DSP-based MTF measurement system for optical imaging modules

Gao-Wei Chang, Shih Yao Pan

Research output: Contribution to journalConference article

2 Citations (Scopus)

Abstract

With the increasing demand on miniaturization of optical modules, it is important to measure their image quality for consumer electronic devices, such as video cameras, mobile phones, etc. This is because the effect of diffraction arises from the miniaturized optical modules and as a result, it degrades the resolution of the imaging processes. Modulation transfer function (MTF) has been widely recognized as a useful and important tool for assessing the image quality. Therefore, the objective of this paper is to develop a MTF measurement system for the optical modules, on the basis of digital signal processing. In our approach, a spatial light modulator (SLM) is employed to spatially modulate the light, which is emitted from a white-light LED, with the bar patterns of variable frequencies, the modulated light then goes through the module under test, and it is eventually detected by a charge-couple-device (CCD). Obviously, the mapping from the collection of the modulated light to the output images is treated as a computation kernel of the MTF measurement. The corresponding images formed by the optical module are acquired by a digital signal processor (DSP) based system and they are processed by an algorithm for computing the MTF, which is implemented in the system. Finally, it is found that our experiments give quite satisfactory results.

Original languageEnglish
Article number58810T
Pages (from-to)1-8
Number of pages8
JournalProceedings of SPIE - The International Society for Optical Engineering
Volume5881
DOIs
Publication statusPublished - 2005 Dec 29
EventInfrared and Photoelectronic Imagers and Detector Devices - San Diego, CA, United States
Duration: 2005 Jul 312005 Aug 1

Fingerprint

Digital Signal Processor
Optical Imaging
Optical transfer function
Digital signal processors
modulation transfer function
Measurement System
Transfer Function
central processing units
Modulation
modules
Imaging techniques
Module
Image quality
Image Quality
Consumer electronics
Video cameras
Digital signal processing
Mobile phones
Spatial Light Modulator
Light emitting diodes

Keywords

  • Measurement system
  • Modulation transfer function
  • Spatial light modulator
  • Video camera

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Computer Science Applications
  • Applied Mathematics
  • Electrical and Electronic Engineering

Cite this

DSP-based MTF measurement system for optical imaging modules. / Chang, Gao-Wei; Pan, Shih Yao.

In: Proceedings of SPIE - The International Society for Optical Engineering, Vol. 5881, 58810T, 29.12.2005, p. 1-8.

Research output: Contribution to journalConference article

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