An inexpensive infrared detector with a dramatically improved signal-to-noise ratio and greater sensitivity.
The use of semiconductor materials has brought a new means for the detection and use of infrared radiation in the mid- and far-infrared regions (M&FIR). Infrared detectors that can measure wavelengths in the M&FIR region can be useful in many fields, such as pollution detection and thermal imaging. Two ways that scientists currently measure M&FIR is through the development of semiconductor quantum well infrared detectors (QWIP) and through indium antimonide (InSb) bonded to a silicon chip. Both of these methods have low efficiency and are very costly.
Researchers at the University of California have developed an inexpensive infrared detector with a dramatically improved signal-to-noise ratio and greater sensitivity. The proposed device converts the signal from an IR or MIR source into a visible or near-visible signal or image. The device does this by upconverting the energy of infrared photons in the 50 meV to 200 meV range (corresponding to wavelengths from 6 to 250 microns), yielding infrared photons of higher energy. These higher energy photons can be easily imaged with a Si CCD camera. An ultimate resolution of 50 nm can be achieved in the imaging mode using a near-field scanning optical microscope for reading the upconverted image, which also gives the device the ability to image live cells for long periods of time.
|United States Of America||Issued Patent||6,541,788||04/01/2003||1999-039|
infrared, thermal imaging, cell imaging, microscope, indmicroscopy