Needle vs. Powder Imaging Plate for Computer Radiography: Image Quality Measurement and Model Calculation
Abstract:Computed radiography (CR) is a digital radiography technology in which a storage phosphor plate is used to store a latent X-ray image. The plate is exposed in a light-tight cassette and then read out in a scanner to create the digital image. Conventionally, CR powder imaging plates (PIP) are used based on BaFBr1-xIx:Eu2+ phosphor. The active layer consists of phosphor microcrystals in a polymer binder. A needle imaging plate (NIP), created by of vapor deposition of needle-shaped phosphor crystals, leads to better image quality because thicker phosphor layers, having higher X-ray absorption can be used. BaFBr1-xIx:Eu2+ is an excellent storage phosphor. It decomposes upon vaporization, however. For that reason, it is impossible to vapor deposit BaFBr1-xIx:Eu2+ needle crystals. At Agfa an excellent new storage phosphor, CsBr:Eu2+, was discovered. Since CsBr melts congruently, it allows thermal vapor deposition and production of NIP's. Measurements demonstrate that CsBr:Eu2+ NIP's allow to double CR image quality (DQE). A linear-systems approach is used to model signal and noise transfer in a CR system using PIP or NIP. The transfers are described by cascading transfer relationships for each process. The calculated image quality (DQE) is in good agreement with measurement for the PIP system. The model overestimates the NIP system DQE at high spatial frequencies. An overestimation of the system gain may be the reason.
Document Type: Research Article
Publication date: January 1, 2005
For more than 25 years, NIP has been the leading forum for discussion of advances and new directions in non-impact and digital printing technologies. A comprehensive, industry-wide conference, this meeting includes all aspects of the hardware, materials, software, images, and applications associated with digital printing systems, including drop-on-demand ink jet, wide format ink jet, desktop and continuous ink jet, toner-based electrophotographic printers, production digital printing systems, and thermal printing systems, as well as the engineering capability, optimization, and science involved in these fields.
Since 2005, NIP has been held in conjunction with the Digital Fabrication Conference.
- Information for Authors
- Submit a Paper
- Subscribe to this Title
- Membership Information
- Terms & Conditions
- ingentaconnect is not responsible for the content or availability of external websites