Compressive spectral imaging with diffractive lenses

Kar, Oguzhan Fatih
Öktem, Sevinç Figen
Compressive spectral imaging enables the reconstruction of an entire 3D spectral cube from a few multiplexed images. Here we develop a novel compressive spectral imaging technique using diffractive lenses. Our technique uses a coded aperture to spatially modulate the optical field from the scene and a diffractive lens such as a photon sieve for both dispersion and focusing. Measurement diversity is achieved by changing the focusing behavior of the diffractive lens. The 3D spectral cube is then reconstructed from highly compressed measurements taken with a monochrome detector. A fast sparse recovery method is developed to solve this large-scale inverse problem. The performance is illustrated for various scenarios with different compression ratios through simulations. The results demonstrate that promising reconstruction performance can be achieved at high compression levels. This opens up new possibilities for high-resolution spectral imaging with simpler and low cost designs. (C) 2019 Optical Society of America


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Citation Formats
O. F. Kar and S. F. Öktem, “Compressive spectral imaging with diffractive lenses,” OPTICS LETTERS, pp. 4582–4585, 2019, Accessed: 00, 2020. [Online]. Available: