JPH04241476A - Lighting apparatus - Google Patents

Abstract

PURPOSE:To provide an appropriate lighting apparatus for using in inspection of a bonding wire such as hybrid ICs with various directions and shapes of the bonding wire. CONSTITUTION:A plurality of LED lamps 14aa to 14ah, 14ba to 14bh and 14ca to 14ch constitute three ring LED arrays 15a to 15c, and the LED arrays 15a to 15c are placed concentrically while they have different lighting angles respectively against an object to be illuminated. Then light emission of the respective LED lamps 14ah to 14ch is selectively controlled according to the object to be illuminated.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lighting device used in a wire inspection device for a hybrid IC.

0002

[Prior Art] FIGS. 8 and 9 are, for example, Japanese Patent Application Laid-Open No. 1-2516
These are a configuration diagram and a plan view showing a conventional illumination device shown in Publication No. 30. In the figure, 1 is a light source, 2 is a large diameter main optical fiber connected to this light source 1, and 3 is this main optical fiber 2. 4a to 4d are branched optical fibers branched by the shutter unit 3, 5 is a light guide that guides the light from the branched optical fibers 4a to 4d, and 6 is a shutter unit that directs the light from the light guide 5 inward. The horizontal illumination devices 7a to 7d are illumination areas into which light is introduced by branched optical fibers 4a to 4d and divided into four equal areas.

Reference numeral 8 denotes a lead frame, 9 an IC chip bonded on the lead frame 8, 10 a bonding wire to be inspected that connects the lead frame 8 and the IC chip 9, and 11 a bonding wire 1.
0 is an ITV camera that images 12 is a shutter unit 3
This is an image processing device that controls the ITV camera 11 and processes image signals from the ITV camera 11.

Next, the operation will be explained. The branched optical fibers 4a to 4d are connected around the light guide 5 at positions dividing it into four equal parts, thereby dividing the lighting fixture 6 into four equal illumination areas 7a to 7d. The image processing device 12 outputs a control signal to block the light from the diffuser closest to the location where the bonding wire 10 is being inspected, and this control signal is input to the shutter unit 3. On the other hand, light from a light source 1 is guided by a main optical fiber 2, and a shutter unit 3 independently controls light transmission and light blocking of each of the branch optical fibers 4a to 4d.

For example, when inspecting the bonding wire 8 included in the illumination area 7b, the shutter unit 3 blocks the light to the branched optical fiber 4b for illuminating this illumination area 7b, and the other branched optical fibers 4a, 4c are ，
Transmits light to 4d. This makes it possible to suppress the light from the branched optical fiber 4b that is generated and reflected from the edge portions of the IC chip 9 and the lead frame 8 and from the die bonding paste, which would interfere with the inspection of the bonding wire 10. Further, the reflected light necessary for inspection can be sufficiently obtained by the light from the branched optical fibers 4a, 4c, and 4d.

[0006] As a result of the above, the reflected light is transmitted to the ITV camera 1.
1, the image is processed by the image processing device 12, and wire inspection is performed.

[0007]

[Problems to be Solved by the Invention] Since the conventional lighting device is constructed as follows, the bonding wire 10
In the case of hybrid ICs in which multiple IC chips and other components are mounted on the same substrate, the directions and heights of the substrates and IC chips are diverse, and the colors, shapes, surface conditions, and sizes of the substrates and IC chips are also diverse. If the lighting is harsh, unnecessary shadows will be created by other IC chips and other components, and the wires being inspected will not be exposed to light. In addition, because the color, shape, surface condition, etc. are complex, the influence of other parts of each wire differs when inspecting each wire, so it may be difficult to simply dim the light from only the side of the wire being inspected. Not enough. Since the lighting equipment surrounds the IC to be inspected, in the case of a large board, the lighting equipment becomes larger accordingly. There were problems such as the large size of the light source and the inability to provide the best illumination for each wire.

The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide an illumination device that can be used for wire inspection of hybrid ICs in which bonding wires have various directions.

[0009]

[Means for Solving the Problems] A lighting device according to the present invention is configured such that a ring light formed by arranging a plurality of light emitting elements can be partially lit, and a plurality of the ring lights are arranged concentrically, The ring lights are arranged at different angles relative to the inspection object, and are provided with lighting control means for controlling the lighting of the plurality of ring lights.

0010

[Operation] The ring illumination according to the present invention performs illumination according to the shape of each wire by controlling the light emission of each light emitting element by the illumination control means.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

In FIGS. 1 and 2, 13 is a substrate, 9 is an IC chip mounted on the substrate 13, and 10 is a connection between the substrate 13 and the I
The bonding wires 14aa to 14ch that are the objects of inspection that connect the C chip 9 are LEs as light emitting elements.
D lamps, 15a to 15c are LE arranged concentrically
D lamp 14aa~14ah, 14ba~14bh, 1
An LED array 15a is an annular light emitting element array consisting of 4ca to 14ch, and 16 is an LED array 15a with different illumination angles relative to the substrate 13 which is the illumination target.
15c is attached, and has a central hole 16a. 1
8 is an illuminator consisting of a substrate 16, LED arrays 15a to 15c, etc.; 11 is an ITV camera that captures an image of the bonding wire 10 on the substrate 13 through the central hole 16a;
2 is an image processing device that processes image signals from the ITV camera 11; 17 is an image processing device that inputs a lighting pattern from the image processing device 12;
This is a lighting control power source that selectively turns on channels. In addition,
The image processing device 12 and the lighting control power source 17 constitute a lighting control means.

Next, the operation will be explained.

The wire-bonded substrate 13 is positioned within the field of view of the ITV camera 11. Next, I
Bonding wire 10 in the field of view of TV camera 11
A preset lighting pattern is output from the image processing device 12 to the lighting control power source 17 according to the shape of the lighting pattern, and the LED lamps 14aa to 14ch of the illuminator 18 are turned on according to the lighting pattern. . The bonding wire 10 illuminated by the illuminator 18 is imaged by the ITV camera 11, and the image signal from the ITV camera 11 is processed by the image processing device 12, thereby recognizing and determining the bonding wire 10.

Note that in the above embodiment, the LED lamp 14
Although a method for turning on/off channels aa~14 has been shown, each LED lamp 14a~14ch is controlled by the image processing device 12.
Input the brightness code of each LED into the lighting control power supply 17.
The brightness may be controlled by controlling the current flowing through the lamps 14aa to 14ch.

Furthermore, in the above embodiment, the LED array 15
Although LED arrays a to 15c are arranged on a flat surface, each LED array may be arranged on a spherical substrate 16 as shown in FIG. Further, as shown in FIG. 4, the LED arrays 15a to 15c may be arranged on three substrates 16 having different heights. With the configurations shown in FIGS. 3 and 4, illumination from a higher angle becomes possible.

[0017] In addition, LED lamps are not only available in a single color;
LED lamps of a plurality of colors emitting different colors may be arranged side by side, or a multicolor LED lamp including LED chips emitting different colors within the same LED lamp may be used. In that case, by changing the color and brightness of the illumination depending on the color of the IC chip or substrate, it is possible to obtain an image that is easier to recognize.

Furthermore, instead of the LED lamp, it may be configured using LED chip parts, lenses, prisms, etc., and further miniaturization is possible.

Furthermore, in the above embodiment, each row of LED lamps has 8 LED lamps.
Although the case where LED lamps 14 are arranged in three rows is shown, the number of rows and the number of LED lamps may be determined depending on the object to be illuminated. For example, as shown in FIG.
If there is no problem in recognition if the block is divided into blocks, three LED lamps 14 of each block 18 may be serially connected as shown in FIG.

[0020]Also, in the above embodiment, the illumination is only ring illumination by the LED arrays 15a to 15c, but
As shown in FIG. 7, the ring illumination and epi-illumination controlled by the epi-illumination control unit 19 may be combined to control the brightness of light from each illumination direction, thereby creating images that are easier to recognize. Obtainable.

[0021] Furthermore, by using an LED lamp,
It has advantages such as low power consumption, long life, small size, easy control of light intensity because current can be controlled, and pulse lighting possible due to high-speed response.

Further, in the above embodiment, the case where a bonding wire is used as the object to be illuminated has been described, but other objects such as IC leads may be used, and the same effects as in the above embodiment can be obtained.

[0023]

[Effects of the Invention] As described above, according to the present invention, the illumination conditions of the illuminator can be set in detail according to the shape of each bonding wire, so that recognition of each bonding wire is easy. This has the effect of making it easier.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing a lighting device according to an embodiment of the present invention.

FIG. 2 is a configuration diagram showing a lighting device according to an embodiment of the present invention.

FIG. 3 is a configuration diagram of a lighting device according to another embodiment of the present invention.

FIG. 4 is a configuration diagram of a lighting device according to another embodiment of the present invention.

FIG. 5 is a plan view of a lighting device according to another embodiment of the invention.

FIG. 6 is a circuit configuration diagram of main parts of a lighting device according to another embodiment of the present invention.

FIG. 7 is a configuration diagram of a lighting device according to another embodiment of the present invention.

FIG. 8 is a configuration diagram of a conventional lighting device.

FIG. 9 is a plan view of a conventional lighting device.

[Explanation of symbols]

12, 17 Lighting control means 14 Light emitting element 15 Light emitting element array 16 Illuminator

Claims (1)

[Claims] Claim 1: A plurality of light emitting element arrays in which a plurality of light emitting elements are arranged in a ring shape are arranged concentrically, and each light emitting element array is arranged so that the illumination angle is different with respect to the illumination target. and lighting control means for selectively controlling the plurality of light emitting elements in an arbitrary light emission pattern.