JPH06160054A - Image processing device - Google Patents

Abstract

PURPOSE:To correct the displacement of a specimen to a measuring reference position between two cameras, by forming image data with first and second cameras on the basis of voltage data per picture element of a specimen image existing in first and second measuring positions. CONSTITUTION:A specific part of a reference lead frame existing in a first measuring position is put as a linear edge 44 of an inner lead 42. A first reference position is indicated by a pointer 48a in a scale 46 attached on a slider. An MPU 28 drives an X-Y table 22 and moves the reference lead frame to a second measuring position when the first reference position is determined in sampling measurement. By the mechanical error of the X-Y table 22, the linear edge 44 of the inner lead 42 is biased by a distance D to right from a second measuring position. The MPU 28 finds the distance D by operating to store it in a memory 36. When a biased quantity is determined by this, the real width measurement of the inner lead is carried out.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image processing apparatus, and more specifically, a first example of an image of a sample based on voltage data for each pixel.
An image processing apparatus including first input means and second input means for generating image data of

[0002]

2. Description of the Related Art Conventionally, image processing technology has been used to measure, for example, the size of inner leads of a lead frame which is a sample. 2. Description of the Related Art Recently, image processing apparatuses that use a plurality of CCD cameras as input means have been adopted for the purpose of changing the image magnification for highly accurate measurement and increasing the speed of measurement work. In the case of an image processing apparatus having two input means for changing the image magnification, the designated portion of the inner lead is measured by the first camera having the same magnification. When it is desired to measure the portion more precisely, the same portion is measured with a second camera having a high magnification. In the measurement, dimensions and the like are usually measured using a specific position within the visual field of the camera as a measurement reference position. This measurement is performed by the computer system. A transport mechanism for moving the lead frame is provided in order to make the inner leads to be measured correspond between the first camera and the second camera. There is also an image processing apparatus of a type in which the inner lead is caught by the same lens and the optical path is switched via the switching means without moving the lead frame, thereby switching the first camera and the second camera.

[0003]

However, the above-described conventional image processing apparatus having a plurality of cameras has the following problems. The first camera and the second camera must ensure that the specific position of the inner lead to be inspected is aligned with the measurement reference position within the field of view. In the case of the first camera, an arbitrary position corresponding to the specific position of the lead frame can be set as the measurement reference position, but in the case of the second camera,
The measurement reference position must be a position corresponding to the measurement reference position of the first camera. However, no matter how precisely the transport mechanism is manufactured, the mechanical error cannot be reduced to zero. Therefore, when the lead frame is conveyed, a deviation occurs between the measurement reference position of the second camera and the specific position of the inner lead, which causes a decrease in measurement accuracy and a decrease in measurement reliability. is there. Therefore,
Although an image processing apparatus capable of finely adjusting the mounting position of the first camera and / or the second camera has been proposed, even if a fine adjustment mechanism is provided, vibration of the transport mechanism affects the fine adjustment mechanism. On the contrary, it became clear that it would cause a gap.

In the case of the optical path switching type image processing apparatus, it is possible to prevent the occurrence of the shift due to the transport mechanism and the fine adjustment mechanism.
If the mounting accuracy of the switching means (for example, a reflecting mirror) for switching the optical path is low, the optical axis to the second camera is deviated, and like the former case, between the measurement reference position of the second camera and the specific position of the inner lead. However, there is a problem in that the measurement system and the measurement reliability are deteriorated due to the deviation. Therefore, it is an object of the present invention to provide an image processing apparatus capable of correcting the displacement of the sample with respect to the measurement reference position between the first input means and the second input means.

[0005]

In order to solve the above problems, the present invention has the following constitution. That is, first, the first configuration includes first input means for generating first image data of the image of the sample at the first measurement position based on voltage data for each pixel, and the first input means. A second input means for generating a second image data based on the voltage data for each pixel of the image of the sample at the second measurement position whose position is fixed, and the sample from the first measurement position. A transport mechanism for moving to a second measurement position, a first storage means for storing the first image data, and a second storage means for storing the second image data, The position of the specific location of the reference sample in the field of view of the first input means when the reference sample is at the first measurement position is defined as the first reference position in the field of view of the first input means, and When the reference sample is moved to the second measurement position via the transport mechanism, The deviation amount between the position of the specific portion of the reference sample in the visual field of the second input means and the second reference position corresponding to the first reference position in the visual field of the second input means is stored in advance. And a third storage means for storing the physical data such as dimensions of a designated portion of the specimen based on the second image data, and a computing means for obtaining corrected physical data obtained by correcting the physical data with the deviation amount. And generating second image data of the sample through the second input means, storing the second image data in the second storage means, and performing the calculation based on the second image data. Control means for obtaining the corrected physical data of the sample via the means.

In the second configuration, the first input means for generating the first image data of the image of the sample at the measurement position based on the voltage data for each pixel, and the position for the first input means. A second input means for generating second image data based on voltage data for each pixel of the image of the sample at the measurement position, and the first input means for generating the image data. Switching means for switching by the second input means, first storage means for storing the first image data, second storage means for storing the second image data, and a reference The first when the sample is at the measurement position
The position of the specific portion of the reference sample in the visual field of the input means is set as the first reference position in the visual field of the first input means, and the second input means is used when the image data is switched via the switching means. For storing in advance the amount of deviation between the position of the specific portion of the reference sample in the field of view of the second reference position and the second reference position corresponding to the first reference position in the field of view of the second input means. And storage means for calculating physical data such as dimensions of a designated portion of the sample based on the second image data, and calculating corrected physical data obtained by correcting the physical data with the deviation amount. Second image data of the specimen is generated via the input means of the second storage means, the second image data is stored in the second storage means, and the specimen is calculated based on the second image data via the calculation means. And a control means for obtaining the corrected physical data of Characterized by comprising. Further, in both of the above-mentioned configurations, the arithmetic means obtains physical data such as a size of a designated portion of the specimen based on the first image data, and the control means has physical data based on the first image data and the correction physical You may make it compare with data.

[0007]

[Operation] The operation will be described. In the first configuration,
The control means obtains the physical data such as the dimensions of the designated portion of the sample based on the second image data, and obtains the corrected physical data obtained by correcting the physical data with the bias amount measured in advance. Even if a positional deviation of the sample with respect to the second reference position of the second input unit occurs due to a physical error, it is possible to obtain corrected physical data that corrects the positional deviation. Further, in the second configuration, the control means obtains physical data such as the dimensions of the designated portion of the sample based on the second image data, and the physical data is corrected by the pre-measured deviation amount. Therefore, even if the position shift of the sample with respect to the second reference position of the second input unit occurs due to the optical axis shift caused by the switching unit, it becomes possible to obtain the corrected physical data in which the shift is corrected. . Further, in both configurations, the calculation means obtains physical data such as the size of the designated portion of the sample based on the first image data, and the control means compares the physical data based on the first image data with the corrected physical data. With the configuration, it is possible to find the difference between the two data.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will now be described in detail with reference to the accompanying drawings. (First Embodiment) A first embodiment will be described with reference to FIGS. FIG. 1 is a block diagram of the image processing apparatus of the first embodiment, and FIG. 2 is an explanatory diagram showing its mechanical structure. In the first embodiment, an image processing apparatus that measures the lead width of the inner lead of the lead frame, which is an example of the sample, will be described as an example. Reference numeral 10 denotes a first CCD camera which is a first input means, and has a large number of CCD elements 16a for converting an image of the lead frame 14 located immediately below the first measurement position into voltage data for each pixel.
The first camera 10 generates first image data, which is a binary signal, based on the voltage data. The first camera 10 is firmly fixed to the fixing member 18. The position of the fixing member 18 is fixed.

Reference numeral 20 is a second CCD which is a second input means.
It is a camera and incorporates a large number of CCD elements 16b for converting the image of the lead frame 14 located immediately below the second measurement position into voltage data for each pixel. The second camera 20 generates second image data which is a binary signal based on the voltage data. The second camera 20 is also firmly fixed to the fixing member 18, and the position with respect to the first camera 10 is also fixed. Reference numeral 22 denotes an XY table which is an example of a transport mechanism, and the slider 24 can be moved (two-dimensional movement) in the XY directions within a horizontal plane by a known drive mechanism including a motor. The slider 24 can hold the lead frame 14 at a predetermined position on the upper surface. When the first camera 10 generates the first image data, the XY table 22 moves the slider 24 to move the lead frame 1.
4 is placed at the first measurement position (the position indicated by the solid line in FIG. 2). On the other hand, when the second camera 20 generates the second image data, the slider 24 is moved to move the lead frame 1.
4 is arranged at the second measurement position (the position indicated by the chain double-dashed line in FIG. 2).

Reference numeral 26 denotes a ROM in which an operating system of the microprocessor (MPU) 28, a control program of the image processing apparatus, control data and the like are stored in advance. Reference numeral 30 denotes a RAM, and the memory area is a first memory 32, a second memory 34, a third memory 36, ...
.. is divided into The first memory 32 stores the first image data generated by the first camera 10 as a first storage unit. The second memory 34 stores, as a second storage unit, the second image data generated by the second camera 20.

The third memory 36 stores the amount of deviation measured in advance. Here, the deviation amount will be described. The first is a standard lead frame that has a standard shape and size.
, The position of a specific portion (for example, a straight edge portion of the inner lead) of the reference lead frame within the field of view of the first camera 10 is set to the first camera 10.
The first reference position within the field of view. When the reference lead frame is moved to the second measurement position via the XY table 22, the position of the specific position of the reference lead frame in the visual field of the second camera 20 and the position of the second camera 20. The second corresponding to the first reference position in the field of view
The difference from the reference position of is the amount of deviation. The amount of deviation is the deviation length,
It can be represented by the number of pixels forming the image of the second camera 20 corresponding to the deviation amount. The deviation amount is obtained by sampling and measuring the reference lead frame prior to the actual measurement. If the deviation amount is known, RO
It may be stored in M26 as control data. In addition, the RAM 30 temporarily stores commands and data input by the operator, data processed by the MPU 28, and the like. An external memory such as an IC card can be used instead of the RAM 30 as the first storage means, the second storage means, and the third storage means.

The MPU 28 has a function as a calculation means and a control means. The MPU 28 serves as a calculation means, based on the first image data stored in the first memory 32, the width of the designated portion of the inner lead (an example of physical data).
Ask for. Further, the width of the designated portion of the inner lead is obtained based on the second image data stored in the second memory 34, and the width obtained based on the second image data is set to the third value.
The correction width (correction physical data) corrected by the deviation amount stored in the memory 36 of FIG.

The MPU 28 as control means generates first image data of the lead frame 14 via the first camera 10 and stores it in the first memory 32. Where M
The PU 28 obtains the width of the designated portion of the inner lead of the lead frame 14 using the arithmetic function. For example, when it is determined that the second camera 20 having a high magnification needs to perform highly accurate measurement on the obtained width, the MPU 28 drives the XY table 22 to move the lead frame 14 from the first measurement position to the first measurement position. Move to measurement position 2. Therefore, the second image data of the lead frame 14 is generated via the second camera 20 and stored in the second memory 34. When the second image data is obtained, the MPU 28 uses the arithmetic function,
The correction width of the designated portion of the inner lead is obtained from the second image data. The MPU 28 compares this corrected width with the width based on the first image data to determine whether or not the width of the designated portion is good. In addition, the MPU 28 controls the operation of each unit of the image processing apparatus according to the control program.

Reference numeral 38 is a keyboard for inputting commands and data to the MPU 28. In addition, the amount of deviation can be input via the keyboard 38. When it is desired to correct the deviation amount, it can be input from the keyboard 38. The input means is not limited to the keyboard 38.
A display 40 displays information processed by the MPU 28, data input from the keyboard 38, and the like. The display means is not limited to the display 40.

Next, the operation will be described with further reference to FIGS. 3 and 4. First, the operation of sampling measurement for obtaining the amount of deviation will be described. The first camera 1 is shown in FIG.
An image of 0 is shown. At this time, the reference lead frame is held on the slider 24 and is in the first measurement position. The specific portion of the reference lead frame is the straight edge 44 of the inner lead 42. Therefore, the first reference position is the position indicated by the pointer 48a on the scale 46 mounted on the slider 24. The MPU 28 stores this first reference position in the RAM 30 during sampling measurement. When the first reference position is determined, the MPU 28 makes X
-The Y table 22 is driven to move the reference lead frame 14 to the second measurement position.

FIG. 4 shows an image of the second camera 20.
At this time, the reference lead frame is in the second measurement position. The position of the scale 46 indicated by the pointer 48b is the second reference position corresponding to the first reference position in FIG. However, due to a mechanical error of the XY table 22, the straight edge 44 of the inner lead 42 is displaced rightward from the second reference position by the distance D. The MPU 28 calculates this distance D and stores it in the third memory 36 with the deviation amount = + D. This determines the amount of bias. When the deviation amount D is determined, the actual width of the inner lead is measured.

When highly accurate measurement by the second camera 20 is required, a specific portion of the inner lead of the lead frame 14 to be measured (corresponding to the straight edge 44 in FIG. 4).
Is always deviated by + D from the second reference position, the MPU 28 measures the width of the inner lead from the second reference position and then performs a calculation for subtracting the deviation amount D to obtain the correction width. This corrected width is compared with the width obtained based on the first image data, and if the difference is within a predetermined allowable range, it is determined that the width of the designated portion is good,
Prepare for the next measurement. On the other hand, if the difference is outside the allowable range, it is determined that the width of the designated portion is defective, the width is displayed on the display 40, and the operator is notified.

(Second Embodiment) A second embodiment will be described with reference to FIG. The same components as those in the first embodiment are designated by the same reference numerals as those in the first embodiment, and the description thereof will be omitted. The image processing apparatus of the second embodiment is an optical path switching type image processing apparatus. In FIG. 5, 70a and 70b are optical path tubes. A lens 72 is attached to the lower end of the optical path tube 70a, and the upper end is connected to the first camera 10. on the other hand,
The optical path tube 70b is formed in an L shape, and the lower end is the optical path tube 70a.
The second camera 20 is connected to the second camera 20 at the upper end.

Reference numeral 74 denotes a mirror shutter which is an example of a switching means, and is provided in the optical path tube 70a at a portion communicating with the optical path tube 70b. Mirror shutter 74
Is rotatable about the shaft 76 as shown by an arrow X. When the mirror shutter 74 is at the position shown by the solid line in FIG. 5, the right side surface is formed as a reflecting surface, and the optical path can be turned 90 degrees to the right. As a result, lens 7
The light passing through 2 can be sent to the second camera 20. On the other hand, when the mirror shutter 74 is located at the position shown by the chain double-dashed line in FIG.
It is possible to send to. That is, in the second embodiment, a mirror shutter 74 is provided instead of the XY table 22 of the first embodiment.

Reference numeral 80 denotes a mirror shutter drive section, which comprises a rotary actuator including a motor, a solenoid, and the like.
The mirror shutter 74 is rotated as shown by arrow X.
Reference numeral 82 denotes a fixed mirror, which is used for the light path tube 70a to the light path tube 70
The light bent to b is sent to the second camera 20 on the optical path 78b. Therefore, in the second embodiment, the mirror shutter 74 is not moved without moving the lead frame 14, which is the sample.
By rotating the first camera 10 and the second camera 2
The measurement at 0 can be switched.

In the second embodiment, the optical path 78b (optical axis) to the second camera 20 may deviate from the predetermined optical path due to, for example, mechanical error or mounting error of the mirror shutter 74 or the fixed shutter 74. As a result, the second camera 20
There may be a deviation between the second reference position and the specific position of the lead frame 14 (for example, a straight edge of the inner lead). Even in this case, the corrected physical data can be obtained by previously obtaining the deviation amount D as in the first embodiment. Although various preferred embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments. For example, even when the number of input means is two or more, two input means of them will be described. Needless to say, many modifications can be made without departing from the spirit of the invention, such as adopting the present invention.

[0022]

When the image processing apparatus according to the present invention is used,
First, in the configuration of claim 1, the control means obtains physical data such as the size of the designated portion of the sample based on the second image data, and the corrected physical data is obtained by correcting the physical data with the bias amount measured in advance. Therefore, even if the displacement of the sample with respect to the second reference position of the second input unit occurs due to the mechanical error of the transport mechanism, it is possible to obtain the corrected physical data in which the displacement is corrected. Further, in the configuration of claim 3, the control means obtains the physical data such as the size of the designated portion of the sample based on the second image data, and the physical data is corrected by the pre-measured deviation amount. Since the data is obtained, even if the position shift of the sample with respect to the second reference position of the second input unit occurs due to the optical axis shift caused by the switching unit, it is possible to obtain the corrected physical data that corrects the shift. Therefore, the deviation of the sample with respect to the measurement reference position between the first input means and the second input means can be reliably corrected, and the measurement accuracy and the measurement reliability can be improved.
Further, in the configurations of claims 2 and 4, the arithmetic means is the first
When the physical data such as the size of the designated portion of the sample is obtained based on the image data of 1. and the control means is configured to compare the physical data based on the first image data and the corrected physical data, the difference between the two data is obtained. It is possible to achieve a remarkable effect.

[Brief description of drawings]

FIG. 1 is a block diagram showing a first embodiment of an image processing apparatus according to the present invention.

FIG. 2 is an explanatory view showing a mechanical configuration of the first embodiment.

FIG. 3 shows a first example at the time of sampling measurement in the first embodiment.
Explanatory drawing showing an image of the camera of FIG.

FIG. 4 shows a second example of sampling measurement in the first example.
Explanatory drawing showing an image of the camera of FIG.

FIG. 5 is an explanatory diagram showing a mechanical configuration of an image processing apparatus according to a second embodiment.

[Explanation of symbols]

 10 First Camera 14 Lead Frame 20 Second Camera 22 XY Table 28 MPU 32 First Memory 34 Second Memory 36 Third Memory 42 Inner Lead 44 Straight Edge 74 Mirror Shutter 80 Mirror Shutter Drive Unit 82 Fixed mirror

Claims (4)

[Claims] 1. A first image data generating device for generating an image of a sample at a first measurement position based on voltage data for each pixel.
Input means and the position with respect to the first input means are fixed, and the image of the sample at the second measurement position is set to the second based on the voltage data for each pixel.
Second input means for generating the image data of, a transport mechanism for moving the sample from the first measurement position to the second measurement position, and a first storage unit for storing the first image data. Storage means, second storage means for storing the second image data, and specification of the reference sample in the visual field of the first input means when the reference sample is at the first measurement position The position of the location is set as a first reference position within the field of view of the first input means, and the field of view of the second input means when the reference sample is moved to the second measurement position via the transport mechanism. A third amount for pre-storing the amount of deviation between the position of the specific portion of the reference sample in the inside and the second reference position corresponding to the first reference position in the field of view of the second input means. Storage means and designation of specimen based on the second image data A second image data of the sample is generated through a calculation unit that obtains physical data such as a size of a minute and obtains corrected physical data obtained by correcting the physical data with the deviation amount; Control means for storing the second image data in the second storage means and for obtaining the corrected physical data of the sample through the computing means based on the second image data. Image processing device. 2. The calculation means obtains physical data such as a size of a designated portion of a sample based on the first image data, and the control means calculates the physical data based on the first image data and the corrected physical data. The image processing device according to claim 1, wherein 3. A first input means for generating first image data based on voltage data for each pixel of an image of a sample at a measurement position, and a position relative to the first input means is fixed. Second input means for generating second image data based on voltage data for each pixel of the image of the sample at the measurement position, and generation of the image data by the first input means and the second input means. A switching unit for switching the first image data, a first storage unit for storing the first image data, a second storage unit for storing the second image data, and a reference sample at the measurement position. The position of the specific location of the reference sample in the visual field of the first input means when
The first reference position in the visual field of the input means, and the position of the specific portion of the reference sample in the visual field of the second input means when the image data is switched via the switching means, and the second input. Third storage means for storing in advance the amount of deviation from the second reference position corresponding to the first reference position within the field of view of the means, and designation of the specimen based on the second image data. Calculating physical data such as the size of the part, calculating the corrected physical data by correcting the physical data with the deviation amount, and generating the second image data of the sample through the second input means, Control means for storing the second image data in the second storage means and for obtaining the corrected physical data of the sample through the computing means based on the second image data. Image processing device. 4. The calculation means obtains physical data such as a size of a designated portion of a sample based on the first image data, and the control means calculates the physical data based on the first image data and the corrected physical data. The image processing device according to claim 3, wherein