Single-Shot Multiwavelength Imaging of Laser Plumes

A novel optical approach to single-shot chemical imaging with high spectroscopic resolution is described with the use of a prototype dimension-reduction fiber-optic array. Images are focused onto a 30 × 20 array of hexagonally packed 250 μm o.d. f/2 optical fibers that are drawn into a 600 × 1 distal array with specific ordering. The 600 × 1 side of the array is imaged with an f/2 spectrograph equipped with a holographic grating and a charge-coupled device (CCD) camera for spectral analysis. Software is used to extract the spatial/spectral information contained in the CCD images and de-convolute them into wavelength-specific reconstructed images or position-specific spectra that span a 190 nm wavelength space. “White light” zero-order images and first-order spectroscopic images of laser plumes have been reconstructed to illustrate proof-of-principle. Index Headings: Fiber optics; Chemical imaging; Spectroscopic imaging; Charged-coupled device (CCD); Laser-induced breakdown spectroscopy (LIBS).