Method for generating signal to display three-dimensional(3d) image and image display apparatus using the same

Abstract

A method for generating a signal to display a three-dimensional (3D) image, and an image display apparatus using the same are disclosed. The method includes receiving a first synchronization signal, generating a second synchronization signal, and generating an output signal. Therefore, a user may satisfactorily view a 3D image regardless of whether the synchronization signal received from a display device reports errors or whether there is an obstruction between the display device and shutter glasses.

What is claimed is: 
     
         1 . A method for generating a signal to synchronize a shutter glasses unit with an external display, the method comprising:
 receiving, at the shutter glasses unit, an external synchronization signal from the external display;   generating, in the shutter glasses unit, an internal synchronization signal based on a periodic portion of the external synchronization signal; and   generating, in the shutter glasses unit, an output signal for controlling shutters of the shutter glasses unit based on the external synchronization signal and the internal synchronization signal.   
     
     
         2 . The method of  claim 1 , wherein the generating the output signal comprises:
 when the external synchronization signal indicates a high level, generating the output signal to correspond to the external synchronization signal; and   when the external synchronization signal indicates a low level, generating the output signal to correspond to the internal synchronization signal.   
     
     
         3 . The method of  claim 1 , wherein the generating the output signal comprises:
 generating the output signal to have a high level during time intervals when one at least one of the external synchronization signal and the internal synchronization signal is at a high level, and   generating the output signal to have a low level during time intervals when both the external synchronization signal and the internal synchronization signal are at a low level.   
     
     
         4 . The method of  claim 1 , further comprising:
 synchronizing, in the external display, the external synchronization signal and the external display alternatively displaying a first image frame and a second image frame.   
     
     
         5 . The method of  claim 1 , further comprising:
 synchronizing, in the external display, the external synchronization signal and the external display alternatively displaying a left eye image and a right eye image.   
     
     
         6 . The method of  claim 5 , further comprising:
 controlling the shutters of the shutter glasses unit using the output signal, wherein the controlling comprises opening a left-eye shutter of the shutter glasses unit when the external display unit is displaying a left eye image and opening a right-eye shutter of the shutter glasses unit when the external display unit is displaying a the right eye image.   
     
     
         7 . The method of  claim 6 , wherein the controlling the shutters further comprises:
 when the output signal indicates a high level, opening one of the left eye shutter and the right eye shutter; and   when the output signal indicates a low level, opening the other of the left eye shutter and the right eye shutter.   
     
     
         8 . The method of  claim 1 , wherein the generating the internal synchronization signal comprises repeating the periodic portion of the external synchronization signal, wherein a length of the periodic portion of the external signal is directly proportional to a cycle of the external synchronization signal. 
     
     
         9 . The method of  claim 1 , wherein the external synchronization signal is an infrared signal. 
     
     
         10 . The method of  claim 1 , wherein the generating the output signal comprises synchronizing the output signal with the external display of a left eye image and a right eye image. 
     
     
         11 . A shutter glass apparatus comprising:
 a receiver which receives an external synchronization signal from an external display which alternately displays a first image and a second image; and   a control unit which generates an internal synchronization signal based on a periodic portion of the external synchronization signal, and generates an output signal for controlling shutters of the shutter glass apparatus based on the external synchronization signal and the internal synchronization signal.   
     
     
         12 . The apparatus of  claim 11 , wherein the output signal corresponds to the external synchronization signal when the external synchronization signal indicates a high level; and the output signal corresponds to the internal synchronization signal when the external synchronization signal indicates a low level. 
     
     
         13 . The apparatus of  claim 11 , wherein the generated output signal is at a high level during time intervals when at least one of the external synchronization signal and the internal synchronization signal is at a high level, and
 the generated output signal is at a low level during time intervals when both the external synchronization signal and the internal synchronization signal are at a low level.   
     
     
         14 . The apparatus of  claim 11 , wherein the external synchronization signal is synchronized with the external display alternatively displaying of a first image frame and a second image frame. 
     
     
         15 . The apparatus of  claim 14 , wherein the first image frame is a left eye image and the second image frame is a right eye image. 
     
     
         16 . The apparatus of  claim 15 , wherein the shutter glass apparatus further comprises a glasses unit comprising shutters, a left eye glass, and a right eye glass, and the control unit controls the shutters using the output signal such that the left eye image is incident on the left eye glass of the glasses unit and the right eye image is incident on the right eye glass of the glasses unit. 
     
     
         17 . The apparatus of  claim 16 , wherein when the output signal indicates a high level, the control unit opens one of a left shutter and a right shutter; and when the output signal indicates a low level, the control unit opens the other of the left shutter and the right shutter. 
     
     
         18 . The apparatus of  claim 11 , wherein the control unit generates the internal synchronization signal by repeating the periodic portion of the external synchronization signal, wherein the periodic portion of the external synchronization signal is directly proportional to a cycle of the external synchronization signal. 
     
     
         19 . The apparatus of  claim 11 , wherein the external synchronization signal is an infrared signal. 
     
     
         20 . The apparatus of  claim 11 , wherein the output signal is synchronized with the external display of the first image and the second image.