Prof. P. Apte of Department of Electrical Engineering and his colleague
of Department of Mechanical Engineering and
their students from have been able to develop an opto-thermo-mechanical integrated
uncooled imaging system that captures
the thermal images for direct coloured display of thermal images. Thermal
imaging is used in applications such as
night vision, environmental monitoring, astronomy, biomedical diagnostics,
and thermal probing of microelectronic
devices.
The invention collects infrared radiation which passes through an
infrared lens system and forms an image onto the device.
The system works in the following way. IR radiation passes through a special
substrate in the lower diaphragm and gets
absorbed in the upper diaphragm of the array. The heat absorbed gets conducted
to the substrate through displaceable
bimorph members linked to the diaphragm. Heated bimorph members cause deflection
that raises the upper diaphragm.
White light incident on the upper diaphragm causes constructive interference
of a specific colour in visible light range. The end result of this
process is that a direct colour image can be generated.
Some features:
- IR sensing and coloured image display capability
- Room temperature operation
- No cryogenic cooling equipment required
- Inherent room temperature compensation
- No further image processing of captured IR images needed
A direct coloured
display of images is formed by the system without any processing device
or electronics, intervening electronics or electrical
connections
and reduced thermal cross-talk between neighbouring pixels. No
internal heat is generated due to the absence of electrical current.
The
device is simple and robust and has minimal number of parts.
Indian patent application no. 541/MUM/2005 Patent grant no. 236126
Inventors: P Apte, B Seth, O Karhade, and S Chiluveru
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