Linear diode array

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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 XB8850-12 LDA.JPG
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. [1] 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.

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References

  1. Pearsall, Thomas (2010). Photonics Essentials, 2nd edition. McGraw-Hill. ISBN   978-0-07-162935-5. Archived from the original on 2021-08-17. Retrieved 2021-02-25.