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New tool constructions for polishing surface of granite facing tool program in construction
Published in Evgeny Rybnov, Pavel Akimov, Merab Khalvashi, Eghiazar Vardanyan, Contemporary Problems of Architecture and Construction, 2021
P. Rajczyk, K. Bednarczyk, S. Evtyukov
In order to determine the quality of surface polishing, it is advisable to develop a methodology for measuring the degree, including the classification of surface polishing, using gloss meters. These devices are designed to measure the amount of light reflected. The principle of operation of the gloss meter is based on the fact that the device emits a beam of white, non-polarized light at a specific angle measured between the straight line parallel to the light beam and the perpendicular to the tested surface. There are devices with a geometry of 20°, 45°, 60°, 75°, 85°. The geometry in this case is the angle of light emission measured on the test surface. The light beam is reflected from the measured surface and enters the measuring device, which measures its intensity; the smaller the difference between the emitted and reflected light intensity (with the same geometry), the greater the gloss. The result of the measurement is a part (given in%) of the amount of light emitted (i.e. 100%) by the gloss meter. Often the percentage (%) is converted into points (points) for simplicity. In order to obtain the correct measurement results, the following rule is applied: for high gloss, low measurement geometry (20° angle) is used, and for low-gloss, matt surfaces, high geometry (85° angle). The basic standards for measuring gloss are defined in the following standards: ASTM D 2457, DIN EN ISO 2813 and DIN 67530.
Polymer/Filler Composites for Optical Diffuse Reflectors
Published in Mahmood Aliofkhazraei, Advances in Nanostructured Composites, 2019
A good understanding of the theories for optical applications is a prerequisite for designing and optimizing polymer-filler nanocomposite reflectors. It is known that the interaction of light with a material includes scattering (reflection and absorption) and transmission of the incident light. Figure 2 presents a simplified schematic diagram of the interaction of an incident light with polymer-filler composites. The polymer-filler composite reflector is treated as spherical fillers of certain radius homogeneously dispersed within the weak-absorbing polymer matrix. When a beam of light strikes on such a material, it is partially scattered from the surface and partially transmitted into the material. The relative fraction of specular reflection and diffuse reflection determines the visual appearance of a bulk material. Usually, the surface of a material looks glossy if specular reflected light is predominated, while it will be matt if the surface-scattered light is the major component. The ceramic fillers (TiO2, SiO2, Al2O3, ZnO, etc.) are strong scattering and non-absorbing in the wavelength of visible light, and the composite reflectors have a largely diffuse appearance. The key factors affecting the reflectance of composites are particle size of fillers, difference of refractive indices between fillers and matrices, and thickness of reflectors (Berger et al. 2007).
An Introduction To Light
Published in Craig DiLouie, Lighting Redesign for Existing Buildings, 2020
Task and adjacent surface reflectance, expressed as a percentage of light reflected versus absorbed, is also important. The reflectance of the task and its surround should enable resulting luminance to be within recommended luminance ratios. Walls, ceilings and objects in the space, meanwhile, should have a high reflectance to produce desirable interreflections and improve average light levels and visual comfort. Reflectance should not be confused with glossiness (specularity); glossy surfaces may appear brighter to the eye, but that brightness is more likely to produce unwanted glare. For walls and ceilings, light-color matte finishes are often desirable.
A Review of Illuminance Mapping Practices from HDR Images and Suggestions for Exterior Measurements
Published in LEUKOS, 2023
Arpan Guha, Alayne Nyboer, Dale K. Tiller
The sensation of vision and color is caused by light interacting with objects around us. For example, an apple appears red because it predominantly reflects the wavelengths corresponding to the “red” region of the visible spectrum, while absorbing all others. Thus, the behavior or pattern of reflected or transmitted light is dependent on how it interacts with the materiality of the respective surfaces. To characterize this a surface property, reflectance (ρ), is used. Reflectance is the ratio of the luminous flux reflected by a surface to the incident luminous flux. For example, a surface having a reflectance of 0.8 reflects 80% of the incident luminous flux. Reflection patterns can be categorized into two types: specular and diffuse reflection. In surfaces exhibiting specular reflectance the incident light rays are reflected at the same angle; essentially mirror-like characteristics (e.g. glossy surfaces, reflective liquids, etc.). On the other hand, if light strikes a surface and is scattered evenly across all directions, the surface is said to be matte or exhibit diffuse reflectance (e.g. carpets, clothes, paper, etc.). Figure 4 illustrates specular and diffuse reflections. First (or front) surface mirrors approximate perfect specular reflection.
Finishing performance of Acacia mangium wood surface-treated with methanol
Published in The Journal of Adhesion, 2022
Redzuan Mohammad Suffian James, Paridah Md Tahir, Lee Seng Hua, Ummi Hani Abdullah, Mohd Khairun Anwar Uyup, Norwahyuni Mohd Yusof, Izwan Johari
Gloss is the measurement of the reflectance of the specular light of the coated surface. In gloss measurement tests, beam light is directed towards the coated surface at certain perpendicular angles. The percentage of the beam which is reflected at the same angle is measured by the photocell. Generally, the wood industry uses the 60° angle of reflection. Other commonly used measurement angles are 20° and 85°. The 20° angle of measurement can be used when measuring gloss units above 70°; the 85° angle is used when measuring gloss below 10°. The classification of lacquers according to gloss ratings depends on the ability of the surface to bounce back a varying amount of light beamed on it, and these readings show the relative reflectivity of the coated surface compared to the smooth, flat mirror.[11]
Multi-criteria decision-making methodology for the selection of cargo hold coating for bulk carriers
Published in Ships and Offshore Structures, 2019
Ioannis Arabatzis, Ioannis Skordas, Dimitrios Skordas, Lampros Nikolopoulos, Petros Kousiounelos, Evangelos Boulougouris
Gloss is the attribute of surfaces that causes them to have shiny or lustrous, metallic or matte appearances (Marrion 2017). It is attributed to the reflection of the incident light. A gloss metre is an instrument, which is used to measure specular reflection gloss of a surface. Gloss is determined by projecting a beam of light at a fixed intensity and angle onto a surface and measuring the amount of reflected light at an equal but opposite angle. For this study, GL0030 TQC PolyGloss 60o/20o/85o gloss metre was used. The incident light beam was set at 60o.