JPH05167835A - Magnification varying method in image input device - Google Patents

Abstract

PURPOSE:To save a cost and handling time by enabling a conventional image processing part to be used as it is by using a CCD line sensor with high resolution in a magnification varying method for an optical device used as an image input device and equipped with the CCD line sensor. CONSTITUTION:This device is the image input device provided with an image processing part which obtains image data by scanning a reflected light of a beam of light by the optical device and A/D-converting an electrical signal from the optical device, and the magnification of the optical device 2a can be varied by using a CCD line sensor 3a with high resolution in which the number of elements of the CCD line sensor is multiplied by prescribed number, using the image processing part 5 as it is, selecting the image data obtained from a scan object arbitrarily by a fetch step switching part 6 interposed between the CCD line sensor 3a with high resolution and the memory of the image processing part 5, and fetching it in the memory of the image processing part 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of varying the magnification of an optical device used as an image input device such as a mounting inspection device for a printed circuit board and having a CCD line sensor.

[0002]

2. Description of the Related Art Conventionally, in an image input device, as shown in FIG. 5, a CCD line sensor 3 is used as an optical device 2 for scanning reflected light from an object to be scanned (for example, a mounted printed circuit board), and a resolution is set. In order to increase the distance, the method of changing the focal length by changing the lens 4 and the CCD line sensor 3
There was a method to change to the one with a large number of elements.

[0003]

However, the method of replacing the lens 4 described above requires labor and adjustment work for replacement, and costs such as attaching a replacement lens to the image input device or making it an option. It will be up.

Further, as shown in FIGS. 6 to 8, a CCD line sensor 3 having, for example, 2048 elements is used, and this is doubled as shown in FIG. When the resolution is increased by replacing the CCD line sensor 3a with the image processing section 5a, the image processing section 5 shown in FIG. 8 must be provided with another substrate for high resolution processing for the CCD line sensor 3a.

The image processing section 5 A / D-converts the electric signal of the CCD line sensor 3 via a video amplifier to write digital data of 64 gradations in a memory. In this case, the CCD line sensor B and the memory B are provided in FIG. 8 because the optical device 2 moves in two directions of XY and scans.

In this way, the optical device 2 has a high resolution.
There was a drawback in that changing the magnification of was troublesome and costly.

The present invention has been made in view of the above problems, and even if a high-resolution CCD line sensor is used, the conventional image processing unit can be used as it is to reduce the cost and save the labor. An object of the present invention is to provide a method for varying the magnification of an optical device.

[0008]

The object of the present invention to solve the above-mentioned problems and achieve the above-mentioned object is to provide a CCD line sensor and a lens with which reflected light of a light beam emitted from a light source to a scanning object at a predetermined angle is reflected. An image input device having an image processing unit that scans with an optical device equipped with a camera and A / D-converts an electrical signal from the optical device to obtain image data. A high resolution CCD line sensor that has a predetermined magnification is used, and the image processing unit is left as it is, and a capture step switching unit interposed between the high resolution CCD line sensor and the memory of the image processing unit is used to scan the object to be scanned. It consists in arbitrarily selecting the obtained image data into the memory of the image processing unit and changing the magnification of the optical device.

[0009]

According to the variable magnification method of the present invention, the CCD line sensor of the image input device is replaced with a high resolution one,
In addition, only by providing the capturing step switching unit, the electric signal of any element of the high resolution CCD line sensor is stored in the memory while leaving the image processing unit as it is.
/ D conversion and writing. As a result, the resolution of the image input device is improved, and the image data in an arbitrary range in the main scanning direction can be captured by arbitrarily changing the memory capture start position.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of the present invention. In the figure, reference numeral 3a indicates a CC having 4096 elements.
D line sensor, 6 capture step switching unit, 7 CCD clock generating unit, 8 memory control, 9
Indicate the capture step switching devices, respectively, and the portions corresponding to the conventional ones are designated by the same reference numerals.

In the present invention, as an embodiment, the image processing unit 5 in the case of using the CCD line sensor 3 having the conventional number of 2048 elements is used as it is. In order to double the resolution, for example, a high resolution CCD line sensor 3a having 4096 elements is provided in the optical device 2a as shown in FIG.

A CCD clock generator 7, a memory controller 8, and a capture step switching unit 6 having a capture step switching device 9 are provided. The CCD
The clock generator 7 doubles the clock frequency to enable scanning of the high resolution CCD line sensor 3a,
64 in the memory of the image processing unit 5 by the memory control 8.
Controls writing of gradation digital data.

According to the image input device having such a configuration,
As shown in FIG. 4, L ₁ which is the main scanning range of the scanning object ₁
High-resolution CCD of the optical device 2a
It is scanned by the line sensor 3a and is converted into digital data of 64 gradations by the A / D conversion unit via the video amplifier of the image processing unit 5. Then, the capturing step switching device 9
Then, when it is set so that every other image data is fetched, every other element 1 of the high resolution CCD line sensor 3a shown in FIG.
2048 64 gradation digital data of 0, 11, ... 14, ... are fetched and written in the memory.

When scanning by the optical device 2a is performed in two directions, the CCD line sensor B is used and written in the memory B in the same manner as described above. afterwards,
The presence / absence of a component or the like of the scan target 1 is determined via the value calculation unit or the like.

When the fetching step switching unit 9 is set to continuously fetch image data, the elements 15, 16 of the high resolution CCD line sensor 3a are controlled by the memory control 8 as shown in FIG. ，
2048 which is continuous with 17, 18, 19, ... 20, 21 ...
The individual 64 gradation digital data are fetched and written in the memory.

This is the main scanning range L as shown in FIG.
_This means that the image data in the range of L ₂ which is half of ₁ has been read. Of course, the resolution is a CCD with 2048 elements
It is twice as much as when the line center 3 is used. Furthermore,
If the start position of the main scanning range L ₁ to be written in the memory of the image processing unit 5 is changed by the memory control 8, for example, it can be read from 2048 64 gradation digital data after the element 21 shown in FIG. , The image data in the range of L ₃ shown in FIG.

In this way, the range of capturing image data can be arbitrarily changed within the main scanning range L ₁ . Then, the optical device 2a is moved at a constant speed in the sub-scanning direction of two directions of XY or one direction, the image data of the scanning object 1 is taken in, and the image data is delivered to the subsequent processing system.

In the above embodiment, C having 4096 elements is used.
The case where the CD line sensor is used and the resolution is doubled by using the image processing unit of the conventional low-resolution processing system as it is has been described, but the present invention is not limited to this and the CCD line having an arbitrary number of elements can be used. Equipped with a high resolution CCD line sensor with a multiple number of elements for the sensor, the image capture step switching unit captures image data at every required step, or continuously captures image data from an appropriate location, The resolution can be varied according to the magnification of the high resolution CCD line sensor.

[0019]

As described above, the method of varying the magnification in the image input apparatus of the present invention uses the high resolution CCD line sensor in which the number of CCD line sensor elements is set to a predetermined number, and the image processing unit is left as it is. The high resolution C
A capture step switching unit interposed between the CD line sensor and the memory of the image processing unit arbitrarily selects image data obtained from the scanning object and captures it in the memory of the image processing unit. Since the magnification is variable, it is not necessary to change the image processing unit even if the CCD line sensor is changed to a high resolution one, which reduces the cost.

Further, since the capturing range of the image data within the main scanning range can be arbitrarily changed by setting the capturing step switching section, it is possible to easily cope with the case where the scanning object is different in size and the lens of the optical device. It is possible to obtain high-resolution image data without the need to replace or adjust the focal length.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention.

FIG. 2 is a front view of a high resolution CCD line sensor.

FIG. 3 is a front view of a high resolution CCD line sensor of the same.

FIG. 4 is an explanatory diagram showing a usage state of the optical device.

FIG. 5 is an explanatory diagram showing a usage state of an optical device in a conventional example.

FIG. 6 is a front view of a CCD line sensor in a conventional example.

FIG. 7 is a front view of a high resolution CCD line sensor.

FIG. 8 is a block diagram of an optical device and an image processing unit in a conventional example.

[Explanation of symbols]

3a CCD line sensor with 4096 elements, 4
Lens, 5 image processing unit, 6 capture step switching unit, 7 CCD clock generating unit, 8 memory control, 9 capture step switching device.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display location G01N 21/88 F 8304-2J G06F 15/64 325 B 8840-5L

Claims (1)

[Claims] 1. An optical device equipped with a camera composed of a CCD line sensor and a lens scans the reflected light of a light beam emitted from a light source to a scanning object at a predetermined angle, and an electric signal from the optical device is converted into an A / D signal. An image input device having an image processing unit for converting to obtain image data, wherein a high resolution CCD line sensor in which the number of elements of the CCD line sensor is set to a predetermined number is used, and the image processing unit is left unchanged. The image data obtained from the scanning object is arbitrarily selected by the capture step switching unit interposed between the resolution CCD line sensor and the memory of the image processing unit and captured in the memory of the image processing unit, and the optical device A method for changing the magnification in an image input device, characterized in that the magnification is changed.