Panel module and manufacturing method thereof

A panel module is provided, including a first substrate, a second substrate, a first optical glue, and a second optical glue. The first and second optical glues are disposed between the first and second substrates, wherein the first optical glue protrudes from the first substrate, and the second optical glue adheres the first substrate to the second substrate. Specifically, the viscosity of the second optical glue is smaller than the first optical glue before solidification.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This application relates in general to a panel module and in particular to a panel module with two substrates having a constant distance therebetween.

2. Description of the Related Art

Referring toFIGS. 1A and 1B, a conventional touch panel usually comprises a first substrate11and a second substrate12. During assembly, an LOCA13(liquid optical clear glue) is disposed between the first and second substrates11and12and cured by UV light, so as to firmly connect the first substrate11with the second substrate12.

However, since the LOCA13can flow and form an uneven surface, an air gap131may be formed between the first and second substrates11and12. Thus, bending and deformation of the first and second substrates11and12may occur and lead to a non-uniform distance therebetween. Generally, the distance between the first and second substrates11and12near the center thereof is smaller than that near the edge thereof. In practical applications, such as in the production of 3.5 inches touch panels, the variation of the distance may exceed 30%.

In capacitive touch panels, non-uniform distances between the first and second substrates11and12can adversely affect accuracy of capacitance sensing. For the reasons described above, the task of preventing non-uniform distances from occurring between the first and second substrates during assembly, has become a challenge.

BRIEF SUMMARY OF INVENTION

An embodiment of the invention provides a panel module including a first substrate, a second substrate, a first optical glue, and a second optical glue. The first and second optical glues are disposed between the first and second substrates, wherein the first optical glue protrudes from the first substrate, and the second optical glue adheres the first substrate to the second substrate. Specifically, the viscosity of the second optical glue is smaller than the first optical glue before solidification.

Additionally, an embodiment of the invention provides a method for manufacturing a panel module, comprising the steps of: disposing a first optical glue on a first substrate, wherein the first optical glue is located near a center of the panel module and protrudes from the first substrate; solidifying the first optical glue; disposing a second optical glue on a first substrate; disposing a second substrate on the first substrate; and solidifying the second optical glue to adhere the second substrate to the first substrate.

DETAILED DESCRIPTION OF INVENTION

Referring toFIG. 2, an embodiment of a panel module20may be a touch panel module of an electronic device. The panel module20primarily comprises a first substrate21and a second substrate22. Specifically, at least a first optical glue G1, a second optical glue G2, and at least a dam D are disposed between the first and second substrates21and22. In this embodiment, the first optical glue G1, the second optical glue G2, and the dam D may comprise UV curable material, wherein the viscosity of the first optical glue G1and the dam D is from 10000 to 40000 cps/25° C. before solidification, and the viscosity of the second optical glue G2is from 1000 to 3000 cps/25° C. before solidification. Namely, the viscosity of the second optical glue G2is substantially smaller than that of the first optical glue G1and the dam D before solidification.

During assembly of the panel module20, first, a plurality of first optical glues G1and the dam D are disposed on the first substrate21. After the first optical glues G1and the dam D are solidified, the second optical glue G2is disposed on the first substrate21. Subsequently, the second optical glue G2is solidified to firmly connect the first and second substrates21and22together.

In this embodiment, the dam D and the first and second optical glues G1and G2can be cured by UV light, wherein the heights of the first optical glue G1and the dam D are substantially the same. Since the second optical glue G2can be filled into the gaps between the first optical glues G1and the dam D, the first and second substrates21and22are firmly connected. As shown inFIG. 2, each of the first optical glues G1has a round structure contacting with the first and second substrates21and22. It is noted that the first optical glues G1are spaced apart from each other, to suppress the second optical glue G2from flowing on the first substrate21. Thus, bending or deformation of the first and second substrates21and22can be prevented during assembly, so as to ensure quality of the panel module20.

Referring toFIG. 3, the first optical glues G1can be disposed near a center of the panel module20, arranged in a dot matrix pattern, and surrounded by the dams D. In this embodiment, the dams D are substantially longitudinal and near the edges of the panel module20. As shown inFIG. 3, the adjacent dams D form a vent hole V therebetween for discharging the second optical glue G2before solidification.

Referring toFIG. 4, the first optical glue G1protrudes from the first substrate21, but does not contact the second substrate22. In this configuration, the first and second substrates21and22are structurally supported by the dam D and spaced apart from each other at a distance, wherein the first optical glue G1is encompassed by the second optical glue G2. As shown inFIG. 4, the height h of the first optical glue G1is smaller than the height H of the second optical glue G2. Since the first optical glue G1protrudes from the first substrate21, the flow of the second optical glue G2on the first substrate21can be suppressed, so as to prevent bending or deformation of the first and second substrates21and22and ensure quality of the panel module20.

In some embodiments, the first optical glues G1may form a plurality of protruding structures with different heights on the first substrate21, as shown inFIG. 5, wherein the protruding structures decrease progressively from the center to the edges of the panel module20. Since the viscosity of the second optical glue G2is smaller than that of the first optical glue G1before solidification, the protruding structures of the first optical glues G1can suppress the second optical glue G2from flowing on the first substrate21, so as to prevent bending or deformation of the first and second substrates21and22.

Referring toFIG. 6, another embodiment of a panel module30is a multi-layer touch panel module, comprising a first substrate31, a second substrate32, and a third substrate33. As shown inFIG. 6, the dams D are disposed between first, second, and third substrates31,32, and33. Specifically, the first optical glues G1form a plurality of protruding structures on the first and second substrates31and32, wherein the heights of the protruding structures can be the same or different. When the first optical glues G1are solidified, the second optical glue G2can be filled into the space between the first, second, and third substrates31,32, and33, so as to firmly connect the first substrate31with the second substrate32.

Referring toFIGS. 7-9, the first optical glues G1can be disposed near a center of the panel module20and arranged to form various patterns on the first substrate21. As shown inFIG. 7, the first optical glues G1are neatly and uniformly arranged in a dot matrix pattern. As shown inFIG. 8, the first optical glues G1are substantially longitudinal and arranged in parallel, wherein the widths of the first optical glues G1may be the same or different. As shown inFIG. 9, the first optical glues G1are substantially longitudinal and arranged to form a maze structure in the panel module.

The invention provides a panel module including a first substrate and a second substrate with a first optical glue and a second optical glue disposed therebetween. In some embodiments, a plurality of first optical glues is arranged in a dot matrix pattern on the first substrate, and the second optical glue is applied to firmly connect the first substrate with the second substrate. Specifically, the viscosity of the second optical glue is smaller than that of the first optical glue before solidification. Thus, bending or deformation of the first and second substrates can be prevented during assembly, so as to keep a constant distance therebetween and ensure quality of the panel module.