Single-shot fourier transform multispectroscopy

Abstract

Compared to color imaging, hyperspectral imaging (HSI) has a significant advantage in identifying the objects based on their material spectral characteristics. Though multispectral imaging (MSI) is intended to overcome the speed and spatial resolution limitations of the HSI modalities, it pays severe penalties in detection and recognition tasks. In this article, we propose a novel MSI modality by designing a spectral filter array (SFA) based on the Fourier transform spectroscopy. We refer to this new SFA pattern as Fourier SFA. Compared to the MSI modalities based on narrowband filtering, Fourier SFA reconstructs spectral features more faithfully.

Guided Filter Demosaicking For Fourier Spectral Filter Array

“…Appealing to the fact that each interferometric measurement is equivalent to taking inner product between a sinusoidal function and the full spectrum in the wavenumber domain, we replaced the narrowband filter with broadband filters whose transmittance follows sinusoidal shape, a process by which we obtain interferometric measurements at every pixel. We proved that Fourier spectroscopy-based MSI preserves spectral features more accurately than the narrowband MSI [11], and proposed spatial arrangements of SFA using these sinusoidal filters (hereafter referred to as Fourier SFA) [10]. In our earlier work, less emphasis was placed on the demosaicking procedure.…”

“…We recently proposed a novel MSI based on Fourier transform spectroscopy [10], aimed at presenting the spectral features of interest with fewest spectral samples. Appealing to the fact that each interferometric measurement is equivalent to taking inner product between a sinusoidal function and the full spectrum in the wavenumber domain, we replaced the narrowband filter with broadband filters whose transmittance follows sinusoidal shape, a process by which we obtain interferometric measurements at every pixel.…”

“…In our earlier work, less emphasis was placed on the demosaicking procedure. In this paper, we investigate the feasibility of repurposing demosaicking method in [5] for the Fourier SFA pattern in [10].…”

Fourier multispectral imaging

“…With no aliasing, demosaicking can be also implemented as a linear demodulation[23,24,26] which we discussed in Chapter 5.3. From the physical implantation point of view, although the performance of the system improves, the complexity of the production also increases.CHAPTER VI FOURIER SFA FABRICATIONFor testing purpose, a spatially multiplexed spectral filter array was designed and fabricated based on the pixel configuration discussed in[27]. Each unit cell consists of four distinct Fourier spectral filters, as shown inFig 6.1.…”

N-LMMSE Demosaicing for Spectral Filter Arrays

“…51,52 Compressive sensing to compensate for the increasing sparsity have also been used successfully. [53][54][55] Specific to technology, such as Fourier SFA 56,57 and hybrid multi-camera approaches 58 and specific to application demosaicing 59 have also been developed.…”