DON26BZ01-NV011 — Compact Battery Operated Mid-wave Infrared (MWIR) Hyperspectral, High-Definition, Real-Time Video Camera Integrated with Photonic Crystal

Award Maximum: $140,000 (Base) / $100,000 (Option) Period of Performance: 6 months (Base) + 6 months (Option) Phase Type: Phase I

OBJECTIVE: Develop and demonstrate a compact battery-operated mid-wave infrared (MWIR) hyperspectral imaging (HSI) photonic chip video camera for integration into mobile network enabled small sensor platforms.

DESCRIPTION: Hyperspectral imaging allows quantitative evaluation of material composition and spatial distribution and finds numerous applications in areas such as remote sensing and military reconnaissance. In particular, the operational utility of HSI for detection, recognition and identification of hard-to-detect targets in environments cluttered with background noise is especially critical. Spectral imaging can aid the detection, acquisition and tracking of a potentially camouflaged, low-signature target, with significantly improved accuracy that cannot otherwise be detected using more conventional imaging means.

Conventional HSI systems tend to use large, bulky optical elements, such as a Michelson interferometer or other tunable optical filter components to spectrally resolve the input optical signals, and therefore usually have the characteristics of significant size, weight, and power (SWaP) consumption, mechanical complexity, as well as non-compliance with military specifications. More importantly, the mechanical mechanism of the conventional tunable filtering system gives rise to extremely slow spectral scanning speed and thus, slow imaging speed at that rate of one hyperspectral image per approximately one to two minutes.

It is therefore the objective of this SBIR topic to develop a battery-operated, compact, high-performance MWIR HSI camera system capable of capturing HSI video at real-time or higher frame rates in the room temperature thermal infrared region.

System required parameters include: (1) Wavelength range: 3-5 microns; (2) Array size: Threshold — 1280 x 1024 pixels; Objective — 2048 x 1536 pixels; (3) Spectral resolution: below 5 nm; (4) Pixel pitch: Threshold – 12 microns; Objective – 8 microns; (5) Real-time hyperspectral video imaging Programmable; 0.0015 Hz to 125 Hz frames per second; (6) Acquisition time of hyperspectral image with 500 spectral bands: < 40 ms or minimum 25 video data cubes (each with 500 spectral bands) per second; (7) Size and Weight: 7.5 grams and < 4.9 cm³; (8) Battery Type: Lithium-ion battery enhanced by using carbon-based nanostructures with a specific energy > 600 Wh/kg at 0.5C discharge rate, and specific capacity of > 600 Ah/kg; (9) Low power consumption, starting at 600 mW; (10) Humidity Non-condensing between 5% - 95%; (11) Non-Operating Temperature Range -57 °C to +80 °C; (12) Operating Temperature Range -40 °C to +71 °C; (13) Operational Altitude 40,000 ft; (14) Shock 40g w/ 11ms half-sine pulse, 3-axis; (15) Vibration 5.8 grms 3-axis, 1hr each.

PHASE I: Demonstrate the feasibility of using massive parallel computing to design hyperspectral photonic chips. The design should shorten the acquisition time by 100X, i.e., reducing the time from seconds in traditional HSI to a few milliseconds. It should improve the spectral resolution by 10X, i.e., going from tens of nanometers to a few nanometers, which translates into over 500 spectral bands in the MWIR band (3 to 5 um). The spatial resolution should be consistent with today's FPA resolution to reach 3.1-mega pixel for high-definition images. The design could be realized in ultra-compact form factor, reducing traditional HSI's size and weight by 10–20 times. The Phase I effort will include prototype plans to be developed under Phase II.

PHASE II: Optimize the unit cell design and lattice lengths to allow for (i) polarization insensitivity, (ii) WFOV performance, and (iii) broadband performance. Demonstrate a fully coupled design process using machine learning and physical simulation. Perform experimental verification of the generated design by demonstrating a real time MWIR hyperspectral imager with 5 nm spectral resolution, 1.3-million-pixel count, at 30 Hz frame rate. Demonstrate tunable focal lengths using lens-embedded photonic crystals.

PHASE III DUAL USE APPLICATIONS: Outputs from Phase II are anticipated to be TRL 7 but may require additional effort to refine to a more manufacturable design. Concentrate on the manufacturability as well as the fabrication process itself to prepare for commercial offerings of a fully functional product. The commercial potential includes new handheld and portable instruments for chemical, photometric, and biological sensing. Photonic crystal cameras can be integrated into compact form factors that enable in situ measurement for manufacturing process analysis and in-process feedback control. Applications include solid-state lighting characterization and testing, emissions control, portable sensing, and personal health care.

KEYWORDS: Photonic crystal; Hyperspectral; Camera; Focal plane array; On-chip; Filter