Liquid crystal display apparatus and testing method for liquid crystal display apparatus

1. A liquid crystal display apparatus, comprising:

a pixel array section including a plurality of unit pixels disposed in a matrix and each unit pixel including a pixel transistor, a capacitive element connected to an output electrode of said pixel transistor and a liquid crystal cell configured to display a gradation in accordance with a voltage retained in said capacitive element;

a first data line connected to an input electrode of each unit pixel of first pixel group in a unit of a pixel column from among the unit pixels of said pixel array section;

a second data line connected to an input electrode of each unit pixel of second pixel group in a unit of a pixel column from among the unit pixels of said pixel array section;

a writing unit configured to write a first measurement signal into the unit pixels of the first pixel group through the first data line and writing a second measurement signal into the unit pixels of the second pixel group through the second data lines line;

a voltage supply control unit configured to selectively supply a predetermined dc voltage to the first and second data lines;

a data line short-circuiting unit configured to short-circuit the first data line and the second data line after the voltage supplied by said voltage supply control unit;

a reading out unit configured to read out the first and second measurement signals from the unit pixels of the first and second pixel groups into the first and second data lines, respectively, after the first and second data lines are short-circuited to each other by said data line short-circuiting unit; and

a testing unit configured to compare the potential at the first data lines line and the potential at the second data line with each other after the reading out by said reading out unit and performing a test of said pixel array section based on a result of the comparison.

2. The liquid crystal display apparatus according to claim 1 , further comprising a switch unit provided at an input stage of said testing unit configured to selectively cut an electric connection between said testing unit and the first and second data lines.

3. The liquid crystal display apparatus according to claim 2 , wherein said data line short-circuiting unit is provided between said switch unit and said testing unit.

4. The liquid crystal display apparatus according to claim 1 , wherein said testing unit includes:

a comparison unit configured to compare the potential at the first data line and the potential at the second data line with each other after the reading out by said reading out unit; and

a decision unit configured to decide whether or not a result of the comparison by said comparison unit coincides with an expected value estimated from the first and second measurement signals.

5. A testing method for a liquid crystal display apparatus which includes a pixel array section including a plurality of unit pixels disposed in a matrix and each unit pixel including a pixel transistor, a capacitive element connected to an output electrode of said pixel transistor and a liquid crystal cell configured to display a gradation in accordance with a voltage retained in said capacitive element, a first data line connected to an input electrode of each unit pixel of first pixel group in a unit of a pixel column from among the unit pixels of said pixel array section, and a second data line connected to an input electrode of each unit pixel of second pixel group in a unit of a pixel column from among the unit pixels of said pixel array section comprising the steps of:

writing a first measurement signal into the unit pixels of the first pixel groups group through the first data line and writing a second measurement signal into the unit pixels of the second pixel group through the second data lines line;

selectively supplying a predetermined dc voltage to the first and second data lines after the first and second measurement signals are written at the writing step;

short-circuiting the first data line and the second data line after the voltage supplied at the voltage supply control step;

reading out the first and second measurement signals from the unit pixels of the first and second pixel groups into the first and second data lines, respectively, after the first and second data lines are short-circuited to each other at the short-circuiting step; and

testing by comparing the potential at the first data line and the potential at the second data line with each other after the reading out at the reading out step and performing a test of said pixel array section based on a result of the comparison.

6. The testing method for a liquid crystal display apparatus according to claim 5 , wherein the series of operations at the writing step, voltage supply step, short-circuiting step, reading out step and testing step is performed for each pixel row for each two adjacent pixel columns paired with each other in a unit of a division where all of the pixel columns of said pixel array section are divided into a plurality of divisions.