Optical Review

, Volume 26, Issue 6, pp 720–728 | Cite as

Color speckle measurement of white laser beam emitted from fiber output of RGB laser modules

  • Junichi KinoshitaEmail author
  • Keizo Ochi
  • Akira Takamori
  • Kazuhisa Yamamoto
  • Kazuo Kuroda
  • Koji Suzuki
  • Keisuke Hieda
Special section: Regular Paper Laser Display and Lighting Conference (LDC’ 19), Yokohama, Japan
Part of the following topical collections:
  1. Laser Display and Lighting Conference (LDC' 19), Yokohama, Japan


Color speckle metrics of an RGB-combined white laser beam emitted from an optical fiber output of two types of RGB laser module are measured. A new method for eliminating the effects of a fiber far field pattern from the measured 2D speckle data is employed to calculate the speckle metrics with a statistical accuracy. In this method, unspeckled 2D data of the far field pattern can be directly measured by opening the iris of the speckle measurement equipment. As a result, white photometric speckle contrast and color speckle distribution in CIE1931 chromaticity diagram are, for the first time, successfully obtained by eliminating the far field pattern effects.


Speckle Color speckle Laser module Far field pattern Optical fiber 



This work is supported by Strategic International Standardization, Ministry of Economics, Trade and Industry, Japan.


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Copyright information

© The Optical Society of Japan 2019

Authors and Affiliations

  1. 1.Institute of Laser EngineeringOsaka UniversitySuitaJapan
  2. 2.Center for Optical Research and EducationUtsunomiya UniversityUtsunomiyaJapan
  3. 3.Oxide CorporationKawasakiJapan

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