CN211856382U - Detection device for simultaneous equal optical path imaging and equal illumination illumination on both sides of die - Google Patents

Abstract

The utility model is a detection device for simultaneous equal optical path imaging and equal illumination illumination on both sides of crystal grains. The device comprises a camera, a telecentric imaging lens, a combined image optical element and a semiconductor crystal grain, which are sequentially arranged in the direction of the vertical optical path. The two sides between the imaging optical element and the semiconductor die are provided with trapezoidal relay prisms, and the two sides of the semiconductor die are respectively imaged in different areas on the camera sensor surface with double optical paths through the trapezoidal relay prism and the combining optical element. Position, the utility model replaces two independent right-angle relay prisms with a single image combination optical element to realize the image combination function of the double-sided imaging optical path. Higher precision.

Description

Detection device for simultaneous equal optical path imaging and equal illumination illumination on both sides of die

Technical field:

The utility model belongs to the field of optical detection and machine vision, and in particular relates to a detection device based on imaging optical elements for simultaneous equal optical path imaging on both sides of crystal grains and equal illumination illumination.

Background technique:

The applicant's previous application, title: "Optical detection device and method for realizing equal optical path imaging of semiconductor die relative to two surfaces" Application number: "2019113692573, wherein the synthesis of the images on the opposite sides of the die in the CCD sensor requires two pieces based on A right-angle reflecting prism with total reflection (as shown in Figure 1), or a right-angle double-sided reflecting prism (as shown in Figure 2); the former has higher technical difficulty requirements for the precise assembly and debugging of the right-angle reflecting prism, while the latter requires Coating high-reflection reflective film and reliability is not a priority option. In addition, the 45-degree edge of the right-angle reflective prism will inevitably have broken edges and corners during processing, and two adjacent defective edges will affect the double Face recognition and imaging quality, so it is necessary to find a solution with controllable double-sided imaging interval and good component manufacturing process.

In addition, the applicant has previously applied for two patents, patent title: "Method for obtaining complete equal-illuminance illumination for optical detection of opposite sides of semiconductor die", patent application number: "2019113692588; and patent title: "For semiconductor die dual A new illumination compensation method for the simultaneous detection of surface defects", patent application number: "201911315115.9, the double-sided imaging optical paths proposed in these two patent applications both require the addition of specific illumination optical elements (optical wedge or right angle) on the right-angle relay prism. beamsplitter prism) for the purpose of double-sided imaging iso-illuminance illumination, as shown in Fig. 3a, b, c, the illumination light source system of Fig. 3a requires an optical wedge and increases the complexity of the mechanical structure; the illumination of Fig. 3b, 3c The light source system requires a right angle beamsplitter prism and thus produces a 50% loss of light energy.

Invention content:

In view of the above-mentioned problems, the present utility model proposes a detection device based on the double-sided simultaneous equal-optical path imaging and equal-illuminance illumination of the crystal grains of the image-combining optical element. A single image combining optical element replaces two independent right-angle relay prisms to realize the combined image function of the double-sided imaging optical path. The structure is simple, the debugging is easier and more convenient, and the double-sided image combining accuracy is higher.

The utility model is a detection device based on the simultaneous equal-optical path imaging and equal-illuminance illumination on both sides of the crystal grains of the image-combining optical element, which is characterized in that the detection device comprises a camera, a telecentric imaging lens, and an image-combining optical element, which are sequentially arranged in the direction of the vertical optical path. And the semiconductor die, the two sides between the combined imaging optical element and the semiconductor die are provided with a trapezoidal relay prism, and the two sides of the semiconductor die are respectively imaged by the trapezoidal relay prism and the combined imaging optical element with dual optical paths Different area locations on the camera sensor surface.

The utility model is a detection device based on the simultaneous equal-optical path imaging and equal-illuminance illumination on both sides of the crystal grains of the image-combining optical element, which is characterized in that the detection device comprises a camera, a telecentric imaging lens, and an image-combining optical element, which are sequentially arranged in the direction of the vertical optical path. and semiconductor crystal grains, the upper and lower sides between the combined imaging optical element and the semiconductor crystal grains are provided with trapezoidal relay prisms, and the top and bottom surfaces of the semiconductor crystal grains are respectively provided with the trapezoidal relay prisms and the combined imaging optical elements. Dual optical paths image different regions on the camera sensor surface.

Further, the sky surface of the above-mentioned combined image optical element close to the camera is a plane, which is the combined image output surface of the dual optical paths, the sky surface of the combined image optical element is perpendicular to the optical axis of the camera, and the left plane and the right plane of the combined image optical element are respectively. It is a dual optical path imaging input surface and is parallel to the optical axis of the camera. The center of the bottom surface of the combined imaging optical element is far from the camera and perpendicular to the optical axis. The center of the aperture is a 90-degree total reflection surface, and the 90-degree total reflection surface forms a V shape. Total reflection surface inside the groove.

Further, the above-mentioned imaging optical element is in the shape of a cuboid, and its size is 20x10x20mm, wherein the height of the apex of the total reflection surface in the V-shaped groove on the bottom surface to the bottom surface is 5mm.

Further, adjust the position of the imaging optical element along the optical axis of the camera, and the interval between the double-sided images of the die on the output surface is △≈d+a=3.3mm, where the edges of the double-sided images of the die that are close to each other are between the edges. The distance between them is d=2mm, the size of the grain is a=1.3mm, and the distance from the center of the grain to be measured on the input surface to the vertex of the right-angle reflection surface is △/2.

Further, the above-mentioned imaging optical element is formed by molding glass or optical plastic, or two pieces of right-angle reflecting prisms are processed and glued together, or the two spliced surfaces are bonded together by a light gluing method.

Further, the side of the above-mentioned trapezoidal relay prism away from the optical axis of the camera is the small end, which is the sky surface of the trapezoidal relay prism, and the side close to the optical axis of the camera is the large end, which is the bottom surface of the trapezoidal relay prism. The top surface and bottom surface of the prism are optical surfaces, and the two inclined surfaces are total reflection surfaces. The function of the aperture edge of the bottom surface of the trapezoidal relay prism is the image relay function.

Further, the above device is provided with an illumination light source, and the illumination light source is located on the side of the trapezoidal relay prism away from the direction of the optical axis of the camera.

The utility model is a detection method based on the double-sided simultaneous equal-optical path imaging and equal-illuminance illumination of the crystal grains based on the image-combining optical element. The detection device for illumination includes a camera, a telecentric imaging lens, an imaging optical element and a semiconductor die that are sequentially arranged in the direction of the vertical optical path, and trapezoidal relays are arranged on both sides between the imaging optical element and the semiconductor die. Prism, the two sides of the semiconductor die are imaged in different areas on the sensor surface of the camera with dual optical paths through the trapezoidal relay prism and the combining optical element respectively; during operation, the left side of the illuminated semiconductor die passes through the trapezoid successively. The 180-degree rotation of the two inclined surfaces of the relay prism, and then the 90-degree image rotation of the combining optical element, is imaged on the left half area of the camera sensor surface by the telecentric imaging lens; for the right side of the semiconductor die, After passing through the two inclined surfaces of another trapezoidal relay prism and combining optical elements, the telecentric imaging lens is imaged onto the right half of the sensor surface of the camera; the left side and the left side of the semiconductor die are also obtained from the imaging surface of the camera. The image on the right side of the semiconductor die is separated by a small distance from the image on the left side of the semiconductor die and the image on the right side of the semiconductor die.

The utility model is a detection method based on the double-sided simultaneous equal-optical path imaging and equal-illuminance illumination of the crystal grains based on the image-combining optical element. The detection device for illumination includes a camera, a telecentric imaging lens, an imaging optical element, and a semiconductor die that are sequentially arranged in the direction of the vertical optical path, and the upper and lower sides between the imaging optical element and the semiconductor die are provided with trapezoids. The relay prism, the top and bottom surfaces of the semiconductor die are respectively imaged in different areas on the camera sensor surface by the trapezoidal relay prism and the combining optical element with dual optical paths; during operation, the top surface of the illuminated semiconductor die is successively After the 180-degree rotation of the two inclined surfaces of the trapezoidal relay prism, and the 90-degree rotation of the combining optical element, the telecentric imaging lens is imaged on the left half area of the camera sensor surface; for the bottom surface of the semiconductor die, After passing through the two inclined surfaces of another trapezoidal relay prism and the combining optical element, the telecentric imaging lens is used to image the right half of the sensor surface of the camera; the top and bottom surfaces of the semiconductor die are also obtained from the imaging surface of the camera. , and there is a small distance between the image of the top surface of the semiconductor die and the image of the bottom surface of the semiconductor die.

The technical advantages of the present utility model are as follows:

①Replace two independent right-angle relay prisms with a single image combination optical element to realize the image combination function of the double-sided imaging optical path.

②The combined image optical elements still use total reflection to realize the image transfer function, and there is no need for the reflective surface to be coated with a medium high-reflection film or other high-reflection films like a single right-angle double-sided reflective prism.

③The interval between the images on both sides of the grain is adjustable and controllable, which can be realized by fine-tuning the optical element of the combined image along the direction of the optical axis.

④ The use of the trapezoidal relay prism simplifies the illumination light source system. This solution is simpler in structure and easier to assemble and debug than the illumination light source system (Fig. Higher energy utilization and lower cost.

Description of drawings:

Figures 1, 2, 3a, 3b, and 3c are the existing devices for optically detecting the surface of semiconductor crystal grains;

Figures 4 and 4b are the device for optical detection of the two sides of the semiconductor die according to the present invention;

Fig. 5 is the size parameter diagram of the combined image optical element;

Fig. 6 is a size parameter diagram of a trapezoidal relay prism.

Detailed ways:

The detection device of the present utility model based on the double-sided simultaneous equal optical path imaging and equal illumination illumination of the crystal grains of the combined imaging optical element comprises a camera 1, a telecentric imaging lens 2, a combined imaging optical element 3 and a semiconductor sequentially arranged in the direction of the vertical optical path. Die 4, the semiconductor die 4 can be supported on the stage 5, the two sides between the combined imaging optical element and the semiconductor die are provided with a trapezoidal relay prism 6, and the two sides 401 of the semiconductor die Different regions and positions on the sensor surface of the camera 1 are imaged by dual optical path imaging through the two trapezoidal relay prisms 6a, 6b and the combining optical element 3 respectively.

Alternatively, the detection device of the present invention based on the simultaneous equal optical path imaging on both sides of the crystal grains of the combined imaging optical element and the equal illumination illumination includes a camera 1, a telecentric imaging lens 2, and an imaging optical element 3 sequentially arranged in the direction of the vertical optical path. And the semiconductor crystal grain 4, the semiconductor crystal grain 4 can be supported on the stage 5, the upper and lower sides between the combined image optical element 3 and the semiconductor crystal grain 4 are provided with a trapezoidal relay prism 6, and the semiconductor crystal grain 4 is provided with a trapezoidal relay prism 6. The top surface 402 and the bottom surface 403 of the particle are respectively imaged on different regions on the sensor surface of the camera 1 through two trapezoidal relay prisms 6a, 6b and the combining optical element 3 with dual optical paths.

The structures of the combined image optical element 3 and the trapezoidal relay prism 6 will be specifically described below.

The sky surface 301 of the combined image optical element close to the camera is a plane, which is the combined image output surface of the dual optical paths. The sky surface of the combined image optical element is perpendicular to the optical axis of the camera, and the left plane 302 and the right plane 303 of the combined image optical element are respectively: The dual-optical path imaging input surface is parallel to the optical axis K of the camera. The center of the bottom surface of the combined imaging optical element is far from the camera and perpendicular to the optical axis K. The center of the bottom surface is a total reflection surface that forms 90 degrees with each other, and the total reflection surfaces that form 90 degrees form V Total reflection surface inside the groove.

The combined imaging optical element is in the shape of a cuboid, and its size is 20x10x20mm, of which the height of the apex of the total reflection surface in the V-shaped groove on the bottom surface to the bottom surface is 5 mm; the combined imaging optical element is molded by glass or optical plastic, or two right angle reflecting prisms It is made of glued and spliced by processing, or the two spliced surfaces are bonded together by light gluing method.

By moving the imaging optical element 3 along the optical axis, the interval between the images on the camera sensor on both sides of the semiconductor die can be adjusted. The selection of the interval size needs to be reasonable, too small is inconvenient for image recognition processing, and too large will affect the The field of view of the lens.

The optical prism assembly with the dual optical path combining function of the present application is placed in an appropriate position before the imaging lens, so as to obtain the desired double-sided image on the sensor of the imaging lens.

Further, adjust the position of the imaging optical element along the optical axis of the camera, and the interval between the double-sided images of the die on the output surface is △≈d+a=3.3mm, where the edges of the double-sided images of the die that are close to each other are between the edges. The distance between them is d=2mm, the size of the grain is a=1.3mm, and the distance from the center of the grain to be measured on the input surface to the vertex of the right-angle reflection surface is △/2.

The side of the trapezoidal relay prism 6 away from the optical axis of the camera is the small end, which is the sky surface 601 of the trapezoidal relay prism, and the side close to the optical axis of the camera is the big end, which is the bottom surface 602 of the trapezoidal relay prism. The top surface and the bottom surface are optical surfaces, the two inclined surfaces 603 are total reflection surfaces, the function of the aperture edge of the bottom surface of the trapezoidal relay prism is the image relay function, and the middle part of the top surface and the bottom surface is the transmission light path of the illumination light source.

The device of the present application is provided with illumination light sources 7a, 7b, and the illumination light source is located on the side of the trapezoidal relay prism away from the direction of the optical axis of the camera; the above-mentioned camera is a camera with a sensor CCD or CMOS.

Taking FIG. 4 as an example, the present invention is based on a detection method for simultaneous equal optical path imaging and equal illumination illumination on both sides of the crystal grains of the combined image optical element, and the detection device comprises a camera 1, a telecentric imaging, and a The lens 2, the combined imaging optical element 3 and the semiconductor crystal grain 4, the semiconductor crystal grain 4 can be supported on the stage 5, and the two sides between the combined imaging optical element and the semiconductor crystal grain are provided with a trapezoidal relay prism 6. The two side surfaces 401 of the semiconductor die are respectively imaged in different regions on the sensor surface of the camera 1 through the two trapezoidal relay prisms 6a, 6b and the combining optical element 3 with dual optical paths; during operation, the illuminated semiconductor The left side of the die passes through the 180-degree image rotation of the two inclined surfaces of the trapezoidal relay prism, and then passes through the 90-degree image rotation of the combining optical element, and is imaged on the left half area of the camera sensor surface by the telecentric imaging lens; For the right side of the semiconductor die, after passing through the two inclined surfaces of another trapezoidal relay prism and the combining optical element, the telecentric imaging lens will image the right half of the sensor surface of the camera; from the imaging surface of the camera, it will also be The images of the left side and the right side of the semiconductor die are obtained, and there is a small distance between the image of the left side of the semiconductor die and the image of the right side of the semiconductor die.

Similarly, for the simultaneous detection of the two opposite surfaces of the top and bottom surfaces of the semiconductor die, a similar detection device can also be applied, but the trapezoidal relay prism needs to be placed on the top and bottom sides of the semiconductor die respectively, and the camera 1. The imaging lens 2 and the imaging optical element 3 are arranged on the semiconductor die in the direction of the horizontal optical path, as shown in FIG. The detection device for isoillumination illumination includes a camera 1, a telecentric imaging lens 2, an imaging optical element 3, and a semiconductor die 4, which are sequentially arranged in the vertical optical path direction. The semiconductor die 4 can be supported on the stage 5, so the The upper and lower sides between the combined image optical element 3 and the semiconductor die 4 are provided with trapezoidal relay prisms 6, and the top surface 402 and the bottom surface 403 of the semiconductor die are respectively provided with two trapezoidal relay prisms 6a, 6b, The image optical element 3 is imaged in different areas on the sensor surface of the camera 1 with dual optical paths; during operation, the sky surface of the illuminated semiconductor die passes through the 180-degree image rotation of the two inclined surfaces of the trapezoidal relay prism, and then passes through the combined image. After the 90-degree relay of the optical element, the telecentric imaging lens is used to image the left half area of the camera sensor surface; for the bottom surface of the semiconductor die, after passing through the two inclined surfaces of another trapezoidal relay prism and the combined imaging optical element, The telecentric imaging lens is imaged on the right half area of the camera sensor surface; the images of the top and bottom surfaces of the semiconductor die are also obtained from the imaging surface of the camera, and the images of the top surface of the semiconductor die and the bottom surface of the semiconductor die are also obtained. There is a small gap between them.

The technical advantages of the present utility model are as follows:

①Replace two independent right-angle relay prisms with a single image combination optical element to realize the image combination function of the double-sided imaging optical path.

②The combined image optical elements still use total reflection to realize the image transfer function, and there is no need for the reflective surface to be coated with a medium high-reflection film or other high-reflection films like a single right-angle double-sided reflective prism.

③The interval between the images on both sides of the grain is adjustable and controllable, which can be realized by fine-tuning the optical element of the combined image along the direction of the optical axis.

④ The use of the trapezoidal relay prism simplifies the illumination light source system. This solution is simpler in structure and easier to assemble and debug than the illumination light source system (Fig. Higher energy utilization and lower cost.

Finally it should be noted that: the above embodiment is only used to illustrate the technical scheme of the present invention and not to limit it; although the present invention has been described in detail with reference to the preferred embodiment, those of ordinary skill in the art should understand: still The specific embodiments of the present invention can be modified or some technical features can be equivalently replaced; without departing from the spirit of the technical solutions of the present invention, all of them should be included in the scope of the technical solutions claimed in the present invention.

Claims (8)

1. A detection device for crystal grain double-sided simultaneous aplanatic imaging and isoluminance illumination is characterized in that: the imaging device comprises a camera, a telecentric imaging lens, an image combination optical element and a semiconductor crystal grain which are sequentially arranged in the direction perpendicular to an optical path, wherein trapezoidal image rotating prisms are arranged at two side parts between the image combination optical element and the semiconductor crystal grain, and two side surfaces of the semiconductor crystal grain are imaged at different area positions on the surface of a camera sensor through the trapezoidal image rotating prisms and the image combination optical element in a double optical path mode.

2. A detection device for crystal grain double-sided simultaneous aplanatic imaging and isoluminance illumination is characterized in that: the imaging device comprises a camera, a telecentric imaging lens, an image combination optical element and a semiconductor crystal grain which are sequentially arranged in the direction perpendicular to an optical path, wherein trapezoidal image rotating prisms are arranged on the upper side and the lower side between the image combination optical element and the semiconductor crystal grain, and the top surface and the bottom surface of the semiconductor crystal grain are imaged in different area positions on the surface of a camera sensor through the trapezoidal image rotating prisms and the image combination optical element in a double-optical-path mode.

3. The apparatus for detecting die double-sided simultaneous aplanatic imaging and isoluminance illumination as claimed in claim 1 or 2, wherein: the top surface of the image combination optical element, which is close to the camera, is a plane and is a combined image output surface of the double light paths, the top surface of the image combination optical element is perpendicular to the optical axis of the camera, the left plane and the right plane of the image combination optical element are respectively double light path imaging input surfaces and are parallel to the optical axis of the camera, the center of the aperture of the bottom surface of the image combination optical element, which is far away from the camera and is perpendicular to the optical axis, is a total reflection surface which forms 90 degrees with each other, and the total reflection surfaces which form 90 degrees with each other form a V-shaped groove.

4. The die double-sided simultaneous aplanatic imaging and isolux illumination detection apparatus as claimed in claim 3, wherein: the image combining optical element is in a cuboid shape, the size of the image combining optical element is 20x10x20mm, and the height from the vertex of the total reflection surface in the V-shaped groove of the bottom surface to the bottom surface is 5 mm.

5. The die double-sided simultaneous aplanatic imaging and isolux illumination detection apparatus as claimed in claim 3, wherein: and adjusting the position of the image combination optical element along the optical axis direction of the camera, wherein the interval between the double-sided imaging of the crystal grains on the output surface is delta & lt d + a =3.3mm, the interval between the edges of the double-sided imaging of the crystal grains close to each other is d =2mm, the size of the crystal grains is a =1.3mm, and the distance from the center of the to-be-measured surface of the crystal grains to the vertex of the right-angle reflecting surface on the input surface is delta/2.

6. The die double-sided simultaneous aplanatic imaging and isolux illumination detection apparatus as claimed in claim 3, wherein: the image combination optical element is formed by molding glass or optical plastic, or is formed by processing, gluing and splicing two right-angle reflecting prisms, or two spliced surfaces are bonded into a whole by a light gluing method.

7. The apparatus for detecting die double-sided simultaneous aplanatic imaging and isoluminance illumination as claimed in claim 1 or 2, wherein: the trapezoidal image rotating prism is a small end which is the top surface of the trapezoidal image rotating prism at the side far away from the optical axis of the camera, a big end which is the bottom surface of the trapezoidal image rotating prism at the side near the optical axis of the camera, the top surface and the bottom surface of the trapezoidal image rotating prism are optical surfaces, the two inclined surfaces are total reflection surfaces, the aperture edge of the bottom surface of the trapezoidal image rotating prism is used for image rotating, and the middle part of the top surface and the bottom surface is a transmission light path of an illumination light source.

8. The apparatus for detecting die double-sided simultaneous aplanatic imaging and isoluminance illumination as claimed in claim 1 or 2, wherein: the device is provided with an illumination light source, and the illumination light source is positioned on one side of the trapezoidal image rotating prism, which is far away from the direction of the optical axis of the camera.

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