The image quality characteristics of a novel ultra-high-resolution film/screen system

Beutel, Jacob; Mickewich, Daniel J.; Issler, Sandra L.; Shaw, Rodney

doi:10.1088/0031-9155/38/9/002

Cited by 18 publications

(8 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The values of DQE peaked at 80 kVp and 80 mg/cm 2 , attaining a value of 0.312. This value is accurate within the limits of experimental errors [5,6] and is also within the limits of values published by previous studies [6,14,15] on commercial systems. Figure 3 shows the variation NEP with increasing Xray tube voltage for various Gd 2 O 2 S:Tb±La 2 O 2 S:Tb phosphor mixtures in varying proportions.…”

Section: Theoretical Calculationssupporting

confidence: 85%

“…This calculation, however, includes the MTF of the scanner and of the film. To obtain the screen MTF the data were corrected by dividing with the MTF of the scanner, whereas the film's MTF was considered equal to unity for frequencies up to 100 lp/cm [14,19,21]. The MTF uncertainties were between 0.7 %, at low spatial frequencies and thin screens, and 3 % at high frequencies and thick screens.…”

Section: Mtf Determinationmentioning

confidence: 99%

“…The light emission efficiency [1,2,3,4,5,6,7,8,9,10,16], which was evaluated by determining the number of emitted photons (NEP) of light per incident X-ray 2. The modulation transfer function (MTF), which describes the variation of image contrast with spatial frequency and expresses spatial resolution [5,10,11,12,13,14]. 3.…”

mentioning

confidence: 99%

“…3. The detective quantum efficiency (DQE), which expresses the transfer of the SNR from the input to the output of an imaging system [6,10,11,12,13,14,15,17].…”

mentioning

confidence: 99%

See 3 more Smart Citations

Experimental and theoretical assessment of the performance of Gd2O2S:Tb and La2O2S:Tb phosphors and Gd2O2S:Tb–La2O2S:Tb mixtures for X-ray imaging

Kandarakis

Cavouras

2001

Eur Radiol

View full text Add to dashboard Cite

The purpose of this work was to investigate and compare the imaging performance of Gd2O2S:Tb and La2O2S:Tb phosphors as well as of Gd2O2S:Tb and La2O2S:Tb mixtures for use in X-ray imaging detectors (intensifying screens). Phosphors were supplied in powder form and were used to prepare test screens. Three types of screens were prepared: Gd2O2S:Tb; (Gd50La50)O2S:Tb; and La2O2S:Tb. Screens were excited by X-rays with tube voltages from 40 to 120 kV and their efficiency (light intensity or light energy flux over exposure) was measured with a photomultiplier and a dosimeter. The light spectrum was also measured with a monochromator. From these measurements, the number of emitted photons per incident X-ray (NEP) and the zero frequency detective quantum efficiency (DQE(0)) of the screens were determined. Additionally, modulation transfer function (MTF) was measured by the square wave response function (SWRF) method. A theoretical model calculating NEP and DQE was also developed to fit experimental data and predict the performance of Gd2O2S:Tb-La2O2S:Tb mixtures by weight from 10-90% to 90-10%. Gd2O2S:Tb screens exhibited highest NEP, DQE, and MTF at tube voltages higher than 55 kV and lower than 45 kV, whereas La2O2S:Tb screens had better NEP, DQE, and MTF within the 45- to 55-kV range. Maximum NEP values were higher than 700 at 100-120 kV while maximum DQE(0) was 0.314 at 80 kV. Gd2O2S:Tb screens are more efficient for high X-ray tube voltage applications (e.g., abdominal imaging, chest radiography, lumbar spine radiography, CT) and for very low voltage applications (e.g., mammography). La2O2S:Tb screens are useful for medium-range X-ray voltages (e.g., pediatric radiography).

show abstract

Section: Theoretical Calculationssupporting

confidence: 85%

Section: Mtf Determinationmentioning

confidence: 99%

mentioning

confidence: 99%

“…3. The detective quantum efficiency (DQE), which expresses the transfer of the SNR from the input to the output of an imaging system [6,10,11,12,13,14,15,17].…”

mentioning

confidence: 99%

See 2 more Smart Citations

Experimental and theoretical assessment of the performance of Gd2O2S:Tb and La2O2S:Tb phosphors and Gd2O2S:Tb–La2O2S:Tb mixtures for X-ray imaging

Kandarakis

Cavouras

2001

Eur Radiol

View full text Add to dashboard Cite

show abstract

“…Replacement of visible-light-emitting phosphors with UV-emitting M}YTaO was found to signi"cantly improve radiographic image sharpness (4,5). There are two reasons for the improvement in image quality.…”

Section: Introductionmentioning

confidence: 99%

A New High-Efficiency UV-Emitting X-Ray Phosphor, BaHf1−xZrx(PO4)2

Miao¹,

Torardi²

2000

Journal of Solid State Chemistry

View full text Add to dashboard Cite

Integrated model for estimating phosphor signal and noise transfer characteristics on medical images: application to CdPO3Cl:Mn phosphor screens

Cavouras

Kandarakis

Panayiotakis

et al. 2002

Med. Biol. Eng. Comput.

View full text Add to dashboard Cite

An integrated model describing the signal and noise transfer characteristics of the objective image quality and information content in phosphor-produced images is presented. In the context of this model, important imaging parameters, namely optical gain, modulation transfer function, noise transfer function, detective quantum efficiency and information capacity were experimentally evaluated using seven laboratory-prepared CdPO3Cl:Mn test phosphor screens of varying coating thickness. This phosphor has been previously shown to exhibit high spectral compatibility properties with the films and optical sensors used in digital imaging systems. Experiments were performed using 50-120 kVp X-rays produced by a medical X-ray unit. Results showed that, for thick screens, optical gain attained peak values close to 200 optical photons per incident X-ray at 50 kVp. The noise transfer function was higher than the modulation transfer function. For the thin screen of 21 mg cm-2, the modulation transfer function was 0.25 at 100 line pairs mm-1, and the corresponding noise transfer function was 0.4. The detection quantum efficiency peak value was 0.22 at 50 kVp. These values are within acceptable performance limits, and, given the phosphor material's high spectral compatibility and medium temporal response, CdPO3Cl:Mn could be considered for use in X-ray detectors of static radiography imaging.

show abstract

The image quality characteristics of a novel ultra-high-resolution film/screen system

Cited by 18 publications

References 1 publication

Experimental and theoretical assessment of the performance of Gd2O2S:Tb and La2O2S:Tb phosphors and Gd2O2S:Tb–La2O2S:Tb mixtures for X-ray imaging

Experimental and theoretical assessment of the performance of Gd2O2S:Tb and La2O2S:Tb phosphors and Gd2O2S:Tb–La2O2S:Tb mixtures for X-ray imaging

A New High-Efficiency UV-Emitting X-Ray Phosphor, BaHf1−xZrx(PO4)2

Integrated model for estimating phosphor signal and noise transfer characteristics on medical images: application to CdPO3Cl:Mn phosphor screens

Contact Info

Product

Resources

About