Infrared Detector Utilized in Ultrahigh Resolution Imaging

Brief Description

An inexpensive infrared detector with a dramatically improved signal-to-noise ratio and greater sensitivity.

Background

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.

Description

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. 

Advantages

• A dramatically improved signal-to-noise ratio allowing for greater sensitivity
• The potential to extend upconverted light into the visible range
• Easy scalability for high spatial resolution imaging applications

Applications

• Cell imaging
• Pollution detection
• Defense: rocket and reactor emissions evaluation           
• Radio-astronomy

Patent Status