PCB inner wall pattern manufacturing method and PCB

Abstract

The application discloses a PCB inner wall pattern manufacturing method and a PCB. The method comprises the following steps: providing a multilayer board and a light-transmitting component, the multilayer board has a hole groove, the hole groove is a cavity formed by a recess, a through hole or a blind hole of the multilayer board, the light-transmitting component is arranged in the hole groove and performs light irradiation with a specified shape on a specified inner wall of the hole groove; an exposure material is arranged on the specified inner wall of the hole groove; after the light-transmitting component is arranged in the hole groove, the specified inner wall of the hole groove is irradiated with the specified shape, the specified line pattern is formed by exposure of the exposure material of the specified inner wall of the hole groove; after the light-transmitting component is taken out, the unexposed exposure material is removed, and the PCB with the inner wall pattern is obtained; the manufacturing process of the specified line pattern of the specified inner wall of the application is realized by light irradiation projection, does not involve depth control drilling and depth control milling, does not need to consider the precision problem of the depth control drilling and the depth control milling, greatly reduces the manufacturing cost of the PCB, and the single exposure can simultaneously complete the line pattern manufacturing requirement of multiple inner walls in the same hole groove.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of PCB manufacturing, in particular to a PCB inner wall pattern manufacturing method and a PCB. BACKGROUND

[0002] The current mainstream PCB groove bottom and groove inner wall pattern manufacturing method mainly uses irregular convex drill or milling cutter for depth control drilling or depth control milling, and the shape of the manufactured circuit pattern can only be rectangular or square. The shape of the manufactured circuit pattern is too single, and cannot meet the manufacturing requirements of different circuit pattern shapes of the groove bottom and groove inner wall.

[0003] In addition, the above-mentioned PCB groove bottom and groove inner wall pattern manufacturing method has high requirements for the precision and position accuracy of depth control, greatly increasing the manufacturing cost. The size accuracy of the circuit pattern manufactured by the conventional depth control precision is poor, and it is difficult to meet the high-precision PCB manufacturing requirements. SUMMARY

[0004] The purpose of the present application is to provide a PCB inner wall pattern manufacturing method and a PCB. After a specially prepared light-transmitting component is placed in a hole groove, light with a specified shape is irradiated on the specified inner wall of the hole groove to expose the specified inner wall of the hole groove to form a specified circuit pattern. The manufacturing process of the specified circuit pattern of the specified inner wall is realized by light projection, without involving depth control drilling and depth control milling, without considering the precision of depth control drilling and depth control milling, greatly reducing the manufacturing cost of the PCB. Moreover, single exposure can simultaneously complete the circuit pattern manufacturing requirements of multiple inner walls in the same hole groove, with high manufacturing efficiency. In addition, the precision of the specified circuit pattern depends on the manufacturing precision of the light-transmitting component. By reasonably setting the structure of the light-transmitting component, the circuit pattern precision of the specified inner wall of the hole groove can be greatly improved to meet the higher-precision PCB manufacturing requirements.

[0005] In order to achieve the above-mentioned purpose, the present application discloses a PCB inner wall pattern manufacturing method, which comprises the following steps:

[0006] S1. Providing a multi-layer board and a light-transmitting component, the multi-layer board having a hole groove, the hole groove being a cavity formed by a groove, a through hole or a blind hole of the multi-layer board, and the light-transmitting component being capable of being placed in the hole groove and irradiating light with a specified shape on a specified inner wall of the hole groove;

[0007] S2. Providing an exposure material on the specified inner wall of the hole groove;

[0008] S3. After the light-transmitting component is placed in the hole groove, light with a specified shape is irradiated on the specified inner wall of the hole groove to expose the exposure material on the specified inner wall of the hole groove to form a specified circuit pattern;

[0009] S4, after the light-transmitting member is taken out, the unexposed exposure material is removed to obtain a PCB with an inner wall pattern.

[0010] Preferably, the light-transmitting member comprises a closed and hollow box, when the box is placed in the hole slot, the outer wall of the box is tightly matched with the inner wall of the hole slot, the box is provided with a light-transmitting gap with a specified shape corresponding to the specified inner wall part of the hole slot, the light-transmitting gap is a hollow structure or a transparent solid structure, and the box wall part other than the light-transmitting gap is in a light-blocking structure.

[0011] Specifically, the light-transmitting member further comprises a light emitter, and the light emitter is arranged on the inner wall of the top end of the box.

[0012] Specifically, the light-transmitting member further comprises a light emitter and a light guide, the light emitter is located outside the box, the top end of the box is provided with a avoiding hole, one end of the light guide extends into the box through the avoiding hole, and the other end of the light guide is connected to the light emitter.

[0013] Specifically, the light emitter is direct light.

[0014] Preferably, the light-transmitting member comprises a light emitter and a box with an open top end and hollow, the light emitter is located above the box, when the box is placed in the hole slot, the outer wall of the box is tightly matched with the inner wall of the hole slot, the box is provided with a light-transmitting gap with a specified shape corresponding to the specified inner wall part of the hole slot, the light-transmitting gap is a hollow structure or a transparent solid structure, and the box wall part other than the light-transmitting gap is in a light-blocking structure.

[0015] Specifically, the light type of the light emitter is diffuse light, direct light or shadowless light.

[0016] Preferably, the inner edge of the light-transmitting gap is wedge-shaped.

[0017] Preferably, if the light-transmitting gap is a hollow structure, and the pattern surrounded by the light-transmitting gap is a closed pattern, the box wall part inside the closed pattern is connected to the box wall part outside the closed pattern through a connecting piece.

[0018] Preferably, the inner wall or the outer wall of the box is coated with a reflective material.

[0019] Preferably, the light-transmitting member is provided with a first fixing piece, the inner wall of the hole slot is embedded with a second fixing piece corresponding to the first fixing piece, and the first fixing piece and the second fixing piece are attracted to each other to position the light-transmitting member in the hole slot.

[0020] Preferably, the height of the box is equal to the depth of the hole slot.

[0021] Preferably, the height of the box is greater than the depth of the hole slot, and the outer wall of the box is provided with a scale along the height.

[0022] Preferably, the step S2 specifically comprises:

[0023] copper plating is performed on the multilayer board;

[0024] a photosensitive film is coated on the designated inner wall of the hole slot, wherein the photosensitive film is a wet film or a photosensitive ink;

[0025] high-temperature heating treatment is performed on the photosensitive film to fix the photosensitive film on the designated inner wall of the hole slot.

[0026] Preferably, in the step S4, the unexposed exposure material is removed, specifically comprising:

[0027] the multilayer board is sequentially subjected to development and etching treatment;

[0028] the unexposed photosensitive film is removed by organic solution cleaning.

[0029] Preferably, the step S2 specifically comprises:

[0030] conductive glue is coated on the designated inner wall of the hole slot.

[0031] Preferably, in the step S4, the unexposed exposure material is removed, specifically comprising:

[0032] the designated inner wall is heated by a hot air blower;

[0033] the unexposed conductive glue is removed by organic solution cleaning.

[0034] Correspondingly, the application also discloses a PCB prepared by the PCB inner wall pattern making method.

[0035] Compared with the prior art, the application places a specially prepared light-transmitting member in the hole slot, and then performs light irradiation with a specified shape on the designated inner wall of the hole slot to expose the designated inner wall of the hole slot to form a designated line pattern. On the one hand, the making process of the designated line pattern of the designated inner wall is realized by light irradiation projection, without involving depth control drilling and depth control milling, and without considering the precision of the depth control drilling and the depth control milling, thereby greatly reducing the manufacturing cost of the PCB. On the other hand, the single exposure can simultaneously complete the line pattern making requirements of multiple inner walls in the same hole slot, and the manufacturing efficiency is high. On the other hand, the precision of the designated line pattern depends on the manufacturing precision of the light-transmitting member, and by reasonably setting the structure of the light-transmitting member, the line pattern precision of the designated inner wall of the hole slot can be greatly improved to meet the higher precision PCB manufacturing requirements. BRIEF DESCRIPTION OF DRAWINGS

[0036] Figure 1 is a flow chart of the PCB inner wall pattern making method of the present application;

[0037] Figure 2 is a structural schematic diagram of the multilayer board when the hole slot is a groove;

[0038] Figure 3 is a structural schematic diagram of the multilayer board when the hole slot is a blind hole;

[0039] Figure 4 is a structural schematic diagram of the multilayer board when the hole slot is a through hole;

[0040] Figure 5 is a structural schematic diagram of the box body in a rectangular shape when the box body is in a fully closed structure;

[0041] Figure 6 is a structural schematic diagram of the box body in a cylindrical shape when the box body is in a fully closed structure;

[0042] Figure 7 is a structural schematic diagram of the box body when a same box wall is mixed with a non-closed pattern surrounded by one light-transmitting gap and a closed pattern surrounded by another light-transmitting gap;

[0043] Figure 8 is a structural schematic diagram of the illuminator placed in the inner wall of the top end of the box body of the present application; Figure 5

[0044] Figure 9 is a structural schematic diagram of the illuminator suspended in the interior of the box body of the present application; Figure 5

[0045] Figure 10 is a structural schematic diagram of the box body in a rectangular shape when the box body is in a semi-closed structure with an open upper end;

[0046] Figure 11 is a structural schematic diagram of the illuminator placed above the box body of the present application; Figure 10

[0047] Figure 12 is a structural schematic diagram of the illuminator of the present application, wherein the light is guided into the box body through the light guide body;

[0048] is a structural schematic diagram of the box body and the light guide body in an integrally formed structure and both being light guide bodies;

[0049] Figure 13 is a structural schematic diagram of the inner opening edge of the light-transmitting gap in a wedge shape;

[0050] Figure 14 ​​​It is a light-transmitting gap fixed structure schematic diagram of the present application, wherein the light-transmitting gap is in a hollow structure and the pattern surrounded by the light-transmitting gap is a closed pattern;

[0051] Figure 15 It is a reflection schematic diagram of the box body inside the present application;

[0052] Figure 16 It is a structure schematic diagram of the present application, wherein the light-reflecting material is irregularly arranged in a non-planar manner;

[0053] Figure 17 It is a structure schematic diagram of the present application, wherein the light-transmitting member is flush with the multi-layer board, and is fixed by the first fixing member and the second fixing member;

[0054] Figure 18 It is a structure schematic diagram of the present application, wherein the light-transmitting member protrudes out of the multi-layer board, and is fixed by the first fixing member and the second fixing member. DETAILED DESCRIPTION

[0055] To make the technical content, structural features, achieved purposes and effects of the present application clear, the following will be described in detail in combination with the embodiments and the accompanying drawings.

[0056] Please refer to Figures 1-18 The PCB with inner wall pattern of the present embodiment is obtained by a PCB inner wall pattern manufacturing method, and the PCB inner wall pattern manufacturing method comprises the following steps:

[0057] S1, providing a multi-layer board 1 and a light-transmitting member, the multi-layer board 1 has a hole slot 2, the hole slot 2 is a cavity formed by a groove, a through hole or a blind hole of the multi-layer board 1, and the light-transmitting member can be placed in the hole slot 2 and irradiate the specified inner wall of the hole slot 2 with a specified shape, Figure 2 、 Figure 3 and Figure 4 respectively show the structure schematic diagram of the multi-layer board 1 when the hole slot 2 is a groove, a blind hole and a through hole.

[0058] The multi-layer board 1 is obtained by spacing and pressing the multi-layer core board and the multi-layer prepreg, which has a certain thickness, and at least one hole slot 2 with a certain depth can be formed on the multi-layer board 1 by drilling, slotting and other methods. Since the hole slot 2 has a certain depth, it is suitable to make a circuit pattern on the inner wall of the hole slot 2.

[0059] It can be understood that the present application focuses on the hole slot 2 Figure 2 The rectangular groove is shown in the figure, at this time, the box body 3 corresponds to Figure 5The box is shown as a fully closed hollow rectangular shape. Of course, the cavity shape of the hole groove 2 here includes but is not limited to traditional shapes such as rectangle, square, etc., but also can be cylindrical, polygonal, conical, arc-shaped, etc., and the shape of the light-transmitting member needs to be consistent with the shape of the cavity of the hole groove 2. Figure 6 The structure diagram when the box 3 is cylindrical is shown. The cavity shape of the hole groove 2 is not limited as long as the light-transmitting member can be normally placed in the hole groove 2.

[0060] The present application can satisfy the production of line patterns on the inner bottom wall and / or at least one inner side wall in the same hole groove 2. The line patterns on the inner bottom wall and / or at least one inner side wall in the hole groove 2 can be the same or different, that is, the present application can only produce line patterns on the inner bottom wall or at least one inner side wall of the hole groove 2, or can simultaneously produce line patterns on the inner bottom wall and at least one inner side wall in the hole groove 2.

[0061] S2, an exposure material is arranged on the specified inner wall of the hole groove 2.

[0062] S3, after the light-transmitting member is placed in the hole groove 2, light with a specified shape is irradiated on the specified inner wall of the hole groove 2 to expose the exposure material on the specified inner wall of the hole groove 2 to form a specified line pattern.

[0063] S4, after the light-transmitting member is taken out, the unexposed exposure material is removed to obtain a PCB with an inner wall pattern.

[0064] Preferably, the light-transmitting member includes, for example Figure 5 The box 3 shown is closed and hollow. When the box 3 is placed in the hole groove 2, each outer wall of the box 3 tightly matches each inner wall of the hole groove 2. The box 3 is provided with a light-transmitting gap 4 with a specified shape corresponding to the specified inner wall part of the hole groove 2. The light-transmitting gap 4 is a hollow structure or a transparent solid structure. The box wall of the box 3 is in a light-blocking structure except the light-transmitting gap 4.

[0065] It can be understood that, in order to avoid the size of the light with a specified shape projected on the specified inner wall of the hole groove 2 being inconsistent with the size of the light-transmitting gap 4, the present embodiment needs to make the shape of the box 3 consistent with the shape of the cavity of the hole groove 2, and make each outer wall of the box 3 placed in the hole groove 2 tightly match the corresponding inner wall of the hole groove 2. At this time, each outer wall of the box 3 tightly matches each inner wall of the hole groove 2, that is, there is no gap between the box 3 and the hole groove 2, which avoids the inconsistency between the specified line pattern obtained by exposure and the actual required specified line pattern due to imaging magnification when the light is projected because of the gap between the box 3 and the hole groove 2.

[0066] Of course, in other preferred modes, the outward walls of the box 3 and the inward walls of the hole groove 2 can have a certain gap, in which case, the equal scaling relationship between the light-transmitting slit 4 and the designated circuit pattern needs to be reasonably calculated in combination with the imaging principle and the gap size to reasonably make the size of the light-transmitting slit 4, which will not be described here.

[0067] The same box wall here can be provided with various types of light-transmitting slits 4, Figure 5 The light-transmitting slit 4 shown is a simple non-closed pattern, Figure 7 A combination of a light-transmitting slit 4 with a non-closed pattern and another light-transmitting slit 4 with a closed pattern is shown.

[0068] Specifically, the light-transmitting member further comprises a light emitter 5, which is Figure 8 The light emitter 5 shown is provided on the inner wall of the top end of the box 3, which can be self-powered and connected to an external power source through a line provided on the box 3. In this case, the light-transmitting member is built-in with the light emitter 5, and the light emitted by the light emitter 5 passes through the light-transmitting slit 4 to irradiate the designated inner wall of the hole groove 2 at a one-to-one ratio. The type of light emitted by the light emitter 5 here can be diffuse light, direct light or shadowless light, which maximizes or avoids the influence of light shadows in the box 3 and ensures that the type of light emitted by the light emitter 5 is not limited in the case of effective light emission along the light-transmitting slit 4. Of course, the light emitter 5 can also be Figure 9 The light emitter 5 is suspended inside the box 3 by a small fixing member such as a steel wire, and the specific position and fixing method of the light emitter 5 in the box 3 are not limited here.

[0069] In another preferred mode, the light emitter 5 is Figure 12 The light emitter 5 is shown as an external setting, specifically, the light-transmitting member further comprises a light emitter 5 and a light guide 6, the light emitter 5 is located outside the box 3, an avoiding hole is provided at the top end of the box 3, one end of the light guide 6 extends into the box 3 through the avoiding hole, and the other end is connected to the light emitter 5. Preferably, the light guide 6 here is an optical fiber, such as a plastic optical fiber. This preferred mode takes advantage of the stable light guiding characteristics of optical fiber to introduce external light into the box 3. The type of light emitted by the light emitter 5 here is direct light, which is introduced into the box 3 through the optical fiber, and then reflected, scattered and / or diffusely reflected in the box 3 to achieve full-angle light coverage of the inner cavity of the box 3, which maximizes or avoids the influence of light shadows in the box 3. Of course, in other preferred modes, the light guide 6 can also be a glass column or other light guide medium that can perform total reflection light guiding, and the specific material of the light guide 6 is not limited here.

[0070] For the box 3 asFigure 10 In the case of the upper end opening and hollow shape shown, the application further provides another preferred mode. Specifically, the light-transmitting member comprises a box body 3 and a light emitter 5, the box body 3 is arranged in an upper end opening and hollow shape, and the light emitter 5 is arranged in the box body 3 as Figure 11 The box body 3 is arranged above the hole groove 2, and when the box body 3 is arranged in the hole groove 2, the outer walls of the box body 3 tightly fit the inner walls of the hole groove 2. The box body 3 is provided with light-transmitting slits 4 with a specified shape corresponding to the specified inner wall part of the hole groove 2. The light-transmitting slits 4 are hollow structures or transparent solid structures. The walls of the box body 3 are light-shielding structures except for the light-transmitting slits 4. The light emitted by the light emitter 5 can be diffuse light, direct light or shadowless light. The light-transmitting slits 4 are not limited in type as long as the light shadow in the box body 3 is minimized or avoided and the light can effectively emit along the light-transmitting slits 4.

[0071] Preferably, the inner edge of the light-transmitting slit 4 is arranged in a wedge shape as Figure 13 The light emitted by the light-transmitting slit 4 can be reflected back into the box body 3 at a certain angle to enhance the uniformity of the light in the box body 3 and avoid insufficient light intensity emitted from the light-transmitting slit 4 due to excessive depth of the light-transmitting slit 4.

[0072] Preferably, if the light-transmitting slit 4 is a hollow structure and the figure surrounded by the light-transmitting slit 4 is a closed figure shown by the dashed line, the wall of the box body 3 located inside the closed figure is separated from the wall located outside the closed figure. In order to fix the wall of the box body 3 located inside the closed figure and the wall located outside the closed figure, a connecting piece 7 is arranged between the wall of the box body 3 located inside the closed figure and the wall located outside the closed figure. The connecting piece 7 can be a metal piece or a piece made of the same material as the wall of the box body 3. In this case, the connecting piece 7 can be made at the same time as the light-transmitting slit 4 is engraved or etched, which will not be described here. Figure 7 Figure 14 Preferably, in order to further improve the consistency of the light intensity in the box body 3, the inner wall or the outer wall of the box body 3 is coated with a reflective material 10 to improve the consistency of the light intensity in the box body 3 as

[0073] Preferably, in order to further improve the consistency of the light intensity in the box body 3, the inner wall or the outer wall of the box body 3 is coated with a reflective material 10 to improve the consistency of the light intensity in the box body 3 as Figure 15 In actual use, in order to avoid scratching the reflective material 10 arranged on the inner wall or the outer wall of the box body 3, the reflective material 10 is usually directly coated on the inner wall of the box body 3. Further, the reflective material is arranged in a wedge shape as Figure 16 ​The irregular, non-planar arrangement shown, such as the reflective material being set as a randomly formed rough surface, means that the reflective material in different parts has different reflection angles, thereby achieving diffuse reflection inside the box 3, which further improves the consistency of light intensity in various parts inside the box 3 through diffuse reflection.

[0074] Preferably, in order to better position the housing 3 within the slot 2, the light-transmitting component is as follows: Figure 17 The diagram shows a first fixing member 8, and a second fixing member 9 embedded in the inner wall of the slot 2 corresponding to the first fixing member 8. The first fixing member 8 and the second fixing member 9 attract each other to position the light-transmitting component within the slot 2. It is understood that in this embodiment, both the first fixing member 8 and the second fixing member 9 are magnets, and their magnetic properties are opposite to each other. Of course, in other preferred embodiments, one of the first fixing member 8 and the second fixing member 9 is a magnet, and the other is a metal part that can be attracted by a magnet. Furthermore, it is worth noting that the second fixing member 9 needs to be embedded in a location within the inner wall of the slot 2 where no circuit pattern is required, and the second fixing member 9 must not contact the circuit pattern or other metal bodies that come into contact with the circuit pattern to avoid magnetic interference or leakage.

[0075] Preferably, in order to better improve the placement accuracy of the box 3, the height of the box 3 is as follows: Figure 17 The depth shown is equal to that of the slot 2, so that when the housing 3 is placed in the slot 2, and the end face of the housing 3 is flush with the surface of the multilayer board 1, the placement of the housing 3 can be visually confirmed, avoiding exposure deviations caused by improper placement of the housing 3. In other preferred embodiments, the height of the light-transmitting member is as follows: Figure 18 The depth shown is greater than that of the slot 2. The outer wall of the light-transmitting component is provided with a scale set along the height so that the operator can directly confirm the placement of the box 3 by visual inspection according to the scale value, so as to avoid exposure deviation caused by the box 3 not being placed in place.

[0076] Preferably, step S2 specifically includes:

[0077] The multilayer board 1 is copper plated;

[0078] A photosensitive film is coated on a designated inner wall of the groove 2, wherein the photosensitive film is a wet film or a photosensitive ink;

[0079] The photosensitive film is subjected to high-temperature heating treatment to fix the photosensitive film to the designated inner wall of the groove 2.

[0080] Preferably, in step S4, removing unexposed exposure material specifically includes:

[0081] The multi-layer board 1 is subjected to developing and etching in sequence.

[0082] The unexposed photosensitive film is removed by organic solution cleaning.

[0083] Preferably, the step S2 specifically comprises:

[0084] The specified inner wall of the hole groove 2 is coated with conductive glue.

[0085] Preferably, in the step S4, the unexposed exposure material is removed, specifically comprising:

[0086] The specified inner wall is heated by a hot air blower.

[0087] The unexposed conductive glue is removed by organic solution cleaning.

[0088] In combination Figures 1-18 , the application places a specially-made light-transmitting component in the hole groove 2, and then performs light irradiation with a specified shape on the specified inner wall of the hole groove 2 to expose the specified inner wall of the hole groove 2 to form a specified line pattern. On the one hand, the manufacturing process of the specified line pattern of the specified inner wall is realized by light projection, without involving depth-controlled drilling and depth-controlled milling, and without considering the precision of the depth-controlled drilling and depth-controlled milling, thus greatly reducing the manufacturing cost of the PCB. On the other hand, the single exposure can simultaneously complete the line pattern manufacturing requirements of multiple inner walls in the same hole groove 2, with high manufacturing efficiency. On the other hand, the precision of the specified line pattern depends on the manufacturing precision of the light-transmitting component, and by reasonably setting the structure of the light-transmitting component, the line pattern precision of the specified inner wall of the hole groove 2 can be greatly improved to meet the higher-precision PCB manufacturing requirements.

[0089] The above only describes the preferred embodiments of the application, and of course cannot limit the scope of the application. Any equivalent changes made within the scope of the patent application of the application are still within the scope of the application.

Claims

1. A method for making a pattern on an inner wall of a PCB, characterized in that, The method comprises the following steps: providing a multi-layer board and a light-transmitting component, the multi-layer board having a hole slot, the hole slot being a cavity formed by a recess, a through hole or a blind hole of the multi-layer board, the light-transmitting component being capable of being placed in the hole slot and capable of illuminating a designated inner wall of the hole slot with a designated shape; providing an exposure material on the designated inner wall of the hole slot; after the light-transmitting component is placed in the hole slot, illuminating the designated inner wall of the hole slot with a designated shape to expose the exposure material on the designated inner wall of the hole slot to form a designated line pattern; after the light-transmitting component is removed, removing the unexposed exposure material to obtain a PCB with an inner wall pattern; the light-transmitting component comprises a light emitter and a closed and hollow box, when the box is placed in the hole slot, each outer wall of the box is tightly matched with each inner wall of the hole slot, the box is provided with a light-transmitting gap with a designated shape corresponding to the designated inner wall of the hole slot, the light-transmitting gap is a hollow structure or a transparent solid structure, the box wall of the box is a light-blocking structure except the light-transmitting gap, and the light emitter is arranged on the inner wall of the top end of the box; the inner wall or the outer wall of the box is coated with a light-reflecting material, the light-reflecting material is arranged in an irregular non-planar manner, and the light-reflecting material is arranged in a randomly formed rough surface; the light-transmitting component is provided with a first fixing member, the inner wall of the hole slot is embedded with a second fixing member corresponding to the first fixing member, and the first fixing member and the second fixing member are attracted to each other to position the light-transmitting component in the hole slot.

2. The method of claim 1, wherein the inner wall of the PCB is formed by a process selected from the group consisting of: etching, laser ablation, and mechanical milling. The light emitter is a diffuse light, a direct light or a shadowless light.

3. The method for fabricating the PCB inner wall pattern as described in claim 1, characterized in that, The inner edge of the light-transmitting gap is arranged in a wedge shape.

4. The method for fabricating the PCB inner wall pattern as described in claim 1, characterized in that, If the light-transmitting gap is a hollow structure and the pattern surrounded by the light-transmitting gap is a closed pattern, the box wall of the box located in the closed pattern is connected to the box wall of the box located outside the closed pattern through a connecting member.

5. The method for fabricating the PCB inner wall pattern as described in claim 1, characterized in that, The height of the box is equal to the depth of the hole slot.

6. The method for fabricating the PCB inner wall pattern as described in claim 1, characterized in that, The height of the box is greater than the depth of the hole slot, and the outer wall of the box is provided with a scale arranged along the height.

7. The method for fabricating the PCB inner wall pattern as described in claim 1, characterized in that, The exposure material is arranged on the designated inner wall of the hole slot, specifically including: copper plating is performed on the multi-layer board; a photosensitive film is coated on the designated inner wall of the hole slot, wherein the photosensitive film is a wet film or a photosensitive ink; high-temperature heating treatment is performed on the photosensitive film to fix the photosensitive film on the designated inner wall of the hole slot.

8. The method for fabricating the PCB inner wall pattern as described in claim 7, characterized in that, The unexposed exposure material is removed, specifically including: the multi-layer board is sequentially developed and etched; the unexposed photosensitive film is removed through organic solution cleaning.

9. The method for fabricating the PCB inner wall pattern as described in claim 1, characterized in that, The exposure material is arranged on the designated inner wall of the hole slot, specifically including: conductive glue is coated on the designated inner wall of the hole slot.

10. The method for fabricating the PCB inner wall pattern as described in claim 9, characterized in that, The unexposed exposure material is removed, specifically including: the designated inner wall is heated by a hot air blower; the unexposed conductive glue is removed through organic solution cleaning.

11. A PCB, characterized by The PCB inner wall pattern is obtained by the method according to any one of claims 1-10.

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