Near infrared calibration

The Voyager spacecraft has a large plate mounted on the main bus so that the instruments on the scan platform can view the plate almost normally. The surface of the aluminum plate is chemically etched and scatters light in all directions when illuminated by the Sun. From the visible to 20 /tm, the scattering characteristic is that of a near perfect Lambertian diffuser, as verified by laboratory measurements one or two years before launch. Exposure of the calibration plate to sunlight requires a complex maneuver of the spacecraft Since the telemetry antenna does not point in the Earth direction at that time, such calibration sequences cannot be performed frequently. Cahbrations have been carried out a month or so before and after each planetary encounter, except following the Saturn encounter by Voyager 2, where 

The advantage of calibration with a diffuser plate is clear. The plate attenuates solar radiation to the level suitable for the dynamic range of the radiometer. The reflectivity of a planetary surface is directly compared with the reflectivity of the calibration plate, which was carefully measured before launch. 

The signal, Sp, in volts or in digital numbers (DN), registered by the radiometer, is proportional to the energy reflected from the planetary surface element within the field of view. 

The constant C must be determined in the calibration process is the etendue and r(X) the normalized spectral response function of the radiometer. The intensity, 7p(A), is the spectral radiance emanating from the planetary surface within the field of view. 

When observing the diffuser plate an expression similar to that of Eq. (5.13.20) is obtained. 

---

P.J. Brown, Wavelength selection in multicomponent near-infrared calibration, J. Chemom., 6, 151-161 (1991). 

A.S. El-Hagrasy, F.D Amico and J.K. Drennen III, A process analytical technology approach to near-infrared process control of pharmaceutical powder blending. Part III Quantitative near-infrared calibration for prediction of blend homogeneity and characterization of powder mixing kinetics, J. Pharm. Sci, 95(2), 422-434 (2006). 

B. J. Tenge, F-Test Significance in Near Infrared Calibration and Near Infrared and Mid Infrared Characterization and Calibration Studies of Matrix-Immobilized and Matrix Dispersed Compounds Bearing Amide Groups, Ph.D. Dissertation, University of Washington, Seattle, WA, 1989-... 

Brown, P.J., Wavelength Selection in Multicomponent Near-Infrared Calibration /. Chemom. 1991, 6, 151-161. 

Table 9.2 Near-infrared calibration results for SMZ Form I and Form II in binary and multi-component...

Chen J, Arnold MA, Small GW. Comparison of combination and first overtone spectral regions for near infrared calibration models for glucose and other biomolecules in aqueous solutions. Analytical Chemistry 2004, 76, 5405-5413. 

Tan, H., Sum, S.T., and Brown, S.D., Improvement of a standard-free method for near-infrared calibration transfer, Appl. Spectrosc., 56, 1098-1106, 2002. 

Valous, N. A. Mendoza, F. Sun, D.W. (2010). Emerging non-contact imaging, spectroscopic and colorimetric technologies for quality evaluation and control of hams a review. Trends in Food Science Technology Vol.21, pp. 26-43 Williams, P. C. Sobering, D. (1996). Haw do we do it A brief summary of the methods we use in developing near infrared calibrations. In A. M. C. Davies P. C. Williams (Eds.), Near infrared spectroscopy the future waves (pp. 185-188). Chichester NIR Publications Wilson, A. D. Baietto, M. (2009). Applications and advances in electronic-nose technologies. Sensors Vol.9, pp. 5099-5148... 

Dabakk, E., M. Nilsson, P. Geladi, S. Wold I. Renberg, 1999. Sampling reproducibility and error estimation in near infrared calibration of lake sediments for water quality monitoring. J. Near Infrared Spectrosc. 7 241-250. 

B. Igne, M. N. Hossain, C. A. Anderson, and J. K. Drermen, Near Infrared Calibration Life-Cycle Management of the Active Content of an Oral Dosage Form, presented at SCIX 2013, Milwaukee. 

E. Diaz-Carrillo, A. Munoz-Serrano, A. Alonso-Moraga, J. M. SerradUla-Manrique. Near infrared calibrations for goat s milk components protein, total casein, as-, b- and k-caseins, fat and lactose. J Near Infrared Spectrosc 1 2) 141-146, 1993. 

Tan, H., S.T. Sum, and S.D. Brown, Improvement of a Standard-Free Method for Near-Infrared Calibration Transfer. Appl. Spectrosc., 2002. 56 1098-1106. 

R.S. Andersson, B.G. Osborne, and I.J. Wesley, The application of localisation to near infrared calibration and prediction through partial least squares regression. J. Near Infrared Spectrosc. 11, 39-48 (2003). 

Cogdill, R. P., Anderson, C. A., Delgado, M., Chisholm, R., Bolton, R., Herkert, T, Afnan, A. M. and Drennen III, J. K. Process analytical technology case study Part II. Development and validation of quantitative near-infrared calibrations in support of a process analytical technology application for real-time release. AAPS PharmSciTech. 6(2) E273-E283, 2005. 

Near-Infrared Calibration Wavelengths for Prism Spectrometers — Absorption Standards... 

Plyler and Peters have published near-infrared calibration wavelengths for prism spectrometers based on the emission of a Hg AH-4 lamp, and reported to the nearest 0.1 A. Rounded to the nearest m/i, they are ... 

---