Display device including signal processor that superimposes visible light communication signals on backlight control signals generated based on an image signal

Abstract

A display device includes: a display panel including a display screen; a backlight having a light emission surface that illuminates the display screen of the display panel from behind; a second processor that superimposes the visible light communication signals on backlight control signals generated based on the image signal; and a second controller that divides the light emission surface of the backlight into regions and establishes a period during which control of light emission in each of the regions and control for turning off the backlight in each of the regions a different time are performed based on the backlight control signals outputted by the second processor. When superimposing the visible light communication signals on the backlight control signals, the second processor does not superimpose a visible light communication signal in a period indicating an OFF state of the backlight in the backlight control signals.

1 - 5 . (canceled) 
     
     
         6 . A display device that outputs visible light communication signals, the display device comprising:
 a display panel including a display screen on which an image is displayed;   a display controller that causes the display panel to display an image on the display screen of the display panel based on an image signal;   a backlight having a light emission surface that illuminates the display screen of the display panel from behind;   a signal processor that superimposes the visible light communication signals on backlight control signals generated based on the image signal; and   a backlight controller that divides the light emission surface of the backlight into regions and establishes a period during which control of light emission in each of the regions and control for turning off the backlight in each of the regions a different time are performed based on the backlight control signals outputted by the signal processor, wherein   when superimposing the visible light communication signals on the backlight control signals, the signal processor does not superimpose a visible light communication signal in a period indicating an OFF state of the backlight in the backlight control signals,   the signal processor superimposes the visible light communication signals on the backlight control signals corresponding to groups of neighboring regions among the regions,   the visible light communication signals superimposed on the backlight control signals in the same group are in phase with one another, and   for each group, corresponding visible light communication signals are superimposed in entirety in a period during which control of light emission of the backlight based on the backlight control signals corresponding to the groups is performed.   
     
     
         7 . The display device according to  claim 6 , wherein
 based on the backlight control signal corresponding to a predetermined region among the groups, the signal processor matches phases of the visible light communication signals superimposed on the backlight control signals corresponding to the groups.   
     
     
         8 . The display device according to  claim 6 , wherein
 the predetermined region is a brightest region among the regions.   
     
     
         9 . The display device according to  claim 6 , wherein
 among the visible light communication signals superimposed on the backlight control signal phases corresponding to the groups, a visible light communication signal superimposed on a backlight control signal corresponding to a first group among the groups and a visible light communication signal superimposed on a backlight control signal corresponding to a second group among the groups are out of phase.   
     
     
         10 - 20 . (canceled)