TWM564172U - Examining circuit for display panel - Google Patents

Abstract

An examining circuit for display panel includes a plurality of test pads and a plurality of switch devices. The plurality of test pads are disposed around an active region of the display panel and disposed between the active region and the plurality of switch devices. The test pads are respectively electrically connected to a plurality of signal lines in the active region, wherein plural test pads in the plurality of test pads are electrically connected to one of the plurality of switch devices, and the plural test pads, which are electrically connected to the one of the plurality of switch devices, provide signals to a plurality of pixels of the same color in the active region.

Description

Detection circuit of display panel

This novel creation is about a detection circuit, and particularly about a detection circuit for a display panel.

Generally speaking, before attaching the display panel to the back-end module (such as the backlight module), a signal of the P panel (Panel light-on inspection) is first input to the display panel to detect whether the display panel is a bit Or abnormal colors, etc., to clarify that the problem is caused by the array process, color filter or panel assembly process, and to screen out the defective products to avoid the waste caused by joining the defective products with the back-end module, and then cut costs.

In order to correspond to the P inspection tool, the terminal portion of the panel will be arranged with inspection circuits, such as a switch TFT group and a test pad, to correspond to the pin angle of the P inspection tool and the circuit design of the driving panel. Generally speaking, a gate line will be configured with a switching element (such as a thin film transistor) and a test pad, and a drain line will be configured with a switching element and a test pad. When designing the layout for the detection circuit, you often encounter a situation where the layout space is insufficient. The reason is that the layout space between the control switch group (corresponding to the location of the controller IC in FIG. 1) and the flexible printed circuit board FPC (see FIG. 1) is usually limited, and the number of switching elements in the control switch group It must correspond to the resolution supported by the Integrated Circuit (IC). When the resolution is higher, a larger layout space is required to set the switching element. In addition, in order to drive and control the switch group stably, the channel width and channel length of the thin film transistor must be limited, so the size and ratio of the thin film transistor cannot be arbitrarily reduced. Moreover, if the thin film transistor is too close to the adjacent thin film transistor, the interaction between the thin film transistors will affect the electrical properties, so the spacing between the thin film transistors cannot be arbitrarily reduced.

FIG. 1 is a schematic diagram of a conventional panel. FIG. 2 is a schematic diagram of a conventional shaped panel. Please refer to FIG. 1. Under the general panel structure, when the resolution is increased, the number of switching elements and test pads are increased. Since the layout space is unchanged, the size and spacing of the test pads (and thin film transistors) must be reduced to place more test pads (and thin film transistors). However, due to electrical requirements, thin-film transistors cannot be arbitrarily reduced in size and ratio. Therefore, the layout space of the control switch group is insufficient and the test pad and the thin-film transistor in the control switch group cannot be effectively connected. In addition, when the same resolution is applied to the special-shaped panel shown in FIG. 2, the terminal portion of the special-shaped panel is smaller than the general panel (compare the dotted circles on the left and right sides in FIGS. 1 and 2), so the above problem It will be more serious. If you sacrifice the confirmation check of P inspection, it will inevitably affect the process yield and risk. Therefore, there is a need to propose a detection circuit that is feasible under the above circumstances and does not reduce the benefits that the display panel can originally exert.

The novel creation provides a detection circuit for a display panel, which helps to improve the above problem of insufficient layout space.

The detection circuit of the display panel according to an embodiment of the present invention includes multiple test pads and multiple switching elements. A plurality of test pads are arranged around the active area of the display panel and between the active area and these switching elements. The test pads are electrically connected to a plurality of signal lines in the active area, wherein a plurality of test pads in the test pads are electrically connected to one of the switching elements, and are electrically connected to a plurality of tests of one of the switching elements The pad provides signals to multiple pixels of the same color in the active area.

Based on the above, in the detection circuit of the display panel of the embodiment of the present invention, by electrically connecting the test pads to the plurality of pixels of the same color in the active area, a plurality of test pads are electrically connected to one of the switches Components to greatly reduce the number of switching elements required, thereby reducing the layout space of the switching elements. Therefore, the detection circuit of the display panel of the embodiment of the present invention helps to solve the problem of insufficient layout space in the conventional art.

In order to make the above-mentioned features and advantages of the creation of the new model more obvious and understandable, the embodiments are specifically described below and described in detail in conjunction with the attached drawings.

FIG. 3 is a schematic top view of a detection circuit of a display panel according to an embodiment of the new creation. FIG. 4A is a schematic cross-sectional view of the second switching element created by the present invention. FIG. 4B is a schematic top view of the second switching element created by the present invention. FIG. 5 is a partially enlarged schematic diagram of FIG. 3. 6A to 6C are schematic cross-sectional views of regions A, B, and C in FIG. 5, respectively.

Please refer to FIG. 3. The detection circuit 100 of the display panel in this embodiment includes a plurality of test pads (such as a plurality of first test pads 112 and a plurality of second test pads 114) and a plurality of switching elements (such as a plurality of first switches Element 122 and a plurality of second switching elements 124). A plurality of test pads are arranged around the active area AR of the display panel 10, and the test pads are arranged between the active area AR and the switching elements. The test pads are electrically connected to a plurality of signal lines (such as a plurality of first signal lines SL1 and a plurality of second signal lines SL2) located in the active area AR, wherein a plurality of test pads in the test pads are electrically connected To one of the switching elements, and a plurality of test pads electrically connected to one of the switching elements provide signals to multiple pixels (such as multiple red pixels PR, multiple green pixels PG) of the same color in the active area AR Or multiple blue pixels PB). In other words, a plurality of test pads electrically connected to a plurality of pixels of the same color in the active area AR share one of the switching elements.

In detail, these test pads can be all disposed on one side of the active area AR of the display panel 10, but not limited to this. In another embodiment, the test pads may also be disposed on two adjacent sides, opposite sides, or three sides of the active area AR of the display panel 10. Alternatively, these test pads may be arranged around the active area AR.

Each first test pad 112 is electrically connected to one of the first signal lines SL1, and each second test pad 114 is electrically connected to one of the second signal lines SL2. In the display panel 10, the first signal line SL1 is, for example, a scanning line, and the second signal line SL2 is, for example, a data line. In other words, the first test pad 112 is a scan signal test pad, and the second test pad 114 is a data signal test pad. The scan signals can be input to the plurality of first signal lines SL1 in the display panel 10 through the plurality of first test pads 112, and the data signals can be input to the plurality of display panels 10 through the plurality of second test pads 114. A second signal line SL2.

In this embodiment, the first part P1 of the first test pads 112 and the second part P2 of the first test pads 112 are respectively disposed on opposite sides of the second test pads 114. In other words, the first test pads 112 inputting the scan signal are respectively disposed on opposite sides of the second test pads 114 inputting the data signal. In addition, the first part P1 in the first test pads 112 and the second part P2 in the first test pads 112 are electrically connected to different first signal lines SL1 respectively. For example, the first part P1 and the second part P2 may be electrically connected to the odd-numbered rows and the even-numbered rows of the first signal lines SL1, but not limited thereto. In another embodiment, the first part P1 and the second part P2 may be electrically connected to the first signal line SL1 in the upper half and the lower half, respectively.

Each first switch element 122 is electrically connected to one of the first test pads 112 respectively, and each second switch element 124 is electrically connected to the plurality of second test pads 114 among the second test pads 114. In other words, the plurality of second test pads 114 share one of the second switching elements 124. Generally speaking, the number of second signal lines SL2 (data lines) in the display panel 10 is usually greater than the number of first signal lines SL1 (scanning lines). In other words, the number of second test pads 114 electrically connected to the second signal line SL2 is greater than the number of first test pads 112 electrically connected to the first signal line SL1. Therefore, as compared with the plurality of first test pads 112 sharing one of the first switching elements 122, by the plurality of second test pads 114 sharing one of the second switching elements 124, the number of switching elements required can be reduced significantly . In this embodiment, the number of the first switching elements 122 connected to each first test pad 112 is one, but not limited to this. In another embodiment, a plurality of first test pads 112 may share one of the first switching elements 122 to further reduce the number of switching elements required.

When the connection relationship between the first switch element 122 and the first test pad 112 is one-to-one, the first switch element 122 can be a switch element of a conventional architecture. When the connection relationship between the first switch element 122 and the first test pad 112 is one-to-many (similar to the connection relationship between the second switch element 124 and the second test pad 122, the first switch element 122 may use the second switch element The architecture of the second switching element created by the novel is described below with reference to FIGS. 4A and 4B.

4A and 4B, each second switching element 124 may include a gate electrode GE, a drain electrode DE, a source electrode SE1, and a source electrode SE2. The gate electrode GE belongs to the first conductive layer M1, and the drain electrode DE, the source electrode SE1, and the source electrode SE2 belong to the second conductive layer M2. The first conductive layer M1 and the second conductive layer M2 are different layers, and the first conductive layer M1 and the second conductive layer M2 maintain independent electrical properties through the insulating layer IN1. It should be noted that FIG. 4B omits the drawing of the insulating layer IN1 in FIG. 4A to clearly show the gate electrode GE (first conductive layer M1) located under the insulating layer IN1. In addition, FIG. 4B also omits the drawing of the substrate SUB covered by the first conductive layer M1 in FIG. 4A.

3 and 5, the second test pads 114 include a plurality of red test pads 114R, a plurality of green test pads 114G, and a plurality of blue test pads 114B. These red test pads 114R provide red pixel drive signals to multiple red pixels PR located in the active area AR. These green test pads 114G provide green pixel driving signals to a plurality of green pixel PGs located in the active area AR. These blue test pads 114B provide blue pixel driving signals to a plurality of blue pixels PB located in the active area AR. In this embodiment, the red test pads 114R, the green test pads 114G, and the blue test pads 114B are alternately arranged between the active area AR and the second switching elements 124. Further, the arrangement direction of the red test pads 114R, the arrangement direction of the green test pads 114G, and the arrangement direction of the blue test pads 114B are respectively parallel to the adjacent red test pads 114R, the green tests in the active area AR Pad 114G and the sides of these blue test pads 114B. In this way, the layout space of the red test pad 114R, the green test pad 114G, and the blue test pad 114B in the extending direction of the first signal line SL1 can be further reduced.

These second switching elements 124 include a plurality of red switching elements 124R, a plurality of green switching elements 124G, and a plurality of blue switching elements 124B. Each red switching element 124R is electrically connected to a plurality of red test pads 114R. Each green switching element 124G is electrically connected to a plurality of green test pads 114G. Each blue switching element 124B is electrically connected to a plurality of blue test pads 114B. In this embodiment, each second switching element is electrically connected to two second test pads, but the creation of this new type is not limited to this. In an embodiment, each second switching element may be electrically connected to three, four, or more second test pads.

According to different requirements, the detection circuit 100 of the display panel may further include other elements. For example, the detection circuit 100 of the display panel may further include a plurality of wires 130. The wires 130 are connected between the first signal line SL1 and the first test pad 112, between the first test pad 112 and the first switching element 122, between the second signal line SL2 and the second test pad 114, and the second test Between the pad 114 and the second switching element 124, wherein the wires 130 connected between the second signal line SL2 and the second test pad 114 and the wires connected between the second test pad 114 and the second switching element 124 130 belongs to the second conductive layer or the third conductive layer, and the first conductive layer, the second conductive layer, and the third conductive layer are different layers. As shown in FIGS. 5 and 6A, at the area A, the wires 130R and the wires 130G belong to the second conductive layer M2, and the wires 130B belong to the third conductive layer M3, in which the second conductive layer M2 and the third conductive layer M3 pass The insulating layers IN2 each maintain independent electrical properties. As shown in FIGS. 5 and 6B (or FIG. 6C), at the area B (or area C), the wire 130R belongs to the second conductive layer M2, and the wire 130G belongs to the third conductive layer M3, in which the second conductive layer M2 and The third conductive layer M3 maintains independent electrical properties through the insulating layer IN2.

3 again, the detection circuit 100 of the display panel may further include a switch pad 140 and at least one gate signal pad 150 (FIG. 3 schematically shows two gate signal pads 150, but not limited thereto), The red signal pad 160, the green signal pad 170 and the blue signal pad 180. The switch pad 140 is electrically connected to the first switch elements 122 and the second switch elements 124. The gate signal pad 150 is electrically connected to the first switching elements 122. The red signal pad 160 is electrically connected to the plurality of red switch elements 124R electrically connected to the red test pads 114R among the second switch elements 124. The green signal pad 170 is electrically connected to the plurality of green switch elements 124G electrically connected to the green test pads 114G among the second switch elements 124. The blue signal pad 180 is electrically connected to the plurality of blue switching elements 124B electrically connected to the blue test pads 114B in the second switching elements 124.

During the p-test, the first switch element 122 and the second switch element 124 can be turned on by the switch pad 140. In addition, the gate signal pad 150 transmits the gate signal to the first switching elements 122. The gate signal is then transmitted through the first test pads 112 to the first signal lines SL1 in the active area AR. In addition, the red pixel driving signal is transmitted to the red switching elements 124R through the red signal pad 160. The red pixel driving signal is then transmitted to the red pixels PR in the active area AR through the red test pads 114R, so that the red pixels PR emit red light. The green signal pad 170 and the blue signal pad 180 can be deduced by analogy, which will not be repeated here.

In this embodiment, the layout of the second switching element 124 is the red switching element 124R, the green switching element 124G, and the blue switching element 124B. The layout of the second test pad 114 is the red test pad 114R, green The test pad 114G and the blue test pad 114B are sequentially arranged in parallel to the sides adjacent to the red test pad 114R, the green test pad 114G, and the blue test pad 114B in the active area AR, and the second switching element 124 is One-to-two, the closest way in the layout space is electrically connected to the second test pad 114 via the wire 130. But this new creation is not limited to the above. For example, the green switching element 124G, the red switching element 124R, and the blue switching element 124B may be arranged in sequence. In addition, the arrangement of the blue test pad 114B, the red test pad 114R, and the green test pad 114G between the active area AR and the second switching element 124 can be changed according to requirements. In addition, the second switching element 124 can have one-to-one and one-to-many combinations in the layout at the same time. However, it must be satisfied that the plurality of second test pads 114 sharing the same second switching element 124 are electrically connected to a plurality of pixels of the same color in the active area AR to avoid abnormal conditions such as color mixing.

In summary, in the detection circuit of the display panel of the embodiment of the present invention, the test pad is arranged around the active area of the display panel, which can effectively use the layout space. In addition, by electrically connecting a plurality of test pads among the test pads to one of the switching elements, the number of switching elements required can be greatly reduced, so the layout space of the switching elements can be greatly reduced. In addition, a plurality of test pads can adopt an array layout to further reduce the width of the horizontal layout. Furthermore, the detection circuit of the display panel can be adapted to the general manufacturing process and mask design of the display panel, so there is no need to increase the number of manufacturing channels and the number of masks.

Although the new creation has been disclosed as above with examples, it is not intended to limit the creation of the new creation. Anyone with ordinary knowledge in the technical field of the subject can make some changes and without departing from the spirit and scope of the new creation. Retouch, so the scope of protection of this new creation shall be subject to the scope defined in the appended patent application.

10‧‧‧Display panel
100‧‧‧Test circuit
112‧‧‧ First test pad
114‧‧‧ Second test pad
114B‧‧‧Blue test pad
114G‧‧‧Green test pad
114R‧‧‧Red test pad
122‧‧‧ First switching element
124‧‧‧Second switching element
124B‧‧‧Blue switching element
124G‧‧‧Green switching element
124R‧‧‧Red switching element
130, 130B, 130G, 130R‧‧‧ lead
140‧‧‧switch pad
150‧‧‧Gate signal pad
160‧‧‧Red signal pad
170‧‧‧ Green signal pad
180‧‧‧Blue signal pad
A, B, C
AR‧‧‧Active area
CH‧‧‧semiconductor layer
GE‧‧‧Gate
DE‧‧‧ Jiji
FPC‧‧‧flexible printed circuit board
IC‧‧‧Controller
IN1, IN2‧‧‧Insulation
M1‧‧‧ First conductive layer
M2‧‧‧Second conductive layer
M3‧‧‧third conductive layer
P1‧‧‧Part 1
P2‧‧‧Part 2
PB‧‧‧Blue pixel
PG‧‧‧Green pixel
PR‧‧‧Red pixel
SE1, SE2‧‧‧Source
SL1‧‧‧ First signal line
SL2‧‧‧Second signal line
SUB‧‧‧Substrate

FIG. 1 is a schematic diagram of a conventional panel. FIG. 2 is a schematic diagram of a conventional shaped panel. FIG. 3 is a schematic top view of a detection circuit of a display panel according to an embodiment of the new creation. FIG. 4A is a schematic cross-sectional view of the second switching element created by the present invention. FIG. 4B is a schematic top view of the second switching element created by the present invention. FIG. 5 is a partially enlarged schematic diagram of FIG. 3. 6A to 6C are schematic cross-sectional views of regions A, B, and C in FIG. 5, respectively.

Claims (10)

A detection circuit for a display panel includes: a plurality of test pads disposed around an active area of the display panel, and the test pads are electrically connected to a plurality of signal lines located in the active area; and a plurality of A switching element, wherein the test pads are disposed between the active area and the switching elements, the plurality of test pads in the test pads are electrically connected to one of the switching elements, and electrically connected to one of the switching elements The plurality of test pads provide signals to multiple pixels of the same color in the active area. The detection circuit of the display panel as described in item 1 of the patent application scope, wherein the test pads are all disposed on one side of the active area of the display panel. The detection circuit of the display panel as described in item 1 of the patent application scope, wherein the signal lines of the display panel include a plurality of first signal lines and a plurality of second signal lines, and the test pads include a plurality of first tests Pads and a plurality of second test pads, each of the first test pads is electrically connected to one of the first signal lines, each of the second test pads is electrically connected to one of the second signal lines, and the switching elements include a plurality of A first switching element and a plurality of second switching elements, each of the first switching elements is electrically connected to one of the first test pads, and each of the second switching elements is connected to the plurality of second test pads 2. The test pad is electrically connected. The detection circuit of the display panel as described in item 3 of the patent application scope, wherein the first signal lines are scanning lines, and the second signal lines are data lines. The detection circuit of the display panel as described in item 3 of the patent application scope, wherein a first part of the first test pads and a second part of the first test pads are respectively disposed on the second test pads On the opposite side, and the first part of the first test pads and the second part of the first test pads are electrically connected to different first signal lines, respectively. The detection circuit of the display panel according to item 3 of the patent application scope, wherein the second test pads include a plurality of red test pads, a plurality of green test pads, and a plurality of blue test pads, and the red test pads provide red The pixel drive signals to multiple red pixels in the active area, the green test pads provide green pixel drive signals to multiple green pixels in the active area, and the blue test pads provide blue The pixel driving signal is to a plurality of blue pixels in the active area, and the red test pads, the green test pads and the blue test pads are alternately arranged in the active area and the second switching elements between. The detection circuit of the display panel as described in Item 6 of the patent application range, wherein the arrangement direction of the red test pads, the arrangement direction of the green test pads, and the arrangement direction of the blue test pads are respectively parallel to the active area Is adjacent to the sides of the red test pads, the green test pads, and the blue test pads. The detection circuit of the display panel as described in item 3 of the patent application, wherein each of the second switching elements includes a gate, a drain and two sources, the gate belongs to a first conductive layer, the drain And the two source electrodes belong to a second conductive layer, and the first conductive layer and the second conductive layer are different layers. The detection circuit of the display panel as described in item 8 of the patent application scope further includes: a plurality of wires connected between the first signal lines and the first test pads, the first test pads and the some Between the first switching elements, between the second signal lines and the second test pads, and between the second test pads and the second switching elements, wherein the second signal lines and the second switching elements are connected The wires between the second test pads and the wires connected between the second test pads and the second switching elements belong to the second conductive layer or a third conductive layer, and the first The conductive layer, the second conductive layer and the third conductive layer are different layers. The detection circuit of the display panel as described in item 9 of the patent application range, wherein the second test pads include a plurality of red test pads, a plurality of green test pads, and a plurality of blue test pads, the red test pads provide red The pixel drive signals to multiple red pixels in the active area, the green test pads provide green pixel drive signals to multiple green pixels in the active area, and the blue test pads provide blue The pixel driving signal is to a plurality of blue pixels located in the active area, and the detection circuit of the display panel further includes: a switch pad electrically connected to the first switching elements and the second switching elements; at least A gate signal pad electrically connected to the first switch elements; a red signal pad electrically connected to the plurality of red switch elements electrically connected to the red test pads in the second switch elements; a A green signal pad electrically connected to the plurality of green switch elements electrically connected to the green test pads among the second switch elements; and a blue signal pad electrically connected to the second switches Test member with a plurality of the plurality of blue blue pad electrically connected to the switching element.