Digital radiography
Description
Digital radiography is a form of X-ray radiography, where digital detector arrays (DDA) are used instead of traditional radiographic films. Advantages include time efficiency through bypassing chemical processing and the ability to digitally transfer and enhance images. Also less radiation dose (and thus lower exposure time) can be used to produce an image of similar contrast to conventional radiography. Digital radiography can be subdivided in three different techniques, according to the type of detector: - Imaging Plate (IP) - Flat Panel Detector (FPD) - Linear Diode Array (LDA) These three detectors permit to obtain directly a digital image, give advantages of immediate image preview and availability, elimination of film processing steps (economy of time & cost), a potential wider dynamic range, as well as the ability to apply dedicated image processing techniques like contrast enhancement, filtration, zoom, pattern recognition, combination with images obtained by other techniques (visible, IR or UV fluorescence photography…)… However, the high definition (low speed) classical industrial radiographic films permit yet to obtain radiographs with better intrinsic resolving power & radiographic image quality.
NB Digital radiography should not be confused with radioscopy, where there is a continuous beam of radiation, and the images appear on the screen like on a video monitor, where the image of the article being examined is viewed in real time.
radiographie numérique (Fr.)
Additional information
- R.H.Bossi, F. Iddings, G.C. Wheeler, P.O. Moore, Nondestructive testing handbook, vol 4, Radiographic testing, 3rd edition, Columbus OH, ASNT, (2002)