522
D. Ishikawa et al.
22.2.3 Development of Instrument
22.2.3.1 High-Speed Portable NIR Imaging System [5]
To meet the demands of diverse application fields such as pharmaceutics and agriculture, high speed and portability are essential. “D-NIRs” is a portable NIR spectral
imaging system recently developed by Yokogawa Electrics Co., Ltd. D-NIRs is a
point scanning-based system that enables rapid spectral imaging in the 950–1700 nm
region with a maximum spatial resolution of 0.1 mm. For instance, a spectral image
of a sample tablet (diameter; 8 mm) can be obtained within a few seconds. An
overview and schematic diagram of D-NIRs are shown in Fig. 22.4. D-NIR consists
of an NIR spectrometer (“P-NIRs”), imaging unit and light source unit. P-NIR is
a polychromator-type spectrometer, developed by the group of Prof. Ishikawa for
process monitoring. Although the basic system of this spectrometer is similar to
a typical one, the detector of the spectrometer is more sensitive, consisting of a
newly developed high-density InGaAs photodiode array detector of 640 elements
with 20 μm pitch. The photodiode is sensitive to light in the 900–1700 nm wavelength range, and this spectrometer can measure spectra with a 1.25 nm interval in
that range. As shown in Fig. 22.4, the diffuse reflection energy from a sample reaches
the imaging unit of D-NIRs. Mapping for two dimensions (x- and y-directions) is
controlled by two galvanomirrors.
22.2.3.2 Wide-Area NIR Imaging Device with High-Speed
Performance [6]
Wide-area investigation of inhomogeneity for components and/or quality with high
speed is important to process control of various samples, for instance, agri-food products. “Compovision” is a wide-area NIR imaging camera developed by Sumitomo
Electric Industries Ltd (Fig. 22.5). This wide-area and high-speed monitoring system
can measure NIR spectral images of spatial size 150 × 200 mm
2 with spatial
resolution of 0.2 mm in less than 5 s. The high speed is achieved by a newly
developed InGaAs detector which consists of InGaAs/GaAsSb type-II quantum
wells (QWs) laminated on an indium phosphide (InP) substrate. This detector also
contributes to the acquisition of high-quality spectral data in a wide NIR spectral
region (1000–2350 nm).
22.3 Applications of NIR Imaging
NIR spectral imaging has in recent years become the topic of intense research in
highly applied and industrially relevant areas such as food, pharmaceutical, polymer
and biological sample analysis. The following sections provide an overview of the
D. Ishikawa et al.
22.2.3 Development of Instrument
22.2.3.1 High-Speed Portable NIR Imaging System [5]
To meet the demands of diverse application fields such as pharmaceutics and agriculture, high speed and portability are essential. “D-NIRs” is a portable NIR spectral
imaging system recently developed by Yokogawa Electrics Co., Ltd. D-NIRs is a
point scanning-based system that enables rapid spectral imaging in the 950–1700 nm
region with a maximum spatial resolution of 0.1 mm. For instance, a spectral image
of a sample tablet (diameter; 8 mm) can be obtained within a few seconds. An
overview and schematic diagram of D-NIRs are shown in Fig. 22.4. D-NIR consists
of an NIR spectrometer (“P-NIRs”), imaging unit and light source unit. P-NIR is
a polychromator-type spectrometer, developed by the group of Prof. Ishikawa for
process monitoring. Although the basic system of this spectrometer is similar to
a typical one, the detector of the spectrometer is more sensitive, consisting of a
newly developed high-density InGaAs photodiode array detector of 640 elements
with 20 μm pitch. The photodiode is sensitive to light in the 900–1700 nm wavelength range, and this spectrometer can measure spectra with a 1.25 nm interval in
that range. As shown in Fig. 22.4, the diffuse reflection energy from a sample reaches
the imaging unit of D-NIRs. Mapping for two dimensions (x- and y-directions) is
controlled by two galvanomirrors.
22.2.3.2 Wide-Area NIR Imaging Device with High-Speed
Performance [6]
Wide-area investigation of inhomogeneity for components and/or quality with high
speed is important to process control of various samples, for instance, agri-food products. “Compovision” is a wide-area NIR imaging camera developed by Sumitomo
Electric Industries Ltd (Fig. 22.5). This wide-area and high-speed monitoring system
can measure NIR spectral images of spatial size 150 × 200 mm
2 with spatial
resolution of 0.2 mm in less than 5 s. The high speed is achieved by a newly
developed InGaAs detector which consists of InGaAs/GaAsSb type-II quantum
wells (QWs) laminated on an indium phosphide (InP) substrate. This detector also
contributes to the acquisition of high-quality spectral data in a wide NIR spectral
region (1000–2350 nm).
22.3 Applications of NIR Imaging
NIR spectral imaging has in recent years become the topic of intense research in
highly applied and industrially relevant areas such as food, pharmaceutical, polymer
and biological sample analysis. The following sections provide an overview of the