Mohammadi Elham, Behdad Nader
University of Wisconsin-Madison, Department of Electrical and Computer Engineering, Madison, WI, 53706, USA.
Sci Rep. 2017 Dec 12;7(1):17475. doi: 10.1038/s41598-017-17675-6.
We present the design, fabrication, and characterization of an infrared (IR) polarization sensing detector with a wide dynamic range and sub-wavelength dimensions. The detector consists of two orthogonal slot antennas, each loaded with two microbolometers at its edges. The polarization of the incoming IR radiation is detected by comparing the received power levels in the bolometer pairs corresponding to each slot antenna. The IR radiation is sensed by applying a dc bias voltage to each antenna and measuring the changes in the dc current caused by the change of the bolometer resistance as they absorb the incoming IR radiation. In this design, the ratio of the absorbed power in the bolometers is a one to one function of the polarization of the incident wave. A prototype of this detector, designed to have maximum sensitivity at λ = 10.6 μm, was designed, fabricated, and characterized. The fabricated detector has an area of 0.7λ × 0.7λ, where λ is the free-space wavelength. The polarization sensing response is characterized under different angles of incidence. The measurement results show that the device has a dynamic range of 24 dB between two orthogonal orientations of EM wave polarization for incidence angles in the range of ±20° from boresight.
我们展示了一种具有宽动态范围和亚波长尺寸的红外（IR）偏振传感探测器的设计、制造和特性。该探测器由两个正交的缝隙天线组成，每个天线在其边缘加载有两个微测辐射热计。通过比较与每个缝隙天线对应的微测辐射热计对中的接收功率水平，来检测入射红外辐射的偏振。通过向每个天线施加直流偏置电压，并测量由于微测辐射热计吸收入射红外辐射时电阻变化而引起的直流电流变化，来感测红外辐射。在这种设计中，微测辐射热计中吸收功率的比值是入射波偏振的一对一函数。设计、制造并表征了该探测器的一个原型，其设计目的是在λ = 10.6μm时具有最大灵敏度。制造的探测器面积为0.7λ×0.7λ，其中λ是自由空间波长。在不同入射角下对偏振传感响应进行了表征。测量结果表明，对于偏离视轴±20°范围内的入射角，该器件在电磁波偏振的两个正交方向之间的动态范围为24dB。
