Thermal Imager Camera
Maintenance
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8. Maintenance
8.1. Cleaning the Lens
Keep the lens clean at all times. Any foreign matter (dust, fingerprints…) on the lens or window
surface will affect measurement accuracy. However, care should be taken when cleaning the
lens.
To clean the window, do the following:
1. Lightly blow off loose particles with “canned” air (used for cleaning computer
equipment) or a small squeeze bellows (used for cleaning camera lenses).
2. Gently brush off any remaining particles with a soft camel hairbrush or a soft lens tissue
(available from camera supply stores).
3. Clean remaining “dirt” using a cotton swab or soft lens tissue dampened in distilled
water. Do not scratch the surface.
For fingerprints or other grease, use any of the following:
•
Denatured alcohol
•
Ethanol
Apply one of the above to the lens. Wipe gently with a soft, clean cloth until you see colors on
the surface, then allow to air dry. Do not wipe the surface dry, this may scratch the surface.
If silicones (used in hand creams) get on the window, gently wipe the surface with Hexane.
Allow to air dry.
Do not use any ammonia or any cleaners containing ammonia to clean the
lens. This may result in permanent damage to the lens’ surface!
9. Addendum
9.1. Typical Emissivity Values
The following table provides a brief reference guide for determining emissivity and can be used
when one of the above methods is not practical. Emissivity values shown in the table are only
approximate, since several parameters may affect the emissivity of a material. These include
the following:
1. Temperature
2. Angle of measurement
3. Geometry (plane, concave, convex)
4. Thickness
5. Surface quality (polished, rough, oxidized, sandblasted)
6. Spectral range of measurement
7. Transmissivity (e.g. thin films plastics)
