Up to now, the image fidelity is improved apparently by the proposed Side-lit LBSR Stencil-FSC method, but the color breakup phenomenon is a little higher than the Direct-lit Green-based Stencil-FSC method. This is because the red and blue information of the proposed method are reduced to avoid redundant red and blue light propagating into the first field. In other words, the luminance of the second and third field-image are increased as shown in Fig. 5-3, then the separated colors contain higher luminance intensity causing the color breakup phenomenon is more serious than the Direct-lit Green-based Stencil-FSC method.
Side-lit
RGB-driving Green-based
Stencil-FSC LBSR Stencil-FSC LBSR Stencil-FSC
Panel Thickness ~ 30mm ~ 30mm ~ 30mm < 10mm
Backlight Divisions Global 24x32 24x32 2x16
(d) (e) (f)
Fig. 5-3 Three field-images of the green-based method: (a) 1st field-image, (b) 2nd field-image, and (c) 3rd field-image; three field-images of the proposed method: (d) 1st field-image, (e) 2nd field-image, and (f) 3rd field-image.
In the proposed method, the LBSR method is utilized to decide proper backlight signals of first field; the backlight signals of second and third field are calculated by the maximum transmittance of remnant red and blue information. Therefore, the future work is to further reduce color breakup phenomenon, we could use the LBSR method to put a portion of blue information in second field. Thus the second field-image contains remnant red and a portion of blue information, the luminance of third field-image is therefore reduced. Fig. 5-4 is the schematic figure which the second field is contained a portion of blue information to reduce color breakup phenomenon. As a result, the color breakup phenomenon can be suppressed due to the separated color of second field is no longer mono-color field and the separated color luminance of third field is reduced as shown in Fig. 5-4.
(a) (b) (c)
Fig. 5-4 Three field-images of schematic image, (a) 1st field-image, (b) 2nd field-image, and (c) 3rd field-image. The 2nd field contains portion of blue information and the luminance of 3rd field is reduced.
(a) (b)
Fig. 5-5 Color breakup comparison between (a) the proposed Side-lit LBSR Stencil-FSC method, and (b) the modified 2nd and 3rd field in the proposed method.
Finally, by adding portion of 3rd field information with LBSR method in 2nd field, we can further analyze different dominant color in first field and change different color sequence of field-images to achieve better color breakup suppression.
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