Stereoscopic flat panel display with synchronized backlight, polarization control panel, and liquid crystal display
View Patent ↗An enhanced liquid crystal display design is provided having relatively fast response time particularly useful in high speed or highly intense applications, such as stereoscopic or autostereoscopic image display. The liquid crystal display device is configured to display stereoscopic images, and comprises an LCD panel and control electronics configured to drive the LCD panel to a desired 10 stereoscopic display state. The control electronics are configured to employ transient phase switching and overdrive the LCD panel to a desired state to enable relatively rapid display of stereoscopic images.
1. A method of displaying stereoscopic imagery on a flat panel display, the display having a spatially controllable backlight with a plurality of illuminating portions operable to selectively provide light to a liquid crystal (LC) modulation panel having modulation regions, and a polarization control panel (PCP) having a plurality of polarization control segments associated with the modulation regions, the polarization control segments being operable to receive modulated light from the modulation regions of the LC modulation panel and to selectively transform the state of polarization (SOP) of the modulated light incident from the modulation regions, the method comprising:
addressing data lines in a selected modulation region on the LC modulation panel with left eye image data; and
providing, at least after addressing a first data line of the selected modulation region, polarization control instructions to a polarization control segment associated with the selected modulation region, to operate in a left eye polarization display mode when a portion of the data lines in the selected modulation region display a portion of a left eye image frame;
providing the light to the selected modulation region from one or more selected illuminating portions during the left eye polarization display mode;
wherein the polarization control segment is operable to output light of a first polarization state after a first transition period.
2. The method of claim 1 , wherein the portion of the data lines in the modulation region comprises an amount in the range of 40% to 60% of the data lines in the modulation region that have settled.
3. The method of claim 1 , wherein the portion of the data lines in the selected modulation region comprises substantially half of the data lines in the selected modulation region.
4. The method of claim 1 , wherein providing polarization control instructions occurs after addressing a first data line of the selected modulation region.
5. The method of claim 1 , further comprising:
switching the polarization control segment to operate in the left eye polarization display mode; and
maintaining the SOP transformation for the polarization control segment until the polarization control segment is switched to the right eye polarization display mode.
6. The method of claim 1 , wherein an entire left eye image frame or right eye image frame is addressed within 1/120 second.
7. The method of claim 1 , wherein a settling time of the LC modulation panel for a middle data line of the selected modulation region and a second settling time of the PCP for the associated polarization control segment are optimized for negligible left and right eye cross-talk when viewing the stereoscopic imagery through left and right eye analyzers.
8. The method of claim 1 , wherein each polarization control segment comprises a zero twist LC zero to half-wave retardation modulator oriented at 45 degrees to an output polarization direction; and a quarter wave retarder oriented at 45 degrees relative to the orientation of the zero twist LC modulator.
9. The method of claim 8 , wherein the left eye polarization control instructions operate to cause the zero twist LC modulator to retard light modulated by the LC modulation panel by a half wave, and wherein right eye polarization control instructions operate to cause the zero twist LC modulator to not retard light modulated by the LC modulation panel.
10. The method of claim 8 , wherein right eye instructions operate to cause the zero twist LC to retard light modulated by the LC modulation panel by a half wave, and wherein the left eye instructions operate to cause the zero twist LC to not retard light modulated by the LC modulation panel.
11. The method of claim 1 , wherein adjacent segmented polarization control segments are sequentially scrolled on the PCP.
12. The method of claim 1 , wherein the PCP comprises strips of polarization switches operable to output incoming light to switch between orthogonal polarization states according to the polarization control instructions.
13. A flat panel display operable to display stereoscopic imagery, comprising:
a spatially controllable backlight with a plurality of illuminating portions operable to selectively provide light;
a liquid crystal (LC) modulation panel having modulation regions; and
a polarization control panel (PCP) having a plurality of polarization control segments associated with the modulation regions, the polarization control segments being operable to receive modulated light from the modulation regions of the LC modulation panel and to selectively transform the state of polarization (SOP) of the modulated light incident from the modulation regions;
wherein a selected modulation region is addressed with left eye image data, and
wherein, at least after a first data line of the selected modulation region is addressed, polarization control instructions are provided to a polarization control segment associated with the selected modulation region to operate in a left eye polarization display mode when a portion of the data lines in the selected modulation region display a portion of a left eye image frame,
wherein light is provided to the selected modulation region from one or more selected illuminating portions during the left eye polarization display mode; and
wherein the polarization control segment is operable to output light of a first polarization state after a first transition period.
14. The panel of claim 13 , wherein the PCP comprises a pi-cell.
15. The panel of claim 13 , wherein the predetermined portion of the data lines in the modulation region comprises an amount in the range of 40% to 60% of the data lines in the modulation region that have settled.
16. The panel of claim 13 , wherein the portion of the data lines in the selected modulation region comprises substantially half of the data lines in the selected modulation region.
17. The panel of claim 13 , wherein the polarization control instructions are provided after addressing a first data line of the selected modulation region.
18. The panel of claim 13 , wherein an entire left eye image frame or right eye image frame is addressed within 1/120 second.
19. The panel of claim 13 , wherein a settling time of the LC modulation panel for a middle data line of the selected modulation region and a second settling time of the PCP for the associated polarization control segment are optimized for negligible left and right eye cross-talk when viewing the stereoscopic imagery through left and right eye analyzers.
20. The panel of claim 13 , wherein each polarization control segment comprises a zero twist LC zero to half-wave retardation modulator oriented at 45 degrees to an output polarization direction; and a quarter wave retarder oriented at 45 degrees relative to the orientation of the zero twist LC modulator.
21. The panel of claim 13 , wherein the left eye polarization control instructions operate to cause the zero twist LC modulator to retard light modulated by the LC modulation panel by a half wave, and wherein right eye polarization control instructions operate to cause the zero twist LC modulator to not retard light modulated by the LC modulation panel.
22. The panel of claim 13 , wherein right eye instructions operate to cause the zero twist LC to retard light modulated by the LC modulation panel by a half wave, and wherein the left eye instructions operate to cause the zero twist LC to not retard light modulated by the LC modulation panel.
23. The panel of claim 13 , wherein adjacent segmented polarization control segments are sequentially scrolled on the PCP.
24. The panel of claim 13 , wherein the PCP comprises strips of polarization switches operable to output incoming light to switch between orthogonal polarization states according to the polarization control instructions.
25. The panel of claim 13 , wherein the polarization control segments are switched to operate in the left eye polarization display mode and the SOP transformation is maintained for the polarization control segment until the polarization control segment is switched to the right eye polarization display mode.