TWI448730B - Even lighting scanning type visual system - Google Patents

Description

Uniformly illuminated scanning vision system

The present invention relates to a scanning vision system, and more particularly to a scanning vision system that uniformly illuminates.

The conventional fixed visual lighting system is mostly implemented by fixed image capturing and lighting positions, and according to the form of the light source, it can be divided into dark field lighting and bright field lighting, and the two types of lighting. The image contrast is in the opposite state. As shown in Fig. 1, the fixed visual lighting system 1 has a dark field effect of dark field lighting since the angle of installation of the image capturing device 10 and the lighting device 11 is close to 45°. On the other hand, in the fixed visual lighting system 2 shown in FIG. 2, since the installation angle of the image capturing device 20 and the lighting device 21 is close to 90°, a bright field effect of bright field lighting is generated.

In the current scanning vision system, since the scanner rotates the built-in lens by the electro-rotating element, the scanning angle changes during the scanning process, and the bright field effect and the dark field effect are mixed. As shown in FIG. 3, the scanner 30 and the lighting device 31 of the scanning vision system 3 are disposed above the illumination area 32. When the scanner 30 is guided by the rotary galvanometer, the laser and the vision pair are irradiated. When the image capturing point A of 32 is engraved and imaged, a dark field effect is generated, and when the scanner 30 guides the laser and the mirror to engrave the image point B of the irradiation area 32 by rotating the galvanometer. When the image is taken, a bright field effect is produced. However, each of the image capturing points on the illumination area 32 does not have equal brightness when scanning is taken using conventional techniques.

The disadvantage of the above operation is that when the dark field effect and the bright field effect are mixed, the optimal uniformity on the illumination area 32 can only be close to 70%, so that the conventional scanning vision system 3 cannot obtain better image contrast. It is easy to cause misjudgment of subsequent image capture software and even lead to positioning error. In the published patent documents, such as Taiwan Patent No. I290223, I282855, 201017060, and U.S. Patent Nos. 5,822,053, 5,825, 495, all of which are directed to conventional fixed-type visual lighting systems to form a light source adjustable type. However, it does not actually solve the problem that the dark field effect and the bright field effect are mixed during the scanning process of the current scanning vision system.

In view of the various deficiencies of the prior art, one of the primary objects of the present invention is to provide a technique that avoids the effects of dark field effects and bright field effects in a scanning vision system.

To achieve the above and other objects, the present invention provides a scanning system for uniform illumination, comprising a scanner disposed above an illumination area and imaging the illumination area by rotating the lens; The light-emitting device is disposed on at least two sides of the illumination area for projecting a light source toward the illumination area, so that each image capturing point obtained by the scanner has equal brightness.

In one embodiment, the illumination area is square, and the lighting device is provided with four strip-shaped lighting units to be placed on the four sides of the illumination surface, or has two strips. The lighting unit is disposed on two opposite sides of the illumination surface.

In another embodiment, the illumination surface is square, and the light-emitting device is provided with two elongated light-emitting units for being disposed on two adjacent sides of the illumination surface.

Compared with the prior art, the lighting unit of the scanning vision system of the present invention is respectively disposed on at least two sides around the irradiation surface, and the lighting unit can project the lateral light source toward the irradiation area to make each take The image points have equal brightness. Therefore, when the scanner performs laser engraving and image capturing on the illumination area by rotating the lens, the problems of bright field effect and dark field effect mixing can be greatly reduced, thereby avoiding subsequent positioning errors. .

The embodiments of the present invention are described below by way of specific embodiments, and those skilled in the art can readily appreciate the other advantages and advantages of the present invention. Of course, the invention may be embodied or applied by other different embodiments.

Please refer to FIG. 4 to FIG. 8 for further understanding of the uniform illumination scanning vision system of the present invention, wherein FIG. 4 is a schematic diagram of the overall configuration of the uniform illumination scanning vision system of the present invention. Figure 5 is a schematic view of one of the polishing devices of the uniform illumination scanning vision system of the present invention, and Figure 6 is a schematic view of another polishing device of the uniform illumination scanning vision system of the present invention, Figure 7 It is a schematic diagram of another polishing device of the uniform illumination scanning vision system of the present invention, and FIG. 8 is a corresponding relationship diagram of the lighting device and the illumination surface of the uniform illumination scanning vision system of the present invention.

As shown in the figure, the uniform illumination scanning vision system 4 of the present invention comprises a scanner 40 and a lighting device 41. In this embodiment, the lighting device 41 is provided with at least two groups of lighting units, and is polished. The unit has a plurality of light emitting diodes capable of laterally projecting light sources. Further, the irradiation area of the present embodiment is a plane (hereinafter referred to as an irradiation surface 5), and the lighting unit projects a light source to the irradiation surface 5.

The scanner 40 is disposed above the irradiation surface 5 for illuminating the surface 5 for image taking. In this embodiment, the illumination surface 5 may be a square platform having an area greater than 180*180 mm ² , and the scanner 40 is compatible with the laser unit 42 and the detection unit 43 (for example, a CCD) having an output wavelength of 100 nm to 100,000 nm. And the visual imaging unit 44 (for example, an imaging lens) is matched with each other, thereby guiding the laser generated by the laser unit 42 to engrave the illumination surface 5, and guiding the vision imaging to the visual imaging unit 44 and the detection unit. 43 to take the image. Furthermore, the scanner 40 can be provided with an electro-rotation element for engraving and imaging the illumination surface 5 by rotating the lens, and the scanner 40 faces the illumination surface 5 for the laser and the imaging end face. A focusing lens 45 is mounted.

The lighting device 41 is disposed on at least two sides of the irradiation surface 5 to project a light source toward the irradiation surface 5 so that each of the image capturing points on the irradiation surface 5 has equal brightness. In this embodiment, the illumination surface 5 is square, and the lighting device 41 is provided with four strip-shaped lighting units 410, 411, 412, 413; secondly, each of the lighting units 410, 411, 412, 413 One or a plurality of light sources 414 may be disposed, and the light source 414 may have a light emitting surface 415 perpendicular to the illumination surface 5; specifically, the light-emitting units 410, 411, 412, and 413 may be placed in the illumination. The four sides of the face 5, and the light-emitting face 415 of the light source 414 on the light-emitting units 410, 411, 412, 413 can be perpendicular to the illuminated face 5, as shown in Figures 4 and 5. In addition, the lighting device 41 may be formed by providing the strip-shaped lighting units 411 and 413 provided on the opposite sides of the irradiation surface 5 or on the other two opposite sides of the irradiation surface 5. The lighting units 410 and 412 are configured as shown in FIG.

Specifically, in the embodiment of FIG. 5 or FIG. 7, the illumination unit 5 and the lighting unit of the lighting device 41 can satisfy the geometric formula: D=L-2(d2+d3)tanθ. Referring to FIG. 8 together, in the above formula, D is the width of the illumination surface 5, L is the horizontal distance between the light-emitting units 411 (410) and 413 (412) on the opposite sides of the illumination surface 5, and d2 is the illumination. The bottom of the units 411 (410), 413 (412) is the height of the illumination surface 5, d3 is the height of the light-emitting units 411 (410), 413 (412) itself, and θ is the lighting unit 411 (410), 413 ( The illuminating angle of 412), and the d1 shown in the figure corresponds to the horizontal distance of the illuminating surface of the lighting units 411 (410) and 413 (412) from the illuminating surface 5 corresponding to the illuminating angle θ. In other words, the range in which the lighting device 41 surrounds may be 1.5 to 2 times, for example, 1.7 times the irradiation surface 5. However, the setting angles of the lighting units 411 (410) and 413 (412) may also have a certain tolerance range, that is, the setting angles of the light-emitting surfaces of the lighting units 411 (410) and 413 (412) with respect to the irradiation surface 5 may be Between 80° and 100° (90° ± 10°).

In another embodiment, the two sets of strip-shaped lighting units of the lighting device 41 may be disposed on two adjacent sides of the illumination surface 5, as shown in FIG. 6, only the lighting units 411, 412 are disposed on Two adjacent sides of the illuminated surface 5 are illuminated. The angles of the light-emitting surfaces of the light-emitting units 411 and 412 with respect to the illumination surface 5 may have a certain tolerance range, that is, between 80° and 100° (90°±10°). It should be noted that compared with Fig. 5, the embodiment of Figs. 6 and 7 causes a decrease in brightness and a decrease in the illumination range, but does not affect that each image point on the illumination surface 5 should be equal. Brightness.

Actual test, as shown in Figure 4, the four-sided surrounding lighting unit and the traditional two-sided square light source adjustable type (not shown), it is found that if the area of the illuminated surface 5 is 400*400mm ² , this The uniformity simulation result of the invention is at least 97.3%, and the uniformity simulation result of the conventional double-layer square light source adjustable state is at most 65.6%. Therefore, the present invention can significantly reduce the bright field effect and the dark field. The effect blends with the defects.

In summary, the uniform illumination scanning vision system of the present invention has the lighting unit of the lighting device disposed on at least two sides of the illumination surface, and the lighting units are capable of facing the illumination surface. Projecting the lateral light source so that each image capturing point on the illuminated surface has equal brightness, so that when the scanner performs image capturing, the probability of mixing the bright field effect and the dark field effect is greatly reduced, thereby improving the subsequent Positioning accuracy.

However, the above-described embodiments are merely illustrative of the principles and effects of the invention and are not intended to limit the invention. Modifications and variations of the above-described embodiments can be made by those skilled in the art without departing from the spirit and scope of the invention. Therefore, the scope of protection of the present invention should be as set forth in the scope of the claims described below.

1, 2. . . Fixed visual lighting system

10, 20. . . Image capture device

11, 21. . . Lighting device

3. . . Scanning vision system

30. . . scanner

31. . . Lighting device

32. . . Irradiated area

4. . . Uniformly illuminated scanning vision system

40. . . scanner

41. . . Lighting device

410, 411, 412, 413. . . Lighting unit

414. . . light source

415. . . Luminous surface

42. . . Laser unit

43. . . Detection unit

44. . . Visual imaging unit

45. . . Focusing lens

5. . . Irradiated surface

Figure 1 is a schematic diagram of one of the existing fixed visual lighting systems;

Figure 2 is a schematic diagram of another configuration of the existing fixed visual lighting system;

Figure 3 is a schematic diagram of the configuration of the existing scanning vision system;

Figure 4 is a schematic view showing the overall configuration of the uniform illumination scanning vision system of the present invention;

Figure 5 is a schematic view of a light-emitting device of the uniform illumination scanning vision system of the present invention;

Figure 6 is a schematic view of another light-emitting device of the uniformly illuminated scanning vision system of the present invention;

Figure 7 is a schematic view of another polishing device of the uniformly illuminated scanning vision system of the present invention;

Figure 8 is a diagram showing the correspondence between the lighting device and the irradiation surface of the uniform illumination scanning vision system of the present invention.

4. . . Uniformly illuminated scanning vision system

40. . . scanner

41. . . Lighting device

410, 411, 412, 413. . . Lighting unit

42. . . Laser unit

43. . . Detection unit

44. . . Visual imaging unit

45. . . Focusing lens

5. . . Irradiated surface

Claims (11)

A scanning system for uniformly illuminating, comprising: a scanner disposed above an illumination area and capturing the illumination area by rotating the lens; and a light-emitting device disposed in the illumination area At least two sides for projecting a light source toward the illumination area, such that each of the image capturing points obtained by the scanner has equal brightness, and the light-emitting device is provided with a lighting unit, wherein the light-emitting unit The device and the illumination region satisfy D=L-2(d2+d3)tan θ, wherein D is the width of the illumination region, and L is the distance from the light-emitting unit on the opposite side of the illumination region, and d2 is the distance The light-emitting unit is located at a height from the illumination area, d3 is the height of the light-emitting unit, and θ is the light-emitting angle of the light-emitting unit. The uniform illumination scanning vision system of claim 1, wherein the illumination area is square, and the polishing device is provided with four strip-shaped lighting units, and the four are A strip of light-emitting unit rings are placed on the four sides of the illuminated area. The uniform illumination scanning vision system of claim 1, wherein the illumination area is a square, and the light-emitting device is provided with two elongated light-emitting units for being disposed in the illumination area. The two opposite sides. The uniform illumination scanning vision system of claim 2, wherein the illumination unit and the illumination area are disposed between 80° and 100°. Uniformly lit scanning view as described in claim 2 or 3 The system is characterized in that the lighting unit has one or a plurality of light sources. The uniform illumination scanning vision system of claim 5, wherein the light source has a light emitting surface perpendicular to the illumination area. The uniform illumination scanning vision system of claim 1, wherein the illumination area is a square, and the light-emitting device is provided with two elongated light-emitting units for being disposed in the illumination area. Two adjacent sides. The uniform illumination scanning vision system of claim 1, wherein the illumination area is a square platform having an area greater than 180*180 mm ² . The uniform illumination scanning vision system according to claim 1, further comprising a laser unit, a detecting unit and a visual imaging unit for guiding the laser generated by the laser unit by the scanner Processing is performed to the illumination area, and the illumination area is imaged through the vision imaging unit and the detection unit. The uniform illumination scanning vision system of claim 1, wherein the scanner is provided with an electro-rotation element for imaging the illumination area by means of a rotating galvanometer. The uniform illumination scanning vision system of claim 1, wherein the scanner has a focusing lens facing the illumination area.