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清凉的灯;天外来灯;善变的灯;七窍玲珑灯     

汽车前照灯灯体变形控制方法

为了减少汽车前照灯灯体在使用中遇到的后变形情况,满足用户的需要,分析了灯体变形形式和变形产生的原因,对生产现场提出了控制灯体变形的几种方法或处理形式,较好地解决了汽车灯具的灯体后变形的问题。经过生产实践,灯体变形得到较好的控制,灯体变形报废率仅为3%,得到了用户的认同。     

荧光灯制灯工艺对卤粉性能影响的研究

制作荧光灯时,灯用卤粉先后经过球磨、烤管、排气(或释汞)、老炼等工艺程序。这些工艺对卤粉发光性能的影响,主要在球磨、烤管工艺对卤粉发光性能的影响作过研究和报导。我国各制灯厂的制灯工艺尚未建立起严格的统一规范,因而同一性能的灯用卤粉在不同制灯厂的制灯水平差异较大,为此有必要就制灯工艺对卤粉发光性能的影响开展系统工作,以搞清不同制灯工艺对卤粉性能的影响并分析其原因,从而为改进卤粉应用特性和为消除不合理的制灯工艺对卤粉带来的有害影响,进而为提高荧光灯的光学性能提供有效的实验数据,对于提高灯的性能有着重要的经济价值。     

谈绿色照明在玻璃厂的应用

LED灯已经广泛应用于工业中。本文主要讲述了LED灯在玻璃厂的应用和LED灯与传统灯具比较更加突出的一些优势。     

New Gear新品

最新数码摄影器材点评和打分!TRINITY影棚灯套装〉WWW.STUDIO-FLASH.COMTrinity影棚套装易于使用、功能强大的影棚灯套装,非常适合外拍。影棚灯可能不是每个摄影爱好者必备的产品,但是如果你接触过这款Trinity影棚灯套装,你就会知道它有多么实用。这款影棚灯套装制作工艺精良,而且外形也很时尚。它的使用方法简单,操作界面直观,可以快速调节输出功率。这款影棚灯便于携带,非常适合经常外拍的摄影师。     

752型紫外分光光度计光源灯的更换与调校

７５２型紫外分光光度计的光源灯有氢灯、钨灯两种，它们的位置变动将引起波长示值误差。因此，光源灯的更换与波长调校是仪器维修及分析工作者的一项繁杂的工作。根据我们的实践，具体操作可分为三步进行。１氢灯的更换与调整更换氢灯时应关掉氢灯电源，将波长选择在紫外...     

有关紫外灯的问与答

1.问:什么是紫外灯? 答:紫外灯也是一种荧光灯.在宝石鉴定中常用的是长波紫外灯和短波紫外灯.长波紫外灯又称为黑光灯,(辐射UV-A)其主要发光波长为365nm的长波光线,短波紫外灯(辐射UV-)其主要发光波长为253.7nm的短波光线,都具有辐射频率高,光子能量大的特点.     

某灯具LED灯珠封装胶体失效分析

针对某发光二极管（LED）灯具在老化过程中,灯珠封装胶体的变色甚至脱落问题,开展失效分析。通过LED灯珠切片分析、X射线透视、红外光谱分析、红外热像分析、有限元分析等技术手段,并设计相关验证试验分析灯珠封装胶体失效的原因。结果表明,灯珠封装胶体靠近芯片和灯珠外表面变色严重;灯珠内部结构一致,均串联连接;失效和正常灯珠封装胶体均为有机硅树脂材料,灯具整体散热性能对灯珠失效没有影响;有限元分析和模拟验证表明封装有机硅树脂材料的失效是LED芯片热量和腔体内积聚热量双重作用的结果;建议将灯具支撑柱进行开孔或直接制成网状结构,以让反射罩和支撑柱之间阻隔散热的静止空气流动起来,然后再根据实际情况进行优化。     

金鸡岩选煤厂胶带输送机走廊照明系统节能改造

介绍了金鸡岩选煤厂胶带输送机走廊照明系统存在的不足,分析了新一代电磁感应灯和LED灯的技术特点及优越性;应用新型灯对选煤厂胶带输送机走廊照明系统进行了改造,取得了很好的经济效益。     

几种因素对新型环保油性灯片使用质量的影响

针对新型环保的油性灯箱灯片,进行耐用性能测试,包括温度测试、湿度测试、紫外线老化测试、模拟雨水冲刷性能的测试。利用试验结果,分析了四种因素对灯片使用寿命和使用质量的影响,并提出较为合理的使用建议。结果表明,四种因素对环保灯片使用质量影响的大小顺序为：温度〉紫外线循环次数〉湿度〉雨水冲刷频率;且使用普通灯管会使灯片产生紫外老化和热老化现象,而使用LED冷光灯可有效地避免紫外老化和热老化现象,提高灯片的使用质量和使用寿命。     

Evaluation of discomfort glare from color leds and its correlation with individual variations in brightness sensitivity

The light‐emitting diode (LED) has attracted attention as an alternative light source to fluorescent and incandescent lighting. The characteristics of LED light are different from other sources, but regulations for LED products have not been completely established. Common LED lights, such as automotive lamps, street lighting systems and traffic lights, are produced under the existing glare regulations for other light sources, and some organizations are seeking to establish standardized regulations for LED products. Glare can impair vision and cause discomfort and must be considered when establishing regulations for lights. In this study, we measured the sensitivity of observers to the discomfort glare from color LEDs and analyzed the correlation between discomfort glare sensitivity and brightness sensitivity using heterochromatic brightness matching and flicker photometry. The results indicate a correlation between discomfort glare sensitivity and brightness sensitivity using blue LEDs and mild correlations with green and red LEDs. © 2010 Wiley Periodicals, Inc. Col Res Appl, 2010.     

基于单片机的LED线阵显示装置的研究

采用STM32F103系列STM32F103RET6两片单片机作为核心器件,通过红外数据接收器接收录入的图文信息,利用高精度算法优化,采用16个共阴极红绿双色LED灯显示图形,设计并制作了一个LED线阵示装置。通过电机带动LED线阵高速旋转,由于人眼的视觉暂留现象,看到的显示内容效果跟平面连续显示效果一样。通过多次测试,LED线阵显示效果均达到预期要求。     

Evaluation of the visibility of colored objects under led lighting with various correlated color temperatures

This study proposes a “visibility” concept of colored objects that includes a combination of color brightness and appearance perception of colored objects that are illuminated by seven LED lights (each with a CIE color rendering index under 80 but with various correlated color temperatures). To determine the brightness perception of colored objects, luminance calculations and measurements were conducted. The areas of the “color brightness graph” in this study correspond to the results of eight different color sample papers under each of the LED lights with different CCTs. The luminance values were calculated by multiplying the SPD by the spectral luminous efficiency and spectral reflectance of a colored object. The luminance values were measured under these conditions to identify the relationship between the luminance calculations and the measured values. Efficient CCTs were identified for each color sample in terms of the brightness of the colored object. Further subjective evaluations were also conducted to identify the relationship between luminance values and subjective brightness perception. In addition, subjective evaluations of the color appearance perception were conducted to identify the overall visibility concept of colored objects. The subjective evaluations included brightness perception, color appearance, and similarity of the reference light source. The visibility of the colored objects was analyzed according to the results of the brightness and appearance perception of the colored objects that were illuminated by LED lights with various CCTs. © 2016 Wiley Periodicals, Inc. Col Res Appl, 42, 78–88, 2017     

Colour matching experiments with RGB‐LEDs

CIE colorimetry breaks down when lights produced by narrow band RGB‐LEDs are matched with broad‐band lights. A colour matching experiment was set up and matches in a number of parts of the chromaticity diagram have been made, to determine the magnitude of the discrepancy. Differences between visual and instrumental matches increase as one moves in the chromaticity diagram from yellowish white lights toward greenish and bluish lights. CIE TC 1‐36 recently suggested newly defined cone fundamentals: Applying a transformation of these to a space similar to the CIE XYZ space enables a much better prediction of the matches to be made. The difference between the visual match and its instrumental prediction decreases by a factor of two or even more. The use of a cone fundamental based colorimetric system is recommended for LED colorimetry. © 2008 Wiley Periodicals, Inc. Col Res Appl, 33, 108–112, 2008     

Effect of color temperature on appearance of paintings exhibited under LED lighting

Colour of light modulates the appearance of displayed artifacts in exhibition. To understand the effect of light on appearance of paintings, few studies have experimented to establish a relation between pleasantness with the correlated colour temperature (CCT) of light. However, some studies have found that CCT has no significant effect on pleasant appearance of painting. Therefore, in this article, an experiment with a qualitative (questionnaire on semantic differential scale, N = 30) approach was designed to understand the effect of CCT on appearance of paintings exhibited under LED lights. The findings from the experimental result depict that the appearance of paintings changes due to different CCTs of LEDs having the same illuminance. In addition, the result reveals that for both mediums of paintings considered in this study, in comparison to warm white LED and artificial daylight LED, cool white LED has appeared to be more pleasant having moderately warm feelings to the viewers.     

Testing LED lighting for colour discrimination and colour rendering

Light‐emitting diode (LED) technology offers the possibility of obtaining white light, despite narrow‐band spectra. In order to characterize the colour discrimination efficiency of various LED clusters, we designed a classification test, composed of 32 caps equally distributed along the hue circle at about 3 ΔE* _ab‐unit intervals. Forty normal colour observers were screened under four different LED test light sources adjusted for best colour rendering, and under one control incandescent light of the same colour temperature. We used commercially available red, green, blue, and/or amber LED clusters. These yielded a poor colour rendering index (CRI). They also induced a significantly higher number of erroneous arrangements than did the control light. Errors are located around greenish‐blue and purplish‐red shades, parallel to the yellow‐axis direction, whereas when the distribution of light covers the full spectrum, the LED clusters achieve satisfactory colour discrimination efficiency. With respect to the lights we tested, the colour discrimination is correlated with the CIE CRIs as well as with a CRI based on our sample colours. We stress the fact that increasing the chroma of samples by lighting does not necessarily imply an improvement of colour discrimination. © 2008 Wiley Periodicals, Inc. Col Res Appl, 34, 8–17, 2009.     

Light wavelengths of LEDs to improve the color discrimination in Ishihara test and Farnsworth Panel D‐15 test for deutans

This study was performed to determine significant light wavelengths to improve color discrimination ability of subjects with deutan. We conducted both the Ishihara test and the Farnsworth Panel D‐15 test for subjects with deutan and normal color vision. Seven different LED lights from 450 to 660 nm and an additional D65 white lamp were utilized to change the lighting conditions, including the wavelength and intensity. The results of the Ishihara test and D‐15 test showed that color identification of deutans was markedly improved with the longer wavelength LEDs regardless of the intensity of the additional D65 lamp. Notably, the error rates of deutans in the Ishihara test were <25% for LED wavelengths of 630 and 660 nm. In the case of subjects with normal color vision, the D65 lamp abolished the errors in the Ishihara test, regardless of the LED wavelength. Addition of the D65 lamp also decreased the number of crossings in the D‐15 test. These results suggested that illumination by LED light with longer wavelengths, such as 630 and 660 nm, may provide deutans with greater red‐green discrimination ability in both the Ishihara test and the Farnsworth Panel D‐15 test. © 2016 Wiley Periodicals, Inc. Col Res Appl, 42, 424–430, 2017     

The effect of curing lights and modes on dentin bond strength of bulk-fill composites applied in different thickness

To investigate shear bond strength (SBS) to dentin of a conventional and three bulk-fill composites applied in different increment thickness and cured by mono- and multi-wave LED LCUs. Two hundred and fifty-two extracted sound human molars were prepared for SBS test. The teeth were divided into four groups according to the resin composites used. Conventional composite: Tetric N-Ceram (control); high-viscosity bulk-fills: Tetric N-Ceram Bulk Fill, X-tra Fil, and SonicFill. Each group was subdivided (n?=?7) according to increment thickness (2, 4, and 6?mm) and cured by standard mode of a mono-wave LED or two different modes (standard and xtra power) of a multi-wave LED. The failure mode was stereomicroscopically determined at 40× magnification. Data were analyzed using Three-way ANOVA and further comparisons were assessed by Bonferroni’s multiple comparison test. There were no significant differences within X-tra fil and Tetric N-Ceram Bulk Fill groups for any of the variables (p?>?0.05). A significant decrease in SBS values with increase of layer thickness was observed for SonicFill and control groups. Also, curing mode had a significant effect on both composites at 6?mm thickness and standard mode of multi-wave LED caused the highest SBS value (p???0.05). Adhesive failure was the most common fracture pattern especially at 6?mm thickness applications. Based on the results of this study, the bulk-fill composites can be safely applied in one-step with 4?mm increments, although the examined composites performed better at 2?mm thickness. The performance of the composites at 6?mm increment may show differences related to the curing lights and modes.     

The Protective Function and Modification of Secondary Metabolite Accumulation in Response to Light Stress in Dracocephalum forrestii Shoots

The aim of this work was to determine the effect of stress conditions caused by different light sources, i.e., blue LED (λ = 430 nm), red LED (λ = 670 nm), blue and red LED (70%:30%) and white LED (430–670 nm) on the growth and morphology of cultivated in vitro Dracocephalum forrestii shoot culture. It also examines the effects on bioactive phenolic compound production and photosynthetic pigment content, as well as on antioxidant enzyme activity (CAT, SOD, POD) and antioxidant properties. The most beneficial proliferation effect was observed under white LEDs (7.1 ± 2.1 shoots per explant). The white and blue lights stimulated the highest fresh weight gain, while red light induced the highest dry weight gain. The total phenolic acid content ranged from 13.824 ± 1.181 to 20.018 ± 801 mg g DW⁻¹ depending on light conditions. The highest content of rosmarinic acid was found in the control shoots (cultivated under fluorescent lamps), followed by culture grown under red light. All LED treatments, especially red and blue, increased salvianolic acid B content, and blue increased apigenin p-coumarylrhamnoside biosynthesis. The greatest ferric reduction activity was observed in shoots cultivated under red light, followed by blue; this is associated with the presence of the highest total phenol content, especially phenolic acids. Similarly, the highest DPPH radical scavenging potential was observed under red light followed by blue. This study proves that LEDs have emerged as significant support for directed in vitro propagation, taking advantage of specific stress responses on various light spectra. This study also showed how stress induced by different LED light spectra increases in Dracocephalum forrestii the synthesis of pharmacologically-active compounds. Hence, light stress may turn out to be a simpler alternative to metabolic engineering for improving the production of secondary metabolites of therapeutic value.