Chapter 6 Conclusions and Future work
6.2 Future Work
The proposed Stencil-FSC method is a color sequence with four fields.
Optimization works have been done in the thesis to verify effective CBU suppression on the FSC-LCD. However, if the Stencil-FSC method is simplified to a three-field color sequence, it will make the Stencil-FSC method perform much better or easier to be installed on the real panel. As mentioned in section 2.2, increasing the field rate and reducing the frame duty can narrow CBU causing viewers to be less sensitive to CBU, which is helpful for CBU suppression. For example, the field rate of the Stencil-FSC four-field method is 240Hz. If the field rate is applied on the Stencil-FSC three-field method, the frame rate will be 80Hz, thus can suppress CBU more effectively. On the other hand, if the frame rate is maintain at the typical frequency, 60Hz, the field rate of the Stencil-FSC three-field method will be 180Hz, and the field duty will be longer compared to it with four fields. Therefore, it will take more time to achieve LC response and data addressing, so the panel structure can be simplified.
Consequently, the Stencil-FSC three-field method is more attractive for commercial applications, and its concept is introduced as following:
The three-field color sequence is based on the proposed Stencil-FSC method, and its first field also uses the first multi-color field of the Stencil-FSC method. Because the multi-color field is composed by the minimum value of compensated LC signal and colorful locally controlled backlight as mentioned in 3.1.3, it will display the base color image, and at least one color of red, green, and blue will be correct as shown in Fig. 6-1(b). Therefore, at least one of the three primary colors in the remnant image gotten from the subtraction between the target image and multi-color field equals zero, as in Fig. 6-1(c), so two multi-color fields will be utilized to display the remnant image of the two primary colors as shown in Fig. 6-1(d). Finally, a full-color image
can be displayed by the Stencil-FSC three-field method, as in Fig. 6-2.
However, the algorithm has two issues which need to be overcome in the future.
First, the algorithm is strongly dependent on the number of backlight divisions, and a larger number of backlight divisions is needed to achieve acceptable image performance, as in Fig. 6-3. However, large number of backlight sub-regions will cause complicated hardware and decrease the production feasibility. Therefore, an optimized algorithm is needed to be presented to overcome this issue. The second issue is that there are three different locally controlled color backlight distribution in the method, so the process of backlight distribution generation is three times complex compared it to the Stencil-FSC four-field method. Thus, simplifying the processes of three different backlights distribution is the other work needed to be done in the future.
Finally, by utilizing the Stencil-FSC three-field method and overcoming the mentioned issues in the future, the Stencil-FSC method can suppress CBU more effectively and can be much more applicable for display technology.
(a) (b)
(c) (d)
Fig. 6-1 The concept of the Stencil-FSC three-field method. (a) Target image, (b) first multi-color field of the Stencil-FSC method, (c) the remnant image, and (d) two multi-color-fields to display the remnant image.
Fig. 6-2 Stencil-FSC three-field method
(a)
(b)
(c)
Fig. 6-3 (a) Target image, (b) the Stencil-FSC three-field image and the number of backlight sub-regions equal 32*32, and (c) the Stencil-FSC three-field image with three fields and the number of backlight sub-regions equal 64*64
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