Liquid crystal display apparatus and method for checking the joining accuracy thereof

• US 20040114064A1
• Filed: 12/10/2003
• Published: 06/17/2004
• Est. Priority Date: 12/26/2000
• Status: Active Grant

• Current Assignee: Ming-Cheng Tsai
• Original Assignee: Ming-Cheng Tsai
• Inventors: Tsai, Ming-Cheng
• Granted Patent: US 6,795,152 B2
• Time in Patent Office: Days
• US Class Current: 349/58
• CPC Class Codes: G02F 1/1309 Repairing; Testing
• CPC Class Codes: G02F 1/13452 Conductors connecting driver circuitry and terminals of panels
• CPC Class Codes: H05K 1/0268 for electrical inspection or testing
• CPC Class Codes: H05K 2203/166 Alignment or registration; Control of registration
• CPC Class Codes: H05K 3/361 Assembling flexible printed circuits with other printed circuits

Abstract

The present invention provides an LCD apparatus and a method for checking the joining accuracy thereof. The LCD apparatus comprises an LCD panel, a printed circuit board and a package unit coupled to the LCD panel. On the printed circuit board, there is a plurality of first pins, a first check pad and a second pad, wherein at least one first pin is electrically connected to the first check pad and at least another first pin is electrically connected to the second check pad. There is a plurality of second pins on the package unit, wherein the second pins join the first pins on the printed circuit board correspondingly to connect the first pins electrically. To check the joining accuracy of the LCD apparatus, electric resistance is obtained by measuring the resistance between the first and second check pad with an ohmmeter. When the measured resistance is below a reference value, the assembly quality of the LCD is not qualified.

Claims

1. A liquid crystal display (LCD) apparatus, comprising:

an LCD panel;

a printed circuit board with a plurality of first pins, a first check pad and a second pad thereon, at least one first pin electrically connected to the first check pad and at least another first pin electrically connected to the second check pad; and

a package unit coupled to the LCD panel with a plurality of second pins thereon corresponding to the first pins, wherein the second pins are electrically connected to the first pins.

2. The LCD apparatus as claimed in claim 1, wherein the package unit is a tape carrier package (TCP).

3. The LCD apparatus as claimed in claim 2, wherein the package unit comprises a driving circuit thereon for driving the LCD panel.

4. The LCD apparatus as claimed in claim 3, wherein the printed circuit board comprises a control circuit thereon for controlling the driving circuit.

5. The LCD apparatus as claimed in claim 4, wherein the second pins are electrically connected to the first pins by a anisotropic conductive film (ACF).

6. The LCD apparatus as claimed in claim 4, wherein the second pins are electrically connected to the first pins by solder.

7. A method for checking joining accuracy of a plurality of first pins on a printed circuit board and a plurality of second pins on a package unit, wherein the package unit is coupled to an LCD panel with the second pins thereon corresponding to the first pins for electrically connecting printed circuit board and the LCD panel, the method comprising the steps of:

providing a first check pad and a second check pad on the printed circuit board;

connecting at least one first pin to the first check pad;

connecting at least another first pin to the second check pad; and

measuring electric resistance between the first and the second pad to get the electric resistance which represents the electric resistance between the first and the second pins.

8. The method as claimed in claim 7, wherein the package unit is a tape carrier package (TCP).

9. The method as claimed in claim 8, wherein the package unit comprises a driving circuit thereon for driving the LCD panel.

10. The method as claimed in claim 9, wherein the printed circuit board comprises a control circuit thereon for controlling the driving circuit.

11. The method as claimed in claim 10, wherein the second pins are electrically connected to the first pins by a anisotropic conductive film (ACF).

12. The method as claimed in claim 10, wherein the second pins are electrically connected to the first pins by solder.