Collimation detection light source

Abstract

A collimation detection light source includes: a base; a plurality of first solid-state light-emitting elements arranged in a single row on the base and a plurality of second solid-state light-emitting elements arranged at intervals, wherein the first solid-state light-emitting elements include a first unit cell and a fluorescent portion that is photoluminescent by the first unit cell; a plurality of semi-cylindrical lenses arranged in a row along the aforementioned single row, the number corresponding to the first and second solid-state light-emitting elements, each semi-cylindrical lens having a cylindrical unidirectional collimating and refractive outer edge extending along a long axis, and the long axis being perpendicular to the aforementioned single row; a semi-cylindrical strip lens arranged on the base along a direction perpendicular to the long axis of the semi-cylindrical lens; a light-shielding member that blocks the light beam from entering the fluorescent portion of the first solid-state light-emitting element when the second solid-state light-emitting element is enabled to emit light; and exposes the first solid-state light-emitting element when the first solid-state light-emitting element is enabled to emit light.

Description

[Technical Field]

[0001] This invention relates to a detection light source, and more particularly to a collimated detection light source with a semi-cylindrical lens. [Previous Technology]

[0002] Cleanrooms are common facilities in fields such as food, optoelectronics, semiconductor production, biochemical technology, biotechnology, precision machinery, pharmaceuticals, and operating rooms in hospitals. In order to improve the quality, yield and reliability of products or experimental processes, the environmental conditions in cleanrooms must be strictly controlled. In addition to temperature, humidity and air quality, there are even stricter requirements for the number of micro-dust particles.

[0003] General micro-dust particles can be filtered out by filters during the repeated air convection process in the cleanroom; however, some special micro-dust particles, such as particles from cosmetics, static-charged particles from gloves or clothing, or even dust adhering to the oil on the human body surface, usually adhere to the work surface due to their slight adhesiveness. Even if a vacuum cleaner is used to remove them, the static electricity or oil on the dust itself may cause excessive adhesion, making it difficult to remove them from the surface to which they are attached; and if high-pressure air is used to remove the micro-dust adhering to the surface of the object, the micro-dust may be splashed to other places by the airflow, causing secondary contamination of the cleanroom.

[0004] On the other hand, it is impossible to accurately determine the quantity and location of micro-dust that is extremely difficult to observe with the naked eye. Even if it is required to be handled by manual wiping, it is still difficult to ensure that it can be effectively cleaned and removed. Even if light is added to assist lighting, the micro-dust may be too small, especially when the angle of the main incident light is too steep, and the work surface will also cause the light to reflect too strongly and directly enter the operator's eyes, thus affecting the judgment of the location of the micro-dust and whether it has been wiped clean.

[0005] As for semiconductor wafers and optical components, the smoothness or flatness of their surfaces not only affects product yield during manufacturing but also impacts efficiency and reliability during subsequent use. Therefore, they generally rely on Automated Optical Inspection (AOI) systems to determine the presence of defects. However, due to the high reflectivity of smooth surfaces, if an image is captured by a light source directly above the surface and an image capturing device is also positioned above it, the image of the defect may be completely obscured by the reflected light, making it impossible to detect. Therefore, as shown in Figure 1, the detection light source must incident the incident beam 92 from the side at a low angle α, and after illuminating the surface 90 of the object to be tested, the directly reflected beam 94, based on the law of reflection, exits from the other side at the same low angle α. This will not enter the image capture range or the observer's eye (labeled 9). Only then can the weak light diffused by the defects 96 or dust, as well as any possible fluorescence or phosphorescence, be identified and analyzed by the image capturing device.

[0006] To ensure the reliability of quantitative comparisons in the analysis records of defects and dust, the incident beam emitted by the aforementioned low-angle detection light source must not have a convergent or divergent illumination angle in the covered area; that is, a collimated light source must be selected. Unfortunately, the most common collimated light source is laser light, but because its energy is too concentrated and its illumination coverage is too small, it cannot provide a uniform light intensity over an illumination surface of, for example, several square centimeters. As for the most commonly used light source, such as LED light source, as shown in Figure 2, the chip 82 is generally placed on the circuit board 80, and the beam is converted from a more divergent light field to parallel light emission by a parabolic lens 84 in the direction of light emission.

[0007] However, on the one hand, parabolic lenses are extremely difficult to polish, resulting in poor manufacturing yield and output efficiency, and thus high prices, which is very unfavorable to manufacturing costs; on the other hand, even if a parabolic lens 84 is used to change the direction of light emission from the LED chip 82 to become a collimated light source, it is still impossible to change the fact that the energy is concentrated in the central part 86 of the light field and the energy is weaker in the edge part 88. This uneven illuminance distribution will produce uneven brightness and darkness on the light-illuminated plane, which is also not conducive to observation, monitoring or automated judgment.

[0008] Therefore, the main technical breakthrough of this invention is to provide a collimated detection light source that is more economical in manufacturing cost, has better product yield and output efficiency, and especially better meets the illumination uniformity required for actual optical inspection. [Summary of the Invention]

[0009] The detailed features and advantages of this invention are described in detail below in the embodiments. The content is sufficient to enable anyone skilled in the art to understand the technical content of this invention and implement it accordingly. Based on the content disclosed in this specification, the scope of the patent application and the drawings, anyone skilled in the art can easily understand the purpose and advantages of this invention.

[0010] One object of the present invention is to provide a collimated detection light source, which uses two sets of semi-cylindrical lenses arranged perpendicularly to each other to make the light beam emitted by each crystal form a slightly square light pattern. When arranged in a single row, it can provide a generally uniform strip illumination detection range.

[0011] Another object of the present invention is to provide a collimation detection light source, which, by means of optical path modulation formed by a semi-cylindrical lens structure, is easy to manufacture, has low cost and a yield rate much higher than that of a parabolic lens.

[0012] Another object of the present invention is to provide a collimation detection light source, which uses two different solid-state light-emitting elements, one of which emits light and automatically blocks the other, which has a fluorescent part, from being illuminated, thereby eliminating unexpected additional interference from the fluorescent part and making the independent illumination detection of the dual light sources more accurate and reliable.

[0013] To achieve the above objective, the collimation detection light source of the present invention includes a base; at least a plurality of first solid-state light-emitting elements disposed in a single row on the base and a plurality of second solid-state light-emitting elements arranged at intervals relative to the first solid-state light-emitting elements, wherein at least the first solid-state light-emitting elements include at least one first unit cell and a fluorescent portion photoluminescent by the first unit cell; a plurality of semi-cylindrical lenses arranged along the single row and the number corresponding to the first and second solid-state light-emitting elements, each of the semi-cylindrical lenses having a cylindrical unidirectional collimating and refractive outer edge extending along a long axis, and the long axis being perpendicular to the single row; a semi-cylindrical strip lens disposed on the base in a direction perpendicular to the long axis of the semi-cylindrical lens; at least one light-shielding member for blocking the light beam from entering the fluorescent portion of the first solid-state light-emitting element when the first number of second solid-state light-emitting elements are enabled to emit light; and for exposing the first solid-state light-emitting elements when the first solid-state light-emitting elements are enabled to emit light.

[0014] Since semi-cylindrical lenses can be manufactured using extruded or drawn light-transmitting materials, as long as the mold has a semi-edge conforming to, for example, a parabola, the light-transmitting material can be extruded or drawn into an elongated semi-cylindrical shape according to the mold shape, and cut along the axial direction to become semi-cylindrical lenses or semi-cylindrical strip lenses of different lengths and heights according to the required dimensions. The process is simple and the manufacturing cost is quite economical. In particular, the contour is easy to meet the requirements of optical configuration, and the quality is good and stable. The optical configuration formed by the two-way semi-cylindrical lenses can smoothly collide the light beam of the solid-state light-emitting element in a slightly square uniform light pattern, resulting in uniform illumination and facilitating low-angle illumination detection. Furthermore, due to the design of the light-shielding component, two different solid-state light-emitting elements can selectively emit light and prevent mutual interference. Even if one of them has a fluorescent part, the fluorescent part can be blocked from being illuminated and photoluminescence can be achieved when the other emits light, thereby ensuring the reliability of illumination detection. [Simplified Explanation of the Diagram]

[0015] Figure 1 is a schematic diagram of low-angle light source detection, illustrating the optical basis of low-angle illumination operation.

[0016] Figure 2 is a three-dimensional schematic diagram of a conventional LED element array paired with a corresponding parabolic lens, illustrating the light output pattern using a parabolic lens.

[0017] Figure 3 is a three-dimensional exploded view of the first preferred embodiment of the collimation detection light source of the present invention, illustrating the configuration of the first and second solid-state light-emitting elements, as well as the optical configuration of the semi-cylindrical lens, the semi-cylindrical strip lens and the light-shielding member.

[0018] Figures 4 and 5 are top views of the embodiment in Figure 3, illustrating the position and operation mode of the light-shielding member during the light emission detection of the first and second solid-state light-emitting elements, respectively.

[0019] Figure 6 is a three-dimensional assembly schematic diagram of the second preferred embodiment of the collimation detection light source of the present invention.

[0020] Figure 7 is a top view of the embodiment in Figure 6, illustrating the optical configuration of the semi-cylindrical lens, the semi-cylindrical strip lens, and the light-shielding member.

Implementation Method

[0021] Please refer to Figure 3, which is a first preferred embodiment of the collimation detection light source of the present invention. In this example, the base 1 is a hollow metal shell as a good heat dissipation frame, and a heat-conducting substrate (not labeled) is built inside. A plurality of first solid-state light-emitting elements 10 and second solid-state light-emitting elements 12 are arranged in a single row on the heat-conducting substrate. The first solid-state light-emitting elements 10 and second solid-state light-emitting elements 12 are arranged at a horizontal interval along the figure. A heat sink 14, exemplified as a heat dissipation fin, is provided behind the base 1. Therefore, the heat generated by the first solid-state light-emitting elements 10 and second solid-state light-emitting elements 12 can be conducted to the heat dissipation fin.

[0022] For ease of explanation, the first solid-state light-emitting element 10 in this example is three white LEDs. Referring to FIG4, the first solid-state light-emitting element 10 includes a first cell 100 that emits, for example, blue light and a fluorescent part 102 that emits, for example, yellow light when excited by the blue light of the first cell. In this example, the second solid-state light-emitting element 12 is three ultraviolet LEDs. Since ultraviolet light has a short wavelength and high frequency, once it is incident on the fluorescent part 102 of the first solid-state light-emitting element 10, it will also excite yellow light, thereby interfering with the weak beam of light diffusely reflected by the defects or dust when the ultraviolet light irradiates the surface defects or dust to be detected. Therefore, if the second solid-state light-emitting element 12 is to be lit, it is necessary to block the ultraviolet light from entering the fluorescent part or the light emitted after the fluorescent part is irradiated.

[0023] In front of the first solid-state light-emitting element 10 and the second solid-state light-emitting element 12, a row of multiple semi-cylindrical lenses 20 arranged horizontally along the aforementioned single row is provided. In this example, the semi-cylindrical lenses 20 are also arranged in three pieces, and the long axis 22 of the semi-cylindrical lenses 20 extends along the longitudinal direction in the figure. Therefore, when viewed from above as shown in Figure 4, the cylindrical unidirectional collimating and refractive outer edge 24 of each semi-cylindrical lens 20 can be seen. That is, the light beam emitted by the rear solid-state light-emitting element will be collimated from bottom to top along Figure 4 after passing through the semi-cylindrical lenses 20, forming a uniform light distribution along the transverse direction of the base 1. Further forward, a semi-cylindrical strip lens 3 is provided. The semi-cylindrical strip lens 3 is arranged in the aforementioned base 1 with its optical axis perpendicular to the long axis 22 of each semi-cylindrical lens 20, so that the light beam transmitted from the semi-cylindrical lenses 20 also forms a collimated and uniform light beam emitted along the longitudinal direction of the base 1. Thus, the light beam emitted by each of the first solid-state light-emitting element 10 or the second solid-state light-emitting element 12, after passing through the two semi-cylindrical lenses 20 and the semi-cylindrical strip lens 3 arranged in a horizontal and vertical direction, will present as a square or rectangular uniform light beam. This ensures that the surface of the wafer under test, the device under test, or the equipment under test is uniformly illuminated during the inspection. Any automated optical acquisition device can obtain a uniform background, making it easy to identify and record the diffuse reflection light of defects or dust.

[0024] In this example, the three semi-cylindrical lenses 20 are respectively disposed at the positions of the three light-transmitting holes 40 on an actuating plate 2, and the light-shielding member 4 is a plurality of light-shielding sheets 42 disposed on the back of the actuating plate 2, and the light-transmitting holes 40 are defined by the light-shielding sheets 42. Therefore, as shown in Figures 4 and 5, when the ultraviolet light emitted by the second solid-state light-emitting element 12 is used as the detection light, the light-shielding sheet 42 will block the front and sides of the first solid-state light-emitting element 10 to prevent any ultraviolet light from entering the fluorescent part 102 of the first solid-state light-emitting element 10 and generating additional yellow light. The second solid-state light-emitting element 12 is directly facing the light-transmitting holes 40 and the semi-cylindrical lenses 20, so that the ultraviolet light beam is collimated by the corresponding semi-cylindrical lenses 20 and semi-cylindrical strip lenses 3 into a transverse detection beam composed of three square uniform beams; in particular, it can be used to detect substances with fluorescent reactions, such as bloodstains or fluorescent proteins.

[0025] In contrast, if the white light is to illuminate the same detection range and light up the first solid-state light-emitting element 10, the light-shielding plate 42 will block the front and side of the second solid-state light-emitting element 12, and expose the first solid-state light-emitting element 10 to the light-transmitting hole 40, facing the position of the semi-cylindrical lens 20. The white light beam is thus collimated by the corresponding semi-cylindrical lens 20 and semi-cylindrical strip lens 3 into a transverse detection beam composed of three square uniform beams.

[0026] Of course, as those skilled in the art can easily understand, the wavelength of the above-mentioned solid-state light-emitting element is not a fixed limiting condition, and the structure of the light-shielding sheet does not necessarily have to be integrated with the semi-cylindrical lens. The second preferred embodiment of the present invention is shown in Figures 6 and 7, wherein the first solid-state light-emitting element 10' is, for example, a fluorescent and electroluminescent crystal made of quantum dot nanocomposite light-emitting material, and the second solid-state light-emitting element 12' is paired with, for example, an organic light-emitting semiconductor with green light; the semi-cylindrical lens 20' is respectively disposed in front of each of the first solid-state light-emitting element 10' and the second solid-state light-emitting element 12'; further in front is the semi-cylindrical strip lens 3'. The light-shielding member 4' is disposed in front of the first solid-state light-emitting element 10' and the second solid-state light-emitting element 12' and behind the semi-cylindrical lens 20', taking a baffle (not labeled) as an example, and forming a number of light-transmitting holes 40' in it that are half the number of those of the semi-cylindrical lens 20'; therefore, only the light-shielding member 4' moves left and right relative to the base 1'. When the first solid-state light-emitting element 10' is to be lit, the light-transmitting hole 40' of the light-shielding member 4' is aligned with the first solid-state light-emitting element 10', allowing the light-shielding plate 42' to block the second solid-state light-emitting element 12' while exposing the first solid-state light-emitting element 10'. Conversely, when the second solid-state light-emitting element 12' is to be lit, the light-shielding member 4' is moved to block the first solid-state light-emitting element 10', ensuring that the first cell 100' and the fluorescent part 102' are not illuminated and do not emit fluorescent interference. When the detection light source requires more different colors of light, more third and fourth solid-state light-emitting elements can be arranged in the horizontal row on the thermally conductive substrate, as long as the light-shielding member can selectively block the non-emitting light-emitting elements and expose the appropriate light-emitting elements each time. Even arranging a second row in addition to the first row in the vertical direction does not exceed the structure of this invention and provides greater application flexibility.

[0027] In this way, the overall collimation detection light source structure is simple, and two or more different light sources can be selected. In particular, the use of extruded or drawn semi-cylindrical lenses and semi-cylindrical strip lenses not only has low manufacturing cost, but also allows the focal length to be changed with the mold. As long as the longitudinal and transverse directions are substantially perpendicular to each other, the light beam emitted by each independent light-emitting element can be shaped into a square or rectangular uniform collimated light shape, and the overall structure creates a uniform collimated light source, which meets the requirements of low-angle light emission detection.

[0028] However, the above description is only a preferred embodiment of the present invention and should not be construed as limiting the scope of the present invention. All simple equivalent changes and modifications made in accordance with the scope of the patent application and the contents of the specification of the present invention should still fall within the scope of the patent of the present invention.

Claims

1. A collimation detection light source, comprising: A base; At least a plurality of first solid-state light-emitting elements are arranged in a single row on the aforementioned base and a plurality of second solid-state light-emitting elements are arranged at intervals relative to the aforementioned first solid-state light-emitting elements, wherein at least the aforementioned first solid-state light-emitting elements include at least one first unit cell and a fluorescent portion that is photoluminescent by the aforementioned first unit cell; A plurality of semi-cylindrical lenses arranged along the aforementioned single row, the number corresponding to the aforementioned first and second solid-state light-emitting elements, each of the aforementioned semi-cylindrical lenses having a cylindrical unidirectional collimating and refractive outer edge extending along a long axis, and the aforementioned long axis being perpendicular to the aforementioned single row; A semi-cylindrical strip lens is disposed on the aforementioned base along a direction perpendicular to the long axis of the aforementioned semi-cylindrical lens; At least one light-shielding member is provided to block the light beam from entering the fluorescent portion of the first solid-state light-emitting element when the second solid-state light-emitting element is enabled to emit light; and to expose the first solid-state light-emitting element when the first solid-state light-emitting element is enabled to emit light.

2. The collimation detection light source as claimed in claim 1, wherein the aforementioned base further includes at least one heat sink that thermally connects the aforementioned first solid-state light-emitting element and the aforementioned second solid-state light-emitting element.

3. The collimation detection light source as described in claim 2, wherein the number of the aforementioned semi-cylindrical lenses is equal to the sum of the number of the aforementioned first solid-state light-emitting elements and the aforementioned second solid-state light-emitting elements, such that a semi-cylindrical lens is respectively provided in front of each of the aforementioned first solid-state light-emitting elements and each of the aforementioned solid-state light-emitting elements.

4. The collimation detection light source as described in claim 2, wherein each of the aforementioned semi-cylindrical lenses corresponds to one of the aforementioned first solid-state light-emitting elements and one of the aforementioned second solid-state light-emitting elements.

5. The collimation detection light source as described in claims 1, 2, 3 or 4, wherein the aforementioned light-shielding member is a baffle with a plurality of light-transmitting perforations, movable along a direction perpendicular to the aforementioned long axis between a position that shields the aforementioned first solid-state light-emitting element and a position that shields the aforementioned second solid-state light-emitting element.

6. The collimation detection light source as described in claim 5, wherein the aforementioned baffle further includes a plurality of light-shielding sheets corresponding to the aforementioned light-transmitting perforations.

7. The collimation detection light source as described in claim 1, 2, 3 or 4, wherein the aforementioned light-shielding member is a baffle formed with a plurality of light-shielding sheets.

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