CN114994082A - A double-precision mark point graphic structure and recognition method - Google Patents

Abstract

A double-precision mark point pattern structure and an identification method are disclosed, wherein a mark point is composed of a large ring, a small ring and a solid circle; big ring, little ring and solid circle three are concentric to by interior outside is in proper order: the solid ring, the small ring and the large ring are not in contact with each other; the diameter of the solid circle 3 is 0.7 mm; the inner diameter of the small circular ring 2 is 1.5mm, and the outer diameter is 1.8 mm; the inner diameter of the large circular ring 1 is 3.4mm, and the outer diameter is 4.0 mm; when the ink is coated, the ink coating 4 is positioned in the large circular ring, covers the solid circle 3 and the small circular ring 2 and does not exceed the inner diameter of the large circular ring 1; through exposing the printing ink picture layer, can compare with the position of solid circle and little ring according to the development after the printing ink picture layer is exposed, can judge two kinds of precisions simultaneously, compare in the traditional mark that can only judge a precision, when another kind of precision need be judged, need increase another group mark point, this mark point practices thrift the PCB space more, has improved the utilization ratio in PCB space.

Description

A double-precision mark point graphic structure and recognition method

technical field

The invention relates to the field of circuit board printing, in particular to a double-precision mark point graphic structure and an identification method.

Background technique

After the components on the PCB are installed, it is usually necessary to use the mark points to check the patch accuracy. However, the existing mark points can only monitor and identify one accuracy, and cannot meet the two accuracy requirements. If there are components with two kinds of precision requirements, it is necessary to make two kinds of precision mark points to check whether the two kinds of precision requirements are met, which takes up too much space on the PCB. Therefore, the present invention proposes a double-precision mark. Point pattern recognition structure and recognition method, it can recognize two kinds of precision, when there are two kinds of precision requirements on a PCB board, there is no need to add another kind of mark point to identify another kind of precision, through this mark point The two precision requirements can be identified at the same time, which saves the space of the PCB and improves the space utilization of the PCB.

SUMMARY OF THE INVENTION

The technical scheme adopted in the present invention is: a double-precision mark point graphic structure, characterized in that the mark point is composed of a large circle, a small circle and a solid circle; the large circle, the small circle and the solid circle are three They are concentric, and from the inside to the outside are: solid circle, small circle, large circle, and none of the three are in contact.

Further, the diameter of the solid circle is greater than 0.1 mm; the difference between the outer diameter and the inner diameter of the small circular ring is greater than 0.15 mm.

Further, the distance from the solid circle edge to the inner edge of the small circle is greater than 0.2 mm; the distance from the outer edge of the small circle to the inner edge of the large circle is greater than 0.2 mm.

A double-precision mark point recognition method, comprising the following steps:

S1. Apply the ink layer to the large ring, and cover the small ring and the solid circle;

S2. Expose the ink layer;

S3. Observe the mark points after exposure, and judge the accuracy deviation according to the position of the ink layer developed after exposure.

Further, the exposure light source is a circular ring, the diameter of the outer edge of the light source is smaller than the outer diameter of the small ring, and is larger than the inner diameter of the small ring; the diameter of the inner edge of the light source is smaller than the diameter of the solid circle.

Because the present invention adopts the above-mentioned technical scheme, the present invention has the beneficial effects that the traditional mark points can only identify one kind of precision. The mark point can identify two kinds of precision at the same time, no need to increase the mark point, which greatly saves the PCB space.

Description of drawings

1 is a schematic diagram of the positional relationship between a large ring, a small ring and a solid circle in the present invention.

Figure 2 is a schematic diagram of the ink coating style of the present invention.

FIG. 3 is a schematic diagram of the pattern of the exposure light source of the present invention.

FIG. 4 is a schematic diagram of the present invention after the mark point is coated with an ink layer.

FIG. 5 is a schematic diagram of the size ratio of the exposure light source and each part of the mark point.

FIG. 6 is a schematic diagram of the ideal state after exposure of the present invention.

FIG. 7 is a schematic diagram of the present invention when the precision deviation after exposure is greater than 0 and less than 0.05 mm.

8 is a schematic diagram of the present invention when the precision deviation after exposure is equal to 0.05mm.

9 is a schematic diagram of the present invention when the precision deviation after exposure is greater than 0.05mm and less than 0.075mm.

10 is a schematic diagram of the present invention when the precision deviation after exposure is equal to 0.075mm.

11 is a schematic diagram of the present invention when the precision deviation after exposure is greater than 0.075mm.

reference number

Large circle-1; small circle-2; filled circle-3; ink layer-4; ink layer filled circle-41; ink layer circle-42.

Detailed ways

Example, after the PCB patch is completed, check the PCB to check whether the patch accuracy meets the requirements. The following is to check the patch accuracy when there are patches with two precision requirements of 0.05mm and 0.075mm on the PCB. give an example;

As shown in Figure 1-5, a double-precision mark point graphic structure, the mark point consists of a large circle, a small circle and a solid circle; the large circle 1, the small circle 2 and the solid circle 3 are concentric, and From inside to outside, the order is: solid circle 3, small circle 2, large circle 1, and none of them are in contact; the diameter of solid circle 3 is greater than 0.1mm; the difference between the outer diameter and inner diameter of small circle 2 More than 0.15mm, the distance from the edge of the solid circle 3 to the inner edge of the small circle 2 is greater than 0.2mm; the distance from the outer edge of the small circle 2 to the inner edge of the large circle 1 is greater than 0.2mm;

The diameter of the solid circle 3 is 0.7mm; the inner diameter of the small circle 2 is 1.5mm and the outer diameter is 1.8mm; the inner diameter of the large circle 1 is 3.4mm and the outer diameter is 4.0mm; the ink coating layer 4 is located in the large circle, covering the solid circle 3 and Small ring 2, and does not exceed the inner diameter of large ring 1;

A double-precision mark point recognition method, the recognition method is as follows:

First, apply the ink on the mark point, and the ink layer 4 is located in the large circle 1, covering the small circle 2 and the solid circle 1, and does not exceed the inner diameter of the large circle 1; Ring, with an inner diameter of 0.6mm and an outer diameter of 1.65mm;

Under ideal conditions, the distance from the outer edge of the exposure light source to the outer edge of the small ring should be 0.075mm. The distance from the inner edge of the exposure light source to the edge of the solid circle 3 should be 0.05mm, and the exposure is carried out at this time. The image obtained after the exposure should be as shown in Figure 6. The distance between the edge of the solid circle 3 and the edge of the solid circle 41 of the remaining ink layer after exposure is completed. The distance should be 0.05mm, and the distance between the inner edge of the small ring 2 and the inner edge of the remaining ink layer ring 42 after exposure should be 0.075, which means that the exposure is in an ideal state and there is no deviation;

When the deviation is greater than 0 and less than 0.05mm, the obtained image should be, as shown in Figure 7, the minimum distance from the edge of the solid circle 3 to the edge of the solid circle 41 of the remaining ink layer after exposure is less than 0.05mm and greater than 0.

When the deviation is equal to 0.05mm, the obtained image should be, as shown in Figure 8, the edge of the solid circle 3 is tangent to the remaining ink layer solid circle 41 after exposure, and the ink layer solid circle 41 is located in the solid circle 3;

When the deviation is greater than 0.05mm and less than 0.075mm, the obtained image should be, as shown in Figure 9, the edge of the solid circle 41 of the ink layer exceeds the solid circle 3, and the inner edge of the ink layer circle 42 is located within the outer edge of the small circle 2 ;

When the deviation is equal to 0.075mm, the obtained image should be, as shown in Figure 10, the inner edge of the ink layer ring 42 is tangent to the outer edge of the small circle 2, and the inner edge of the ink layer circle 42 does not exceed the small circle the outer edge of ring 2;

When the deviation is greater than 0.075mm, the obtained image should be, as shown in Figure 11, the inner edge of the ink layer ring 42 beyond the outer edge of the small ring 2;

Working principle: When there are two components with precision requirements of 0.05mm and 0.075mm on the PCB board, check whether the components with the two precision requirements meet the precision requirements on the PCB board. Under the exposure machine that exposes the mark, the positioning is based on the reference points around the PCB board. After the positioning is completed, the exposure machine is started to expose the mark points. After the exposure is completed, the PCB board is taken out and placed for inspection. Observe under the microscope at the mark point to judge whether it is qualified or not; for example: when the accuracy requirements of the two components on the PCB are 0.05mm and 0.075mm respectively, after exposure, if the observed image is as shown in Figure 9 or Figure 9 10, that is, when the edge of the solid circle 41 of the ink layer exceeds the solid circle 3, and the inner edge of the ink layer ring 42 is located within the outer edge of the small ring 2, or the inner edge of the ink layer ring 42 and the outer edge of the small ring 2 When the edges are tangent, it means that the accuracy deviation is not more than 0.075mm, that is, the components with the accuracy requirement of 0.075mm are qualified, and the components with the accuracy requirement of 0.05mm are not qualified; if the observed images are shown in Figure 6, Figure 7, When any of the graphs in Figure 8 are shown, it means that the accuracy deviation does not exceed 0.05mm, which means that both accuracy requirements are met; if the observed image is shown in Figure 11, it means that the accuracy deviation is greater than 0.075. mm, two components with different precision requirements are not qualified.

Although the embodiments of the present invention have been shown and described above, it should be understood that the above-mentioned embodiments are exemplary and should not be construed as limiting the present invention. Embodiments are subject to variations, modifications, substitutions and variations.

Claims (5)

1. A double-precision mark point pattern structure is characterized in that mark points are composed of large circular rings, small circular rings and solid circles; big ring, little ring and solid circle three are concentric to by interior outside is in proper order: solid circle, small circle, big circle, and all do not contact between the three.

2. A dual precision mark dot pattern structure as claimed in claim 1, wherein said solid circle has a diameter greater than 0.1 mm; the difference between the outside diameter and the inside diameter of the small circular ring is larger than 0.15 mm.

3. A dual precision mark dot pattern structure as claimed in claim 2, wherein the distance from the edge of said solid circle to the inner edge of said small circle is greater than 0.2 mm; the distance from the outer edge of the small circular ring to the inner edge of the large circular ring is more than 0.2 mm.

4. A double-precision mark point identification method is characterized by comprising the following steps:

s1, coating an ink layer in the large circular ring, and covering the small circular ring and the solid circle;

s2, exposing the ink layer;

and S3, observing the exposed mark points, and judging the precision deviation according to the position of the development of the ink layer after exposure.

5. The method of claim 4, wherein the exposure light source is circular, and the outside edge diameter of the light source is smaller than the outside diameter of the small ring and larger than the inside diameter of the small ring; the diameter of the inner edge of the light source is smaller than that of the solid circle.

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