Share Email Print
cover

Optical Engineering

Three-phase quadrature spectral matching imager using correlation image sensor and wavelength-swept monochromatic illumination
Author(s): Akira Kimachi; Shogo Nishi; Shigeru Ando; Motonori Doi
Format Member Price Non-Member Price
PDF $20.00 $25.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

We propose a three-phase spectral matching imager (3PSMI) to realize a novel spectral matching method called quadrature spectral matching (QSM) in real time. The 3PSMI is comprised of the correlation image sensor (CIS) and wavelength-swept monochromatic illumination (WSMI) to perform QSM at each pixel on the CIS at a video frame rate. QSM consists of spectral correlation between an ac component of an object spectrum and an orthonormal pair of reference spectra, being equivalent to projecting the ac object spectrum onto a two-dimensional subspace spanned by the reference spectra. Similarity of the ac object spectrum to the reference spectra is evaluated in terms of the azimuth angle of the projection, independently of the norm of the ac object spectrum as well as spatial intensity distribution of the WSMI. A programable spectral light source is employed to implement the WSMI so that the spectral characteristics of the WSMI and CIS cancel each other and thus do not affect QSM on the 3PSMI. Experimental results confirm that the developed 3PSMI system can distinguish objects with smaller difference in spectral reflectance in real time than RGB imaging with off-the-shelf cameras.

Paper Details

Date Published: 1 December 2011
PDF: 18 pages
Opt. Eng. 50(12) 127208 doi: 10.1117/1.3662425
Published in: Optical Engineering Volume 50, Issue 12
Show Author Affiliations
Akira Kimachi, Osaka Electro-Communication Univ. (Japan)
Shogo Nishi, Osaka Electro-Communication Univ. (Japan)
Shigeru Ando, The Univ. of Tokyo (Japan)
Motonori Doi, Osaka Electro-Communication Univ. (Japan)


© SPIE. Terms of Use
Back to Top