In an optical wavelength standard, a concrete matrix embeds wavelength reference material. The concrete matrix is formed from a powdered halogenated polymer (e.g., PTFE) which is mixed with powdered wavelength reference materials, such as rare earth oxides, and the mixture is subjected to sufficient pressure to cause the particles of the halogenated polymer to coalesce into the concrete matrix.
A system for providing and using a gray optical standard is disclosed, the standard generally comprising a housing having a cavity and an at least partially transparent portion adjacent to the cavity for receiving the radiation emitted radiation by an optical instrument and a particulate material disposed in the cavity. The particulate material is a mixture of highly absorptive and highly reflective particles having a diameter of about 20 microns or less. In some embodiments, the at least partially transparent portion of the housing is modified to be highly diffusely scattering in the wavelength region of interest.
The present invention provides a reference standard for calibration of an analysis instrument. The reference standard comprises a solid body formed of a number of compounds and a substrate having scattering properties similar to a product to be analyzed with said analysis instrument and being spectrally neutral in a wavelength range to be used in the analysis instrument. The substrate and the compounds in combination with respect to intensity, wavelength and scattering properties imitate the spectral response of the product to be analyzed with said analysis instrument. The present invention also provides a method for calibration of an analysis instrument, which method comprises recording, by means of said analysis instrument, the spectral response of a reference standard comprising a solid body, which with respect to intensity, wavelength and scattering properties imitates the spectral response of a product to be analyzed with said analysis instrument; evaluating the differences between the response from said analysis instrument and an expected spectral response; and calibrating said analysis instrument according to the result of the evaluation.
A method of characterizing an agricultural product at a location, and analysis system, comprising a sensor 2 for generating data, a central processor 4 for receiving the generated data and manipulating the data to calculate a value of at least one property of the product, and displaying the value in the vicinity of the sensor 2. Information is transmitted between sensor 2, central processor 4 and display 6 using a telecommunication link 8.
A method of analysis, analysis system, program product, apparatus, and method of supplying analysis of value incorporating the use of at least one data acquisition device, a central processor, and a communication link that is connectable between the data acquisition device and the central processor. The central processor is loaded with multivariate calibration models developed for predicting values for various properties of interest, wherein the calibration models are capable of compensating for variations in an effectively comprehensive set of measurement conditions and secondary material characteristics. As so configured, the calibration models can compensate for instrument variance without instrument-specific calibration transfer. Measurement results generated by the central processor can be transmitted to an output device of a user interface.
