CN1122172C - System and Method for Measuring Image Sensing Die Offset - Google Patents

Abstract

A system for measuring the offset of image sensor chip includes a test pattern with a predetermined pattern. A contact image sensor module has a plurality of sensor chips arranged in a row, each sensor chip is configured with a plurality of sensors, which includes sensors located at the end points of two adjacent sensor chips. The control system is used for controlling the driving device to enable the sensor module to move relative to the test chart in a set direction, the sensor module scans the test chart and obtains signal waveforms sensed by the end point sensors of two adjacent sensing chips, and the distance between the end point sensors of the two adjacent sensing chips is calculated according to the signal waveforms.

Description

System and method for measuring image sensor chip deflection

technical field

The present invention relates to a measurement system, in particular to a system for measuring contact image sensor chip shift.

Background technique

In terms of general image scanning devices, taking image scanners as an example, the following three components are often used to capture the image of a document (subject document), such as a light source for illuminating the document, an image sensor ( image sensor), an optical system that focuses the document image on the image sensor. The early image sensor array (image sensor array) is formed by charge-coupled device (CCD; charge-coupled device).

However, taking an image scanning device that reads an A4 file (210mm wide) as an example, the lens system must reduce the image of the A4 file to a level that the image sensor of the charge-coupled device can accept. The optical distance is about 300mm, so the volume of the entire image scanning device becomes very large. If the refraction of the mirror is used to reduce the volume of the device, the quality is easily affected by temperature changes and mechanical stress.

Therefore, a contact image sensor (CIS; contact image sensor) is gradually replacing the image sensor of the aforementioned charge-coupled device. Since the width of the contact image sensor is arranged to be the same as that of the A4 document, it only needs to be used such as A double optical lens is used to project the document image on the contact image sensor to obtain the image data. Therefore, not only the structure is relatively simple, but the volume of the image scanning device is also greatly reduced.

As shown in FIG. 1 , the contact image sensor module 20 (module) generally first arranges an image sensor chip (image sensor chip) on a panel (main board) 10. A shorter image sensor chip such as 12, 14 and 16 is arranged in a row. Then manually measure each image sensor chip 12 , 14 or 16 through a microscope to determine whether there is any deviation, and then fix it in a frame 15 and seal it with glue.

However, when these contact image sensor modules 20 are applied to an image scanning device (scanner), if it is found that the scanned images have gaps or discontinuities, due to the image sensor chips 12, 14 and 16 It has been packaged in the frame 15 along with the panel 10, so when it is suspected that the aforementioned phenomenon is caused by the deviation of the image sensing chip, the only way to use destructive measurement is to disassemble the frame 15 and directly examine the image sensing chip with a microscope To observe, but the contact image sensor module has also been damaged and cannot be used.

Contents of the invention

In view of this, the purpose of the present invention is to solve the above problems, and propose a system for measuring the offset of image sensing chips, which uses image processing (image processing) to measure the offset of the distance between each image sensing chip . Even if the contact image sensor module has been sealed and fixed, the offset of the distance between each image sensor chip can be measured without destroying its structure and function.

To achieve the above objectives, the present invention provides a system for measuring the displacement of an image sensor chip, which includes a test pattern with a predetermined pattern. A contact image sensor module, including a plurality of sensing chips arranged in a row, each sensing chip is equipped with a plurality of sensors, including sensors located at the ends of two adjacent sensing chips; a drive device; and a control system, used to control the driving device, so that the contact image sensor module moves in a predetermined direction relative to the test pattern, and the sealed image sensor module scans the test pattern to obtain The signal waveforms sensed by the two sensors for sensing the end points of the chip are calculated, and the distance between two adjacent sensors for sensing the end points of the chip is calculated.

The present invention provides another method for measuring the offset of an image sensing chip, which includes the following steps: providing a contact image sensor module, which includes a plurality of sensing chips arranged in a row, and each sensing chip is configured There are multiple sensors; a test pattern with a predetermined pattern is provided; the contact image sensor module is moved in a predetermined direction relative to the test pattern, and the test pattern is scanned; the signal waveform sensed by the sensor; and calculating the distance between the sensors of two adjacent sensing chip endpoints.

The predetermined direction includes the direction of the vertical test chart, or the direction of the horizontal test chart. The predetermined pattern of the test chart is black and white stripes, wherein the black and white stripes are horizontal stripes or diagonal stripes, and the width of the black and white stripes can be equal or unequal width.

In addition, when scanning, the contact image sensor module can move the test pattern with a predetermined pattern in a predetermined direction to scan; the contact image sensor module can also be scanned by the test pattern with a predetermined pattern. Scanning is performed by moving in a predetermined direction; the image sensor module can also be scanned with a test pattern synthesized by light (such as laser, etc.). The aforementioned predetermined direction also includes a direction that makes the contact image sensor module and the test pattern form a predetermined angle.

When the black stripe is scanned, the corresponding signal waveform is a low-brightness area, and when the white stripe is scanned, the corresponding signal waveform is a high-brightness area, and when the sensor covers part of the black and white stripes, its The corresponding signal waveform brightness is between the high brightness area and the low brightness area.

Another way to calculate the distance between the sensors at the endpoints of two adjacent sensing wafers is to translate the signal waveforms sensed by the sensors at the endpoints of two adjacent sensing wafers until they overlap, and calculate the translation distance, In order to obtain the horizontal distance or the vertical distance between the sensors sensing the end points of two adjacent wafers.

Description of drawings

A preferred embodiment of the present invention will be described below with reference to the accompanying drawings. In the attached picture

FIG. 1 shows a schematic diagram of a contact image sensor module;

FIG. 2A represents a flow chart of a method for measuring the offset of an image sensing wafer according to the present invention;

FIG. 2B is a block diagram of an embodiment of a system for measuring image sensor wafer deflection provided in FIG. 2A;

Fig. 3 shows the use of an embodiment of the present invention to scan in the direction perpendicular to the test pattern to obtain a signal waveform composed of brightness changes sensed by a sensor at the end of a single sensing chip;

FIG. 4 shows a schematic diagram of a signal waveform composed of brightness changes measured by sensors that do not shift the endpoints of two adjacent sensing chips by scanning in a direction perpendicular to the test pattern using an embodiment of the present invention;

5 and 6 show a schematic diagram of a signal waveform composed of luminance changes sensed by sensors that shift the endpoints of two adjacent sensing chips by scanning in a direction perpendicular to the test pattern using an embodiment of the present invention;

7 represents another embodiment of the present invention, a schematic diagram of scanning by the contact image sensor module in the direction perpendicular to the test pattern with diagonal stripes;

FIG. 8 is a diagram showing the relative positions of each sensor and the test chart with oblique stripes during the scanning process according to the embodiment of FIG. 7;

FIG. 9A is a schematic diagram of signal waveforms sensed by each sensor according to the relative positions of FIG. 8; and

FIG. 9B is a schematic diagram of signal waveforms corresponding to the translation sensor until overlapping according to FIG. 9A .

Detailed ways

Please refer to FIG. 2A , which shows a method for measuring image sensor chip displacement of the present invention, which includes the following steps:

First, according to step S10 , a contact image sensor module is provided, which includes a plurality of sensing chips arranged in a row, and each sensing chip is configured on a plurality of sensors.

Secondly, according to step S20, a test pattern with a predetermined pattern is provided.

Next, in step S30 , the contact image sensor module is moved relative to the test chart in a predetermined direction for scanning.

Then according to step S40, the signal waveforms sensed by the sensors located at the ends of two adjacent sensing chips are obtained.

According to step S50 , the distance between the endpoint sensors of two adjacent sensing chips is calculated.

Please refer to FIG. 2B , which shows a system for measuring the deflection of an image sensor chip according to an embodiment of the aforementioned method of the present invention. It includes a test chart 30 with a predetermined pattern, such as black stripes 32 , 34 , 36 in FIG. 3 and a white stripe 38 , 38 b alternating with each other. A contact image sensor module 20 mainly includes a plurality of sensor chips arranged in a row, as shown by the reference numerals 12, 14, and 16 in FIG. 1, and each sensor chip is configured with a plurality of sensors, Including the sensors located at the endpoints of two adjacent sensing chips, such as P1 and P2 in FIG. 4 , the resolution of the contact image sensor module 20 is determined according to the manufacturer's specifications. A driving device 50, such as a step motor, can select a step scale with a resolution higher than that of the CIS module 20 for measurement. A control system 40, such as using a microprocessor with image processing and calculation functions, can be used to control the driving device 50 to drive the contact image sensor module 20 to scan the test pattern 30 in a predetermined direction, and obtain the image located adjacent to it. The signal waveforms measured by the two sensors P1 and P2 sensing the endpoints of the wafer are shown in Figure 6, and the distance between two adjacent sensors sensing the endpoints of the wafer is calculated, for example, the distance Δy in the vertical direction y (or the spacing Δx in the horizontal direction). The distance is calculated based on the center point of the sensor.

In the embodiment of FIG. 2B , the driving device 50 is used to drive the contact image sensor module 20 to scan the test pattern 30 in a predetermined direction. However, it should be noted that, in the spirit of the present invention, as long as there is relative movement between the contact image sensor module and the test pattern. For example, the driving device can also be used to drive the test pattern to move in a predetermined direction to the contact image sensor module for scanning.

See Figure 3. This figure takes the vertical direction y of the test pattern 30 as an example to illustrate the predetermined pattern of the test pattern 30 by the contact image sensor module 20, such as the area where the horizontal black stripes 32, 34, 36 and white stripes 38, 38b alternate. , when scanning in the y direction, the signal waveform Vp sensed by the sensor P located at the end point of the sensing wafer 12 is obtained, wherein the horizontal axis represents the distance in the y direction, and the vertical axis represents the brightness change. As for the scanning method, the panel 10 of the contact image sensor module 20 can be moved in a predetermined direction relative to the test pattern 30 to scan; the interference fringes synthesized by light (such as laser) can also be used as the test pattern 30 to obtain the test pattern 30. The panel 10 of the image sensor module 20 is scanned. When black stripes such as 32, 34, and 36 are scanned, the corresponding signal waveform is a low-brightness area, and when white stripes 38 are scanned, the corresponding signal waveform is a high-brightness area. As for when the sensor covers part of the black stripes Such as 32, 34 and part of the white stripe 38, the brightness of the corresponding signal waveform is between the high brightness area and the low brightness area.

Please refer to FIG. 4, for two adjacent sensing chips 12, 14 on the panel 10, assuming that the sensors P1, P2 located at the endpoints of the adjacent two sensing chips have no error in the vertical direction y, then scanning Afterwards, the signal waveforms Vp1 and Vp2 of the sensors P1 and P2 located at the ends of the adjacent two sensing chips 12 and 14 are obtained. Since P1 and P2 pass through the black stripes 32 and 34 and the white stripes 38 therebetween at the same time, the signal waveforms The waveforms Vp1, Vp2 are almost overlapped.

However, referring to FIG. 5 , when the sensors P1 and P2 located at the endpoints of two adjacent sensing chips 12 and 14 have a substantial error Δy in the vertical direction y, then after scanning, the sensors P1 and P2 located at the two adjacent sensing chips are scanned. The signal waveforms Vp1 and Vp2 of the sensors P1 and P2 at the ends of the chips 12 and 14 pass through the horizontal black stripes 32 and 34 and the white stripes 38 therebetween. Therefore, the brightness regions corresponding to the signal waveforms Vp1 and Vp2 do not overlap but have a predetermined distance from each other.

Please refer to Fig. 6, which are the signal waveforms Vp1 and Vp2 corresponding to the sensors P1 and P2. Since the predetermined separation distance is the actual error Δy of the sensors P1 and P2 in the vertical direction y, the calculation of the adjacent two One of the ways to sense the distance Δy between the sensors P1 and P2 at the endpoints of the wafers 12 and 14 is to use the signal waveform Vp1 corresponding to the translation sensor P1 to the signal waveform Vp2 corresponding to P2, or the signal corresponding to the translation sensor P2 Waveforms Vp2 to P1 correspond to the signal waveform Vp1 until the two overlap, and calculate the translation distance to obtain the vertical spacing value Δy. Similarly, if the test pattern 30 is rotated 90 degrees, the scanning direction is changed to the horizontal direction x, and the measurement is performed according to the above-mentioned embodiment, the horizontal distance value Δx can be obtained.

Another embodiment of the method for measuring the offset of an image sensing wafer according to the present invention is described below.

Please refer to FIG. 7 , which takes the vertical direction y as an example, and makes the contact image sensor module 20 and the test pattern 70 form a predetermined angle θ, for example, 45 degrees, to illustrate how the contact image sensor module 20. When scanning the predetermined pattern of the test chart 70 in the vertical y-direction, such as the area between the black stripes 72, 74 and the white stripes 78 obliquely, the adjacent sensors P0, P1 located at the end points of the sensing wafer 12 are obtained. The sensed signal waveforms Vp0 , Vp1 ′, and the signal waveform Vp2 ′ of the sensor P2 located at the end of the sensing wafer 14 . Among them, the scanning method can be to use the panel 10 of the contact image sensor module 20 to scan the test pattern 70 in a predetermined direction, for example, the scanning direction of the vertical direction y with oblique black stripes, or the horizontal black stripes. The scanning direction has an oblique angle θ with the vertical direction y; in addition, the panel 10 of the image sensor module 20 can also be scanned by the test pattern 70 synthesized by light such as laser light. Therefore, when the sensor scans black stripes such as 72 and 74, the corresponding signal waveform is a low-brightness area, and when the sensor scans a white stripe 78, the corresponding signal waveform is a high-brightness area. When the device covers some black stripes such as 72, 74 and white stripe 78, the brightness of the corresponding signal waveform is between the high-brightness area and the low-brightness area.

Please also refer to FIG. 8 and FIG. 9A, which show the relative positions of the sensors P0, P1, P2 and the diagonal black stripes 72, 74 and white stripes 78 during scanning, and the relative positions of the sensors P0, P1, P2 Correspondingly formed signal waveforms Vp0', Vp1', Vp2'. Wherein when the sensors P1 and P2 located at the endpoints of two adjacent sensing chips 12 and 14 have a vertical distance Δy in the vertical direction y and a horizontal distance Δx in the horizontal direction x, then during the scanning process, the sensors located at the adjacent The signal waveforms Vp0', Vp1', Vp2' sensed by the sensors P0, P1, and P2 at the endpoints of the two sensing chips 12, 14 will be different due to the order of successively passing through the black stripes 72, 74 and the white stripes 78 therebetween. Not overlapping together, for example, if the white stripe 78 is used as a reference, the first to scan the white stripe 78 is the sensor P2 , the second is the sensor P1 , and the last is the sensor P0 . Therefore, the signal waveforms Vp0 ′, Vp1 ′, Vp2 ′ corresponding to the brightness change Vout do not overlap but have a predetermined distance from each other.

In addition, in FIG. 8, three relative positions Y1, Y2, and Y3 are taken as an example, and the horizontal distances of the sensors P0-P1 and P1-P2 are Δx ₀ and Δx, respectively. In addition, the line connecting the center points of the sensors P0 and P1 in the contact image sensor module is defined as the direction of the x-axis, and the oblique lines of the test pattern 70 form a predetermined angle θ with the x-axis. Secondly, when the sensors P2, P1, and P0 successively reach the white stripe 78, define the vertical distance between the first position Y1 and the second position Y2 as Δy′, and the vertical distance between the second position Y2 and the third position Y3 as Δy ₀ , And the vertical distance between the center point of the sensor P1 of the sensing chip 12 in the second position Y2 and the center point of the sensor P2 of the sensing chip 14 in the first position Y1 is defined as Δy ₁ . This gives the following formula:

Δy ₀ /Δx ₀ =tanθ=Δy ₁ /Δx-------(1)

Δy'=Δy ₁ +Δy------------------(2)

Therefore, when the included angle is 45 degrees, formula (1) can be changed to:

Δy ₀ /Δx ₀ =1=Δy ₁ /Δx----------(3)

Returning to FIG. 9A, for the oblique black stripes such as the white stripes between 72 and 74, the sensor P2 scans this area first to form a high brightness area, followed by the sensor P1, and then the sensor P1. Sensor P0. Therefore, the signal waveforms Vp0', Vp1', Vp2' of the sensors P0, P1, P2 can be obtained, wherein the distance relative to the signal waveform Vp0'-VP1' is Δy ₀ , and the distance between the signal waveform Vp1'-Vp2' The spacing is Δy ¹ .

That is, referring to FIG. 9B, if the signal waveforms Vp0' to Vp1' are translated until they overlap, the translation distance can be calculated to obtain the distance value Δy ₀ . Similarly, the signal waveforms Vp1' to Vp2' can be translated until they overlap. Until overlapping, the translation distance can be calculated to obtain the distance value Δy′.

Therefore, according to formula (3), when the included angle is 45 degrees, it can be obtained:

Δx ₀ =Δy ₀ , Δx=Δy ₁ --------(4)

In addition, according to formula (2) and formula (4), we can get:

Δx=Δy′-Δy-----------(5)

Due to the aforementioned embodiment, as shown in FIG. 6 , the vertical distance value Δy can be obtained, therefore, the horizontal distance value Δx can be obtained by the formula (5). In this way, two sets of horizontal and oblique black and white stripes can be used, and the contact image sensor module only needs to scan the y-axis direction to obtain the offset values Δx and Δy between the sensing chips, so the drive mechanism can be simplified the complexity.

In other words, the method for measuring the offset of the image sensor chip according to the present embodiment includes the following steps:

First, as shown in FIGS. 1, 5, and 6, a contact image sensor module 20 is provided, including a plurality of sensing chips 12, 14, 16 arranged in a row, and each sensing chip is configured with a plurality of sensing chips. Then provide a first test pattern 30, which has horizontal black and white stripes 32, 38, 34; then the contact image sensor module 20 aligns the first test pattern 30 with a vertical direction y Carry out scanning; Obtain the signal waveforms Vp1, Vp2 sensed by the sensors P1, P2 located at the endpoints of two adjacent sensing chips such as 12, 14; and calculate the sensing of the endpoints of the adjacent two sensing chips according to the signal waveforms Vp1, Vp2 The vertical distance Δy of the device.

Next, as shown in Figures 7 to 9, a second test pattern 70 is provided, which has test areas with diagonal stripes 72 and 74 alternately; 70 to scan, the vertical direction and oblique stripes 72, 74 have an inclination angle θ, such as 45 degrees; obtain at least three sensors P0, P1, P2 located at the endpoints of two adjacent sensing chips such as 12, 14 Sensed signal waveforms Vp0', Vp1', Vp2'; and according to the vertical spacing Δy, the signal waveforms Vp0', Vp1', Vp2' sensed by these at least three sensors P0, P1, P2, and the inclination angle θ calculates the horizontal distance Δx between the sensors P1 and P2 that sense the endpoints of two adjacent wafers.

Therefore, the spacing values Δx and Δy obtained according to the embodiment of the present invention are the horizontal and vertical offset values of two adjacent sensing chips, so they can replace the traditional destructive measurement method, and the horizontal and vertical offset values can be corrected through the repair software. The vertical offset value is compensated to improve the scanned image.

Although the present invention has been disclosed above in conjunction with a preferred embodiment, it is not intended to limit the present invention. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the present invention The scope of protection shall be defined by the appended claims.

Claims (22)

1. measure the system that image sensing wafer is offset for one kind, comprising:

One test pattern has a set pattern;

One contact-type image sensing device module, it has many sensing wafers that form a line, and this each sensing wafer disposes a plurality of sensors, comprises the sensor that is positioned at adjacent two sensing wafer end points;

One drive unit; And

One control system, in order to control this drive unit, this contact-type image sensing device module and this test pattern are produced in a set direction to relatively move, this contact-type image sensing device module will scan this test pattern, obtaining the sensor institute sensed signal waveform that is positioned at these adjacent two sensing wafer end points, and calculate the spacing of the sensor of these adjacent two sensing wafer end points.

2. the system as claimed in claim 1, wherein this drive unit is used for driving this contact-type image sensing device module, and this contact-type image sensing device module is moved relative to this test pattern with a set direction.

3. the system as claimed in claim 1, wherein this drive unit is used for driving this test pattern, and this test pattern is moved relative to this contact-type image sensing device module with a set direction.

4. as claim 1,2, one of 3 described systems, wherein this set direction is a vertical direction.

5. system as claimed in claim 4, wherein the spacing of the sensor of these adjacent two sensing wafer end points is a vertical interval.

6. as claim 1,2, one of 3 described systems, wherein this set direction is a horizontal direction.

7. system as claimed in claim 6, wherein the spacing of the sensor of these adjacent two sensing wafer end points is a level interval.

8. a method of measuring the image sensing wafer skew comprises the following steps:

One contact-type image sensing device module is provided, and it comprises many sensing wafers that form a line, and each sensing wafer disposes a plurality of sensors;

One test pattern with set pattern is provided;

This contact-type image sensing device module moves with respect to this test pattern with a set direction, and scans this test pattern;

Obtain the sensor sensed signal waveform that is positioned at adjacent two sensing wafer end points; And

Calculate the spacing of the sensor of these adjacent two sensing wafer end points.

9. method as claimed in claim 8 wherein when scanning, is moved with a set direction with respect to this test pattern by this contact-type image sensing device module, to scan.

10. method as claimed in claim 8 wherein when scanning, is moved with a set direction with respect to this contact-type image sensing device module by this test pattern, to scan.

11. method as claimed in claim 8, wherein when scanning, the test pattern synthetic by light comes this contact-type image sensing device module is scanned.

12. as claim 8,9,10, one of 11 described methods, wherein this set direction comprises the direction perpendicular to this test pattern.

13. as claim 8,9,10, one of 11 described methods, wherein this set direction comprises the direction of level in this test pattern.

14. as claim 8,9,10, one of 11 described methods, wherein the set pattern of this test pattern is chequered with black and white striped.

15. method as claimed in claim 14, wherein when those sensors scan blackstreak, corresponding signal waveform is the low-light level district, when those sensors scan white stripes, corresponding signal waveform is a high luminance area, when those sensors scanned part blackstreak and part white stripes, its corresponding signal waveform brightness was between this high luminance area and low-light level district.

16. method as claimed in claim 8, the spacing of wherein calculating the sensor of these adjacent two sensing wafer end points is, translation is positioned at the sensor institute sensed signal waveform of adjacent two sensing wafer end points, till overlapping, calculate its translation distance, with the spacing of the sensor of obtaining these adjacent two sensing wafer end points.

17. method as claimed in claim 8, wherein this set direction comprises the direction that makes this contact-type image sensing device module and this test pattern be a set angle.

18. method as claimed in claim 17, wherein this set direction comprises the direction that makes this contact-type image sensing device module and this test pattern be one 45 degree angles.

19. a method of measuring the image sensing wafer skew comprises the following steps:

One contact-type image sensing device module is provided, and it comprises many sensing wafers that form a line, and each sensing wafer disposes a plurality of sensors;

One first test pattern is provided, and it has the alternate test section of horizontal stripe;

This contact-type image sensing device module relatively moves to this first test pattern with a specific direction, to scan;

Obtain the sensor sensed signal waveform that is positioned at adjacent two sensing wafer end points;

Calculate the vertical interval of the sensor of these adjacent two sensing wafer end points according to those signal waveforms;

One second test pattern is provided, and it has the alternate test section of oblique striped;

This second test pattern is scanned with this specific direction by this contact-type image sensing device module, this specific direction has a pitch angle with this oblique striped;

Obtain at least three sensor sensed signal waveforms that are positioned at adjacent two sensor wafer end points; And

According to this vertical interval, those at least three sensor sensed signal waveforms, and the level interval of the sensor of these adjacent two sensing wafer end points of this tilt angle calculation.

20. method as claimed in claim 19, wherein this pitch angle is 45 degree.

21. method as claimed in claim 19, wherein this first test pattern and this second test pattern are by the synthetic test pattern of light.

22. method as claimed in claim 21, wherein this first test pattern and this second test pattern are made up of the interference fringe that laser produced.

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