Abstract:
A method of obtaining high dynamic range, spectrally, spatially and angularly resolved radiance of a sample surface of a sample, such as a paper sheet, accomplished by an electromagnetic irradiator irradiating electromagnetic radiation of controlled spectral distribution onto a sample surface of a sample and, using an electromagnetic sensitive sensor to register the reflected spectral distribution. The spectral distribution of the intensity of the electromagnetic field is modeled to have been reflected by a plurality of spatially well defined part-surfaces of the sample surface of the sample. The electromagnetic sensitive sensor being well-defined in terms of the functional dependency between input radiation and output signal and the registering exposure time-period being selected individually for each individual sensor element, such as to compile an information volume that represents the registered high dynamic range spectrally resolved electromagnetic radiance as a function of the position of the part-surfaces within the sample surface of the sample and of the respective angle enforced on the sample while measuring.
Abstract:
A method of obtaining high dynamic range, spectrally, spatially and angularly resolved radiance of a sample surface of a sample by an electromagnetic irradiator irradiating electromagnetic radiation of controlled spectral distribution onto the sample surface and, using an electromagnetic sensitive sensor to register the reflected spectral distribution. The spectral distribution of the intensity of the electromagnetic field is modeled to have been reflected by a plurality of spatially well defined part-surfaces of the sample surface. The electromagnetic sensitive sensor being well-defined in terms of the functional dependency between input radiation and output signal and the registering exposure time-period being selected individually for each individual sensor element, such as to compile an information volume that represents the registered high dynamic range spectrally resolved electromagnetic radiance as a function of the position of the part-surfaces within the sample surface and of the respective angle enforced on the sample while measuring.
Abstract:
A method and apparatus for obtaining a basis on which the gloss quality of a sample surface of a sample, such as a paper sheet, can be determined by illuminating the sample surface and registering the intensity of the reflected light. With the intention of enabling several different types of gloss variation investigations to be made on a sample surface essentially in accordance with known principles of gloss facet approximation, it is proposed, among other things, that the sample surface is exposed in an image registering area by controlled rotary movement of the sample surface through the image registering area or by controlled rotary movement of the image registering area over the sample surface, wherein the intensity of the light reflected from a plurality of spatially well defined part-surfaces of the sample surface is registered several time during this rotary movement while, at the same time, determining the positions of the part-surfaces in the image registering area, and in turn the viewing angle, so as to establish what we here define as an image volume which is representative of the registered light intensity as a function of the position of the part-surfaces within the sample surface and of the respective viewing angle.