Oral Radiology

, 16:73 | Cite as

Effects of scanning resolution and digital image magnification on photostimulable phosphor imaging system

  • Takashi Sakurai
  • Masafumi Inagaki
  • Hideomi Asai
  • Atsushi Koyama
  • Isamu Kashima
Original Article



To examine the effects of changes in scanning resolution and digital magnification on the image quality and diagnostic ability of the photostimulable phosphor imaging system.


Using a photostimulable phosphor imaging system, images of a human adult dried mandible phantom embedded in a 25 mm-thick epoxy resin block were made. The latent images on the photostimulable phosphor imaging plate were scanned using four different pixel sizes as follows: 25μm×25μm, 50μm×50μm, 100μm×100μm and 200μm×200μm. A primary image was produced for each pixel size. These images were also digitally magnified at powers of 2, 4 and 8 times. The gradient range, brightness and contrast of each image were adjusted to optimum levels on a cathode ray tube display, and hard copies were produced with a writing pixel size of 60μm×60μm. The granularity, sharpness and anatomical diagnostic ability of the images were assessed subjectively by eight dentists.


Increasing the scanning resolution tended to generally improve image quality and diagnostic ability. Visual image quality was maintained up to a pixel size of 50 μm, and diagnostic ability was maintained up to a pixel size of 100μm. Digital image magnification degrated image quality, and more than 2-times magnification degraded diagnostic ability.


Under the present experimental conditions, increasing the scanning resolution did not always lead to an improvement in image quality or diagnostic ability, and digital image magnification degraded image quality and diagnostic ability.

Key Words

Photostimulable phosphor imaging system Scanning resolution Digital magnificatio 


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Copyright information

© Japanese Society for Oral and Maxillofacial Radiology 2000

Authors and Affiliations

  • Takashi Sakurai
    • 1
  • Masafumi Inagaki
    • 1
  • Hideomi Asai
    • 1
  • Atsushi Koyama
    • 1
  • Isamu Kashima
    • 1
  1. 1.Department of Oral and Maxillofacial RadiologyKanagawa Dental CollegeKanagawaJapan

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