A method for evaluating luminance non-uniformity of displays by use of a commercially available digital camera

Keishin Kawamoto, Shogo Tokurei, Junji Morishita

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

The luminance uniformity of liquid–crystal displays (LCDs) deteriorates with their prolonged use. In this paper, we present a method for evaluating the degree of luminance non-uniformity of LCDs with the use of a commercially available digital camera. In this study, seven monochrome LCDs, which were used during various operating times ranging from 5000 to 25,000 h, were evaluated with use of a camera. The maximum luminance deviation (MLD) was measured on the two-dimensional (2D) images obtained with the camera. In addition, an index of the luminance non-uniformity was calculated as the ratio of the area exhibiting luminance non-uniformity to the area of the entire LCD screen. We determined the area with the luminance non-uniformity by setting the allowable luminance deviation as the judgment criterion to evaluate the degree of luminance non-uniformity. The MLD values were less than 20% for all conditions, and they varied depending on the locations of the luminance measurement. The area ratios of the luminance non-uniformity based on 2D luminance distributions tended to increase with the duration of use of LCDs, and they indicated the degree of luminance non-uniformity of the LCDs regardless of the measurement locations. Our approach of using a commercially available digital camera showed its potential usefulness for providing more detailed and consistent evaluations of the degree of luminance non-uniformity of LCDs based on the 2D luminance distributions.

Original languageEnglish
Pages (from-to)409-414
Number of pages6
JournalRadiological physics and technology
Volume10
Issue number4
DOIs
Publication statusPublished - Dec 1 2017

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digital cameras
luminance
nonuniformity
deviation
cameras

All Science Journal Classification (ASJC) codes

  • Radiation
  • Physical Therapy, Sports Therapy and Rehabilitation
  • Radiology Nuclear Medicine and imaging

Cite this

A method for evaluating luminance non-uniformity of displays by use of a commercially available digital camera. / Kawamoto, Keishin; Tokurei, Shogo; Morishita, Junji.

In: Radiological physics and technology, Vol. 10, No. 4, 01.12.2017, p. 409-414.

Research output: Contribution to journalArticle

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