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Pushbroom hyperspectral imaging systems require relative motion with respect to the target for hyperspectral data acquisition by means of spatial scanning, which increases the equipment cost and limits the application scenarios. We address this by introducing a pushbroom system with an internal line-scanning unit consisting of a slit aperture mounted on a piezoelectric linear motor. Different slit positions have tilted incidence angles at the grating, resulting in shifts of diffraction patterns relative to the imaging sensor. We demonstrate a method to compensate this shift by using a rotating arm controlled by a stepper motor to reposition the camera based on slit position.

Micro- and nanostructures enable specific optical functionalities, which rely on diffractive effects or effective medium features, depending on pattern dimension and wavelength. Performance predictions of optical systems which make use of nanostructured materials require having an accurate description of these materials ready to hand within the optical design. At the one hand, nanostructure characteristics which result from rigorous electromagnetic modeling can be used for the optical design. At the other hand, manufactured nanostructures may deviate from their idealized geometry, which will affect the performance of the optical system, wherein these artificial structures will be used. Thus, detailed optical characterization of the micro- or nanostructure functionality is prerequisite for accurate optical design and performance prediction. To this end, several characterization techniques can be applied depending on the scope of the optical design, finally. We report on a general route to include all accessible and required optical information about the nanostructured material within a corresponding model of the nanostructure as a specific optical component which can be used within a ray-trace engine, finally. This is illustrated by a meta-material with asymmetric transmission properties in some more detail.