A Speckle-Enhanced Prism Spectrometer With High Dynamic Range

Cetindag S. K., Toy M. F., Ferhanoğlu O., Çivitci F.

IEEE PHOTONICS TECHNOLOGY LETTERS, vol.30, no.24, pp.2139-2142, 2018 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 30 Issue: 24
  • Publication Date: 2018
  • Doi Number: 10.1109/lpt.2018.2879247
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.2139-2142
  • Istanbul Technical University Affiliated: Yes


We present a novel spectrometer device offering a wide wavelength range and high resolution. The device builds upon a conventional prism spectrometer; however, an additional scattering medium is introduced to generate a wavelength-dependent speckle pattern on the detector array. Simultaneous use of the prism and the scattering medium allows for both improved resolution and wavelength range. The generated speckle pattern secures a significant improvement in the resolution (up to 100 folds) and dynamic range over a conventional prism spectrometer. With the proposed spectrometer, implemented using a CCD camera, we demonstrate up to 17-pm resolution at 855-nm central wavelength and 756.5-nm wavelength range revealing a dynamic range of similar to 44 500. The dynamic range could be further improved upon using a detector array having larger area and a scattering medium offering a nar-rower spectral correlation function. With further development, the proposed device could be useful in a variety of spectroscopy applications, such as deep imaging of retinal layers in optical coherence tomography.