorganic layer–organic layer interfaces and the mismatch of hole/electron mobilities of the individual layers greatly limit the establishment of balanced charge carrier injection inside the emissive layer of halide perovskite light-emitting diodes (PeQLEDs). In contrast with other types of light-emitting devices, namely OLEDs and QLEDs, various techniques such as inserting an electron suppression layer between the emissive and electron transport layer have been employed as a means of establishing charge carrier injection into their respective emissive layers. Hence, in this study, we report the use of a thin layer of Poly(4-vinylpyridine) (PVPy) (an electron suppression material) placed between the emissive and electron transport layer of a halide PeQLEDs fabricated with an inverted configuration. With ZnO as the electron transport material, devices fabricated with a thin PVPy interlayer between the ZnO ETL and CsPbBr3 -based green QDs emissive layer yielded a 4.5-fold increase in the maximum observed luminance and about a 10-fold increase in external quantum efficiency (EQE) when compared to ones fabricated without PVPy. Furthermore, the concentration and coating process conditions of CsPbBr3 QDs were altered to produce various thicknesses and film properties which resulted in improved EQE values for devices fabricated with QDs thin films of lower surface root-mean-square (RMS) values. These results show that inhibiting the excessive injection of electrons and adjusting QDs layer thickness in perovskite-inverted QLEDs is an effective way to improve device luminescence and efficiency, thereby improving the carrier injection balance. [ABSTRACT FROM AUTHOR]

Medical images are commonly used to diagnose and screen various diseases. However, medical images taken by operators with different skill levels have a considerable variation in visual quality. Poor illumination of images increases uncertainty in clinical treatment and lead to the risk of misdiagnosis. This paper proposes a novel bilateral tone‐mapped gamma correction to enhance the visual quality of medical images without affecting the natural color quality. First, the proposed tone‐mapped gamma correction is employed to enhance the intensity values of poorly illuminated medical images. Then, bilateral enhancement curve adjustment is performed to effectively improve the global luminance content of the input image with features and richer information. The image quality assessment measures like entropy, blind/reference less image spatial quality evaluator, natural image quality evaluator, perception‐based image quality evaluator, contrast enhancement based image quality parameter, and color contrast fog density evaluates the superior performance of the proposed technique. The experimental results significantly enhance the intensity difference between dark and bright areas and can aid clinical experts and intelligent health fields. [ABSTRACT FROM AUTHOR]

The quality of indoor lighting significantly influences human well-being, emphasizing the need to integrate lighting planning into the architectural design process. To optimize indoor lighting conditions, light environment simulations are commonly employed. While much of the relevant literature clearly shows that simulations are widely used to predict lighting environments, there is limited active research validating these simulations. Therefore, this study aimed to assess the alignment between actual measurements and simulations, specifically focusing on daylight-induced glare. To achieve this, a comparative analysis and verification of glare levels between simulations and actual measurements were conducted that accounted for glare location and direction. Disparities between the simulated and measured glare levels were revealed contingent on the glare location and direction. These variations primarily arose from the simulation's utilization of a fisheye field of view (FOV) for glare measurement. To improve the accuracy of glare analysis in simulations, it is advisable to follow the standards related to the human perception of glare, such as the human field of view (FOV), instead of solely depending on a fisheye FOV. The study's limitations include challenges in environmental replication, minor measurement errors, and tree branch shading interference. Despite the potential for simulations to not replicate temporary glare effects, consistent differences with actual measurements indicate that the fisheye FOV was a key contributing factor. [ABSTRACT FROM AUTHOR]

Fundus disorders like Glaucoma are a serious health risk that affects people all over the world, lowering their quality of life. Optic disc (OD) segmentation is a crucial step for automatic detection of glaucoma with fundus images. This paper presents an efficient and accurate OD segmentation methodology from eye fundus images. In the proposed methodology, fundus images are transformed from RGB (Red, Green, and Blue) color space to LAB (Luminance, A‐axis, B‐axis) color space. A new image is generated using the luminance, A‐axis component, and image information content. As a pre‐segmentation stage, the unsupervised approach extracts the region of interest containing OD. The adaptive threshold method, followed by morphological operations, extracts the contours of the OD region and removes the spur. Segmentation of OD is a challenging task due to similar intensity levels with neighborhood, vascular occlusion, and retinal atrophy. The proposed work overcomes the challenges by segmentation of the OD at three levels, which enhances the functionality at different illumination conditions. The features are extracted at various levels to determine whether the segmented image contains the OD or not. The efficiency of the proposed methodology demonstrates by applying it to a variety of fundus images from datasets, namely ISBI IDRiD, DRISHTI‐GS, and SYSU. Key performance metrics like Intersection over Union and Dice Coefficient are used to evaluate the performance of the proposed methodology. The proposed methodology achieves Intersection over Union of 0.996, 0.997, and 0.994 on ISBI IDRiD, DRISHTI‐GS, and SYSU datasets, respectively. Similarly, the proposed methodology obtains 0.96, 0.97, and 0.98 Dice Coefficient on the three datasets. [ABSTRACT FROM AUTHOR]

This article focuses on the issue of portable traffic signs and their visibility using different light sources such as halogen, Xenon, or LED. The measured values of luminance and retroreflection for each object are used to distinguish the individual results. The results show the differences between the various light sources on the visibility of the measured objects. Furthermore, from these results it is possible to evaluate portable traffic signs regarding degradation due to mechanical wear or aging.

Demand planning-oriented research on nighttime urban lighting provides a foundation for formulating strategies to eliminate dark areas and reduce light pollution. In this paper, Binjiang District of Hangzhou was investigated. Four factors, namely land-use type, road grade, parcel volume, and nighttime crowds, were evaluated. Based on the spatiotemporal geographic data and the urban lighting planning of Hangzhou, a calculation method for the supply and demand of urban lighting at night in Hangzhou was constructed. In this process, the current state of lighting brightness in different areas of the district were calculated and compared with the results of the total lighting demand to analyze reasonableness. The research results show that according to the actual lighting demand classification, the first to fifth levels of lighting control zones accounted for 1.84%, 19.69%, 49.61%, 21.74%, and 7.12% of the total statistical land area of the district, respectively. Focus should thus be placed on the second, third, and fourth levels of lighting control zones when covering lighting demand. Importantly, areas with unreasonable supply and demand for lighting construction accounted for 20.8% of the total statistical land area, indicating that the nighttime lighting demand and carbon emissions in the Riverside District should be adjusted and optimized. This paper proposes a research method to compare supply and demand for the planning and construction of nighttime urban lighting, which can improve the science on lighting demand measurement. [ABSTRACT FROM AUTHOR]

Objectives: Photochromic contact lenses (PCL) are designed to increase the comfort of patients, in bright light conditions. The aim of the study was to evaluate the effect of PCL on pupil size. Methods: The study was conducted with 30 patients who were admitted to the contact lens department. Automated pupilography images of the right eyes of patients were obtained without contact lenses (group 1) in scotopic (S: 0.4 lux), mesopic (M: 4.0 lux), and photopic (p=40 lux) conditions. The procedures were repeated with silicone hydrogel contact lenses (Group 2) and with silicon hydrogel PCL (group 3). Results: Mean age was 23.87±3.27 (17-30) years and male/female ratio was 10/20. The mean spheric equivalent of their right eyes was -3.60±1.73 (-0.50--7.50). Pupil diameters of Group 3, under scotopic conditions, were larger than Group 1 and 2 (p=0.001, p=0.044). There was no difference between groups under mesotopic and photopic conditions. Pupil diameters at the different illumination levels were similar regarding gender. Conclusion: Similarity in mesotopic and photopic pupil sizes compared to all groups may be a result of insignificant pupil changes of photochromic lenses in indoor conditions or insufficient time for lens activation. [ABSTRACT FROM AUTHOR]

Sustainable road lighting aims to minimize energy consumption and reduce carbon emissions. Road lighting assessment helps evaluate the energy efficiency of lighting systems, including the selection of appropriate lighting fixtures, efficient lamp technologies (such as LED), and lighting control strategies. Assessments can identify areas for improvement and guide the implementation of energy-saving measures. This study introduces a new technology that utilizes a specially equipped vehicle to efficiently and quickly measure photometric quantities on long, illuminated roads. The measurement ranges for illuminance and luminance are (0.1 to 1000) lx and (0.1 to 100) cd/m2, respectively. The equipped vehicle has a positioning resolution of less than 1 cm. A sampling distance of less than 2 m while traveling at a speed of approximately 20 km/h and a sampling rate of 3 samples/s. To test the system's applicability, the road used in this study was slightly sloped and curved. The results indicate a strong correlation between the illuminance distributions measured by the new method and those measured by traditional methods, thereby confirming the effectiveness of this innovative approach. [ABSTRACT FROM AUTHOR]