Smart card

Abstract

The utility model discloses a smart card. The intelligent card comprises a card body, the card body comprises a first printing substrate layer and a middle layer arranged on one side of the first printing substrate layer, the first printing substrate layer comprises a first slot, the middle layer comprises a chip assembly, a load element electrically connected with the chip assembly and a first bonding pad part electrically connected with the chip assembly, and the chip assembly comprises an information interaction chip; at least part of the contact disc is arranged in the first open groove, the contact disc comprises a functional layer and a connecting layer which are electrically connected, the connecting layer comprises a second bonding pad part, and the second bonding pad part and the first bonding pad part are correspondingly welded; and the fixing glue is arranged between the touch disc and the first printing substrate layer along the thickness direction of the intelligent card. According to the embodiment, the first bonding pad part and the second bonding pad part are connected in a welding manner, and the stability of connection between the touch disc and the card body is further improved through the fixing glue, so that the intelligent card can pass a bending and twisting test, and the use performance of the intelligent card is improved.

Description

Technical Field

[0001] This application relates to the field of smart card technology, and more particularly to a smart card. Background Technology

[0002] Smart cards typically refer to cards with an embedded chip module. Smart cards include standard cards, all with specific dimensions and made of plastic. They are media used to identify individuals and store their information. Various smart cards, such as work permits, ID cards, various financial transaction cards, and membership cards, are widely used in people's lives.

[0003] Due to limitations in the structural materials of existing smart cards, their performance cannot meet the requirements. Utility Model Content

[0004] This application provides a smart card in which the first and second pads are connected by welding, and the stability of the connection between the contact pad and the card body is further improved by fixing adhesive, so that the smart card can pass the bending and torsion test and improve the performance of the smart card.

[0005] This application provides a smart card, comprising: a card body, including a first printed substrate layer and an intermediate layer disposed on one side of the first printed substrate layer, the first printed substrate layer including a first slot, the intermediate layer including a chip assembly, a load element electrically connected to the chip assembly, and a first pad portion electrically connected to the chip assembly, the chip assembly including an information interaction chip; a contact pad, at least partially disposed within the first slot, the contact pad including an electrically connected functional layer and a connection layer, the connection layer including a second pad portion, the second pad portion and the first pad portion being correspondingly soldered; and a fixing adhesive, disposed between the contact pad and the first printed substrate layer along the thickness direction of the smart card.

[0006] According to the embodiments provided in this application, the contact pad further includes an insulating layer disposed between the functional layer and the connection layer, the functional layer including at least two functional areas; the second pad portion is electrically connected to different functional areas respectively through vias formed in the insulating layer.

[0007] According to the embodiments provided in this application, the insulating layer includes a central region, the via is at least partially located in the central region, and the orthographic projection of the second pad portion in the insulating layer is located within the central region.

[0008] According to the embodiments provided in this application, the extension trajectory of the via is set as a straight line or a curve.

[0009] According to the embodiments provided in this application, the insulating layer includes a central region and an edge region surrounding the central region. A via is provided in the central region, and a conductive material connection functional area and a second pad portion are provided in the via. The ratio of the area of ​​the central region to the sum of the areas of the central region and the edge region is less than or equal to one-half.

[0010] According to the embodiments provided in this application, the fixing adhesive includes a conductive adhesive, and the conductive adhesive is at least disposed on the surface of the insulating layer in the edge region facing away from the functional layer.

[0011] According to the embodiments provided in this application, the surface of the second pad portion facing away from the functional layer is coated with solder.

[0012] According to the embodiments provided in this application, the fixing adhesive includes a hot melt adhesive, which is disposed between the insulating layer and the first printed substrate layer.

[0013] According to the embodiments provided in this application, the hot melt adhesive is disposed on the periphery of the first pad portion and the second pad portion, and is bonded to the first printed substrate layer.

[0014] According to the embodiments provided in this application, the intermediate layer further includes a circuit board and a control element. The circuit board includes a power supply coil, which is electrically connected to the chip assembly. The control element is electrically connected to the load element and the chip assembly, respectively.

[0015] According to the embodiments provided in this application, the load element includes at least one of a light-emitting element and a fingerprint sensor.

[0016] According to the embodiments provided in this application, the first slot includes a first sub-slot and a second sub-slot that are connected to each other. The first sub-slot is disposed on the side of the second sub-slot away from the intermediate layer. The functional layer is at least partially disposed in the first sub-slot, the second pad is disposed in the second sub-slot, and the projected area of ​​the first sub-slot on the touch pad is greater than the projected area of ​​the second sub-slot on the touch pad.

[0017] According to the embodiments provided in this application, along the thickness direction of the smart card, the card body includes a first protective layer, a first printed substrate layer, an intermediate layer, a second printed substrate layer, and a second protective layer stacked together; the first slot is formed in the first protective layer and the first printed substrate layer.

[0018] The smart card provided in this embodiment includes a card body, a contact pad, and a fixing adhesive. The middle layer of the card body includes a chip assembly, a load element electrically connected to the chip assembly, and a first pad portion electrically connected to the chip assembly. The chip assembly and the load element are electrically connected so that the load element can perform corresponding actions according to the status of the chip assembly. The chip assembly includes an information interaction chip, which can be electrically connected to the contact pad through the first pad portion. This allows the functional layer of the contact pad to realize information interaction with the outside world, enabling functions such as payment transactions, access cards, and transportation cards. In this embodiment, the first pad portion and the second pad portion are connected by welding, and the fixing adhesive further improves the stability of the connection between the contact pad and the card body. While achieving electrical connection, it also achieves a fixed connection between the contact pad and the card body. Compared with the existing technology using ACF (Anisotropic Conductive Film) adhesive, the connection between the contact pad and the card body is more stable, allowing the smart card to pass bending and torsion tests and improving its performance. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments of this application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of a smart card according to an embodiment of this application;

[0021] Figure 2 This is an embodiment of the present application. Figure 1 Schematic diagram of the cross section at point AA;

[0022] Figure 3 This is a schematic diagram showing the relative positions of the card body and the touchpad according to an embodiment of this application;

[0023] Figure 4 This is a cross-sectional schematic diagram of a contact plate according to an embodiment of this application;

[0024] Figure 5 This is a cross-sectional schematic diagram of the contact plate according to another embodiment of this application;

[0025] Figure 6 This is a top view schematic diagram of a touch panel according to an embodiment of this application;

[0026] Figure 7 This is a top view of an intermediate layer according to an embodiment of this application;

[0027] Figure 8 This is another embodiment of the present application. Figure 1 Schematic diagram of the cross section at point AA;

[0028] Figure 9 This is a schematic diagram of a smart card according to another embodiment of this application.

[0029] Figure label:

[0030] 1. Card body; 11. First printed substrate layer; 12. Intermediate layer; 121. Chip assembly; 122. Power supply coil; 123. Load element; 124. First solder pad; 13. First protective layer; 14. Second printed substrate layer; 15. Second protective layer; 2. Contact pad; 21. Functional layer; 22. Connecting layer; 221. Second solder pad; 23. Insulating layer; 3. Fixing adhesive; K1. First slot; K11. First sub-slot; K12. Second sub-slot; K2. Via; ZA. Center area; BA. Edge area; GA. Functional area. Detailed Implementation

[0031] The features and exemplary embodiments of various aspects of this application will now be described in detail. In the following detailed description, numerous specific details are set forth in order to provide a comprehensive understanding of this application. However, it will be apparent to those skilled in the art that this application can be implemented without some of these specific details. The following description of embodiments is merely intended to provide a better understanding of this application by illustrating examples thereof.

[0032] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The embodiments will now be described in detail with reference to the accompanying drawings.

[0033] Relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another; they do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion; such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus that includes said element.

[0034] It should be understood that when describing the structure of a component, when referring to a layer or region as being "above" or "on top of" another layer or region, it can mean that it is directly above another layer or region, or that it contains other layers or regions between it and another layer or region. Furthermore, if the component is flipped over, that layer or region will be located "below" or "under" another layer or region.

[0035] Additionally, the term "and / or" in this article is merely a description of the relationship between related objects; it indicates that three relationships can exist. For example, A and / or B can represent: A existing alone; A and B existing simultaneously; and B existing alone. Furthermore, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0036] It should be understood that in the embodiments of this application, "B corresponding to A" means that B is associated with A; B can be determined based on A. However, it should also be understood that determining B based on A does not mean determining B solely based on A; B can also be determined based on A and / or other information.

[0037] Please see Figure 1 and Figure 3 , Figure 1 This is a schematic diagram of a smart card according to an embodiment of this application; Figure 2 This is an embodiment of the present application. Figure 1 Schematic diagram of the cross section at point AA; Figure 3 This is a schematic diagram showing the relative positions of the card body and the touchpad according to an embodiment of this application.

[0038] This application provides a smart card, including: a card body 1, including a first printed substrate layer 11 and an intermediate layer 12 disposed on one side of the first printed substrate layer 11, the first printed substrate layer 11 including a first slot K1, the intermediate layer 12 including a chip assembly 121, a load element 123 electrically connected to the chip assembly 121, and a first pad portion 124 electrically connected to the chip assembly 121, the chip assembly 121 including an information interaction chip; a touch pad 2, at least partially disposed in the first slot K1, the touch pad 2 including an electrically connected functional layer 21 and a connection layer 22, the connection layer 22 including a second pad portion 221, and the second pad portion 221 and the first pad portion 124 being correspondingly soldered; and a fixing adhesive 3, disposed between the touch pad 2 and the first printed substrate layer 11 along the thickness direction of the smart card.

[0039] The smart card provided in this embodiment of the utility model includes a card body 1, a contact pad 2, and a fixing adhesive 3. The intermediate layer 12 in the card body 1 includes a chip assembly 121, a load element 123 electrically connected to the chip assembly 121, and a first pad portion 124 electrically connected to the chip assembly 121. The chip assembly 121 and the load element 123 are electrically connected so that the load element 123 can perform corresponding actions according to the situation of the chip assembly 121. The chip assembly 121 includes an information interaction chip. The information interaction chip can be electrically connected to the contact pad 2 through the first pad portion 124, thereby realizing information interaction with the outside world through the functional layer 21 of the contact pad 2, and realizing functions such as payment transactions, access cards, and transportation cards.

[0040] Meanwhile, in this embodiment, the first solder pad 124 and the second solder pad 221 are connected by welding, and the stability of the connection between the contact pad 2 and the card body 1 is further improved by fixing adhesive 3. While realizing electrical connection, the fixed connection between the contact pad 2 and the card body 1 is also realized. Compared with the ACF adhesive (Anisotropic Conductive Film) bonding method in the prior art, the connection between the contact pad 2 and the card body 1 is more stable, which enables the smart card to pass the bending and torsion test and improves the performance of the smart card.

[0041] In this embodiment, the chip assembly 121 may include only the information interaction chip, that is, the information interaction chip located on the touch pad 2 in the prior art is moved to the middle layer 12. Alternatively, the chip assembly 121 may also include a load chip for controlling the specific operation of the load element 123.

[0042] It should be noted that the fixing adhesive 3 can be a hot melt adhesive, which is a 100% solid, fusible polymer that does not require solvents and contains no water. It is solid at room temperature and melts into a flowable liquid with a certain viscosity when heated to a certain temperature. The heat generated during the welding of the first solder pad 124 and the second solder pad 221 melts the hot melt adhesive. After welding is completed, the hot melt adhesive becomes solid, effectively improving the stability of the connection between the contact pad 2 and the card body 1.

[0043] Please see Figure 6 It should be noted that the functional layer 21 of the contact plate 2 is usually divided into multiple functional areas GA. For example, these functional areas GA are, in order, the input / output functional area, the clock functional area, the power supply functional area, the ground functional area, the reset functional area, and the idle functional area.

[0044] The first pad portion 124 and the second pad portion 221 can be soldered together using low-temperature solder.

[0045] Optionally, the surface of the second pad portion 221 facing away from the functional layer 21 is coated with solder. The first pad portion 124 on the card body may also be provided with solder, and the solder has a certain thickness so that solder remains on the pad after milling the groove K1.

[0046] A first slot K1 can be formed on the surface of the card body 1 by milling or other means. The first slot K1 can accommodate the fixed contact plate 2 on the one hand, and expose the first pad portion 124 of the intermediate layer 12 on the other hand, so that the second pad portion 221 of the contact plate 2 can be soldered to the first pad portion 124.

[0047] Please see Figures 4 to 6 In some optional embodiments, the contact pad 2 further includes an insulating layer 23 disposed between the functional layer 21 and the connection layer 22. The functional layer 21 includes at least two functional areas GA. The second pad portion 221 is electrically connected to different functional areas GA through vias K2 formed in the insulating layer 23.

[0048] In this embodiment, both the functional layer 21 and the connection layer 22 can be made of conductive materials, such as metal. An insulating layer 23 is provided on the functional layer 21 and the connection layer 22 so that different functional areas GA can be electrically connected through vias K2 and different second pad portions 221 to avoid mutual interference.

[0049] Please see Figure 4 The via K2 can be a through-hole structure, that is, the via K2 directly penetrates the upper and lower surfaces of the insulating layer 23. The functional layer 21 and the connecting layer 22 are connected by conductive material located in the via K2, which can be a lead wire, etc.

[0050] Please see Figure 5 The via K2 can also be extended inside the insulating layer 23 material to adjust the inlet and outlet positions of the via K2 on the upper and lower surfaces of the insulating layer 23, so as to facilitate the electrical connection between the functional area GA and the second pad portion 221 at different positions.

[0051] Optionally, the extension trajectory of via K2 can be set as a straight line or a curve. That is, the extension trajectory of via K2 can be a straight line, a broken line, or a curve. The specific selection depends on the functional area GA and the corresponding second pad 221 position, and there are no special limitations.

[0052] Please see Figure 6 In some alternative embodiments, the insulating layer 23 includes a central region ZA, the via K2 is at least partially located in the central region ZA, and the second pad portion 221 is projected onto the insulating layer 23 within the central region ZA.

[0053] It should be noted that in the prior art, the part of the functional layer 21 corresponding to the central area ZA is used to set the information interaction chip. However, in this embodiment, since the information interaction chip is set in the intermediate layer 12, the central area ZA can be used to set via K2 to connect with each functional area GA, thereby improving space utilization and facilitating the connection between the second pad part 221 and each functional area GA of the functional layer 21.

[0054] The second pad portion 221 is projected onto the functional layer 21 within the central region ZA, meaning the second pad portion 221 is located below the central region ZA, so that the second pad portion 221 can be connected to the functional region GA through the via K2.

[0055] In this embodiment, the area of ​​the central region ZA can be minimized to increase the coating area, i.e. the coating area of ​​the fixing adhesive 3, thereby increasing the stability of the connection between the touch screen 2 and the card body 1.

[0056] Optionally, the insulating layer 23 includes a central region ZA and an edge region BA surrounding the central region ZA. A via is provided in the central region ZA, and a conductive material connection functional area GA and a second pad portion 221 are disposed within the via. The ratio of the area of ​​the central region ZA to the sum of the areas of the central region ZA and the edge region BA is less than or equal to one-half. This reduces the size of the central region ZA, thereby increasing the area of ​​the conductive adhesive in the edge region BA and improving the stability of the connection between the intermediate layer 12 and the contact pad 2.

[0057] Optionally, the ratio of the area of ​​the central region ZA to the sum of the areas of the central region ZA and the edge region BA can be less than or equal to one-ninth, so as to further reduce the area of ​​the central region ZA and increase the coating area of ​​the conductive adhesive in the edge region BA.

[0058] Please see Figure 9 Optionally, the fixing adhesive 3 includes conductive adhesive, which is provided at least on the surface of the insulating layer 23 in the edge region BA on the side opposite to the functional layer 21.

[0059] In some optional embodiments, conductive adhesive covers the surface of the insulating layer 23 facing away from the functional layer 21 and fills the vias. In this embodiment, conductive adhesive can be simultaneously applied to the central area ZA and the edge area BA to further increase the application area of ​​the conductive adhesive and improve the stability of the connection between the card body 1 and the contact plate 2.

[0060] The conductive adhesive can specifically be ACF adhesive (Anisotropic Conductive Film).

[0061] Please see Figure 8 and Figure 9In some optional embodiments, the adhesive 3 is disposed on the periphery of the first pad portion 124 and the second pad portion 221 and is bonded to the first printed substrate layer 11.

[0062] It is understandable that the adhesive 3 can bond the first pad 124, the second pad 221 and the first printed substrate layer 11 respectively, effectively strengthening the connection between the first pad 124 and the second pad 221, avoiding problems such as desoldering of the first pad 124 and the second pad 221, and improving the stability of the connection between the contact pad 2 and the card body 1.

[0063] Please see Figure 7 In some optional embodiments, the intermediate layer 12 also includes a circuit board and control elements. The circuit board includes a power supply coil 122, which is electrically connected to the chip assembly 121. The control elements are electrically connected to the load element and the chip assembly, respectively.

[0064] Optionally, the magnetic field of the chip assembly 121 near the card reader requires that the induced current generated by the power supply coil 122 be able to power contactless communication. The larger the area around the power supply coil 122, the larger the induced current generated by the power supply coil 122.

[0065] Optionally, the power supply coil 122 is arranged in a ring, specifically in a square or circular arrangement.

[0066] Optionally, the circuit board can be a flexible circuit board.

[0067] Optionally, the control element can be a microcontroller unit (MCU), also known as a single-chip microcomputer or microcontroller. It is a chip-level computer that appropriately reduces the frequency and specifications of the central processing unit (CPU) and integrates peripheral interfaces such as memory, timer, USB, A / D conversion, UART, PLC, DMA, and even LCD driver circuits onto a single chip, forming a chip-level computer that can perform different combinations of control for different applications.

[0068] After receiving the signal from the chip assembly 121, the microcontroller unit can control the load element 123 to perform corresponding actions.

[0069] In some alternative embodiments, the load element 123 includes at least one of a light-emitting element and a fingerprint sensor.

[0070] The light-emitting element can be an LED (Light-Emitting Diode), and the microcontroller unit 121 can control the light-emitting element to display the light.

[0071] The chip component 121 can be electrically connected to the fingerprint sensor to enable fingerprint recognition.

[0072] Please see Figure 2 or Figure 6 In some optional embodiments, the first slot K1 includes a first sub-slot K11 and a second sub-slot K12 that are connected to each other. The first sub-slot K11 is disposed on the side of the second sub-slot K12 away from the intermediate layer 12. The functional layer 21 is at least partially disposed in the first sub-slot K11, and the second pad portion 221 is disposed in the second sub-slot K12. The projected area of ​​the first sub-slot K11 on the contact pad 2 is greater than the projected area of ​​the second sub-slot K12 on the contact pad 2.

[0073] It should be noted that the projected area of ​​the first sub-slot K11 on the contact plate 2 is larger than that of the second sub-slot K12 on the contact plate 2. That is, the size of the first sub-slot K11 is larger than the size of the second sub-slot K12, and the two form a stepped groove structure.

[0074] Please see Figure 8 In some optional embodiments, along the thickness direction of the smart card, the card body 1 includes a first protective layer 13, a first printed substrate layer 11, an intermediate layer 12, a second printed substrate layer 14, and a second protective layer 15 stacked together; a first slot K1 is formed in the first protective layer 13 and the first printed substrate layer 11.

[0075] It should be noted that the first slot K1 is formed between the first protective layer 13 and the first printed substrate layer 11, that is, the first protective layer 13 and the first printed substrate layer 11 are partially removed to form the first slot K1, exposing the first solder part at the corresponding position of the intermediate layer 12.

[0076] The first protective layer 13 is formed on the side of the first printed substrate layer 11 away from the intermediate layer 12 to protect the first printed substrate layer 11 and prevent damage to the pattern on the first printed substrate layer 11. Similarly, the second protective layer 15 is formed on the side of the second printed substrate layer 11 away from the intermediate layer 12 to protect the second printed substrate layer 11.

[0077] The first printing substrate layer 11 and the second printing substrate layer 14 can be printed with the required patterns according to actual needs. Of course, they can also be left unprinted without any special restrictions.

[0078] Optionally, the first protective layer 13, the first printed substrate layer 11, the intermediate layer 12, the second printed substrate layer 14, and the second protective layer 15 each include at least one of polyvinyl chloride (PVC), polyethylene terephthalate (PET), polycarbonate (PC), and polystyrene (PG).

[0079] The smart card provided in this application embodiment can be used to realize electronic transaction functions. A smart card is a type of card with a predetermined length, width, and thickness, and also features portability and ease of use. A smart card can be a debit card, credit card, stored-value card, public transport card, access card, or membership card, but is not limited to the card types listed above.

[0080] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and these modifications or substitutions should all be covered within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A smart card, characterized in that, include: The card body includes a first printed substrate layer and an intermediate layer disposed on one side of the first printed substrate layer. The first printed substrate layer includes a first slot. The intermediate layer includes a chip assembly, a load element electrically connected to the chip assembly, and a first pad portion electrically connected to the chip assembly. The chip assembly includes an information interaction chip. The contact pad is at least partially disposed within the first slot. The contact pad includes an electrically connected functional layer and a connection layer. The connection layer includes a second pad portion, and the second pad portion and the first pad portion are correspondingly soldered. The adhesive is disposed between the contact pad and the first printed substrate layer along the thickness direction of the smart card.

2. The smart card according to claim 1, characterized in that, The contact plate also includes an insulating layer disposed between the functional layer and the connecting layer, wherein the functional layer includes at least two functional areas; The second pad portion is electrically connected to different functional areas through vias formed in the insulating layer.

3. The smart card according to claim 2, characterized in that, The insulating layer includes a central region, the via is at least partially located in the central region, and the orthographic projection of the second pad portion in the insulating layer is located within the central region.

4. The smart card according to claim 2, characterized in that, The extension trajectory of the via is set in a straight line or a curve.

5. The smart card according to claim 2, characterized in that, The insulating layer includes a central region and an edge region surrounding the central region. A via is provided in the central region, and a conductive material connection functional area and a second pad portion are provided in the via. The ratio of the area of ​​the central region to the sum of the areas of the central region and the edge region is less than or equal to one-half.

6. The smart card according to claim 5, characterized in that, The fixing adhesive includes a conductive adhesive, which is provided at least on the surface of the insulating layer in the edge region facing away from the functional layer.

7. The smart card according to claim 2, characterized in that, The surface of the second pad, facing away from the functional layer, is coated with solder.

8. The smart card according to claim 2, characterized in that, The fixing adhesive includes a hot melt adhesive, which is disposed between the insulating layer and the first printed substrate layer.

9. The smart card according to claim 8, characterized in that, The hot melt adhesive is applied to the periphery of the first pad portion and the second pad portion, and is bonded to the first printed substrate layer.

10. The smart card according to claim 1, characterized in that, The intermediate layer also includes a circuit board and a control element. The circuit board includes a power supply coil, which is electrically connected to the chip assembly. The control element is electrically connected to the load element and the chip assembly, respectively.

11. The smart card according to claim 1, characterized in that, The load element includes at least one of a light-emitting element and a fingerprint sensor.

12. The smart card according to claim 1, characterized in that, The first slot includes a first sub-slot and a second sub-slot that are connected to each other, with the first sub-slot located on the side of the second sub-slot away from the intermediate layer; The functional layer is at least partially disposed in the first sub-slot, the second pad is disposed in the second sub-slot, and the projected area of ​​the first sub-slot on the touch pad is greater than the projected area of ​​the second sub-slot on the touch pad.

13. The smart card according to claim 1, characterized in that, Along the thickness direction of the smart card, the card body includes a first protective layer, a first printed substrate layer, an intermediate layer, a second printed substrate layer, and a second protective layer stacked together. The first slot is formed on the first protective layer and the first printed substrate layer.

Images