• Title/Summary/Keyword: Beam-stop array

Search Result 2, Processing Time 0.02 seconds

Measurement and Evaluation of Scatter Fractions for Digital Radiography with a Beam-Stop Array (Beam-Stop Array를 이용한 DR에서의 Scatter Fraction 측정 및 효용성 평가)

  • Choi, Yu-Na;Cho, Hyo-Min;Kim, Yi-Seul;An, Su-Jung;Kim, Hee-Joung
    • Progress in Medical Physics
    • /
    • v.21 no.1
    • /
    • pp.9-15
    • /
    • 2010
  • Scatter radiation considerably affects radiographic image quality by reducing image contrast and contributing to a non-uniform background. Images containing a large portion of scatter radiation may result in an incorrect diagnosis. In the past few years, many efforts have been made to reduce the effects of scatter radiation on radiographic images. The purpose of this study is to accurately measure scatter fractions and evaluate the effectiveness of beam-stop arrays. To measure scatter fraction accurately, a beam-stop array and the SFC (Scatter Fraction Calculator) program were developed. Images were obtained using the beam-stop array for both an anti-scatter technique with an anti-scatter grid and an air gap technique. The scatter fractions of the images were measured using the SFC program. Scatter fractions obtained with an anti-scatter grid were evaluated and compared to scatter fractions obtained without an anti-scatter grid. Scatter fractions were also quantitatively measured and evaluated with an air gap technique. The effectiveness of the beam-stop array was demonstrated by quantifying scatter fractions under various conditions. The results showed that a beam-stop array and the SFC program can be used to accurately measure scatter fractions in radiographic images and can be applied for both developing scatter correction methods as well as systems.

Liquid Crystal Display Mode with a Single Polarizer based on Switchable Microlens Arrays

  • Kim, Young-Wook;Gwag, Jin-Seog;Lee, Se-Hyun;Jeong, Ji-Won;Kim, Jae-Hoon;Yu, Change-Jae
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2009.10a
    • /
    • pp.620-622
    • /
    • 2009
  • We demonstrated a liquid crystal display (LCD) mode with a single polarizer based on the array of a switchable microlens consisting of a circular stop mask and its complementary open mask. The focused beam passed through the open mask and thus the bright state was obtained, while the defocused beam was blocked by the stop mask and the complementary open mask. It is expected that our single-polarizer LCD mode is applicable to low cost displays.

  • PDF