Apparatus and method for reducing three-dimensional visual fatigue

Abstract

Disclosed are an apparatus and method for reducing 3D visual fatigue that a user feels when viewing a 3D image. An optimal 3D image may be regenerated and displayed without causing 3D visual fatigue and thus, it is possible to significantly reduce the 3D visual fatigue.

What is claimed is: 
     
         1 . An apparatus reducing three-dimensional (3D) visual fatigue, the apparatus comprising:
 a viewing distance estimator (detector) to estimate (detect) a user-to-screen distance from a screen to a user;   a 3D image analyzer to calculate a user-to-3D object distance based on the estimated user-to-screen distance and a parallax of a 3D image;   a 3D visual fatigue predictor to predict 3D visual fatigue of the user based on the estimated user-to-screen distance and the calculated user-to-3D object distance; and   a 3D image controller to control the 3D image based on the predicted 3D visual fatigue.   
     
     
         2 . The apparatus of  claim 1 , wherein the 3D image analyzer comprises:
 a pixel disparity calculator to read a first 3D image and a second 3D image from the 3D image, and to calculate a pixel disparity between the first 3D image and the second 3D image;   a physical disparity calculator to reflect a width and a horizontal resolution of the screen on the calculated pixel disparity, and to calculate a physical disparity; and   a user-to-3D object distance calculator to calculate the user-to-3D object distance based on the calculated pixel disparity and the calculated physical disparity.   
     
     
         3 . The apparatus of  claim 2 , wherein the user-to-3D object distance calculator calculates the user-to-3D object distance based on the calculated pixel disparity, the calculated physical disparity, and a distance between eyes of the user. 
     
     
         4 . The apparatus of  claim 1 , wherein the viewing distance estimator (detector) comprises:
 a viewing distance measuring unit to measure the user-to-screen distance; and   a viewing distance calculator to calculate the user-to-screen distance based on the measured distance.   
     
     
         5 . The apparatus of  claim 1 , wherein the viewing distance estimator (detector) estimates (detects) the user-to-screen distance using at least one of a monocular camera, a stereo camera, a multi-camera, a depth measurement camera, an ultrasonic distance measurement sensor, an infrared distance measurement sensor, and a laser distance measurement sensor. 
     
     
         6 . The apparatus of  claim 1 , wherein the 3D visual fatigue predictor comprises:
 a 3D visual fatigue model storage unit to store a 3D visual fatigue model, the 3D visual fatigue model comprising 3D visual fatigue information regarding at least one user-to-screen distance and at least one 3D viewing distance;   a 3D visual fatigue model-based predictor to predict the 3D visual fatigue based on the 3D visual fatigue model;   a fatigue-causing determiner to determine whether the 3D visual fatigue model causes the 3D visual fatigue; and   an optimal user-to-3D object distance calculator to calculate an optimal user-to-3D object distance using the 3D visual fatigue model when the 3D visual fatigue model is determined to cause the fatigue.   
     
     
         7 . The apparatus of  claim 6 , wherein the 3D visual fatigue model is stored in a storage. 
     
     
         8 . The apparatus of  claim 7 , wherein the stored 3D visual fatigue model is stored in a form of a lookup table or an approximated function. 
     
     
         9 . The apparatus of  claim 1 , wherein the 3D image controller comprises:
 an optimal physical disparity calculator to calculate an optimal physical disparity based on a calculated optimal user-to-3D object distance;   an optimal pixel disparity calculator to calculate an optimal pixel disparity based on the calculated optimal physical disparity; and   an optimal 3D image regenerator to regenerate a 3D image based on the calculated optimal physical disparity and the calculated optimal pixel disparity.   
     
     
         10 . The apparatus of  claim 1 , further comprising:
 a 3D image display unit to display a 3D image.   
     
     
         11 . A method of reducing 3D visual fatigue, the method comprising:
 estimating (detecting) a user-to-screen distance from a screen to a user;   calculating a user-to-3D object distance based on the estimated (detecting) user-to-screen distance and a parallax of a 3D image;   predicting 3D visual fatigue of the user based on the estimated (detected) user-to-screen distance and the calculated user-to-3D object distance; and   controlling the 3D image based on the predicted 3D visual fatigue.   
     
     
         12 . The method of  claim 11 , wherein the calculating comprises:
 reading a first 3D image and a second 3D image from the 3D image, and calculating a pixel disparity between the first 3D image and the second 3D image;   reflecting a width and a horizontal resolution of the screen on the calculated pixel disparity, and calculating a physical disparity; and   calculating the user-to-3D object distance based on the calculated pixel disparity and the calculated physical disparity.   
     
     
         13 . An apparatus to reduce three-dimensional (3D) visual fatigue, the apparatus comprising:
 a 3D visual fatigue predictor to predict 3D visual fatigue of a user based on a user-to-screen distance and a user-to-3D object distance; and   a 3D image controller to control a 3D image based on the predicted 3D visual fatigue,   wherein the 3D visual fatigue predictor comprises:   a 3D visual fatigue model-based predictor to predict 3D visual fatigue based on a 3D visual fatigue model using the user-to-3D object distance and the user-to-screen distance;   a fatigue-causing determiner to determine, using the 3D visual fatigue model, whether 3D visual fatigue occurs based on the predicted 3D visual fatigue, wherein the fatigue-causing determiner determines an occurrence of 3D visual fatigue when the predicted 3D visual fatigue is equal to or greater than a predetermined reference value; and   an optimal user-to-3D object distance calculator to calculate an optimal user-to-3D object distance using the user-to-screen distance and at least one user-to-3D object distance obtained from the 3D visual fatigue model, when the predicted 3D visual fatigue is equal to or greater than the predetermined reference value.