Wide Dynamic Range, Angle-Sensing, Long-Wave Infrared Detector Using Nano-Antenna Arrays

Area of Science:

• Optoelectronics
• Infrared Technology
• Antenna Design

Background:

• Accurate angle detection is critical for infrared systems.
• Existing methods may have limitations in sensitivity or size.
• Long-wave infrared (LWIR) detection requires specialized antenna designs.

Purpose of the Study:

• To present a new technique for designing angle-sensing LWIR detectors.
• To demonstrate a compact detector with subwavelength dimensions.
• To achieve precise angle-of-arrival determination for LWIR signals.

Main Methods:

• Utilizing two closely-spaced, directive infrared antennas (Yagi-Uda arrays) for angle detection.
• Optimizing antenna structures to function as both energy collectors and distributed bolometers.
• Measuring the ratio of absorbed power (via resistance change) in the antennas to determine signal angle.

Main Results:

• Fabrication and measurement of an angle-sensing detector for λ = 10.6 μm.
• Achieved subwavelength dimensions of approximately 0.6 λ₀ × 0.4 λ₀.
• Demonstrated an angle sensing dynamic range of 22 dB over a ±60° field of view.

Conclusions:

• The proposed Yagi-Uda antenna-bolometer design enables effective LWIR angle sensing.
• The compact, subwavelength detector offers a significant advancement in infrared sensing capabilities.
• This technique provides a robust method for determining the angle of arrival of LWIR signals.