## 4 Discussion  
A time-sequential working spatially-multiplexed autostereoscopic 3D display concept consisting of a fast switchable RGB-color filter array could be presented. The assembling of such a large array with wavelength-selective filters used as the image splitter barrier has been simulated in interaction with a color display matrix. As an outstanding result, such a barrier emits the light from a display over a larger active area than common autostereoscopic barrier displays. The separation of equally-colored subpixel columns, which are separated by two differently-colored columns, produces in the simulation excellent crosstalk suppression. According to progress in the project, no large-scaled sample of the described switchable color barriers was available for the experimental verification of the arrangement. For that reason, commercial display components had to be used. Because of the low switching speed of these components and the non-synchrony address directions (one display is 90\({}^{\circ}\) rotated), the measurements and correspondingly the simulations of this system were carried out on static switching states. The search for suitable components yielded only a single display combination that fulfilled the requirements for suitable resolutions, pixel pitches and polarizer alignment. The color subpixels of both of these display components are small and exhibit unfavorable geometric and optical properties, which greatly reduce the brightness and cause an inadmissible crosstalk. Both components have been combined in a mock-up by replacing the backlight of the barrier display in front of the assembly. Using a green test pattern, it could be shown on the display mock-up that the introduced assembling of the display and color barrier array creates an autostereoscopic display image in every switching state. The documentation and analysis of the image properties was only possible by means of optical measurement technology. The influence of the gaps in display cells and in the barrier stripes was detected and examined with the help of the simulation. It was not possible to separate the kinds of crosstalk at the measurements of the demonstrator. However, the influence of electrical and optical crosstalk could be simulated with a simulation approach. In that way, it was possible to reproduce the luminance curve sufficiently well, due to the used parameters with different influences on the luminance curve. The causes of the crosstalk (optical & electrical) in the static image could thus be assigned unambiguously by the simulation. The temporal superimposition of the 3D representations generated in the successive switching stages led to the desired resolution improvement. Dynamic switching processes in the display and barrier increase the optical crosstalk. Further research is necessary to take this into consideration in the simulation. However, the hitherto performed investigations show that time-sequential wavelength-separated 3D displays need special designs of the LC-matrix, which strongly reduce the electrical crosstalk. The traditional color filter cells used for commercial nematic displays have inadmissibly high optical leakages and an insufficient switching speed for their application in time-sequential wavelength-selective autostereoscopic displays. Therefore, other, extremely fast switchable filter designs with excellent color separation have to be used in the display and barrier. In this paper, we present a design concept of a fast tunable NLC Fabry-Perot interference filter cell operating in the visible range. It consists of a sub-micrometer-thick NLC layer embedded in a matched filter design. An experimental proof of the feasibility of NLC Fabry-Perot filters for the construction of the millisecond regime tunable color filters is given. Reducing the cavity thickness of the NLC Fabry-Perot filter to the sub-micrometer region improved the switching times, and an extension of the FSR in the visible range was achieved. The usable operation range of the presented filters amounts to about 30 nm.