Quality test device for inspecting vehicular display module having thin-film transistors

Patent metadata

Field	Value
Publication number	US-9538169-B2
Application number	US-201414531042-A
Country	US
Kind code	B2
Filing date	Nov 3, 2014
Priority date	Nov 3, 2014
Publication date	Jan 3, 2017
Grant date	Jan 3, 2017

Abstract

A quality test device tests a display device having a plurality of thin film transistors (TFTs). The quality test device includes a color analyzer for determining a color of an image displayed by the display device, and a quality inspection module. The quality inspection module controls a display state of the display device and determines whether the TFTs are adequately disposed within the display device based on a performance threshold. The quality inspection module determines that the display device is defective when a performance data of the display device is outside of the performance threshold, and determines that the display device is normal when the performance data is within the performance threshold.

First claim

What is claimed is:

1. A quality test device for testing a display device having a plurality of thin film transistors TFTs, the display device configured to be disposed in a vehicle, the quality test device comprising:
a color analyzer determining a color of an image displayed by the display device; and
a quality inspection module controlling the display device to a predetermined display state and determining whether the TFTs are adequately disposed within the display device based on a performance threshold stored in a computer readable medium, wherein
the color analyzer determines a color of the image displayed by the display device when the display device is controlled to the predetermined display state,
the quality inspection module calculates performance data based on the color detected by the color analyzer and a test parameter associated with the performance threshold,
the quality inspection module determines that the display device is defective when the performance data is outside of the performance threshold, and determines that the display device is normal when the performance data is within the performance threshold,
the quality inspection module controls the display device to a first state and a second state, and the predetermined display state includes the first state and the second state,
the color analyzer detects a first color of an image displayed by the display device when the display device is controlled to the first state and detects a second color of an image displayed by the display device when the display device is controlled to the second state,
the quality inspection module calculates the performance data based on the first color, the second color, and the test parameter,
the quality inspection module toggles the TFTs in an ON-OFF pattern to control the display device to the first state and toggles the TFTs in an OFF-ON pattern to control the display device to the second state, and wherein:
the ON-OFF pattern comprises a first set of the plurality of TFT in an ON position and a second set of the plurality of TFT in an OFF position,
the OFF-ON pattern comprises the first set of the plurality of TFT in an OFF position and the second set of the plurality of TFT in an ON position, and
both the first and second sets include multiple TFTs.

2. The quality test device of claim 1 wherein
when the display device is defective, the quality inspection module determines that one or more TFTs are not disposed correctly in the display device and
when the display device is normal, the quality inspection module determines that the TFTs are disposed correctly in the display device.

3. The quality test device of claim 1 wherein the performance threshold is based on a model display device that has all of the TFTs correctly disposed in the display device.

4. The quality test device of claim 1 wherein the color determined by the color analyzer is a chromaticity value in a chromaticity diagram.

5. The quality test device of claim 1 wherein
a plurality of the performance thresholds are stored in the computer readable medium,
the quality inspection module calculates a given performance data for a given performance threshold based on the color determined by the color analyzer and the test parameter associated with the given performance threshold, and
the quality inspection module determines that the display device is defective when one of the performance thresholds is not met.

6. A quality test device for testing a display device having a plurality of thin film transistors TFTs, the display device configured to be disposed in a vehicle, the quality test device comprising:
a color analyzer determining a color value of an image displayed by the display device; and
a quality inspection module controlling a display state of the display device to a first display state and a second display state and determining whether the TFTs are adequately disposed within the display device based on a performance threshold stored in a computer readable medium, wherein
the color analyzer determines a first color value of an image displayed by the display device when the display device is controlled to the first display state and a second color value of an image displayed by the display device when the display device is controlled to the second display state,
the quality inspection module calculates performance data based on the first color value, the second color value, and a test parameter associated with the performance threshold,
the quality inspection module determines that the display device is defective when the performance data is outside of the performance threshold, and determines that the display device is normal when the performance data is within the performance threshold,
the quality inspection module toggles the TFTs in an ON-OFF pattern to control the display device to the first display state and toggles the TFTs in an OFF-ON pattern to control the display device to the second display state, and wherein:
the ON-OFF pattern comprises a first set of the plurality of TFT in an ON position and a second set of the plurality of TFT in an OFF position,
the OFF-ON pattern comprises the first set of the plurality of TFT in an OFF position and the second set of the plurality of TFT in an ON position, and
both the first and second sets include multiple TFTs.

7. The quality test device of claim 6 wherein
the performance threshold includes a model parameter, an upper tolerance level, and a lower tolerance level,
the model parameter is based on the test parameter and a first model color value of an image displayed by a model display device when the model display device is operated in the first display state and a second model color value of an image displayed by the model display device when the model display device is operated in the second display state, and
the model display device has all of the TFTs connected correctly to a printed circuit board of the display device.

8. The quality test device of claim 6 wherein the test parameter includes calculating a difference between a color value of an image displayed by a given display device controlled to the first display state and a color value of an image displayed by a given display device controlled to the second display state.

9. The quality test device of claim 6 wherein the color analyzer is a colorimeter.

10. The quality test device of claim 6 , wherein the first color value and the second color value are chromaticity values in a chromaticity diagram.

11. A quality test method for determining a quality of a display device having a plurality of thin film transistors TFTs, the display device configured to be disposed in a vehicle, the method comprising:
controlling, by a quality test device, the display device to a first display state;
determining, by a color analyzer of the quality test device, a first color of an image displayed by the display device in the first display state;
controlling, by the quality test device, the display device to a second display state;
determining, by the color analyzer of the quality test device, a second color of an image displayed by the display device in the second display state;
determining, by the quality test device, a performance data of the display device based on the first color, the second color, and a test parameter;
comparing, by the quality test device, the performance data to a performance threshold associated with the test parameter, wherein the performance threshold is stored in a computer readable medium;
flagging, by the quality test device, the display device as defective when the performance data is outside of the performance threshold and as normal when the perform

Assignees

• Denso Int America Inc

Inventors

• Adams Christopher

Classifications

• G09G3/3648

  using an active matrix (G09G3/367 - G09G3/3696 take precedence) · CPC title

• G06T7/0002

  Inspection of images, e.g. flaw detection · CPC title

• G09G2360/145

  the light originating from the display screen · CPC title

• H04N17/00 Primary

  Diagnosis, testing or measuring for television systems or their details · CPC title

• G09G3/006 Primary

  Electronic inspection or testing of displays and display drivers, e.g. of LED or LCD displays (testing individual LED's G01R31/2635; testing lamps G01R31/44; testing of optical features of LCD displays G02F1/1309) · CPC title