Product Manual
Table Of Contents
- 1 Disclaimers
- 2 Safety information
- 3 Notice to user
- 4 Customer help
- 5 Quick Start Guide
- 6 Description
- 7 Operation
- 7.1 Charging the battery
- 7.2 Turning on and turning off the camera
- 7.3 Saving an image
- 7.4 Recalling an image
- 7.5 Deleting an image
- 7.6 Deleting all images
- 7.7 Measuring a temperature using a spotmeter
- 7.8 Measuring the hottest temperature within an area
- 7.9 Measuring the coldest temperature within an area
- 7.10 Hiding measurement tools
- 7.11 Changing the color palette
- 7.12 Changing image mode
- 7.13 Changing the temperature scale mode
- 7.14 Setting the emissivity as a surface property
- 7.15 Setting the emissivity as a custom material
- 7.16 Changing the emissivity as a custom value
- 7.17 Changing the reflected apparent temperature
- 7.18 Changing the settings
- 7.19 Updating the camera
- 8 Technical data
- 9 Declaration of conformity
- 10 Cleaning the camera
- 11 Application examples
- 12 About FLIR Systems
- 13 Glossary
- 14 Thermographic measurement techniques
- 15 History of infrared technology
- 16 Theory of thermography
- 17 The measurement formula
- 18 Emissivity tables
Theory of thermography
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Figure 16.9 Spectral emissivity of three types of radiators. 1: Spectral emissivity; 2: Wavelength; 3: Black-
body; 4: Graybody; 5: Selective radiator.
16.4 Infrared semi-transparent materials
Consider now a non-metallic, semi-transparent body – let us say, in the form of a thick flat
plate of plastic material. When the plate is heated, radiation generated within its volume
must work its way toward the surfaces through the material in which it is partially ab-
sorbed. Moreover, when it arrives at the surface, some of it is reflected back into the inte-
rior. The back-reflected radiation is again partially absorbed, but some of it arrives at the
other surface, through which most of it escapes; part of it is reflected back again.
Although the progressive reflections become weaker and weaker they must all be added
up when the total emittance of the plate is sought. When the resulting geometrical series
is summed, the effective emissivity of a semi-transparent plate is obtained as:
When the plate becomes opaque this formula is reduced to the single formula:
This last relation is a particularly convenient one, because it is often easier to measure
reflectance than to measure emissivity directly.
#T559828; r. AC/ 9610/10386; en-US
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