Thermography
General Description
Thermography is a measurement technique based on the use of Infrared camera(s) to acquire the temperature map of an object (e.g. test specimen). This type of measurement can be performed at ambient conditions, but also in thermal vacuum or in climatic chambers.
The IR camera system available in the ESTEC Test Centre for thermography applications is portable and can be deployed in all the available thermal vacuum chambers. It is based on high resolution thermal cameras, both Medium wavelength (MW) and Long Wavelength (LW), cooled and uncooled. The variety of available devices allows a wide temperature measurement range to be covered.
Medium wave cameras are also geared with Band pass filters that allows the measurements also when the sun simulator is in operation. The use of fibre optics and Ethernet cables for the communication with the IR cameras virtually remove any limitation in the distance between the measurement device and the acquisition unit.
Because of the harsh environment found in thermal vacuum chambers, the IR cameras available in the test centre are either protected by pressurized enclosures, or have been qualified to work under direct exposition to thermal vacuum conditions.
A commercial software is used to control and configure the IR cameras. Thanks to the available features, acquisitions can run unattended for days.
As an accurate measurement of temperature with thermography is strongly influenced by the optical properties of the material under test, a dedicated test bench has been developed and is used for the characterization of the emissivity in the bandwidth of the selected IR camera.
3D Thermography capabilities have also been investigated. Upon request, further development for ad-hoc testing can be offered.
MWIR
Camera type
MWIR
Detector type
InSb
InSb
Detector size
640 x 512 pixels
1280 x 1024 pixels
Spectral response
1.5 – 5.1 µm
3.0 – 5.0 µm
Measurement range
+5⁰C to +350⁰C
-20⁰C to +350⁰C
Cooler
Stirling
Stirling
Thermal resolution
NETD @ 25⁰C < 20mK
NETD @ 25⁰C < 30mK (< 25mK typical)
Optics
12mm F/2 lens
17mm F/2.5 lens
Field of view
43.6⁰ x 33.4⁰
60.1⁰ x 48.6⁰
Electrical Interface
Ethernet and CamLink
Gigabit Ethernet
LWIR
Camera type
LWIR
Detector type
Uncooled Microbolometer
MCT
Detector size
640 x 480 pixels
640 x 512 pixels
Spectral response
7.5 – 14.0 µm
8.0 – 9.4 µm
Measurement range
-40⁰C to +150⁰C
-40⁰C to +150⁰C
Cooler
N/A
Stirling
Thermal resolution
NETD @ 25⁰C < 30mK
NETD @ 25⁰C < 35mK
Optics
13.1mm F/1.0 lens
25mm F/2 lens
Field of view
45.0⁰ x 33.4⁰
23.6⁰ x 18.1⁰
Electrical Interface
Gigabit Ethernet
Ethernet and CamLink