Abstract
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 ~44 500. The dynamic range could be further improved upon using a detector array having larger area and a scattering medium offering a narrower 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.
M. Fatih Toy
Associate Professor of Electrical and Electronics Engineering
My research interests include digital holography, quantitative phase imaging, optical diffraction tomography and optical superresolution.
