Intrinsic coincident full-Stokes polarimeter using stacked organic photovoltaics

Abstract

An intrinsic coincident full-Stokes polarimeter is demonstrated by using strain-aligned polymer-based organic photovoltaics (OPVs) that can preferentially absorb certain polarized states of incident light. The photovoltaic-based polarimeter is capable of measuring four Stokes parameters by cascading four semitransparent OPVs in series along the same optical axis. This in-line polarimeter concept potentially ensures high temporal and spatial resolution with higher radiometric efficiency as compared to the existing polarimeter architecture. Two wave plates were incorporated into the system to modulate the S₃ Stokes parameter so as to reduce the condition number of the measurement matrix and maximize the measured signal-to-noise ratio. Radiometric calibration was carried out to determine the measurement matrix. The polarimeter presented in this paper demonstrated an average RMS error of 0.84% for reconstructed Stokes vectors after normalized to S₀. A theoretical analysis of the minimum condition number of the four-cell OPV design showed that for individually optimized OPV cells, a condition number of 2.4 is possible.

Panchromatic All‐Polymer Photodetector with Tunable Polarization Sensitivity

“…This feature can be exploited to achieve photodetectors that are polarization sensitive without the need of additional light‐manipulating optics. This reduced complexity simplifies polarization‐sensitive devices, and opens up new opportunities in detector architectures such as polarized detectors in tandem to realize compact coincident polarimeters (polarization state detectors) …”

“…Thus, orienting the polymer backbone in a film results in anisotropic optical and electrical properties . This unique property of polymer semiconductors has been exploited to achieve polarized light‐emitting diodes and polarized photovoltaics . There have been numerous processes to achieve oriented films that include alignment during solution processing, or post solidification film manipulation .…”

“…This unique property of polymer semiconductors has been exploited to achieve polarized light‐emitting diodes and polarized photovoltaics . There have been numerous processes to achieve oriented films that include alignment during solution processing, or post solidification film manipulation . One common approach is to apply an external mechanical load to a cast film by physically rubbing or uniaxial stretching .…”

“…There have been numerous processes to achieve oriented films that include alignment during solution processing, or post solidification film manipulation . One common approach is to apply an external mechanical load to a cast film by physically rubbing or uniaxial stretching . An advantage of these two techniques is the ability to tune the magnitude of polymer alignment that in turn dictates polarization sensitivity, which is important in optimizing the performance of polarimeters .…”

“…One common approach is to apply an external mechanical load to a cast film by physically rubbing or uniaxial stretching . An advantage of these two techniques is the ability to tune the magnitude of polymer alignment that in turn dictates polarization sensitivity, which is important in optimizing the performance of polarimeters . Although rubbing has been demonstrated to produce films with significant diattenuation, the method can lead to uneven surfaces that may result in devices prone to shorting .…”