User's Manual
Table Of Contents
- 1 Disclaimers
- 2 Safety information
- 3 Notice to user
- 4 Customer help
- 5 Quick start guide
- 6 Register the camera
- 7 A note about ergonomics
- 8 Camera parts
- 9 Screen elements
- 10 Navigating the menu system
- 11 Handling the camera
- 11.1 Charging the battery
- 11.2 Installing and removing the camera battery
- 11.3 Turning on and turning off the camera
- 11.4 Adjusting the angle of lens
- 11.5 Adjusting the infrared camera focus manually
- 11.6 Autofocusing the infrared camera
- 11.7 Continuous autofocus
- 11.8 Operating the laser distance meter
- 11.9 Measuring areas
- 11.10 Connecting external devices and storage media
- 11.11 Moving files to a computer
- 11.12 Assigning functions to the programmable buttons
- 11.13 Using the camera lamp as a flash
- 11.14 Changing camera lenses
- 11.15 Neck strap
- 11.16 Hand strap
- 12 Saving and working with images
- 13 Working with the image archive
- 14 Achieving a good image
- 15 Working with image modes
- 16 Working with measurement tools
- 17 Working with color alarms and isotherms
- 18 Annotating images
- 19 Programming the camera (time-lapse)
- 20 Recording video clips
- 21 Screening alarm
- 22 Pairing Bluetooth devices
- 23 Configuring Wi-Fi
- 24 Fetching data from external FLIR meters
- 25 Changing settings
- 26 Cleaning the camera
- 27 Technical data
- 27.1 Online field-of-view calculator
- 27.2 Note about technical data
- 27.3 Note about authoritative versions
- 27.4 FLIR T530 24°
- 27.5 FLIR T530 42°
- 27.6 FLIR T530 24° + 14°
- 27.7 FLIR T530 24° + 42°
- 27.8 FLIR T530 24° + 14° & 42°
- 27.9 FLIR T530 42° + 14°
- 27.10 FLIR T540 24°
- 27.11 FLIR T540 42°
- 27.12 FLIR T540 24° + 14°
- 27.13 FLIR T540 24° + 42°
- 27.14 FLIR T540 24° + 14° & 42°
- 27.15 FLIR T540 42° + 14°
- 28 Mechanical drawings
- 29 Application examples
- 30 About FLIR Systems
- 31 Terms, laws, and definitions
- 32 Thermographic measurement techniques
- 33 The secret to a good thermal image
- 34 About calibration
- 34.1 Introduction
- 34.2 Definition—what is calibration?
- 34.3 Camera calibration at FLIR Systems
- 34.4 The differences between a calibration performed by a user and that performed directly at FLIR Systems
- 34.5 Calibration, verification and adjustment
- 34.6 Non-uniformity correction
- 34.7 Thermal image adjustment (thermal tuning)
- 35 History of infrared technology
- 36 Theory of thermography
- 37 The measurement formula
- 38 Emissivity tables
The measurement formula
37
As already mentioned, when viewing an object, the camera receives radiation not only
from the object itself. It also collects radiation from the surroundings reflected via the ob-
ject surface. Both these radiation contributions become attenuated to some extent by the
atmosphere in the measurement path. To this comes a third radiation contribution from
the atmosphere itself.
This description of the measurement situation, as illustrated in the figure below, is so far
a fairly true description of the real conditions. What has been neglected could for in-
stance be sun light scattering in the atmosphere or stray radiation from intense radiation
sources outside the field of view. Such disturbances are difficult to quantify, however, in
most cases they are fortunately small enough to be neglected. In case they are not negli-
gible, the measurement configuration is likely to be such that the risk for disturbance is
obvious, at least to a trained operator. It is then his responsibility to modify the measure-
ment situation to avoid the disturbance e.g. by changing the viewing direction, shielding
off intense radiation sources etc.
Accepting the description above, we can use the figure below to derive a formula for the
calculation of the object temperature from the calibrated camera output.
Figure 37.1 A schematic representation of the general thermographic measurement situation.1: Sur-
roundings; 2: Object; 3: Atmosphere; 4: Camera
Assume that the received radiation power W from a blackbody source of temperature
T
source
on short distance generates a camera output signal U
source
that is proportional to
the power input (power linear camera). We can then write (Equation 1):
or, with simplified notation:
where C is a constant.
Should the source be a graybody with emittance ε, the received radiation would conse-
quently be εW
source
.
We are now ready to write the three collected radiation power terms:
1. Emission from the object = ετW
obj
, where ε is the emittance of the object and τ is the
transmittance of the atmosphere. The object temperature is T
obj
.
#T810253; r. AA/42549/42549; en-US
205