Article ID Journal Published Year Pages File Type
1685226 Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 2012 4 Pages PDF
Abstract

Whilst commercial X-ray sensor arrays are capable of both imaging and spectroscopy they are currently expensive and this can limit their widespread use. This study examines the use of very low cost CMOS sensors for X-ray imaging and spectroscopy based on the commercial off the shelf (COTS) technology used in cellular telephones, PC multimedia and children’s toys. Some examples of imaging using a ‘webcam’ and a modified OmniVision OV7411 sensor are presented, as well as a simple energy dispersive X-ray detector based on an OmniVision OV7221 sensor. In each case X-ray sensitivity was enabled by replacing the sensor’s front glass window with a 5 μm thick aluminium foil, with X-rays detected as an increase in a pixel’s dark current due to the generation of additional electron–hole pairs within its active region. The exposure control and data processing requirements for imaging and spectroscopy are discussed. The modified OV7221 sensor was found to have a linear X-ray energy calibration and a resolution of approximately 510 eV.

Related Topics
Physical Sciences and Engineering Materials Science Surfaces, Coatings and Films
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