Patent Description:
Multiple assays are very important in immunological assays and molecular diagnostic assays. The multiple assay refers to simultaneous quantifying multiple analytes in a single assay. The multiple assay uses multiple capture agents, and each capture agent being specific with a target macromolecule. In a chip-based multiplex assay, each type of capture agent is attached to a predetermined location of the chip. The amounts of multiple targets in a complex sample are determined by detecting signals of the molecules at each location of the same type of capture agent. In suspension array multiplex assay, microbeads are suspended in the solution. These microbeads contain identification elements (such as "codes") that can be embedded, printed, or produced by one or more elements of the microbeads. Each type of capture agent is fixed to the microbeads with the same code, and the signals emitted from the detected molecules on the microbeads with the specific code reflect the amount of the corresponding targets.

The current codes of the microbead are produced by marking an opaque substance or fluorescent substance inside the microbead. The codes of the microbead can be identified by a distribution of the opaque substance or fluorescent substance. As shown in <FIG>, the black region represents the opaque substance or fluorescent substance. However, such coding method has following shortcomings. <NUM>) The production cost of the microbead is high, and additional processes and materials are needed to mark the codes. <NUM>) There are several subsequent identification steps, and the identification of such codes needs additional white light image or specific fluorescence image of the microbead. <NUM>) Forming the codes inside the microbead limits the number of codes and the size of the region for biological reaction.

There is another way in this field for coding microbead, by engraving codes of different depths, different shapes, and different intervals around the circular microbeads, thereby greatly increasing the number of coding combinations as shown in <FIG>. However, such coding method also has following shortcomings. <NUM>) The microbead is round, and fewer codes can be engraved on per unit region of the microbead. <NUM>) The positioning of the microbead is difficult. During image processing, it is difficult to positioning the microbead, and the positioning accuracy is low. <NUM>) There is a gap between the codes, which wastes space and reduces the length of the codes. <NUM>) The direction of the codes can only be obtained by the position of the mark. When the mark position is shielded, damaged, or the identification thereof is wrong, the direction of the codes may be unidentified or even wrongly identified. Conventional microbeads are known from D1 (<CIT>) and D2 (<CIT>).

Therefore, a microbead that can overcome at least one of the above shortcomings.

The present disclosure provides a microbead with a code engraved on outside of the microbead. The microbead includes a central region and an edge region surrounding the central region. An outer contour of the edge region before and after engraving the code is non-circular. The edge region includes a plurality of coding positions, the code of the microbead is engraved on the plurality of coding positions, and each bit of the code corresponds to each of the plurality of coding positions. The edge region includes corner regions and side regions, and the corner regions and the side regions are connected to each other in a direction surrounding the central region. The corner regions are provided with positioning devices and/or marking positions, and the positioning devices and/or the marking positions are configured to allow a computer identification device to identify a front side and a back side of the microbead, a starting position of the code, and a direction of the code.

In one embodiment, the microbead has a first length in a first dimensional direction and a second length in a second dimensional direction perpendicular to the first dimensional direction. The first length is longer than the second length, and the edge region surrounds the central region at least on a plane formed by the first dimensional direction and the second dimensional direction.

In one embodiment, the plurality of coding positions is at least arranged on the plane formed by the first dimensional direction and the second dimensional direction.

In one embodiment, a portion of the corner regions is processed to have a shape different from other portions of the corner regions, and the portion of the corner region as a whole serves as the positioning device.

In one embodiment, a portion of the corner regions defines a through hole penetrating the microbead, and the through hole serves as the positioning device. Or a portion of the corner regions is provided with a positioning protrusion, and the positioning protrusion serves as the positioning device.

In one embodiment, the marking position is an oblique line segment or an arc segment generated by cutting one of the corner regions.

In one embodiment, a center of a circle where the arc segment is located is on the microbead.

In one embodiment, the plurality of coding positions is disposed on the side regions. Or the plurality of coding positions is disposed on the side regions and the corner regions.

In one embodiment, the code is presented by engraving code patterns on the plurality of coding positions, and the code patterns is a combination of one or more patterns.

In one embodiment, the coding patterns are triangular coding patterns, rectangular coding patterns, trapezoidal coding patterns, or any combination thereof.

In one embodiment, the coding pattern of at least one of the plurality of coding positions is used to indicate a front side and a back side of the microbead and a direction of the code.

In one embodiment, the coding pattern of the at least one of the plurality of coding positions has a preset vertex, the preset vertex deviates to or from a preset direction, and the preset direction is the direction of the code on the microbead.

In one embodiment, at least one of the coding patterns has directionality, and the directionality of the coding pattern is used as a constituent factor of the code.

In one embodiment, the coding pattern having the directionality further has a preset vertex. The preset vertex deviates from or to one of at least two different preset directions, and the different preset directions which the preset vertex deviates from or to represent another different code.

In the microbead of the present disclosure, since the shape of the microbead deviates from circular, compared to the circular microbead, a ratio of the overall surface area of the non-circular microbead with respect to the perimeter of the microbead before coding is smaller, and more coding positions can be set on the same consumable region, or the size of the consumable region can be reduced by setting a same number of coding positions. Thus, the utilization rate of microbeads can be improved.

Implementations of the present technology will now be described, by way of embodiment, with reference to the attached figures. Obviously, the drawings are only some embodiments of the present disclosure. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative work.

Implementations of the disclosure will now be described, by way of embodiments only, with reference to the drawings. The described embodiments are only portions of the embodiments of the present disclosure, rather than all the embodiments. The disclosure is illustrative only, and changes may be made in the detail within the principles of the present disclosure. It will, therefore, be appreciated that the embodiments may be modified within the scope of the claims.

Referring to <FIG>, which are diagrammatic views of a microbead <NUM> before and after coding according to a first embodiment of the present disclosure. The microbead <NUM> is non-circular, which can be rectangular (including square, rectangular), trapezoidal, elliptical, and other regular or irregular shape. Specifically, in the embodiment, the microbead <NUM> is a rectangular microbead, and the code is engraved on the outside of the microbead <NUM>. Furthermore, the microbead <NUM> includes an edge region <NUM> and a central region <NUM> surrounded by the edge region <NUM>. The edge region <NUM> includes corner regions <NUM> and side regions <NUM> besides the corner region <NUM>. The corner regions <NUM> are where four corners of the rectangle are located. One corner region 13a includes a marking position A. The remaining three corner regions 13b are used as positioning devices for positioning. The marking position A and the three corner regions 13b for positioning enable a computer identification device <NUM> (shown in <FIG>) to accurately position the microbead <NUM>. The side regions <NUM> are where the long and short sides of the rectangle adjacent to the corner regions <NUM> are located. At least one coding position <NUM> is disposed on each side region <NUM>. Each coding position <NUM> is used to engrave a code pattern. In the embodiment, the marking portion A is an oblique line segment generated by cutting the corner region 13a. Lengths of the long and short sides after cutting the corner region <NUM> are different. In the embodiment shown in <FIG>, for a rectangular microbead <NUM> having a length of <NUM>, a width of <NUM>, and a consumable region of <NUM><NUM>, one corner region 13a of <NUM>*<NUM> is cut to form the marking position A. An included angle E is formed between the marking position A and a triangular coding pattern on the adjacent coding position <NUM>, which is approximately <NUM>°. Starting from the mark position A, two adjacent coding positions <NUM> are set on the first short side next to the mark position A in a clockwise direction. Four adjacent coding positions <NUM> are set on the first long side next to the first short side in the clockwise direction. Three coding positions <NUM> are set on the second short side next to the first long side in the clockwise direction. Three coding positions <NUM> are set on the second long side next to the second short side in the clockwise direction. Thus, a code with a length of <NUM>-bit can be set on the microbead <NUM>, and multiple coding positions on the same side are closely adjacent to each other. In the embodiment shown in <FIG>, starting from the marking position A, each coding position <NUM> is engraved with a coding pattern, and the coding pattern is a triangle with a vertex facing the inside of the microbead <NUM>. In other embodiments, the coding pattern may also be a triangle with the vertex facing the outside of the microbead <NUM>. By engraving the triangular coding patterns on different coding positions <NUM> to form different coding combinations, <NUM><NUM>=<NUM> different codes can be formed.

Referring to <FIG>, which are diagrammatic views of a microbead <NUM> before and after coding according to a second embodiment of the present disclosure. The microbead <NUM> in the embodiment is substantially the same as the microbead <NUM> in the first embodiment, except that the microbead <NUM> as a whole is more slender than the microbead <NUM>. Specifically, in the embodiment, the long side of the rectangular microbead <NUM> is <NUM>, the short side is <NUM>, and the consumable region is <NUM><NUM>. One corner region 23a of <NUM>*<NUM> is cut to form the marking position A. Starting from the marking position A, one coding position <NUM>, five coding positions <NUM>, two coding positions <NUM>, and four coding positions <NUM> are respectively set on the first short side next to the mark position A, the first long side next to the first short side, the second short side next to the first long side, and the second long side next to the second short side. Compared with microbead <NUM>, the microbead <NUM> has a larger aspect ratio (that is, the ratio of the long side to the wide side), and the code with a length of <NUM>-bit can still be set although the size of consumable region is reduced. <FIG> shows one code of the microbead <NUM>. It can be understood that by engraving the triangular code patterns on different code positions <NUM> to form different code combinations, <NUM><NUM>=<NUM> different codes can be formed.

Referring to <FIG>, which are diagrammatic views of a microbead <NUM> before and after coding according to a third embodiment of the present disclosure. The microbead <NUM> in the embodiment is substantially the same as the microbead <NUM> in the first embodiment, except that the marking position A is an arc segment generated by cutting one corner region 33a. A center of a circle where the arc segment is located is at the microbead <NUM>, and the circle has a radius of <NUM>. The arc segment and the triangular code pattern on the adjacent coding position <NUM> form an angle of approximately <NUM>°. Therefore, compared with microbead <NUM> in which the marking position A and the triangular coding pattern on the adjacent coding position <NUM> forming an included angle of <NUM>°, the marking position A of the microbead <NUM> is more easily recognized by the computer identification device <NUM>. In addition, the marking position A of the microbead <NUM> with the arc shape is also more easily recognized by the computer identification device <NUM>. Therefore, the marking position A of the microbead <NUM> is more easily distinguished by the computer identification device <NUM> from other corner regions 33b used for positioning, and is more easily recognized by the computer identification device <NUM>. <FIG> shows one code of the microbead <NUM>. It can be understood that different code combinations are formed by engraving triangular code patterns on different code positions <NUM>, thereby forming different codes.

Referring to <FIG>, which are diagrammatic views of a microbead <NUM> after coding according to a fourth embodiment of the present disclosure. The microbeads 40a and 40b in the embodiment are substantially the same as the microbeads <NUM> of the first embodiment and the microbead <NUM> of the third embodiment, respectively, except that the size of the marking position A is further reduced in the fourth embodiment. Since the size of the marking position A is reduced, the number of coding positions <NUM> can be increased, thereby increasing the length of the code. The marking position A of the microbead 40a is formed by cutting the corner region 43a of <NUM>*<NUM>, and the radius of the circle where the marking position A of the microbead 40b is located is <NUM>. It can be understood that both <FIG> only show one code of the microbeads 40a and 40b. By engraving the triangular code patterns at different code positions <NUM>, other codes different from those shown in <FIG> can also be formed.

It can be understood that in other embodiments, the above triangular coding patterns can also be replaced with other types of coding patterns. For example, they can be replaced with rectangular patterns, trapezoidal patterns, etc., or a combination thereof.

Referring to <FIG>, which are diagrammatic views of a microbead before and after coding according to a fifth embodiment of the present disclosure. The microbead <NUM> is a non-circular microbead. Specifically, in the embodiment, the microbead <NUM> is a rectangular microbead, and the code is engraved on the outside of the microbead <NUM>. Furthermore, the microbead <NUM> includes an edge region <NUM> and a central region <NUM> surrounded by the edge region <NUM>. The edge region <NUM> includes corner regions <NUM> and side regions <NUM> besides the corner region <NUM>. The corner regions <NUM> are where the four corners of the rectangle are located. The three corner regions 53a are set to have a shape different from that of the other corner region 53b. Specifically, in the embodiment, the three corner regions 53a are cut to have an obtuse-angle shape of approximately <NUM>°. The other corner region 53b maintains a right-angle shape. It can be understood that setting the three corner regions 53a to be different from the other corner region 53b enables the computer identification device <NUM> to accurately position the microbead <NUM>, so that the three corner regions 53a constitute the positioning device of the microbead <NUM>. The side regions <NUM> are the regions where the long and short sides of the rectangle adjacent to the corner region <NUM> are located. At least one coding position <NUM> is provided on each side region <NUM>, and the coding position <NUM> is used to engrave a code pattern. In the embodiment, the number of the coding positions <NUM> is <NUM> in total. The code pattern may be a rectangle, a triangle, or a combination thereof. <FIG> shows one code of the microbead <NUM>. It can be understood that by engraving triangular code patterns or rectangular code patterns on different code positions <NUM>, and then engraving a single triangular code pattern, a single rectangular code, or a combination thereof on different microbeads <NUM>, the microbead <NUM> can obtain <NUM><NUM>=<NUM> different codes.

Referring to <FIG>, which are diagrammatic views of a microbead before and after coding according to a sixth embodiment of the present disclosure. The microbead <NUM> in the embodiment is substantially the same as the microbead <NUM> in the fifth embodiment, except that three corner regions 63a in the embodiment are provided with positioning devices 631a, and the other corner region 63b is not provided with the positioning device. Specifically, the positioning device 631a may be a positioning hole or a positioning protrusion. The positioning device 631a may be located at the same position of the front and back sides of the microbead <NUM>. In the embodiment shown in <FIG>, the positioning device 631a is a positioning hole penetrating through the front and back sides of the microbead <NUM>, so that the same position of the front and back sides of the microbead <NUM> can be identified by the computer identification device <NUM>. In other embodiments, the positioning device 631a may be a positioning protrusion located at a same position or different positions of the front and back sides of the microbead <NUM>. The positioning device 631a may also be a positioning protrusion located on one side of the microbead <NUM> but not on the other side. By setting the positioning protrusion, when the microbead <NUM> is recognized by the computer identification device <NUM>, no matter the front side or the back side of the microbead <NUM> faces the computer identification device <NUM>, the computer identification device <NUM> can still recognize the predetermined starting position and direction of the code on the microbead <NUM> by the positioning device 631a. <FIG> shows one code of the microbead <NUM>. It can be understood that by engraving triangular code patterns or rectangular code patterns on different code positions <NUM>, and then engraving a single triangular code pattern, a single rectangular code, or a combination thereof on different microbeads <NUM>, the microbeads <NUM> can obtain <NUM><NUM>=<NUM> different codes.

Referring to <FIG>, which are diagrammatic views of a microbead before and after coding according to a seventh embodiment of the present disclosure. The microbead <NUM> in the embodiment is substantially the same as the microbead <NUM> in the first embodiment. Difference is that except for the corner region 73a where the marking position A is located, the corner regions 73b of the microbead <NUM> in the embodiment also set the coding positions <NUM>, thereby increasing the length of the code. <FIG> shows one code of the microbead <NUM>. It can be understood that by engraving the code patterns on the different code positions <NUM> and <NUM>, the microbead <NUM> can obtain more kinds of codes, which improves the utilization rate of the engravable region on the microbead <NUM>.

Referring to <FIG>, which are diagrammatic views of a microbead before and after coding according to an eighth embodiment of the present disclosure which is not part of the invention. The microbead <NUM> is a non-circular microbead. Specifically, in the embodiment, the microbead <NUM> has an oblate shape, and the code is engraved on the outside of the microbeads <NUM>. Furthermore, the microbead <NUM> includes an edge region <NUM> and a central region <NUM> surrounded by the edge region <NUM>. The edge region <NUM> includes two straight side regions <NUM> and two arc side regions <NUM>. Each of the two arc side regions <NUM> connects to two ends of the straight side regions <NUM> extending in the same direction, so that the entire edge region <NUM> has a surrounding structure surrounding the center region <NUM>. A number of coding positions <NUM> and <NUM> are set on both the straight side regions <NUM> and the arc side regions <NUM>. A marking position A is set on the central region <NUM>, which deviates from the center of the central region <NUM>. At the same time, the marking position A has a direction indicator, which is convenient for the computer identification device <NUM> to recognize the front and back sides of the microbead <NUM> and the starting position of the code according to the position and the direction indicator of the marking position A. In the embodiment, the marking position A is a triangular through hole or a triangular protrusion. When the triangular through hole is used as the marking position A, the triangular through hole penetrates the front and back surfaces of the microbead <NUM>. When the triangular protrusion is used as the marking position A, the triangular protrusion needs to be set at the same position of the front and back sides of the microbead <NUM>. In the embodiment, the corner of the triangular through hole or the triangular protrusion pointing to the side arc side region <NUM> can be used as the direction indicator.

<FIG> shows one code of the microbead <NUM>. It can be understood that by engraving the code patterns on the different code positions <NUM> and <NUM>, the microbead <NUM> can obtain a variety of different codes. Since the corner region is removed and replaced by the arc side regions <NUM> connecting to the straight side regions <NUM>, the region of the microbead <NUM> that can be used to engrave the code is further expanded, so that the microbead <NUM> can obtain more different codes.

In other embodiments, the edge region of the microbead may also be the arc side regions, the straight side regions, and the corner regions connected in a direction surrounding the central region, and finally forming the entire edge region surrounding the central region. The positioning positions may be distributed on the arc side regions and the straight side regions, or on the corner regions at the same time.

In other embodiments, the edge region of the microbead may also be the arc side regions and the corner regions connected in a direction surrounding the central region, and finally forming the entire edge region surrounding the central region. The positioning positions may be distributed on the arc side regions or on the corner regions at the same time.

Referring to <FIG>, which is a diagrammatic view of the microbead after coding according to a ninth embodiment of the present disclosure which is not part of the invention. The difference of the embodiment from the above embodiment is that the coding patterns on the microbead <NUM> also has a direction indicator, so as to prevent the computer identification device <NUM> to perform an error recognition due to breakage or shield of the marking position, which makes it impossible to recognize or even incorrectly recognize the direction of the code. Furthermore, since the coding patterns can indicate the direction, the positioning device or the marking position can be omitted. The computer identification device <NUM> can recognize the front and back sides of the microbead <NUM>, the direction of the code, and the starting position of the code based on the direction of the coding pattern, or combined with other factors such as one of the positioning device and the marking position.

In a specific embodiment, the coding pattern has a preset vertex, which deviates to or deviates from a preset direction. The preset direction is preset as the direction of the code. The computer identification device <NUM> recognizes the deviated direction of the preset vertex, thereby recognizing the front and back sides of the microbead <NUM> and the direction of the code.

In the embodiment, the coding pattern is a triangular coding pattern, and the projection h of the vertex <NUM> of triangular coding pattern facing the microbead <NUM> projected on the bottom side opposite to the vertex <NUM> (shown by the dotted line in the figure) does not fall on the midpoint position i of the bottom side. The geometric center X of the coding pattern deviates from the geometric center O of the coding position. Thus, the triangular coding pattern as a whole presents a slanted state, and the vertex <NUM> is deviated to one side rather than being disposed at the center. The deviated direction of the vertex <NUM> is preset as the direction of the code of the microbead <NUM>. After the computer identification device <NUM> recognizes the deviated direction of the preset vertex <NUM> of the triangular coding pattern, the front and back sides of the microbead <NUM>, the direction of the code, and the starting position of the code can be recognized according to the marking position A.

It can be understood that in other embodiments, a coding pattern with the direction indicator can be set on a fixed coding position. The coding pattern indicates the front and back sides of the microbead, the direction of the code, and the starting position of the code through the direction indicator. Other coding patterns are distinguished from the above coding pattern with the direction indicator through the differences of shape, size, orientation, etc. At this time, the computer identification device <NUM> can recognize the front and back sides of the microbead, the direction of the code, and the starting position of the code by identifying the coding pattern with the direction indicator.

It can be understood that, in other embodiments, the directionality of the coding pattern is also used as a constituent factor of the coding. For example, when only the triangular coding patterns are used, each triangular coding pattern can be set to make the vertex to deviate to the left side or to the right side, thereby obtaining two coding combinations. It can be understood that the left deviation and the right deviation here are only used to describe different directions of the vertexes of the triangular coding pattern, and do not have further meaning to limit the present disclosure. Therefore, in different embodiments, the code of the microbead can be obtained by combining one or more constituent factors such as the shape, the size, and the direction of the coding patterns.

It can be understood that the microbeads are set to be rectangular or oblate in the above embodiments, and coding patterns are cut out on the periphery of the rectangular or oblate microbeads to form different codes. In other embodiments, the shapes of the microbeads can also be elliptical, trapezoidal, irregular, or other shapes deviating from circular. Since the shape of the microbead deviates from circular, compared to the circular microbead, a ratio of the overall surface area of the non-circular microbead with respect to the perimeter of the microbead before coding is smaller, and more coding positions can be set on the same consumable region, or the size of the consumable region can be reduced by setting a same number of coding positions. Thus, the utilization rate of microbeads can be improved. Furthermore, in some embodiments, as shown in the first, the second, the fourth, and the eighth embodiments described above for example, the microbead may have a first length in a first dimensional direction and a second length in a second dimensional direction perpendicular to the first dimensional direction. The first length is longer than the second length. The microbead further has a central region and an edge region surrounding the central region in the plane formed by the first dimensional direction and the second dimensional direction. The edge region is provided with coding positions for engraving the codes. Since the ratio of the first length to the second length increases, the ratio of the overall surface region of the microbead before coding to the perimeter of the microbead before coding can be further reduced, and the utilization rate of the microbead can be further improved.

Referring to <FIG>, which is a diagrammatic view of a computer identification device <NUM> for identifying the code of the microbead. The computer identification device <NUM> includes an image capturing module <NUM> and a code identification module <NUM>. The image capturing module <NUM> is used to capture an image of the microbead <NUM>. The code identification module <NUM> is used to identify the front and back sides of the microbead <NUM>, the starting position of the code, and the direction of the code based on the marking position of the microbead <NUM>, the positioning device, the direction indicator of the code patterns, or a combination thereof. The code identification module <NUM> is further used to identify the code of the microbead <NUM> according to the coding pattern on each coding position. The microbead <NUM> can be the microbead in the above embodiment or another microbead that have been appropriately modified but still fall within the scope of the disclosure. The image capturing module <NUM> may be a CMOS camera, a CCD camera, an infrared camera, or the like.

The code identification module <NUM> identifies the code of the microbead <NUM> according to the code pattern on each coding position. Specifically, when the code on the microbead <NUM> has only one code pattern, the code identification module <NUM> identifies whether the coding position is recessed or not to determine whether the coding position is engraved with the code pattern. When the code on the microbead <NUM> has two or more code patterns, the code identification module <NUM> identifies the preset characteristics of each code pattern. For example, when the coding patterns have triangle or rectangle at the same time, in an embodiment, the coding identification module <NUM> first identifies whether one coding position is recessed, and when the coding position is recessed, then further identifies whether the code patten is triangle or rectangle according to a distance from a specific point of the edge of the coding position to another specific point inside the recess. The above specific point is predefined and input into the computer identification device <NUM> as a preset parameter or preset condition.

It can be understood that the computer identification device <NUM> may also include a suitable processing unit and a storage unit to complete the microbead code identification function required by the computer identification device <NUM>.

It can be understood that the processing unit of the computer identification device <NUM> can execute a software program. The storage unit stores the software program executed by the processing unit, and can simultaneously store result data obtained by the processing unit executing the software program, so as to realize the microbead code identification function. The code identification module <NUM> appearing above is a summary and a description of the microbead code identification function realized by the computer identification device <NUM> executing the software program.

Claim 1:
A microbead (<NUM>, <NUM>, <NUM>, 40a, 40b, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) with a code engraved on an outside of the microbead (<NUM>, <NUM>, <NUM>, 40a, 40b, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>), the microbead (<NUM>, <NUM>, <NUM>, 40a, 40b, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) comprising:
a central region (<NUM>, <NUM>, <NUM>); and
an edge region (<NUM>, <NUM>, <NUM>) surrounding the central region (<NUM>, <NUM>, <NUM>), an outer contour of the edge region (<NUM>, <NUM>, <NUM>) before and after engraving the code is non-circular, the edge region (<NUM>, <NUM>, <NUM>) comprising a plurality of coding positions (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>), the code of the microbead (<NUM>, <NUM>, <NUM>, 40a, 40b, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) is engraved on the plurality of coding positions (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>), and each bit of the code corresponds to each of the plurality of coding positions (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>);
the outer contour of the edge region (<NUM>, <NUM>, <NUM>) is rectangular, the edge region (<NUM>, <NUM>, <NUM>) comprises corner regions (<NUM>, 13a, 13b, 23a, 33a, 33b, 43a, <NUM>, 53a, 53b, 63a, 63b, 73a, 73b) and side regions (<NUM>, <NUM>), the corner regions (<NUM>, 13a, 13b, 23a, 33a, 33b, 43a, <NUM>, 53a, 53b, 63a, 63b, 73a, 73b) are where four corners of the rectangle are located, the side regions (<NUM>, <NUM>) are where the long and short sides of the rectangle adjacent to the corner regions (<NUM>, 13a, 13b, 23a, 33a, 33b, 43a, <NUM>, 53a, 53b, 63a, 63b, 73a, 73b) are located, and the corner regions (<NUM>, 13a, 13b, 23a, 33a, 33b, 43a, <NUM>, 53a, 53b, 63a, 63b, 73a, 73b) and the side regions (<NUM>, <NUM>) are connected to each other in a direction surrounding the central region (<NUM>, <NUM>, <NUM>);
characterized in that, the corner regions (13a, 13b, 23a, 33a, 33b, 43a, 53a, 53b, 63a, 63b, 73a, 73b) are provided with positioning devices and/or marking positions (A), and the positioning devices and/or the marking positions (A) are configured to allow a computer identification device (<NUM>) to identify a front side and a back side of the microbead (<NUM>, <NUM>, <NUM>, 40a, 40b, <NUM>, <NUM>, <NUM>, <NUM>), a starting position of the code, and a direction of the code.