WO2012023792A2

WO2012023792A2 - Probe unit for testing lcd panel

Info

Publication number: WO2012023792A2
Application number: PCT/KR2011/006027
Authority: WO
Inventors: Yi Bin Ihm; Nam Jung Her; Jun Soo Cho; Jong Hyun Park
Original assignee: Pro-2000 Co. Ltd.
Priority date: 2010-08-18
Filing date: 2011-08-17
Publication date: 2012-02-23
Also published as: CN103069281A; TW201219792A; KR101043818B1; WO2012023792A3

Abstract

A probe unit is provided. The probe unit for testing a liquid crystal panel includes a body block configured to have a bottom surface to which a tab IC film for use in the liquid crystal panel is attached while one end of the tab IC film is folded, and allow metal lines formed on the tab IC film to be in one-to-one contact with electrode lines formed on the liquid crystal panel; and a flexible printed circuit board configured to be electrically connected to the other end of the tab IC film and provide a test signal to the liquid crystal panel through the tab IC film.

Description

PROBE UNIT FOR TESTING LCD PANEL

The following description relates to a probe unit, and more particularly, to a probe unit with a structure for testing a liquid crystal panel such as a liquid crystal display and a plasma display panel.

FIG. 1 illustrates a plan view of an example of a liquid crystal display device having a general film-type package.

Referring to FIG. 1, the liquid crystal display device includes a printed circuit board 100, a tab IC film 120, and a liquid crystal panel 110. The printed circuit board 100 has various installed elements such as a control unit (not illustrated) and a driving voltage generating unit (not illustrated). The control unit on the printed circuit board 100 outputs a control signal, and the driving voltage generating unit outputs voltages necessary for operation of the display device, for example, a power voltage, a gate-on voltage, a gate-off voltage, and the like.

The tab IC film 120 includes an upper bonding pad 121 on which a driver IC 125 is mounted, and the upper bonding pad 121 is electrically connected to a bonding pad (not illustrated) of the printed circuit board 100. In addition, a lower bonding pad 123 of the tab IC film 120 is electrically connected to the liquid crystal panel 110. The driver IC 125 formed on the tab IC film 120 transmits a signal to drive and test the liquid crystal panel 110, and the tab IC film 120 is a film sheet on which the driver IC 125 is mounted and metal lines (wiring) are formed to transmit the signal.

FIG. 2 illustrates a conceptual diagram depicting a structure of an existing probe unit to test the liquid crystal panel shown in FIG. 1.

As liquid crystal panels have advanced in function, an interval (pitch) between electrode lines (metal wiring) on the liquid crystal panel becomes much narrower. The existing probe unit 400 uses the structure as shown in FIG. 2 when testing such liquid crystal panel.

Referring to FIG. 2, a socket S of a module M of the probe unit 400 is connected to the TCP block TCP via a flexible printed circuit board FPCB, and a body block B having a probe NDL is interposed between the TCP block TCP and the liquid crystal panel 110. The module M includes a control chip TCON.

On a lower surface of the TCP block TCP, a tab IC film that is the same as the tab IC film 120 to be mounted on the liquid crystal panel 110 is mounted.

In addition, a front edge of the tab IC film 120 having a guide film GF comes in direct contact with the probe NDL.

The body block B has the probe NDL mounted thereon, which has one end in direct contact with the electrode lines LD of the panel 110 and the other end in direct contact with the metal lines of the tab IC film 120 through a hole (for fixing a position) of the guide film GF of the TCP block. The panel 110 may be tested through the driver IC 125 of the tab IC film 120.

However, as noted in FIG. 2, when the end of the probe NDL mounted on the body block B comes in direct contact with the electrode lines LD of the panel 110, the sharp ends of the probe NDL may scratch the electrode lines LD. The scratches may damage the electrode lines LD, and fine particles generated from the electrode lines LD due to the scratches may electrically connect adjacent electrode lines LD, which may cause a defect.

Since the pitch between the electrode lines LD of the panel becomes finer, a probe unit for testing the panel becomes more complicated to manufacture.

In addition, the probe NDL having the same pitch as the pitch between the electrode lines LD of the panel 110 is to be mounted on the body block B, and the body block B including the probe NDL is required to be newly designed each time the liquid crystal panel 110 is modified, which problematically increases the cost of test.

Furthermore, a new probe unit structure has been suggested, which tests a liquid crystal panel using metal lines formed on a film sheet, instead of a needle-type probe NDL as shown in FIG. 2. However, a film sheet that has the same pitch as the electrode lines of the liquid crystal panel should be used, and thus an additional film sheet needs to be manufactured, which has problems in cost and practicality.

The following description relates to a probe unit having a structure which is used as a probe-pin for testing a liquid crystal panel by mounting a tab IC film on a bottom surface of a body block wherein the tab IC film is actually used for the liquid crystal panel as a test target, and which allows accurate alignment with the liquid crystal panel and prevents a burning phenomenon.

In one general aspect, a probe unit for testing a liquid crystal panel including: a body block configured to have a bottom surface to which a tab IC film for use in the liquid crystal panel is attached while one end of the tab IC film is folded, and allow metal lines formed on the tab IC film to be in one-to-one contact with electrode lines formed on the liquid crystal panel; and a flexible printed circuit board configured to be electrically connected to the other end of the tab IC film and provide a test signal to the liquid crystal panel through the tab IC film.

The body block may have the lower surface tilted down toward its leading edge and has an insertion groove formed on the leading edge and the buffer block may be inserted into the insertion groove and has an end protruding to the outside of the insertion groove.

The end of the buffer block that protrudes to the outside of the insertion groove may be made to be pointed and be parallel to the bottom surface of the body block, and the buffer block may be made of a workable non-metallic material.

The tab IC film may be mounted to protrude over an edge of the buffer block so as to facilitate the alignment with the electrode lines of the liquid crystal panel, and a first member may be inserted between the tab IC film and the folded end of the tab IC film. The first member may be an adhesive tape that provides elasticity and adhesion while maintaining a predefined space between the tab IC film and the folded end of the tab IC film.

A second member may be inserted between the buffer block, the body block and the tab IC film to evenly press the metal lines of the tab IC film downward, and the second member may not protrude outside of the buffer block and is attached onto the buffer block and the bottom surface of the body block. The second member may be an insulation-coated metal plate.

An elastic groove may be formed on the bottom surface of the body block toward an inner end of the insertion groove to produce elasticity on the bottom surface of the body block when the tab IC film is in contact with the panel.

The tab IC film may be fixed onto the bottom surface of the body block via an adhesive, the flexible printed circuit board may be in contact with a rear surface of the tab IC film, and an auxiliary fixation unit may be mounted on a lower portion of the body block to press and fix the flexible printed circuit board and the tab IC film to each other. The flexible printed circuit board may have a current block device on the metal lines so as to prevent a burning phenomenon from occurring during test of the liquid crystal panel. The current block device may be a diode and be formed on the electrode lines of the flexible printed circuit board along a direction of the panel.

The metal lines which are formed on the tab IC film mounted on the bottom surface of the body block may have an interval therebetween which is adjusted to match an interval between the electrode liens of the liquid crystal panel.

Among the metal lines formed on the tab IC film mounted on the bottom surface of the body block, metal lines that are in direct contact with the electrode lines of the liquid crystal panel not through a driver IC provided on the tab IC film may be formed by etching on a metal plate.

The metal lines in direct contact with the electrode lines of the liquid crystal panel, not through the driver IC, may be metal lines for providing electrical signals to a gate IC of the liquid crystal panel.

Portions of the metal lines formed on tab IC film which are in contact with the liquid crystal panel may be surface-processed with a high conductive material stable to thermal oxidation so as to prevent a burning phenomenon due to a high voltage generated when contacting with the electrode lines of the liquid crystal panel.

Probe lead lines formed on the tab IC film mounted on the bottom surface of the body block may be surface-processed with a high conductive material stable to thermal oxidation so as to prevent a burning phenomenon due to a high voltage generated when contacting with the electrode lines of the liquid crystal panel. The high conductive material for surface-processing may be gold (Au) or nickel (Ni).

Among the metal lines formed on the tab IC film mounted on the bottom surface of the body block, metal lines that are in direct contact with the electrode lines of the liquid crystal panel not through a driver IC provided on the tab IC film may be formed to be blade-tip type metal lines.

As apparent above, a probe unit according to an exemplary embodiment of the present invention uses a tab IC film intact that is mounted on a liquid crystal panel to be tested, and thus can easily and accurately test the liquid crystal panel.

In addition, since metal lines formed on the tab IC film are in direct contact (surface contact) with electrode lines of the liquid crystal panel, there is no risk to damage to the electrode lines of the liquid crystal panel and thus a scrub mark and particles are prevented from occurring. In addition, since the tab IC filmthat is mounted on the liquid crystal panel is used itself, the present invention is applicable to any type of panel patterns and pitches.

FIG. 1 is a plan view showing an example of a liquid crystal display device having a general film-type package.

FIG. 2 is a conceptual diagram depicting a structure of an existing probe unit to test a liquid crystal panel shown in FIG. 1.

FIG. 3 is a side view of a probe unit according to an exemplary embodiment of the present invention.

FIG. 4 is an enlarged view showing a front portion of the probe unit illustrated in FIG. 3.

FIG. 5 is an enlarged view showing the electrode lines of the panel to be tested.

FIG. 6 is a conceptual diagram illustrating the electrode lines of the panel that are connected to metal lines disposed on a bottom surface of an existing body block.

FIG. 7 is a diagram for explaining an electrical path that is formed when different levels of voltages are applied to metal lines connected by a fine particle as shown in FIG. 6.

FIG. 8 is a diagram depicting an example of a tab IC film TIC in contact with a flexible printed circuit board (FPCB).

FIG. 9 is a conceptual diagram depicting a probe unit in contact with a panel.

FIG. 10 is a conceptual diagram depicting an example of a function of the current block device.

FIG. 11 is a diagram illustrating an example of a tab IC film.

FIG. 12 is a diagram illustrating an example of a tab IC film having a portion replaced with a metal plate.

FIG. 13 is a diagram illustrating an example of a tab IC film including metal lines of which end portions are surface-processed.

FIG. 14 is a picture of an example of a tab IC film using the plate as shown in FIG. 12.

The following description is provided to assist the reader in gaining a comprehensive understanding of the methods, apparatuses, and/or systems described herein. Accordingly, various changes, modifications, and equivalents of the methods, apparatuses, and/or systems described herein will be suggested to those of ordinary skill in the art. Also, descriptions of well-known functions and constructions may be omitted for increased clarity and conciseness.

FIG. 3 illustrates a side view of a probe unit according to an exemplary embodiment of the present invention.

FIG. 4 illustrates an enlarged view of a front portion of the probe unit illustrated in FIG. 3.

Referring to FIGS. 3 and 4, the probe unit for use to test a panel may include a body block (BB) and a flexible printed circuit board (FPCB).

The BB shown in FIG. 3 may be mounted on a bottom surface of a manipulator (not shown). A tab IC film TIC for use in a liquid crystal panel is attached to a bottom surface of the BB, with one end being bent. Metal lines (ML) formed on the tab IC film TIC may be in one-to-one contact with electrode lines (LD) formed on the liquid crystal panel.

The FPCB may be electrically connected to another end of the tab IC film TIC and transmit a test signal to the liquid crystal panel 110 through the tab IC film TIC.

In this case, the tab IC film TIC is the same film as used when the crystal panel 110 is connected to a printed circuit board 100 shown in FIG. 1 after test.

The TIC is provided directly by a manufacturer of the liquid crystal panel 110 and then used for the probe unit.

In other words, according to the exemplary embodiment the probe unit to be mounted on a probe base (not shown) may have a structure which removes a conventional body block having a pin-shaped probe installed thereon and being mounted on the manipulator and instead has a tab IC film TIC mounted on a bottom surface of the body block BB to function as a probe wherein the tab IC film TIC is the same as a tab IC film used for the liquid crystal panel to be tested. Accordingly, the tab IC film TIC is allowed to be in one-to-one direct contact with the electrode lines (LD) of the liquid crystal panel 110.

In this case, the tab IC film TIC is attached to a bottom surface BBM of the body block BB via adhesion, and is integrated with the body block BB without using an additional structure.

As shown in FIG. 3, the body block BB may have screw thread holes (not shown) on a top surface for engagement with the manipulator. In addition, the body block BB may have the bottom surface BBM tilted down toward its leading edge. This is to ensure the contact between the metal lines MN of the tab IC film TIC in contact with the bottom surface BBM of the body block BB and the electrode lines LD of the liquid crystal panel 110.

The bottom surface of the body block BB is flat as shown in FIG. 3, and the tab IC film TIC is directly adhered to the flat bottom surface BBM to be integrated with the body block BB. The other surface of the tab IC film that is not adhered to the body block BB has a driver IC 830 and the metal lines ML formed thereon.

Moreover, the leading edge of the body block BB may have an insertion groove 321 into which a buffer block 320 is inserted. The buffer block 320 is inserted into the insertion groove 321 with pressure and has an end protruding to the outside of the insertion groove 321. The buffer block 320 which is inserted into the insertion groove 321 with pressure may be screw-coupled with the body block BB via a coupling member 325 (for example, an assembly screw) that is inserted into a groove 323 formed on the body block BB as shown in FIG. 3. In this case, the buffer block 320 has to have a groove through which the coupling member 325 passes.

The end of the buffer block 320 protruding to the outside of the insertion groove 321 is made to be pointed and be parallel to the bottom surface of the body block BB. The buffer block 320 is made of a workable non-metallic material, which is hard enough to be molded but elastic, and examples of such material may include rubber, urethane, silicone, and moldable resin. The buffer block 320 supports the tab IC film TIC from the side opposite to a contact surface between the tab IC film TIC and the liquid crystal panel 110, thereby maintaining flatness of the tab IC film TIC and providing elastic buffer against the impact occurring when the metal lines ML of the tab IC film TIC come in contact with the electrode lines LD of the liquid crystal panel 110. As a result, the liquid crystal panel 110 is prevented from being crashed or damaged.

The buffer block 320 may be in a shape of a rectangular block, have a length the same as or longer than a width (a direction along which the metal lines are arranged) of the tab IC film TIC, and have the pointed end. By doing so, the bottom surface BBM of the body block BB can be parallel to the pointed end of the buffer block 320, so that it becomes easy for the tab IC film TIC to be in contact in the bottom surface BBM of the body block BB. The insertion groove 321 may be formed at a variety of angles.

The tab IC film TIC may be disposed in such a manner that protrudes over the end of the buffer block 320 so as to facilitate the alignment with the corresponding electrode lines LD on the liquid crystal panel 110. The tab IC film TIC may protrude about 0.01 mm - 0.5 mm from the end of the buffer block 320.

Between the tab IC film TIC and a folded portion TICUP of the tab IC film, a first member 333 may be inserted. The first member 333 may be a double-sided tape that provides elasticity and adhesion effects while maintaining a predefined space between the tab IC film TIC and the folded portion TICUP.

When the tab IC film TIC is adhered to the bottom surface BBM of the body block BB, a predefined length of the end of the tab IC film TIC is folded upward, as shown in FIGS. 3 and 4. A lower surface of the tab IC film TIC has the metal lines (metal wirings ML) formed thereon for transmission of signals from the driver IC 830. As the end of the tab IC film TIC is folded upward, the metal lines ML on the lower surface are exposed upward as shown in FIG. 4. In addition, the folded end of the tab IC film TIC is in contact with the bottom surface BBM of the body block BB (see FIG. 4). The first member 333 is adhered between the tab IC film TIC and the folded portion TICUP of the tab IC film TIC to provide elasticity therebetween, and, as shown in FIG. 4, prevents the metal lines ML from being completely bent on the folded end of the tab IC film TIC, thereby preventing the crack of the metal lines ML.

The top surface of the body block BB is curved with a slope, as shown in FIG. 3, to allow the end of the body block BB, that is, the end of the buffer block 320 to be seen more clearly when a user views from the top. The end of the tab IC film TIC protrudes more than the end of the buffer block 320, and is folded upward to allow the metal lines ML to be exposed upward, and therefore the alignment for one-to-one surface contact between the metal lines ML on the tab IC film TIC and the electrode lines LD on the liquid crystal panel 110 can be easily achieved.

A second member 330 may be inserted between the buffer block 320, the body block BB and the tab IC film TIC so as to evenly press the metal lines ML downwards. Referring to FIG. 4, the second member 330 may protrude the same length as the buffer block 320 from the body block BB, and may be adhered to the buffer block 320 and the bottom surface BBM of the body block BB. The second member 330 may be an insulation-coated metal plate, for example, steel use stainless (SUS). As shown in FIG. 4, the second member 330 is insulation-coated since it is in contact with the metal lines ML.

The second member 330 is provided to block the contact between the buffer block 320 and the metal lines ML of the tab IC film TIC, thereby prevent burning from occurring in the buffer block 320.

The tab IC film TIC is fixed to the bottom surface BBM of the body block BB via an adhesive, and the FPCB is in contact with a rear surface of the tab IC film (TIC). Additionally, an auxiliary fixation unit 335 may be further mounted on a lower portion of the body block BB to fix the FPCB and the tab IC film TIC. Referring to FIG. 3, the auxiliary fixation unit 335 at the lower portion of the body block BB may press the tab IC film TIC mounted on the bottom surface BBM of the body block BB and the FPCB connected to a tail edge of the tab IC film TIC toward the body block BB. In this case, an elastic structure 337 formed on the auxiliary fixation unit 335 may press and fix the tab IC film TIC and the FPCB to each other. A fastening member 339 may be inserted into a fastening groove 341 so that the auxiliary fixation unit 335 can be mounted onto the body block BB. The fastening member 339 may be a screw or a bolt.

When the auxiliary fixation unit 335 is separated from the body block BB by releasing the fastening member 339, the FPCB can be removed from the tab IC film TIC. Thus, if the FPCB is damaged, the FPCB can be individually replaced.

The bottom surface BBM of the body block BB may have an elastic groove 327 in a direction to an inner end of the insertion groove 321. As shown in FIG. 3, the elastic groove 327 is a groove formed on the bottom surface BBM of the body block BB and functions as a leaf spring that produces elasticity when the tab IC film TIC comes in contact with the liquid crystal panel 110, and thereby enabling a pressing force from the bottom surface BBM of the body block BB to be more effectively delivered to the tab IC film TIC, and easing a force applied to the liquid crystal panel 110 with the elasticity. That is, when the electrode lines LD of the panel 110 in contact with the end of the tab IC film TIC is pressed, the bottom surface BBM of the body block BB may be moved slightly upward owing to an empty space of the elastic groove 327, and thereby the pressing force on the panel 110 can be reduced.

As described above, the probe unit with the tab IC for use in the liquid crystal panel 110 to be tested may enable testing the liquid crystal panel accurately and easily.

A tab IC film is used for the liquid crystal panel 110 to be tested is used itself as the tab IC film TIC to be adhered to the bottom surface of the body block BB, as described above. In practice, however, metal lines formed on the tab IC film to be mounted on the liquid crystal panel 110 have an interval therebetween that is slightly narrower than an interval between electrode lines LD on the liquid crystal panel 110.

Thus, in a case of use of a tab IC film mounted on the liquid crystal panel 110 to be tested as the tab IC film TIC to be mounted on the bottom surface BBM of the body block BB, the interval between the metal lines formed on the tab IC film TIC is required to be adjusted. In the exemplary embodiment, the interval between the metal lines on the tab IC film TIC to be mounted on the bottom surface BBM of the body block BB may be gradually increased to match the interval between electrode lines LD on the panel 110 to be tested.

To widen an interval between metal lines on the tab IC film TIC, while fixing one side of the tab IC film TIC, the other side is stretched out to make the interval between the metal lines wider. A method for widening the interval between the metal lines of the tab IC film TIC may be understood by those skilled in the art, and thus detailed description will be omitted.

The burning phenomenon occurs during a liquid crystal panel test, and in this phenomenon, a heat is produced by an overcurrent between electrode lines having different electric potentials and the produced heat melts and damages a contact portion between the probe unit and the electrode lines LD of the panel 110 when an abnormal electrical connection is established between the electrode lines of the liquid crystal panel 110 to which different voltages are applied upon contacting between the probe unit and the panel 110 for supply of an electrical signal and power to the liquid crystal panel 110.

The occurrence of burning phenomenon affects the probe unit to test and the panel 110 as a test target, and thus resulting in a substantial loss of productivity.

FIG. 5 illustrates an enlarged view of the electrode lines of the panel to be tested, and FIG. 6 illustrates a conceptual diagram of the electrode lines of the panel that are connected to metal lines disposed on a bottom surface of an existing body block. In FIGS. 5 and 6, some metal lines LD of the panel 110 are connected to one another via a fine particle R.

FIG. 7 illustrates a diagram for explaining an electrical path that is formed when different levels of voltages are applied to metal lines connected by a fine particle as shown in FIG. 6. A current of several hundreds of mA flows through the electrical path, and generally a heat generated by a current of about more than 250 mA flowing through the electrical path may deform the tab IC film TIC that supports the metal lines PRLD1 and RRLD2. Furthermore, a greater current may cause the burning phenomenon in which a contact portion between the metal lines PRLD1 and PRLD2 and electrode lines LD of the panel 110 is instantaneously melted.

Therefore, it is required to prevent the overcurrent flow.

In one example, the FPCB is in direct contact with a rear surface of the tab IC film TIC, and includes electrode lines FLD that are electrically connected to the metal lines PRLD of the tab IC film TIC.

FIG. 8 illustrates a diagram depicting an example of a tab IC film TIC in contact with an FPCB.

In the example, a current block device 1000 is disposed on electrode lines FLD to prevent the burning phenomenon during panel test. The current block device 1000 may block an overcurrent flow to prevent the burning phenomenon from occurring.

FIG. 9 illustrates a conceptual diagram depicting a probe unit in contact with a panel.

Referring to FIG. 9, the FPCB having the current block device 1000 is connected to a tab IC film TIC adhered onto a bottom surface BBM of the body block BB.

In particular, the current block device 1000 may be formed of a resistor, a varistor, a poly-switch, and the like, as well as a diode, and be arranged on the electrode lines FLD of the FPCB along a direction of the panel 110.

FIG. 10 illustrates a conceptual diagram depicting an example of a function of the current block device.

In FIG. 10, on a path through which a voltage is applied to each of the metal lines LD of the panel 110, the current block device 1000, that is, a diode is formed. More specifically, as described above, besides the diode, a current block device such as a resistor, a varistor, a poly-switch, and the like is formed in series on the electrode lines FLD of the FPCB.

Even if an electrical path is made between adjacent lead lines due to a fine particle R, a current is blocked by the diode from flowing from a higher electric potential of 30 V into a lower electric potential of 3V. As a result, a lower electric potential side is blocked, and the voltage of 30 V is applied to the lead lines connected by the fine particle R. In this case, an overcurrent does not flow into the panel 110 in a normal state, and thus an increase in overall current measured in the panel 110 is so negligible that the burning phenomenon due to the overcurrent does not occur.

Compared to the conventional method which does not employ any particular means to prevent the burning phenomenon which frequently occurs during display panel test, the present invention may considerably increase the productivity of the panel 110.

Although in the above example, the current block device 1000 is disposed on the FPCB, it may be disposed on a driving module M. In this case, since the driving module M is not designed to be used for the panel 110 to be tested, an individual driving module is required for the panel 110. The current block device 1000 may be disposed at a variety of positions for the convenience of design. For example, to prevent the burning phenomenon, the current block device 1000 may be a surface-mounted PCB or be gender-shaped. In this case, the PCB and the gender are required to have an individual connector for connection with the FPCB.

In testing the liquid crystal panel 110, a burning phenomenon may occur on a contact portion between the electrode lines LD of the panel 110 and the metal lines PRLD of the tab IC film TIC, that is, ends of the metal lines PRLD of the tab IC film. Due to the burning phenomenon, contact resistance is increased on the ends of the metal lines PRLD, which makes it difficult to deliver a stable voltage to the panel 110, and accordingly an inaccurate test may be caused.

The burning phenomenon on the contact portion frequently occurs on metal lines to which higher voltages are applied from among the metal lines PRLD of the tab IC film TIC. This is because when the metal lines PRLD of the tab IC film TIC are in contact with the metal lines LD of the panel 110, a high voltage current instantaneously flows into the metal lines RRL, and it changes metal properties of the contact portion of the metal lines PRLD.

Generally, the metal lines PRLD of the tab IC film TIC may be made by surface-processing copper (Cu) patterns with tin (Sn). The surface processing with tin (Sn) is to prevent corrosion of the copper (Cu) and to utilize soldering characteristics of tin which can be soldered at a relatively low temperature when attaching the driver IC 830 onto the tab IC film. However, the burning phenomenon may occur on the tinned metal lines due to a heat generated when a higher current flows into the metal lines.

FIG. 11 illustrates a diagram of an example of a tab IC film.

Metal lines PRLD are classified into two groups: one group of metal lines RPLDa are in direct contact with electrode lines LD of a panel 110 not through a driver IC 830, and the other group of metal lines PRLDb are connected to the electrode lines LD of the panel 110 via the driver IC 830.

The metal lines PRLDa generally provide an electrical signal and power to a gate IC (not shown) of the liquid crystal panel 110. The gate IC is formed on each side of the liquid crystal panel 110. The metal lines PRLDa of the tab IC film TIC provide the electrical signal and power to the gate IC not through the driver IC 830.

Since a voltage used for the gate IC is higher than other voltages to be provided to the panel 110, an abnormal spark may be generated at a contact point between the electrode lines LD of the panel 110 and the metal lines PRLDa of the tab IC film TIC, and as a result, a burning phenomenon occurs on a tinned surface of the metal lines PRLDa.

Hence, it is important to prevent the burning phenomenon. For example, the metal lines PRLDa that are formed on the tab IC film TIC mounted on a bottom surface of the body block BB and are in direct contact with the electrode lines LD of the panel 110 not through the driver IC 830 of the tab IC film TIC may be metal lines PTN formed by etching on a metal plate 1200 having the same length as the tab IC film (referring to FIG. 12).

The metal lines PRLDa in direct contact with the electrode lines LD of the panel 110 are metal lines to provide electrical signals to the gate ICs of the panel 110.

In other words, the metal lines for providing electrical signals to the gate ICs of the panel 110 are power lines through which high voltage signals pass, and a burning phenomenon due to a spark may occur between the metal lines and the electrode liens LD of the panel 110. To prevent the burning phenomenon, metal lines PTN formed by etching on the thin metal plate 1200 are used to replace the conventional metal lines of the tab IC film TIC.

As shown in FIG. 12, the metal plate 1200 having a pattern of the etched metal lines PTN may be attached to the tab IC film TIC, instead of the metal lines PRLDa shown in FIG. 11. The metal plate 1200 may be a thin etchable plate formed of beryllium nickel or beryllium copper, and may be bonded to the tab IC film TIC by adhesion.

Probe lead lines PTN as metal lines PTN are formed by etching on the plate 1200 to provide electrical signals to the gate ICs of the panel 110.

Unlike the example shown in FIG. 7B, metal lines PRLD formed on the tab IC film TIC as shown in FIG. 13 may have ends 1210 that are in contact with the panel 110 and are surface-processed with a high-conductive material stable to thermal oxidation so as to prevent the burning phenomenon due to a high voltage generated when contacting the electrode lines LD of the panel 110.

In other words, the surface-processing is to form a stable metal layer by removing tin (Sn) from the ends 1210 of the metal lines PRLD, and the high conductive material stable to thermal oxidation as the stable metal layer may be a material such as gold (Au) or nickel (Ni) that has a superior electric conductivity and is not oxidized. However, the high conductive material for the surface processing is not limited thereto.

As such, the ends of the metal lines PRLD from which tin has removed are covered with a metal layer such as gold or nickel, so that the burning phenomenon can be prevented from occurring on a contact portion of the metal lines PRLD.

Instead the method of forming the metal layer such as gold or nickel on the ends 1210 of the metal lines PRLD as shown in FIG. 13, the whole metal lines PRLD on the tab IC film TIC may be surface-processed with stable metal such as gold or nickel.

FIG. 14 is a picture of an example of a tab IC film using the plate as shown in FIG. 12. The picture is taken from a lower portion of the body block BB of the probe unit according to the exemplary embodiment. Referring to FIG. 14, in the right-handed side of the tab IC film TIC, the plate 1200 is bonded onto the film TIC and has etched metal lines PTN. At a rear side of the tab IC film TIC, an FPCB is connected.

Among metal lines formed on the tab IC film TIC mounted on a bottom surface of the body block BB, metal lines PRLDa in direct contact with lead lines LD of the panel 110 without the help of the driver IC 830 may be formed to be blade-tip type metal lines.

The high voltage signal lines formed as the blade-tip type may reduce the occurrence of the burning phenomenon due to particles during manufacturing, and may prevent the burning phenomenon utilizing the blade's material properties.

A number of examples have been described above. Nevertheless, it should be understood that various modifications may be made. For example, suitable results may be achieved if the described techniques are performed in a different order and/or if components in a described system, architecture, device, or circuit are combined in a different manner and/or replaced or supplemented by other components or their equivalents. Accordingly, other implementations are within the scope of the following claims.

Claims

A probe unit for testing a liquid crystal panel, comprising:

a body block configured to have a bottom surface to which a tab IC film for use in the liquid crystal panel is attached while one end of the tab IC film is folded, and allow metal lines formed on the tab IC film to be in one-to-one contact with electrode lines formed on the liquid crystal panel; and

a flexible printed circuit board configured to be electrically connected to the other end of the tab IC film and provide a test signal to the liquid crystal panel through the tab IC film.
The probe unit of claim 1, wherein the body block has the lower surface tilted down toward its leading edge and has an insertion groove formed on the leading edge and the buffer block is inserted into the insertion groove and has an end protruding to the outside of the insertion groove.
The probe unit of claim 2, wherein the end of the buffer block that protrudes to the outside of the insertion groove is made to be pointed and be parallel to the bottom surface of the body block, and the buffer block is made of a workable non-metallic material.
The probe unit of claim 3, wherein the tab IC film is mounted to protrude over an edge of the buffer block so as to facilitate the alignment with the electrode lines of the liquid crystal panel, and a first member is inserted between the tab IC film and the folded end of the tab IC film.
The probe unit of claim 4, wherein the first member is an adhesive tape that provides elasticity and adhesion while maintaining a predefined space between the tab IC film and the folded end of the tab IC film.
The probe unit of claim 3, wherein a second member is inserted between the buffer block, the body block and the tab IC film to evenly press the metal lines of the tab IC film downward, and the second member does not protrude outside of the buffer block and is attached onto the buffer block and the bottom surface of the body block.
The probe unit of claim 6, wherein the second member is an insulation-coated metal plate.
The probe unit of claim 3, wherein an elastic groove is formed on the bottom surface of the body block toward an inner end of the insertion groove to produce elasticity on the bottom surface of the body block when the tab IC film is in contact with the panel.
The probe unit of claim 3, wherein the tab IC film is fixed onto the bottom surface of the body block via an adhesive, the flexible printed circuit board is in contact with a rear surface of the tab IC film, and an auxiliary fixation unit is mounted on a lower portion of the body block to press and fix the flexible printed circuit board and the tab IC film to each other.
The probe unit of claim 9, wherein the flexible printed circuit board has a current block device on the metal lines so as to prevent a burning phenomenon from occurring during test of the liquid crystal panel.
The probe unit of claim 10, wherein the current block device is a diode and is formed on the electrode lines of the flexible printed circuit board along a direction of the panel.
The probe unit of claim 1, wherein the metal lines which are formed on the tab IC film mounted on the bottom surface of the body block have an interval therebetween which is adjusted to match an interval between the electrode liens of the liquid crystal panel.
The probe unit of claim 3, wherein among the metal lines formed on the tab IC film mounted on the bottom surface of the body block, metal lines that are in direct contact with the electrode lines of the liquid crystal panel not through a driver IC provided on the tab IC film are formed by etching on a metal plate.
The probe unit of claim 13, wherein the metal lines in direct contact with the electrode lines of the liquid crystal panel, not through the driver IC, are metal lines for providing electrical signals to a gate IC of the liquid crystal panel.
The probe unit of claim 1, wherein portions of the metal lines formed on tab IC film which are in contact with the liquid crystal panel are surface-processed with a high conductive material stable to thermal oxidation so as to prevent a burning phenomenon due to a high voltage generated when contacting with the electrode lines of the liquid crystal panel.
The probe unit of claim 1, wherein probe lead lines formed on the tab IC film mounted on the bottom surface of the body block are surface-processed with a high conductive material stable to thermal oxidation so as to prevent a burning phenomenon due to a high voltage generated when contacting with the electrode lines of the liquid crystal panel.
The probe unit of one of claims 15 and 16, wherein the high conductive material for surface-processing is gold (Au) or nickel (Ni).
The probe unit of claim 1, wherein among the metal lines formed on the tab IC film mounted on the bottom surface of the body block, metal lines that are in direct contact with the electrode lines of the liquid crystal panel not through a driver IC provided on the tab IC film are formed to be blade-tip type metal lines.