Dr. Hans M. Kariis Profile

Dr. Hans M. Kariis

Deputy Research Director at FOI-Swedish Defence Research Agency

SPIE Involvement:

Conference Program Committee | Author

Publications (9)

Proceedings Article | 17 October 2019

Round robin comparison of BRDF measurements

Tomas Hallberg, Daniel Pearce, Peter Raven, Christopher Baker, Richard Moore, Hans Kariis

Proc. SPIE. 11158, Target and Background Signatures V

KEYWORDS: FT-IR spectroscopy, Sensors, Calibration, Spectroscopy, Light scattering, Reflectivity, Bidirectional reflectance transmission function, Integrating spheres

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Proceedings Article | 9 October 2018

Optical polarization and the dependence of angle of incidence for different surfaces: comparison between different wavelengths from UV to IR

Tomas Hallberg, Johan Eriksson, Stefan Björkert, Hans Kariis

Proc. SPIE. 10794, Target and Background Signatures IV

KEYWORDS: Polarization, Sensors, Spectroscopy, Light scattering, Reflectivity, Polarimetry, Bidirectional reflectance transmission function, Aluminum, Integrating spheres, Thin film coatings

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Proceedings Article | 5 October 2017

Optical polarization: background and camouflage

Christina Åkerlind, Tomas Hallberg, Johan Eriksson, Hans Kariis, David Bergström

Proc. SPIE. 10432, Target and Background Signatures III

KEYWORDS: Infrared sensors, Infrared imaging, Polarization, Sensors, Polarimetry, Infrared radiation, Camouflage, Infrared signatures, Infrared technology, Sensor technology

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Proceedings Article | 24 October 2016

Camouflage in thermal IR: spectral design

Anna Pohl, Jan Fagerström, Hans Kariis, Roland Lindell, Tomas Hallberg, Herman Högström

Proc. SPIE. 9997, Target and Background Signatures II

KEYWORDS: Defense and security, Thermography, Cameras, Coating, Reflectivity, Black bodies, Infrared radiation, Aluminum, Camouflage, Temperature metrology

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Proceedings Article | 21 October 2015

A systems approach to stealth on the ground revisited

Kent Andersson, Hans Kariis, Gunnar Hult

Proc. SPIE. 9653, Target and Background Signatures

KEYWORDS: Target detection, Radar, Defense and security, Weapons, Sensors, Bidirectional reflectance transmission function, Camouflage, Infrared signatures, Systems engineering, Systems modeling

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Proceedings Article | 21 October 2015

Evaluation criteria for spectral design of camouflage

Christina Åkerlind, Jan Fagerström, Tomas Hallberg, Hans Kariis

Proc. SPIE. 9653, Target and Background Signatures

KEYWORDS: Long wavelength infrared, Near infrared, Polarization, Sensors, Metals, Reflectivity, Bidirectional reflectance transmission function, Surface properties, Aluminum, Camouflage

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In development of visual (VIS) and infrared (IR) camouflage for signature management, the aim is the design of surface properties of an object to spectrally match or adapt to a background and thereby minimizing the contrast perceived by a threatening sensor. The so called 'ladder model" relates the requirements for task measure of effectiveness with surface structure properties through the steps signature effectiveness and object signature. It is intended to link materials properties via platform signature to military utility and vice versa. Spectral design of a surface intends to give it a desired wavelength dependent optical response to fit a specific application of interest. Six evaluation criteria were stated, with the aim to aid the process to put requirement on camouflage and for evaluation. The six criteria correspond to properties such as reflectance, gloss, emissivity, and degree of polarization as well as dynamic properties, and broadband or multispectral properties. These criteria have previously been exemplified on different kinds of materials and investigated separately. Anderson and Åkerlind further point out that the six criteria rarely were considered or described all together in one and same publication previously. The specific level of requirement of the different properties must be specified individually for each specific situation and environment to minimize the contrast between target and a background. The criteria or properties are not totally independent of one another. How they are correlated is part of the theme of this paper. However, prioritization has been made due to the limit of space. Therefore all of the interconnections between the six criteria will not be considered in the work of this report. The ladder step previous to digging into the different material composition possibilities and choice of suitable materials and structures (not covered here), includes the object signature and decision of what the spectral response should be, when intended for a specific environment. The chosen spectral response should give a low detection probability (DP). How detection probability connects to image analysis tools and implementation of the six criteria is part of this work.