Linear diode array

Part of a 12-inch (304 mm) 50-micrometre-resolution linear diode array XB8850-12 made by X-Scan Imaging Corporation; a horizontal, white scintillator 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, 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.