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Reflectivity of Various Surfaces / Materials |
The amount of light that is returned from a target's surface is characterised by the reflection coefficient r. For a diffusely reflecting target, the maximum value of r is 100 %. For mirror-like or retroreflecting targets, the (theoretical) value of reflectivity can exceed 100 % by far. The reflection coefficient is, of course, depending on the wavelength also.
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Diffuse reflection:The signal is reflected omni-directionally according to Lambert's cosine law |
Mirror-like reflection:The angle of the reflected beam with respect to the targets surface is equal to the angle of incidence. Incident beam and reflected beam lie in the same plane. |
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Retroreflection:The retroreflected beam is returned in the same direction from which the incident beam came. This property is maintained over a wide range of directions of the incident beam. |
MATERIAL |
REFLECTIVITY |
| White paper | up to 100% |
| Dimension lumber (pine, clean, dry) | 94% |
| Snow | 80-90% |
| Beer foam | 88% |
| White masonry | 85% |
| Limestone, clay | up to 75% |
| Newspaper with print | 69% |
| Tissue paper, two ply | 60% |
| Deciduous trees | typ. 60% |
| Coniferous trees | typ. 30% |
| Carbonate sand (dry) | 57% |
| Carbonate sand (wet) | 41% |
| Beach sands, bare areas in dessert | typ. 50% |
| Rough wood pallet (clean) | 25% |
| Concrete, smooth | 24% |
| Asphalt with pebbles | 17% |
| Lava | 8% |
| Black neoprene | 5% |
| Black rubber tire wall | 2% |
MATERIAL |
REFLECTIVITY |
| Reflecting foil 3M2000X | 1250% |
| Opaque white plastic 2) | 110% |
| Opaque black plastic 2) | 17% |
| Clear plastic 2) | 50% |
Note:
1) Values of reflectivity given
for a wavelength of about 0.9 micrometers
2) For materials with shiny or glossy surfaces, the reflectivity
figure represents the maximum light return, with the sensor beam exactly perpendicular
to the material surface.
Information contained herein is believed to be accurate and reliable. However, no responsibility is assumed by RIEGL for its use. Technical data are subject to change without notice.
RIEGL General Information GI004 (10/94)
Back to Principle of a Pulsed Laser Sensor
Last updated 05/23/02
