Display unit and electronic apparatus

Abstract

The invention provides a display unit that displays images on both the front and the rear surfaces and that displays images brightly without increasing the electrical power consumption. A liquid crystal display unit includes two liquid crystal cells, a backlight, which is interposed between the two liquid crystal cells and which emits light to the liquid crystal cells, and two reflective polarizers interposed between the backlight and each of the liquid crystal cells, respectively.

1 . A display device comprising: 
 a first transmissive polarization axis rotating device;    a second transmissive polarization axis rotating device having a display area size that is smaller than a display area size of the first transmissive polarization axis rotating device;    an illumination device disposed between the first transmissive polarization axis rotating device and the second transmissive polarization axis rotating device, the illumination device having a larger area in plan view than the display area of the first transmissive polarization axis rotating device, the illumination device being capable of illuminating the display area of the first transmissive polarization axis rotating device and the display area of the second transmissive polarization axis rotating device;    a light scattering layer disposed between the illumination device and the second transmissive polarization axis rotating device; and    a light shielding layer interposed between the second transmissive polarization axis rotating device and the illumination device, the light shielding layer including an opening that enables the display area of the second transmissive polarization axis rotating device to be a light transmissive region.    
   
   
       2 . The display device according to  claim 1 , the light shielding layer being disposed on both sides of the opening in cross-sectional view of the display device.  
   
   
       3 . The display device according to  claim 1 , the scattering layer being composed of a film with a roughened surface or an adhesive film with a light scattering function.  
   
   
       4 . The display device according to  claim 1 , the illumination device including: 
 a light source; and    a light guiding plate that guides light from the light source, the light guiding plate having a birefringence of about zero.    
   
   
       5 . A foldable cellular phone, comprising: 
 the display device according to  claim 1;  and    a body paired with the display device.    
   
   
       6 . An electronic device comprising the display device according to  claim 1 .  
   
   
       7 . A display device comprising: 
 a first transmissive polarization axis rotating device;    a second transmissive polarization axis rotating device having a display area size that is smaller than a display area size of the first transmissive polarization axis rotating device;    an illumination device disposed between the first transmissive polarization axis rotating device and the second transmissive polarization axis rotating device, the illumination device having a larger area in plan view than the display area of the first transmissive polarization axis rotating device, the illumination device being capable of illuminating the display area of the first transmissive polarization axis rotating device and the display area of the second transmissive polarization axis rotating device;    a light scattering layer disposed between the illumination device and the first transmissive polarization axis rotating device; and    a light shielding layer interposed between the second transmissive polarization axis rotating device and the illumination device, the light shielding layer including an opening that enables the display area of the second transmissive polarization axis rotating device to be a light transmissive region.    
   
   
       8 . The display device according to  claim 7 , the light shielding layer being disposed on both sides of the opening in cross-sectional view of the display device.  
   
   
       9 . The display device according to  claim 7 , the scattering layer being composed of a film with a roughened surface or an adhesive film with a light scattering function.  
   
   
       10 . The display device according to  claim 7 , the illumination device including: 
 a light source; and    a light guiding plate that guides light from the light source, the light guiding plate having a birefringence of about zero.    
   
   
       11 . A foldable cellular phone, comprising: 
 the display device according to  claim 7;  and    a body paired with the display device.    
   
   
       12 . An electronic device comprising the display device according to  claim 7 .  
   
   
       13 . A display device comprising: 
 a first transmissive polarization axis rotating device;    a second transmissive polarization axis rotating device having a display area size that is smaller than a display area size of the first transmissive polarization axis rotating device;    an illumination device disposed between the first transmissive polarization axis rotating device and the second transmissive polarization axis rotating device, the illumination device having a larger area in plan view than the display area of the first transmissive polarization axis rotating device, the illumination device being capable of illuminating the display area of the first transmissive polarization axis rotating device and the display area of the second transmissive polarization axis rotating device;    a first light scattering layer disposed between the illumination device and the first transmissive polarization axis rotating device;    a second light scattering layer disposed between the illumination device and the second transmissive polarization axis rotating device; and    a light shielding layer interposed between the second transmissive polarization axis rotating device and the illumination device, the light shielding layer including an opening that enables the display area of the second transmissive polarization axis rotating device to be a light transmissive region.    
   
   
       14 . The display device according to  claim 13 , the light shielding layer being disposed on both sides of the opening in cross-sectional view of the display device.  
   
   
       15 . The display device according to  claim 13 , the scattering layers being composed of a film with a roughened surface or an adhesive film with a light scattering function.  
   
   
       16 . The display device according to  claim 13 , the illumination device including: 
 a light source; and    a light guiding plate that guides light from the light source, the light guiding plate having a birefringence of about zero.    
   
   
       17 . A foldable cellular phone, comprising: 
 the display device according to  claim 13;  and    a body paired with the display device.    
   
   
       18 . An electronic device comprising the display device according to  claim 13 .  
   
   
       19 . A display device comprising: 
 a first liquid crystal panel;    a second liquid crystal panel having a display area size that is smaller than a display area size of the first liquid crystal panel;    an illumination device disposed between the first liquid crystal panel and the second liquid crystal panel, the illumination device having a larger area in plan view than the display area of the first liquid crystal panel, the illumination device being capable of illuminating the display area of the first liquid crystal panel and the display area of the second liquid crystal panel;    a light scattering layer disposed between the illumination device and the second liquid crystal panel; and    a light shielding layer interposed between the second liquid crystal panel and the illumination device, the light shielding layer including an opening that enables the display area of the second liquid crystal panel to be a light transmissive region.    
   
   
       20 . The display device according to  claim 19 , the light shielding layer being disposed on both sides of the opening in cross-sectional view of the display device.  
   
   
       21 . The display device according to  claim 19 , the scattering layer being composed of a film with a roughened surface or an adhesive film with a light scattering function.  
   
   
       22 . The display device according to  claim 19 , the illumination device including: 
 a light source; and    a light guiding plate that guides light from the light source, the light guiding plate having a birefringence of about zero.    
   
   
       23 . The display device according to  claim 19 , the illumination device including an organic EL light that emits light from two surfaces to radiate a surface of the first liquid crystal panel and a surface of the second liquid crystal panel with light.  
   
   
       24 . A foldable cellular phone, comprising: 
 the display device according to  claim 19;  and    a body paired with the display device.    
   
   
       25 . An electronic device comprising the display device according to  claim 19 .  
   
   
       26 . A display device comprising: 
 a first liquid crystal panel;    a second liquid crystal panel having a display area size that is smaller than a display area size of the first liquid crystal panel;    an illumination device disposed between the first liquid crystal panel and the second liquid crystal panel, the illumination device having a larger area in plan view than the display area of the first liquid crystal panel, the illumination device being capable of illuminating the display area of the first liquid crystal panel and the display area of the second liquid crystal panel;    a light scattering layer disposed between the illumination device and the first liquid crystal panel; and    a light shielding layer interposed between the second liquid crystal panel and the illumination device, the light shielding layer including an opening that enables the display area of the second liquid crystal panel to be a light transmissive region.    
   
   
       27 . The display device according to  claim 26 , the light shielding layer being disposed on both sides of the opening in cross-sectional view of the display device.  
   
   
       28 . The display device according to  claim 26 , the scattering layer being composed of a film with a roughened surface or an adhesive film with a light scattering function.  
   
   
       29 . The display device according to  claim 26 , the illumination device including: 
 a light source; and    a light guiding plate that guides light from the light source, the light guiding plate having a birefringence of about zero.    
   
   
       30 . The display device according to  claim 26 , the illumination device including an organic EL light that emits light from two surfaces to radiate a surface of the first liquid crystal panel and a surface of the second liquid crystal panel with light.  
   
   
       31 . A foldable cellular phone, comprising: 
 the display device according to  claim 26;  and    a body paired with the display device.    
   
   
       32 . An electronic device comprising the display device according to  claim 26 .  
   
   
       33 . A display device comprising: 
 a first liquid crystal panel;    a second liquid crystal panel having a display area size that is smaller than a display area size of the first liquid crystal panel;    an illumination device disposed between the first liquid crystal panel and the second liquid crystal panel, the illumination device having a larger area in plan view than the display area of the first liquid crystal panel, the illumination device being capable of illuminating the display area of the first liquid crystal panel and the display area of the second liquid crystal panel;    a first light scattering layer disposed between the illumination device and the first liquid crystal panel;    a second light scattering layer disposed between the illumination device and the second liquid crystal panel; and    a light shielding layer interposed between the second liquid crystal panel and the illumination device, the light shielding layer including an opening that enables the display area of the second liquid crystal panel to be a light transmissive region.    
   
   
       34 . The display device according to  claim 33 , the light shielding layer being disposed on both sides of the opening in cross-sectional view of the display device.  
   
   
       35 . The display device according to  claim 33 , the scattering layers being composed of a film with a roughened surface or an adhesive film with a light scattering function.  
   
   
       36 . The display device according to  claim 33 , the illumination device including: 
 a light source; and    a light guiding plate that guides light from the light source, the light guiding plate having a birefringence of about zero.    
   
   
       37 . The display device according to  claim 33 , the illumination device including an organic EL light that emits light from two surfaces to radiate a surface of the first liquid crystal panel and a surface of the second liquid crystal panel with light.  
   
   
       38 . A foldable cellular phone, comprising: 
 the display device according to  claim 33;  and    a body paired with the display device.    
   
   
       39 . An electronic device comprising the display device according to  claim 33.