CN116984746A - Laser etching system and method for patterning electrode layer - Google Patents

Abstract

The invention discloses a laser etching system for electrode layer patterning, which can not damage a conductive layer on a second surface of a substrate when the conductive layer on the first surface of the substrate of a touch panel with a double-sided structure is patterned by using a laser beam. Wherein the laser etching system further comprises an optical element that makes a ratio of a spot area of the laser beam irradiated at the second surface to a spot area irradiated at the first surface not less than 1.2. The invention also discloses a laser etching method for patterning the electrode layer, which realizes the patterning of the electrode layer of the touch panel with the double-sided structure by applying the laser etching system for patterning the electrode layer.

Description

Laser etching system and method for patterning electrode layer

Technical Field

The invention relates to the technical field of touch screens, in particular to a laser etching system and method for patterning an electrode layer.

Background

Touch screens (touch screens) are currently the simplest, convenient and natural man-machine interaction mode, and are widely applied to various fields such as information inquiry, industrial control, self-service, multimedia teaching, electronic games and the like. Among various touch screen types, the capacitive touch screen occupies an important position and has better application prospect due to the advantages of accuracy, good use, abrasion resistance, long service life and the like. In general, a capacitive touch screen includes a touch panel and a display screen fixedly connected to each other at their edge portions by an adhesive member (e.g., double-sided tape, adhesive, etc.), wherein the touch panel is a screen portion providing a touch function and the display screen is a screen portion providing a display function.

The touch panel can be of a single-sided structure or a double-sided structure, and only the touch panel of the double-sided structure is involved in the invention. In the prior art, as shown in fig. 1, a touch panel 1 of a double-sided structure using the concept of mutual capacitance has a generally transparent substrate, which is, for example, glass or PET material. On one surface (the front surface in fig. 1, i.e., the surface facing the outside of the paper surface) of the substrate, a plurality of rows of sequentially arranged drive conductive lines, such as drive conductive lines 20, which form the drive electrode layer of the touch panel 1 of the double-sided structure; and on the other surface (the back surface in fig. 1, i.e., the surface facing the inside of the paper, the structures arranged on the back surface are all shown by dotted lines) there are a plurality of columns of sequentially arranged sensing conductive lines, such as sensing conductive line 10, which form the sensing electrode layer of the touch panel 1 of the double-sided structure. That is, two electrode layers, i.e., a driving electrode layer and a sensing electrode layer, are formed on both surfaces of a substrate of a touch panel having a double-sided structure, and generally, this is obtained by forming conductive layers of a material such as ITO, IGZO, PEDOT, nano silver wires, metal mesh, etc., on both surfaces of the substrate, and patterning the conductive layers.

Patterning of electrode layers of a touch panel of a double-sided structure is generally performed by an industry conventional process such as a yellow light process, a dry process (i.e., using etching paste), but a laser process suitable for a touch panel of a single-sided structure, in which an electrode layer is formed only on one surface of a substrate, cannot be applied, because when patterning a conductive layer on one surface of a substrate by applying laser to form an electrode layer, the laser penetrates the substrate (which has a very thin thickness, typically between 0.3 and 1.1 mm), and undesirably patterns the formed electrode layer or conductive layer on the other surface of the substrate, thereby affecting the touch function of the touch panel product.

However, the yellow light process and the dry process have the problems of complex process, high cost and environmental pollution, which are unfavorable for energy conservation and emission reduction, while the laser process has the advantages of simple process, high manufacturing precision, accurate and controllable performance, low cost and no environmental pollution, so how to apply the laser process to the patterning of the electrode layer of the touch panel with the double-sided structure has become a subject of urgent development breakthrough in the touch industry.

Accordingly, those skilled in the art have been directed to developing a laser etching system and method for patterning an electrode layer, which is suitable for patterning an electrode layer of a touch panel of a double-sided structure, thereby solving the above-mentioned technical problems.

Disclosure of Invention

To achieve the above object, the present invention provides, in one aspect, a laser etching system for electrode layer patterning capable of patterning a conductive layer on a first surface of a substrate of a touch panel of a double-sided structure with a laser beam without damaging the conductive layer on a second surface of the substrate, comprising:

a laser for generating and emitting the laser beam;

the laser etching platform is used for bearing and fixing the substrate of the touch panel, so that the first surface faces the laser beam, and the second surface is attached to the laser etching platform;

wherein the laser etching system further comprises an optical element that makes a ratio of a spot area of the laser beam irradiated at the second surface to a spot area irradiated at the first surface not less than 1.2.

Further alternatively, the ratio of the area of the spot irradiated by the laser beam at the second surface to the area of the spot irradiated at the first surface is 1.2-20.

Further alternatively, the ratio of the area of the spot irradiated at the second surface to the area of the spot irradiated at the first surface by the laser beam is not less than 1.5.

Further alternatively, a ratio of a spot area of the laser beam irradiated at the second surface to a spot area irradiated at the first surface is not less than 1.8.

Further alternatively, a ratio of a spot area of the laser beam irradiated at the second surface to a spot area irradiated at the first surface is not less than 2.

Optionally, the laser beam is a plurality of laser beams, the spots of the plurality of laser beams irradiated at the first surface coincide, and the spots irradiated at the second surface are separated from each other.

Further, at least one of the laser beams is incident on the first surface at an angle of less than 90 ° relative to the first surface.

Further, at least one of the laser beams is incident on the first surface at an angle of no more than 60 ° relative to the first surface.

Further, at least part of the optical element is implemented as a laser galvanometer.

Optionally, the optical element further comprises a lens that causes the laser beam passing therethrough to be formed as a positive defocus laser beam focused outside the substrate, the positive defocus laser beam having a larger spot area at the second surface than at the first surface.

Further, the angle of incidence of the laser beam on the first surface is less than 90 degrees relative to the first surface.

Further, the angle of incidence of the laser beam on the first surface is not greater than 60 degrees relative to the first surface.

Further, the laser beam is a plurality of laser beams whose spots irradiated at the first surface coincide and spots irradiated at the second surface are separated from each other.

Further optionally, the laser etching system has a plurality of lasers, the plurality of laser beams respectively reaching the plurality of lasers.

Further alternatively, at least two laser beams of the plurality of laser beams are formed by splitting a laser beam from one laser via a beam splitter.

Further, the laser etching system further comprises a blowing device for providing a flow of cooling gas to the laser beam at the spot location of the first surface.

Further, the blowing device uses liquid nitrogen as a cooling source to provide the cooling gas flow.

Further, the laser etching system further comprises cooling means for providing a coolant flow to the laser beam at the spot location of the second surface, wherein the temperature of the coolant flow is at least 14 ℃ lower than the temperature of the cooling gas flow.

Further, the cooling device employs solid nitrogen as a cooling source to provide the coolant flow.

Further, a surface of the laser etching stage that is in contact with the second surface of the substrate is formed with at least one recess that is disposed adjacent to a spot location of the laser beam that impinges on the second surface, and the coolant flow is introduced into the recess to provide cooling at the spot location of the laser beam that impinges on the second surface.

Further, the cooling device is a cooling circulation device connected to the recess via a coolant inlet duct and a coolant return duct, the coolant flow from the cooling device entering the recess through the coolant inlet duct and then returning to the cooling device through the coolant return duct.

The present invention provides in a second aspect a laser etching method for patterning an electrode layer, comprising: with the laser etching system for electrode layer patterning of the present invention as described above, the optical element is arranged such that the ratio of the spot area of the laser beam irradiated at the second surface to the spot area irradiated at the first surface is not less than 1.2, and then the electrode layer patterning is performed on the conductive layer on the first surface of the substrate with the laser beam.

Therefore, the laser etching system and the method for patterning the electrode layer adopt the laser beam to irradiate the touch panel with the double-sided structure to be etched, so that the ratio of the area of a light spot irradiated by the laser beam on the second surface of the substrate to the area of the light spot irradiated by the laser beam on the first surface of the substrate is not less than 1.2, the energy density of the laser beam irradiated by the second surface is obviously reduced, and the damage of the laser beam to the conductive layer on the second surface in the process of patterning the conductive layer on the first surface is avoided. In addition, the laser etching system and method for patterning an electrode layer of the present invention employs a blowing device to provide a flow of cooling gas to a spot position of a laser beam irradiated on a first surface to cool a temperature at the spot position and to take away a portion of a conductive layer removed by laser etching; the laser etching system and method for patterning an electrode layer of the present invention also employs a cooling device that provides a coolant flow at a temperature lower than the coolant gas flow to the spot location of the laser beam on the second surface, thereby further protecting the conductive layer on the second surface of the substrate from damage by the laser beam. Therefore, the laser etching system and the method for patterning the electrode layer can be used for the touch panel with the double-sided structure, wherein the conductive layer on the other surface is not damaged when the conductive layer on one surface of the substrate of the touch panel is etched by the laser beam, so that the electrode layer patterning of the touch panel with the double-sided structure is realized by applying a laser process.

The conception, specific structure, and technical effects of the present invention will be further described with reference to the accompanying drawings to fully understand the objects, features, and effects of the present invention.

Drawings

Fig. 1 schematically shows a touch panel of a double-sided structure.

Fig. 2 shows a schematic diagram of a laser etching system for patterning an electrode layer according to the present invention, which is used to pattern a conductive layer on an upper surface of a touch panel with a double-sided structure.

Fig. 3 is a structure of the laser etching system for patterning an electrode layer shown in fig. 2.

Fig. 4 schematically shows a laser beam used to pattern an electrode layer of a touch panel of a double-sided structure in the embodiment shown in fig. 2.

Fig. 5 schematically illustrates a laser beam used to pattern an electrode layer of a touch panel of a double-sided structure in another preferred embodiment.

Fig. 6 schematically illustrates a laser beam used to pattern an electrode layer of a touch panel of a double-sided structure in another preferred embodiment.

Fig. 7 schematically illustrates a laser beam used to pattern an electrode layer of a touch panel of a double-sided structure in another preferred embodiment.

Detailed Description

In a preferred embodiment, as shown in fig. 2-4, the present invention provides a laser etching system 100 for patterning electrode layers, which is suitable for patterning electrode layers of a touch panel of a double-sided structure. In the present embodiment, the laser etching system 100 includes a laser 110, a laser etching stage 120, an air blowing device 130, and a cooling device 140, and patterns (i.e., etches) the conductive layer on the surface of the substrate 12 of the touch panel 1 with a double-sided structure to form a desired electrode layer.

Specifically, laser 110 generates and emits a laser beam a for patterning the electrode layer, which can be focused to a suitable beam spot size (which is generally related to the resolution of the desired pattern) and directed to impinge on the region of the conductive layer to be patterned, the focused laser beam having a suitable energy to etch away unwanted portions of the conductive layer leaving portions of the conductive layer having the desired pattern.

The laser beam a emitted from the laser 110 passes through a plurality of optical elements and irradiates the substrate 12 on the laser etching stage 120. These optical elements may include optical elements for directing, focusing, adjusting the beam diameter, adjusting the angle of incidence, adjusting the intensity, converging or diverging the like of the laser beam a, such as beam expanders, refractors, laser galvanometers, field mirrors, etc. In this embodiment, an optical element implemented as a laser galvanometer 111 (for example, a scanning galvanometer of scanlab, a johner galvanometer, or the like may be employed) is used to adjust the optical path of the laser beam a so that it can be irradiated to the region of the conductive layer to be etched; the laser beam a is formed as a positive defocus laser beam by an optical element such as a lens 112 (i.e., the laser beam a whose laser focal point is above the region of the conductive layer to be etched, as shown in fig. 4. The lens 112 may be a lens integrated in the laser galvanometer 111 or may be an additionally provided lens in this embodiment, the laser beam a is formed as a positive defocus laser beam by the lens 112 in the laser galvanometer 111. They are separately drawn for clarity of illustration only. In addition, optical elements such as a beam expander, a refractor, a laser galvanometer, a field lens, etc. disposed on the optical path of the laser beam a are omitted for clarity of illustration as well.

Thus, by the optical element described above, the area S2 of the spot formed at the lower surface of the substrate 12 irradiated with the laser beam a will be larger than the area S1 of the spot formed at the upper surface of the substrate 12 irradiated with the laser beam a, thereby reducing the energy density of the laser beam a at the lower surface of the substrate 12 without damaging the conductive layer of the lower surface of the substrate 12 easily. Preferably, spot area S2 is 1.2-20 times spot area S1.

The laser etching stage 120 is capable of carrying, fixing the touch panel 1 during the laser etching process, so that the relative movement between the laser beam a and the touch panel 1 during the laser etching process is achieved by its own relative movement with respect to the laser beam a (e.g. controlled movement of the laser etching stage 120, or controlled movement of the guiding means of the laser beam a (e.g. the optical elements described above), or both), so that the laser beam a can sequentially irradiate the areas of the conductive layer on the touch panel that need to be patterned for etching.

In this embodiment, the laser etching platform 120 fixes the touch panel 1 by means of negative pressure adsorption, as shown in fig. 3, the surface (upper surface shown in the drawing) of the laser etching platform 120 for carrying the touch panel 1 has a plurality of vacuum adsorption holes 123, which are communicated with an internal chamber in the laser etching platform 120, and the internal chamber forms an internal negative pressure by an external air pump (not shown), so that when the touch panel 1 is placed on the upper surface of the laser etching platform 120, the internal chamber of the negative pressure will generate a downward adsorption force to the touch panel 1 through the vacuum adsorption holes 123, thereby firmly adsorbing the touch panel 1 on the laser etching platform 120.

The blowing means 130 has at least one blowing port for blowing a flow of cooling gas B, such as a cooled air flow, to the portion of the conductive layer being laser etched on the touch panel 1 during the laser etching, thereby removing heat and conductive layer residues generated by the laser etching. In this embodiment, the gas blowing port of the gas blowing device 130 can be automatically aligned with the position of the laser etching, for example, by the controller of the gas blowing device 130 itself or by the controller of the laser etching system 100, so as to precisely blow the cooling gas flow B to the position.

The cooling device 140 is used to provide a coolant flow, such as a cooled water flow, to the laser etching platform 120, the coolant flow having a temperature lower than the temperature of the cooling gas flow, thereby providing further cooling to the touch panel 1, and in particular the lower surface thereof, during the laser etching process. Specifically, the upper surface of the laser etching stage 120 has at least one (four are shown in fig. 3) recess 122, and the recess 122 is located so as to be adjacent to a region of the lower surface of the touch panel 1 fixed on the laser etching stage 120, which is likely to be laser-etched, that is, a location region where the laser beam a will be irradiated to the lower surface thereof through the substrate 12. Typically, the recess 122 is located at a middle portion of the upper surface of the laser etching stage 120, and the aforementioned vacuum suction holes 123 are distributed around the recess 122. Preferably, the depth of the recess 122 is no greater than 5cm.

At least one coolant inlet 1241 and at least one coolant outlet 1242 are provided in each recess 122, whereby the coolant inlet flow C1 from the cooling device 140 will enter the recess 123 through the respective coolant inlet duct 1211 and coolant inlet 1241, cool the area on the lower surface of the adjacent touch panel 1, and then return to the cooling device 140 as coolant return flow C2 through the respective coolant outlet 1242 and coolant return duct 1212. In the present embodiment, the coolant inlet 1241 in one recess 122 corresponds to one coolant inlet duct 1211, and the coolant outlet 1242 in one recess 122 corresponds to one coolant return duct 1212. In this way, the recess 122 to which the coolant is to be input can be selected according to the area on the touch panel 1 being laser etched, and the valves of its corresponding coolant inlet duct 1211 and coolant return duct 1212 are opened so that the coolant circulates between the cooling device 140 and the selected recess 122 only through the coolant inlet duct 1211 and coolant return duct 1212 and the corresponding coolant inlet 1241 and coolant outlet 1242, thereby saving the consumption of the coolant.

As described above, the cooling device 140 employed in the present embodiment is a cooling circulation device, thereby contributing to energy saving. Those skilled in the art will appreciate that in other embodiments, the cooling device 140 may be a single function coolant source that provides only the coolant inlet stream and does not receive the coolant return stream. At this time, a device may be additionally provided to receive the coolant return flow.

In using the laser etching system 100 for electrode layer patterning of the present invention, the substrate 12 of the touch panel 1 of a double-sided structure is first placed on the laser etching stage 120, as shown in fig. 2. The substrate 12 is firmly adsorbed onto the upper surface of the laser etching stage 120 by the external air pump.

As shown in fig. 4, both surfaces of the substrate 12 are formed with conductive layers, wherein an upper surface (i.e., the upward facing surface shown in fig. 2, 4, which faces away from the laser etching stage 120) is formed with a conductive layer 13, and a lower surface (i.e., the downward facing surface shown in fig. 2, 4, which faces toward and is adhered to the laser etching stage 120) of the substrate 12 is formed with a conductive layer 14. Here, the conductive layer 13 on the upper surface of the substrate 12 is subjected to laser etching, and the conductive layer 14 may be a conductive layer which has not been subjected to laser etching, or may be an electrode layer which has been formed by laser etching.

Next, the operating parameters of the laser 110 are set, and the optical path of the laser beam a emitted from the laser 110 is adjusted by the laser galvanometer 111 so that it can irradiate the conductive layer region to be etched on the upper surface of the substrate 12 with an appropriate spot size and energy density. This step may be done before or simultaneously with the placement and fixing of the touch panel 1.

In this embodiment, a 1064nm laser is used, the frequency of the laser galvanometer 111 is set to 300-500KHz, the scanning speed is 2000-3000mm/S, and 32% of the 30 watt laser is set for etching (in other embodiments, the laser power may be 20-30 watt, and 10% -50% is set for etching), so as to avoid the possibility of damaging the conductive layer on the lower surface of the substrate 12 with too high laser power. In addition, in the present embodiment, the conductive layer on the surface of the etched substrate 12 is irradiated with a laser beam a that is perpendicularly incident (i.e., the angle of the laser beam a with respect to the surface of the substrate 12 is 90 °), and the focal position of the laser beam a above the substrate 12 is set so that the spot area S2 formed at the lower surface of the substrate 12 is 1.5 to 5 times the spot area S1 formed at the upper surface of the substrate 12. In other embodiments, spot area S2 may be set to be no less than 1.2 times, 1.5 times, 1.8 times, 2 times, and/or no greater than 20 times spot area S1.

Next, the operating parameters of the blowing device 130 are set, including the temperature and flow rate of the cooling gas flow B blown out thereof. Also, this step may be performed before or simultaneously with the aforementioned steps.

In this embodiment, liquid nitrogen is used as a cooling source of the blower 130, and air cooled by the liquid nitrogen is blown out by the blower 130 to form a cooling gas flow B having a temperature of between-196 ℃ and 30 ℃ and a flow rate of 0.5m/s to 30m/s.

Next, the operating parameters of the cooling device 140 are set, including the temperature and flow rate of the coolant it provides, and the valves of the coolant inlet conduit 1211 and the coolant return conduit 1212 that need to be opened. Also, this step may be performed before or simultaneously with the aforementioned steps.

In this embodiment, solid nitrogen is used as the cooling source for the coolant, and a liquid (e.g., water) cooled by the solid nitrogen is delivered by the cooling device 140 to the selected recess or recesses 122 on the laser etching stage 120, the delivered coolant inlet stream C1 having a temperature between-210℃ and 30℃ and a flow rate of 0.5m/s-30m/s.

After the above-mentioned arrangement is completed, the laser 110, the blower 130 and the cooling device 140 may be turned on, and patterning, i.e. laser etching, of the conductive layer 13 on the upper surface of the substrate 12 of the touch panel 1 may be started. Specifically, the laser beam a emitted from the laser 110 is directed to irradiate the conductive layer 13, and the conductive layer 13 is patterned according to a predetermined pattern, and a portion of the conductive layer 13 is etched away. Wherein the air blowing port of the air blowing device 130 is automatically aligned to the position of the laser etching position, so that the heat of the upper surface of the substrate 12 is quickly blown away, and the adverse effect of the laser energy on the conductive layer 14 of the lower surface of the substrate 12 is reduced. At the same time, the cooling device 140 provides a circulating flow of coolant to rapidly remove heat generated by the laser light irradiated through the substrate 12 to the conductive layer 14 on the lower surface thereof, so as not to damage the conductive layer 14 on the lower surface of the substrate 12.

Since the laser beam a is formed as a positive defocus laser beam whose ratio of the spot area S2 formed at the lower surface of the substrate 12 to the spot area S1 formed at the upper surface of the substrate 12 is not less than 1.2, and since the temperature of the coolant flow C1 flowing in the vicinity of the lower surface of the substrate 12 is lower than the temperature of the cooling gas flow B flowing in the vicinity of the upper surface of the substrate 12, the laser beam a can remove a portion of the conductive layer 13 of the upper surface of the substrate 12 without affecting the conductive layer 14 of the lower surface of the substrate 12 by normal etching. Thus, a conductive layer portion (e.g., conductive layer portion 11 in fig. 2) having a desired pattern is finally left on the upper surface of the substrate 12, forming a desired electrode layer.

In addition, in other embodiments, the spot formed on the lower surface of the substrate 12 may be further irradiated with the laser beam a by adjusting the incident angle θ of the laser beam a with respect to the surface of the substrate 12, thereby obtaining a lower surface spot area S2 that is larger with respect to the upper surface spot area S1, as shown in fig. 5. Wherein, for clarity and convenience of illustration, refraction of obliquely incident laser beams in the substrate is not depicted in fig. 5 and thereafter in fig. 6 and 7.

At this time, the incident angle θ of the laser beam a is smaller than 90 °, and as the incident angle θ decreases, the ratio of the lower surface spot area S2 to the upper surface spot area S1 will increase, thereby decreasing the energy density of the laser beam a at the lower surface of the substrate 12. Preferably, the incident angle θ is no greater than 60 °. By adjusting the incidence angle θ, it is possible to realize that the spot area S2 of the laser beam a formed at the lower surface of the substrate 12 is 1.5 to 10 times the spot area S1 thereof formed at the upper surface of the substrate 12. In other embodiments, spot area S2 may be set to be no less than 1.2 times, 1.5 times, 1.8 times, 2 times, and/or no greater than 20 times spot area S1.

As shown in fig. 6 and 7, the substrate 12 of the touch panel 1 may be irradiated with a plurality of (two in the drawing) laser beams A1 and A2. The two laser beams A1, A2 may come from two lasers as shown in fig. 6; the laser beam a from one laser may be formed by splitting it by the beam splitter 113, as shown in fig. 7. The two laser beams A1, A2 are focused into positive defocus laser beams by respective lenses 1121, 1122, respectively, and are irradiated to the conductive layer 13 on the upper surface of the substrate 12 at respective incident angles θ1, θ2, and the spots of the two laser beams A1, A2 at the upper surface conductive layer 13 coincide with each other in spot area S1, and are separated at the lower surface conductive layer 14 in spot areas S21, S22, respectively, whereby the lower surface spot area s2=s21+s22. This may allow a further increase in the ratio of the lower surface spot area S2 to the upper surface spot area S1, e.g. the spot area S2 formed by the laser beams A1, A2 at the lower surface of the substrate 12 is 1.5-20 times the spot area S1 formed by it at the upper surface of the substrate 12. In other embodiments, spot area S2 may be set to be no less than 1.2 times, 1.5 times, 1.8 times, 2 times, and/or no greater than 20 times spot area S1. In addition, the ratio can be further increased by decreasing the incident angles θ1, θ2.

Since in both embodiments shown in fig. 6, 7 the spots of the two laser beams A1, A2 coincide at the upper surface of the substrate 12, the laser energy density experienced at the etched location where the upper surface conductive layer 13 is etched is the sum of the energy densities of the two laser beams at that location, so that the two laser beams A1, A2 should have a lower energy density than the laser beam a in the embodiment shown in fig. 5. For example, when the incident angles are the same, the energy density of the laser beams A1, A2 in the embodiment shown in fig. 6 may be half that of the laser beam a in the embodiment shown in fig. 5. For another example, when the incident angles are the same, the laser beams A1 and A2 in the embodiment shown in fig. 6 may be formed by splitting the laser beam a in the embodiment shown in fig. 5 by an optical element such as the beam splitter 113.

It should be noted that, as described above, the optical element commonly used in the art for adjusting the optical path of the laser beam so as to be capable of irradiating the region of the conductive layer to be etched is implemented as a laser galvanometer, and therefore when etching the conductive layer on the upper surface using two or more laser beams as described above, it is necessary to appropriately set parameters of the laser galvanometers for the laser beams respectively so as to be capable of cooperating, and keep the spots of the laser beams on the upper surface overlapping and the spots on the lower surface separating during the scanning etching of the conductive layer on the upper surface.

Alternatively, it is also possible to make these laser galvanometers free of scanning operations, i.e. to keep their optical scanning head stationary with respect to, for example, the laser during etching, while the laser beam is driven to effect etching of the conductive layer areas to be etched in turn by the laser beam. This approach can simplify the setup of the laser galvanometer, but in general, the manner in which the movement of the laser etching stage is achieved by the setup of the motor is inferior in accuracy and speed to the laser galvanometer.

In addition, it will be appreciated by those skilled in the art that although the above description is given of how to use a plurality of laser beams to pattern a conductive layer on one surface (first surface) of a substrate of a touch panel of a double-sided structure without damaging the conductive layer on the other surface (second surface) by taking two obliquely incident positive defocus laser beams as an example, it is also possible to allow one of the laser beams to be perpendicularly incident by appropriately adjusting (for example, by an optical element such as a diaphragm, a lens, or the like) the spot size of the laser beam on the first surface. Moreover, as will be appreciated by those skilled in the art, in achieving the above-described object using a plurality of laser beams, it is not necessarily required to employ a positive defocus laser beam, and as long as the plurality of laser beams overlap in light spots on the first surface and are separated in light spots on the second surface, it is possible to ensure that the energy density of the laser beam at the light spots on the first surface is greater than the energy density at the light spots on the second surface, so that the conductive layer on the first surface can be etched without damaging the conductive layer on the second surface.

The foregoing describes in detail preferred embodiments of the present invention. It should be understood that numerous modifications and variations can be made in accordance with the concepts of the invention by one of ordinary skill in the art without undue burden. Therefore, all technical solutions which can be obtained by logic analysis, reasoning or limited experiments based on the prior art by the person skilled in the art according to the inventive concept shall be within the scope of protection defined by the claims.

Claims (14)

1. A laser etching system for electrode layer patterning capable of patterning a conductive layer on a first surface of a substrate of a touch panel of a double-sided structure with a laser beam without damaging the conductive layer on a second surface of the substrate, comprising;

a laser for generating and emitting the laser beam; the laser etching platform is used for bearing and fixing the substrate of the touch panel, so that the first surface faces the laser beam, and the second surface is attached to the laser etching platform;

wherein the laser etching system further comprises an optical element such that a ratio of a spot area of the laser beam irradiated at the second surface to a spot area irradiated at the first surface is not less than 1.2.

2. The laser etching system of claim 1, wherein the laser beam is a plurality of laser beams, the spots of the plurality of laser beams impinging at the first surface coincide, and the spots of the laser beam impinging at the second surface are separated from each other.

3. The laser etching system of claim 2, wherein at least one of the laser beams is incident on the first surface at an angle of less than 90 ° relative to the first surface.

4. The laser etching system of claim 1, wherein the optical element forms the laser beam passing therethrough into a positive defocus laser beam focused outside the substrate, the positive defocus laser beam having a larger spot area at the second surface than at the first surface.

5. The laser etching system of claim 4, wherein the angle at which the positive defocus laser beam is incident on the first surface is less than 90 degrees relative to the first surface.

6. The laser etching system of claim 4, wherein the laser beam is a plurality of laser beams, the spots of the plurality of laser beams impinging at the first surface coincide, and the spots of the laser beam impinging at the second surface are separated from each other.

7. The laser etching system of claim 6, wherein at least one of the laser beams is incident on the first surface at an angle of less than 90 ° relative to the first surface.

8. The laser etching system of claim 2 or 6, wherein the laser etching system has a plurality of lasers to which the plurality of laser beams respectively arrive.

9. The laser etching system of claim 2 or 6, wherein at least two of the plurality of laser beams are beamformed from a laser beam from a laser via a beam splitter.

10. The laser etching system of any of claims 1-7, wherein the laser etching system further comprises a blowing device for providing a flow of cooling gas to the laser beam at a spot location of the first surface.

11. The laser etching system of claim 10, wherein the laser etching system further comprises a cooling device for providing a coolant flow to the laser beam at a spot location at the second surface, wherein the coolant flow has a temperature at least 14 ℃ lower than a temperature of the cooling gas flow.

12. The laser etching system of claim 11, wherein a surface of the laser etching stage that conforms to the second surface of the substrate is formed with at least one recess disposed adjacent to a spot location of the laser beam that impinges on the second surface, the coolant stream being introduced into the recess to provide cooling at the spot location of the laser beam that impinges on the second surface.

13. The laser etching system of claim 12, wherein the cooling device is a cooling circulation device connected to the recess via a coolant inlet conduit and a coolant return conduit, the coolant flow from the cooling device entering the recess through the coolant inlet conduit and then returning to the cooling device through the coolant return conduit.

14. A laser etching method for patterning an electrode layer, comprising: use of a laser etching system according to any of the preceding claims, the optical element being arranged such that the ratio of the spot area of the laser beam impinging at the second surface to the spot area impinging at the first surface is not less than 1.2, followed by patterning of the conductive layer on the first surface of the substrate with the laser beam.