Thermal resolution enhancements using a focusing element

An apparatus that disperses long-wave infra-red (LWIR) light having wavelengths spanning from about 8 microns to about 14 microns into a plurality of sub-wavebands via use of a flat-surfaced focusing element that (i) has a low profile z-height, (ii) has lenslets that are substantially immediately proximate to one another, and (iii) operates on the LWIR light in a spatial and spectral manner, said apparatus comprising:

• a filter array, which includes a plurality of optical bandpass filters arranged in a pattern, wherein:
• each optical bandpass filter in the filter array is structured to spectrally split the LWIR light into a corresponding sub-waveband,
• a combination of each corresponding sub-waveband forms the plurality of sub-wavebands, and
• the plurality of sub-wavebands covers at least half of the wavelengths of the LWIR light;
• and
• the flat-surfaced focusing element, which includes a meta-lens comprising a plurality of lenslets also arranged in the pattern and which is aligned with the filter array such that each optical bandpass filter in the filter array is aligned with a corresponding lenslet in the plurality of lenslets, wherein:
• each lenslet in the plurality of lenslets is structured to include a corresponding array of pillars, and
• each array of pillars of each lenslet creates a corresponding point spread function that spatially delays a phase of the LWIR light, resulting in each lenslet generating a focused beam of a corresponding portion of the LWIR light.

An apparatus that spatially and spectrally disperses long-wave infra-red (LWIR) light into a plurality of sub-wavebands, said apparatus comprising:

• a thermal imaging sensor;
• a filter array, which includes a plurality of optical bandpass filters arranged in a pattern, wherein:
• each optical bandpass filter in the filter array is structured to spectrally split the LWIR light into a corresponding sub-waveband to form the plurality of sub-wavebands, each optical bandpass filter in the filter array is spatially positioned proximate to at least two other optical bandpass filters in the filter array;
• and
• a meta-lens, which includes a plurality of lenslets also arranged in the pattern and which is aligned with the filter array such that each optical bandpass filter in the filter array is aligned with a corresponding lenslet in the plurality of lenslets, wherein:
• each lenslet in the plurality of lenslets is structured to include a corresponding array of pillars, and
• each array of pillars of each lenslet creates a corresponding point spread function that spatially delays a phase of the LWIR light, resulting in each lenslet focusing a corresponding portion of the LWIR light onto a corresponding set of pixels of the thermal imaging sensor.