Field of the Disclosure
The present invention relates to a stereoscopic display device with a patterned retarder, and more particularly to a stereoscopic display device with a patterned retarder in which a brightness difference between a left eye image and a right eye image is compensated enabling to reduce a crosstalk, and a method for driving the same.
Discussion of the Related Art
The stereoscopic display device which displays a 3-dimensional (3D) image to have full of actuality has applications in many fields, such as medicine, education, movie, and television. The stereoscopic display device displays the left eye image and the right eye image separating the left eye image from the right eye image spatially or temporally for a watcher to perceive a 3D feeling owing to left and right parallactic images.
In methods for displaying the stereoscopic image, there are a glasses method in which a special glasses is used, and a non-glasses method in which no special glasses is used. In the glasses method, the left eye image and the right eye image are displayed on the display device changing polarization directions of the left eye image and the right eye image, or separating the left eye image form the right eye image by a time sharing method, for the watcher to perceive a 3D effect by using a polarizing glasses or a liquid crystal shutter glasses. In the non-glasses method, the stereoscopic image is displayed by using an optical plate, such as a lenticular sheet, or parallax barrier, mounted to a front or a rear of the display device.
The glasses type stereoscopic display device using the polarizing glasses displays the left eye image and the right eye image on a pixel matrix in horizontal pixel lines alternately, and converts the left eye image and the right eye image into a left-circular polarization image and a right-circular polarization image by using a patterned retarder attached to a front, respectively. The patterned retarder has a structure in which first and second polarization films which convert a linearly polarized light into a left-circular polarized light and a right-circular polarized light are arranged alternately in an up/down direction matched to left eye image lines (Odd lines) and right eye image lines (Even lines) arranged on the display device, alternately. The polarizing glasses makes spatial separation of the left eye image and the right eye image having polarization directions different from each other by using a left eye lens and a right eye lens which transmit the left-circular polarized light and the right-circular polarized light respectively for the user to perceive the 3D effect owing to left and right parallactic images.
In the display device which displays the left eye image and the right eye image in the horizontal pixel lines alternately, there has been a problem that a difference of overlap between a data line and pixels (i.e., a difference of parasitic capacitance) causes a difference of brightness between the odd line and the even line. The difference of overlap between the data line and pixels is caused, in a liquid crystal display device having data lines arranged in zigzag, by a difference of an overlap area between the data line of zigzag type and an upper side pixel, and an overlap area between the zigzag shaped data line and a lower side pixel.
Referring to FIG. 1, in the stereoscopic display device which displays the right eye image R and the left eye image L on the even lines and the odd lines respectively, in a case gray scales R255, R127, R63, R0 of the even image are varied while the gray scale R191 of the left eye image is fixed, the brightness of the left eye image lines varies in a range of +3.4˜−6.5 nit due to interference of the right eye image lines, causing a brightness difference on the same gray scale.
The brightness difference between the odd line and the even line causes a brightness difference between the left eye image and the right eye image, increasing an extent of crosstalk between the left eye image and the right eye image.