A novel channel-modulated static birefringent Fourier transform imaging spectropolarimeter (CSBFTIS) is introduced, which is based on a double Wollaston prism (DWP). With an adjustable air gap (AG), the spectral resolution can be adjusted by changing the AG. The CSBFTIS combines the channel-modulated imaging spectropolarimeter and the slit-free static birefringent Fourier transform imaging spectrometer technology with adjustable spectral resolution. The device is compact and robust, with a wide spectral range and a large luminous flux. Compared with various previous spectropolarimeters, it can greatly reduce the size of the spectral image data to adapt to different application requirements. A prototype is built, and simulation and experiments are carried out, and the results prove the effectiveness of the method.

The optical displacement calculation formula for the dual Wollaston prism is derived for any incident plane and angle using the wave normal tracing method. The validity of the calculation is confirmed by comparing it with captured photographs. The relationship between the maximum incident aperture, incident angle, and incident surface angle is given when plane and spherical waves incident on the prism group. The aperture utilization of a novel static birefringent Fourier transform imaging spectrometer based on dual Wollaston prisms is also analyzed. The relationship of aperture utilization with the incident surface angle, incident angle, and prisms’ air gap thickness is given. The results provide a theoretical foundation for fully describing the optical transmission characteristics of the dual Wollaston prism group and developing a high-performance spatio-tempo hybrid modulated birefringent spectral zoom Fourier transform imaging spectrometer.

Plasmonic nanostructures offer a practical solution for solar-to-thermal conversion, yet simultaneously achieving ultra-broadband absorption, scalable fabrication, and long-term stability using earth-abundant aluminum remains difficult. In this work, we present a three-dimensional (3D) crown-like aluminum nanostructure absorber that achieves an experimental average absorption of 92% across the solar spectrum (200–2500 nm), with only 1.9% degradation in average absorption over 24 months. The structure is fabricated via a scalable anodic aluminum oxide (AAO) template-assisted method, enabling large-area production without costly lithography and exhibiting broad fabrication tolerance to deposition-thickness variations. Electromagnetic simulations and structure analysis reveal that the ultra-broadband absorption arises from three synergistic mechanisms: multi-mode electric resonances, magnetic resonance behavior within the metal–dielectric–metal architecture, and a graded-refractive-index profile. Proof-of-concept photothermal experiments under simulated sunlight offer experimental confirmation of the absorber’s solar-to-thermal conversion capability, showing substantially enhanced solar-to-thermal energy utilization compared to pure-water references. This work provides a scalable, durable, and cost-effective platform for ultra-broadband solar absorption and solar-to-thermal conversion, and offers a viable design strategy for plasmonic absorbers based on earth-abundant materials.