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applications require coatings that reflect large amount of the
incident light or a specific amount. These are high reflection or
partial reflection coatings. These can be either metal coated or
dielectric coated. |
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Metal
Coatings |
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Coating of metals like aluminum / silver / gold
on the polished glass surface increases the reflection and are useful
for many applications. These metals characteristically exhibit high
reflection over very broad wavelength regions. |
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Aluminum coated mirrors are very stable and most
commonly used since aluminum gives reflection right from UV to IR
region. Aluminum mirrors to be used in the visible region are usually
protected with a layer of Silicon Monoxide for durability. To increase
the efficiency of the coating and to make it even more durable,
enhanced aluminum mirrors are available for visible region which have
multiple dielectric layers on top of the aluminum to boost the
reflection. UV aluminum mirrors are those which have high reflection
even in the UV region, unlike protected mirrors. These are useful for
spectrometers and in other instruments. |
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Reflection of bare
aluminium |
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Reflection of protected aluminium |
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| Reflection of Enhanced aluminium |
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Reflection of UV aluminium |
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Reflection of Silver |
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has the highest
reflection in the visible region but is more expensive due to the
difficulties involved in the coating process. The coatings are not as
stable as aluminum. We give protected silver coatings which are as
durable as aluminium coatings. |
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Reflection of Gold |
| Gold coatings
can be used for reflection in IR region. We provide protected gold
coatings also. |
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Dielectric high reflection coatings |
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Dielectric coatings are used when higher
reflectionand durability is required as compared to metal coatings. These can
be tuned for wavelengths from UV to IR region and for specific angle of incidence. |
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| Reflector
for 266nm , 45° incidence, mean polarization |
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Reflector
for 500 - 600nm , 0° incidence |
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| Reflector for 700 - 900nm ,
0° incidence |
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Dielectric partial reflection Coatings |
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Dielectric coatings can also be tuned to get partial
reflection. These are normally used at
normal incidence. These may have an anti-reflection coating on the opposide side. |
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| Partial
Reflector for 400-700nm, Average 25%R |
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Partial
Reflector for 500-800nm,
50%R |
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Partial
Reflector for 1064nm,
20%R |
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Partial
Reflector for 1064nm,
60%R |
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