China
Africa
Explore chapters and articles related to this topic
Luminous Environment Design Strategies
Published in Chitrarekha Kabre, Synergistic Design of Sustainable Built Environments, 2020
Specular reflection happens when parallel rays of incident light remain parallel after reflection from a surface; the surface is a ‘plane mirror.’ The rules of geometrical optics apply to such surfaces: the angle between the reflected ray and the normal to the surface will equal the angle between the incident ray and the normal; from a convex mirror the reflected rays will be divergent, and from a concave mirror they will be convergent. Spread reflection spreads parallel rays into a cone of reflected rays. Diffuse reflection reflects the light at many angles. In diffuse reflection each ray falling on an infinitesimal particle obeys the law of reflection, but as the surfaces of the particle are in different planes, they reflect the light at many angles. Most common materials are compound reflectors and exhibit all three reflection components (specular, spread, and diffuse) to varying degrees (Figure 4.8).
Sample Handling in Infrared Spectroscopy — An Overview
Published in Patricia B. Coleman, Practical Sampling Techniques for INFRARED ANALYSIS, 2020
Diffuse reflection is, by definition, that process in which the angle of reflection is different from the angle of incidence. In the visible- and near-infrared regions of the spectrum, diffuse reflectance measurements have been made for many years using integrating spheres. There have been some attempts to use these devices in the mid-infrared, but the very low levels of reflectivity and the energy limitations of dispersive instrumentation have combined to make the technique unattractive.
Principles and Applications of UV Light Technology
Published in Tatiana Koutchma, Ultraviolet Light in Food Technology, 2019
Reflection is the change in the direction of propagation experienced by light deflected by an interface. Reflection may be classified as specular or diffuse. Specular reflection occurs from smooth polished surfaces where the roughness of the surface is smaller than the wavelength of light. Diffuse reflection occurs from rough surfaces where light is scattered in all directions with little dependence on the incidence angle.
Morphological Box Classification Framework for supporting 3D scanner selection
Published in Virtual and Physical Prototyping, 2018
W. L. K. Nguyen, A. Aprilia, A. Khairyanto, W. C. Pang, G. G. L. Seet, S. B. Tor
When an optical wave reflects off any surface, there are two forms of reflection, which are specular and diffuse reflection. Specular reflection is the mirror-like reflection of waves, where the incident ray and reflected ray have the same angle to the surface normal. Diffuse reflection is the reflection of waves in many directions, or angles, due to the scattering of the waves. When scanning a typical surface, the receiver usually captures a reflected wave reflected by diffuse reflection, as the receiver is seldom at the same angle away from the surface normal as the optical source. However, in the case of a reflective surface, the specular reflection is the dominant form of reflection, with little diffuse reflection (Figure 1(e)). This leads to little or no reflected energy captured by the receiver, and cause the same problem as black or dark-coloured surfaces.
In vivo assessment of gloss from surfaces of complex shapes: the particular case of the human tooth
Published in Transactions of the IMF, 2018
S. S. Chitko, J. S. Kulkarni, A. S. Kulkarni, R.B. Kuril
However, in clinical or household conditions flattening of the tooth is not possible. Also in dental as well as in many other industrial applications completely flat surfaces are rarely encountered. Most surfaces are uneven and have a complex geometry. Therefore, the standard practice of comparing the gloss of such a surface with a flat one has limitations and is likely to be misinterpreted. Also, the human eye sees the surface as a whole, and not as the specular reflection only. Diffuse reflection is the reflection seen from an irregular surface (Figure 1(b)). In diffuse reflection, similar light intensities are seen at various angles as compared to the incident light. The complex wave fronts generated by diffuse reflection are thus of more importance for measuring gloss.