P4 - Development of an IR Microbolometer Camera for Operation in a Strong Magnetic Field
- Event
- SENSOR+TEST Conferences 2011
2011-06-07 - 2011-06-09
Nürnberg - Band
- Proceedings IRS² 2011
- Chapter
- IP - Poster Session
- Author(s)
- D. Wassilew, U. Hoffmann - DIAS Infrared GmbH, Dresden (Germany), D. Hildebrandt - Max Planck Institute for Plasma Physics, Greifswald (Germany)
- Pages
- 115 - 118
- DOI
- 10.5162/irs11/ip4
- ISBN
- 978-3-9810993-9-3
- Price
- free
Abstract
In the present paper an uncooled microbolometercamera with 640x480 pixel is described developed for operation in strong stationary magnetic fields with a magnetic flux density of 3T as occurred in the experimental fusion stellarator Wendelstein7-X currently being constructed at the Max-Planck-Institut für Plasmaphysik in Greifswald. The infrared viewing systems in Wendelstein 7-X are required for monitoring critical components of the device as the divertor target plates with a spatial and temporal resolution of 10 mm and 100 ms, respectively. The developed camera system contains a state-ofthe-art infrared detector with 640 x 480 pixels and has a Gigabit Ethernet interface. It features a temperature range of 0 °C to 1800 °C, a special wide-angle lens with FOV of 116° x 82°, a pneumatically driven shutter and consists of two boxes. The first one includes the sensor housing with parts not sensitive to the magnetic field. The second one is the electronics box which contains all
parts expected to fail in high magnetic fields. Both the sensor housing and the electronics box are sealed to IP54 standard with a rugged housing that holds up well in environments where water and dust resistance is required. Screened cable connections between them provide protection from alien crosstalk and electro magnetic interference. Signal processing is performed by a PC connected with the camera system. Corrections that refine the accuracy of temperature measurement are carried out by the firmware within the camera. Only corrected images are provided. Data transfer between camera system and PC takes place over Gigabit Ethernet by using of standard protocols (IP). Powerful online software under Windows® allows the camera system to visualise, record, analyse and store the measured data. Furthermore an online and offline program interface is available. Efforts are made for data transfer in real time. An extern trigger input for control of the image data is supplied.
Experiments in a magnetic resonance tomography have shown that the sensor box well operates in a magnetic field of 3T. The electronics box still operates satisfactorily in magnetic fields of 30 mT or 50 mT depending on the orientation of the magnetic field.