Linear diode array
File:XB8850-12 LDA.JPG strip overlays a linear silicon-integrated photodiode array mounted by chip-on-board surface-mount technology onto a green printed-circuit board]]
A Linear diode array is used for digitizing x-ray images. The LDA system consists of an array of photodiode modules.{{cite book|last1=Pearsall|first1=Thomas|title=Photonics Essentials, 2nd edition|publisher=McGraw-Hill|date=2010|url=https://www.mheducation.com/highered/product/photonics-essentials-second-edition-pearsall/9780071629355.html|isbn=978-0-07-162935-5|access-date=2021-02-25|archive-date=2021-08-17|archive-url=https://web.archive.org/web/20210817005021/https://www.mheducation.com/highered/product/photonics-essentials-second-edition-pearsall/9780071629355.html|url-status=dead}} The diodes are laminated with a scintillation screen to create x-ray sensitive diodes. The scintillation screen converts the photon energy emitted by the x-ray tube into visible light on the diodes. The diodes produce a voltage when the light energy is received. This voltage is amplified, multiplexed, and converted to a digital signal.
Use
One of the unique characteristics of the LDA is that it has an excellent dynamic range. This means that it is capable of generating useful data when x-raying both very thick (tread) and thin (sidewall) sections of a tire simultaneously. However, the human eye is capable of visualizing only a small fraction of the LDA's full dynamic range. To compensate for the limitations of the human eye while still taking advantage of this feature of the LDA, a variety of selectable contrast and brightness enhancing tables are available.