Thermal sensing metasurface with programmable wave-front manipulation.

Combining thermal field sensing with microwave manipulation has always been a widely pursued topic for metamaterials for some time. However, most temperature-sensitive designs for metamaterials and metasurfaces are still limited in the single absorption manipulation. In this paper, we present a metasurface with programmable wave-front modulation for distributed thermal sensing. An element integrated with a Positive-Intrinsic-Negative (PIN) diode was designed for 1-bit phase response control, while a column of thermistors was applied for the distributed thermal stimulus. When the thermistors in distinct positions sensed the heat, a voltage control circuit directly changed the on-off states of diodes, to generate specific scattering fields. To demonstrate this behavior, a metasurface sample with 25 × 27 elements was designed, fabricated, and measured using four patterns. The results show great consistency with the simulation data, thereby validating the design. [ABSTRACT FROM AUTHOR]