Extracting the “internally waveguided” light from OLEDs, which together with losses to plasmons at the metal cathode typically account for > 50% of the light generated in the emission zone, has proven to be a particularly challenging problem. To address this problem, we fabricated devices on nano-patterned plastic substrates that disrupt the internal waveguiding. We describe thermally evaporated small molecule fluorescent and phosphorescent OLEDs fabricated on corrugated polycarbonate (PC) and polyethylene terephthalate (PET) substrates nanopatterned in a roll-to-roll process. We compare the devices fabricated on plastic/ITO to those on plastic/PEDOT:PSS and the effect of adding a µm-scale Cu honeycomb mesh to the integrated substrate/anode as well. Depending on the height and pitch of the pattern, up to a 2.5 fold increase in the outcoupling factor is observed relative to the flat substrate. Issues related to the fidelity of the conformal deposition of the various layers on the patterned plastic are also discussed, particularly the effect of the nanopatterns on device stability.
We describe a new iteration of the StereoJet process, which has been simplified by changes in materials and improved by
the conversion from linear to circular polarization. A prototype StereoJet process for producing full color stereoscopic
images, described several years ago by Scarpetti et al., was developed at the Rowland Institute for Science, now part of
Harvard University. The system was based on the inkjet application of inks comprising dichroic dyes to Polaroid
Vectograph sheet, a concept explored earlier by Walworth and Chiulli at the Polaroid Research Laboratories. Vectograph
sheet comprised two oppositely oriented layers of stretched polyvinyl alcohol (PVA) laminated to opposite surfaces of a
cellulose triacetate support sheet. The two PVA layers were oriented at +45 and -45 degrees, respectively, with respect to
the running edge of the support sheet. A left-eye and right-eye stereoscopic image pair were printed sequentially on the
respective surfaces, and the resulting stereoscopic image viewed with conventional linearly polarized glasses having +45
and -45 degree orientation. StereoJet, Inc. has developed new, simplified technology based on the use of PVA substrate
of the type used in sheet polarizer manufacture with orientation parallel to the running edge of the support. Left- and
right-eye images are printed at 0 and 90 degrees, then laminated in register. Addition of a thin layer of 1/4-wave retarder
to the front surface converts the image pair's respective orientations to right- and left-circular polarization. The full color
stereoscopic images are viewed with circularly polarized glasses.
A general method for making optical media by a continuous roll process has been developed. The process can accommodate a variety of optical structures, although it has been optimized for those with smaller form factors and thin cover sheets. A test disk was used to demonstrate process capabilities and evaluate media made by this method.