Given the achieved EQE improvements, we explored applications to demonstrate the practical use of this new device architecture. Due to the contrasting UC performance between samples with and without TCA upon NIR excitation and the potential to pattern the TCA layer, anti-counterfeiting was particularly attractive to us. We found that the thermal deposition of TCA (~12 nm) shows the same improvements as we observed via solution-processing. We patterned the TCA layer using a shadow mask (see Figure ) followed by rubrene/DBP evaporation on the entire substrate (i.e., without a mask). Upon NIR excitation, we observed a strong contrast between TCA-and non-TCA-patterned areas.