Laser measurement method and laser measuring device

Abstract

To provide a laser measurement method capable of avoiding interference of laser beams and a position deviation tolerance of a laser.SOLUTION: A laser measurement method has multiple pins 3 erected from one surface of a base material 2, and measures the height of the multiple pins 3 by applying laser beams to a measured object 1A arranged at an interval each in a first direction D1 and a second direction D2 in which the multiple pins 3 cross mutually within the surface of the base material 2, scanning the inside of the surface of the base material 2 with laser beams, and measuring laser beams reflected by and returned from the measured object 1A. In the laser measurement method, the height of the multiple pins 3 is measured by applying laser beams in a third direction D3 in which the interval between the two mutually adjacent pins 3 is larger than the interval in the first direction D1 and the interval in the second direction D2 from among four mutually adjacent pins 3 in the first direction D1 and the second direction D2.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a laser measurement method and a laser measurement device. [Background technology]

[0002] For example, the heat sink has fins (so-called pin fins) that stand up in a pin-like (columnar) shape from one side of a plate-shaped base material (substrate), and these multiple pin fins are arranged in a staggered or lattice pattern with spaces between each other in directions that intersect with each other within the surface of the substrate.

[0003] Incidentally, in a heat sink equipped with such pin fins, the height of the pin fins is measured using a laser measuring device (see, for example, Patent Document 1 below).

[0004] Specifically, the height of multiple pin fins is measured by irradiating a laser beam onto a heat sink, scanning the laser beam across the surface of the substrate, and measuring the laser beam that is reflected back from the heat sink. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2013-102053 A Summary of the Invention [Problem to be solved by the invention]

[0006] However, with the conventional laser measurement method described above, when measuring the height from the base of the pin fin, the spot of laser light irradiated between the pin fins can interfere with adjacent pin fins, making it difficult to accurately measure the height of multiple pin fins.

[0007] On the other hand, if the spot diameter of the laser light is reduced to avoid interference of the laser light between adjacent pin fins, the tolerance for misalignment of the laser light with respect to the pin fins when scanning with the laser light will decrease.

[0008] In particular, as the spacing between adjacent pin fins becomes narrower, it becomes necessary to irradiate the pin fins with a laser beam having a spot diameter smaller than the spacing in order to avoid interference between the pin fins, which reduces the tolerance for positional deviation of the laser beam.

[0009] The present invention has been proposed in view of the above-mentioned conventional circumstances, and has an object to provide a laser measurement method and laser measurement apparatus that make it possible to increase the tolerance for positional deviation of laser light while avoiding interference of laser light. [Means for solving the problem]

[0010] In order to achieve the above object, the present invention provides the following means. [1] A laser measurement method for measuring heights of a plurality of pins by irradiating a laser beam onto a measurement object having a plurality of pins standing on one surface of a base material, the plurality of pins being arranged at intervals in a first direction and a second direction intersecting each other within the surface of the base material, and measuring the laser beam reflected and returning from the measurement object while scanning the laser beam within the surface of the base material, the method comprising: a laser measurement method for measuring heights of the pins while scanning the laser light in a third direction in which a distance between two adjacent pins among four pins adjacent to each other in the first direction and the second direction is greater than the distance in the first direction and the distance in the second direction. [2] The laser measurement method according to [1], wherein the laser light is irradiated onto the object to be measured while being focused. [3] The laser measurement method according to [2], wherein a spot diameter of the laser light is made smaller than a gap formed between three adjacent pins among the four pins. [4] The laser measurement method according to [1], wherein the plurality of pins are arranged in a staggered manner within the surface of the base material. [5] The laser measurement method according to [1], wherein the plurality of pins are arranged in a lattice pattern within the surface of the base material. [6] The laser measurement method according to [1], wherein the object to be measured is a heat sink. [7] A laser measurement device that irradiates a laser beam onto a measurement object having a plurality of pins standing on one surface of a base material, the plurality of pins being arranged at intervals in a first direction and a second direction intersecting each other within the surface of the base material, and measures heights of the plurality of pins by scanning the laser beam within the surface of the base material and measuring the laser beam reflected and returning from the measurement object, comprising: an optical unit that irradiates the object to be measured with laser light; A scanning unit that scans the laser light within a surface of the base material; a light receiving unit that receives the laser light reflected and returned from the object to be measured; a calculation unit that calculates and measures heights of the pins based on a measurement result of the laser light received by the light receiving unit, the scanning unit scans the laser light in a third direction in which a distance between two adjacent pins among four pins adjacent to each other in the first direction and the second direction is greater than the distance in the first direction and the distance in the second direction. [8] The laser measurement device according to [7], wherein the optical unit irradiates the laser light onto the object to be measured while concentrating the laser light. [9] The laser measurement device according to [8], wherein the optical unit sets a spot diameter of the laser light to be smaller than a gap formed between three adjacent pins among the four pins. Effect of the Invention

[0011] As described above, according to the present invention, there is provided a laser measurement method and a laser measurement device that can increase the tolerance for laser positional deviation while avoiding interference of laser light. [Brief description of the drawings]

[0012] [Figure 1] FIG. 2 is a plan view of a heat sink for explaining the laser measurement method according to the first embodiment of the present invention. [Diagram 2] FIG. 2 is a side view of the heat sink shown in FIG. [Diagram 3] 2 is a plan view showing dimensions of each portion of adjacent pin fins of the heat sink shown in FIG. 1. [Figure 4] FIG. 2 is a schematic diagram showing a configuration of a laser measurement device. [Diagram 5] 7 is a side view showing a state in which the heat sink shown in FIG. 1 or 6 is irradiated with laser light. FIG. [Figure 6] 2 is a plan view for explaining a spot diameter of a laser beam irradiated onto the heat sink shown in FIG. 1. FIG. [Figure 7] FIG. 11 is a plan view of a heat sink for explaining a laser measurement method according to a second embodiment of the present invention. [Figure 8] 11 is a graph showing the results of measuring the height of multiple pin fins of a heat sink using a laser measurement method of an embodiment. [Figure 9] 13 is a graph showing the results of measuring the height of multiple pin fins of a heat sink using a laser measurement method of the comparative example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. In addition, the drawings used in the following description may show characteristic parts in an enlarged scale for the sake of convenience in order to make the characteristics easier to understand, and the dimensional ratios of each component may not necessarily be the same as in reality. Furthermore, the materials, dimensions, etc. exemplified in the following description are merely examples, and the present invention is not necessarily limited to them, and may be appropriately modified and implemented within the scope of the present invention.

[0014] (First embodiment) First, as a first embodiment of the present invention, a laser measurement method and a laser measurement device 100 shown in, for example, FIGS. 1 to 6 will be described.

[0015] FIG. 2 is a plan view of the heat sink 1A for explaining the laser measurement method according to the first embodiment. FIG. 2 is a side view of the heat sink 1A. FIG. 3 is a plan view showing the dimensions of each part of adjacent pin fins 3 of the heat sink 1A. FIG. 4 is a schematic diagram showing the configuration of a laser measurement device 100. FIG. 5 is a side view showing a state in which the heat sink 1A is irradiated with laser light L. FIG. 6 is a plan view for explaining the spot diameter of the laser light L irradiated to the heat sink 1A.

[0016] (heat sink) The heat sink 1A, which is the object to be measured in this embodiment, comprises a plate-shaped base material (hereinafter referred to as the "substrate") 2 and a number of fins (hereinafter referred to as the "pin fins") 3 standing up in a pin-like (columnar) shape from one surface of the substrate 2, as shown in Figures 1 and 2.

[0017] The material of the heat sink 1A may be, for example, aluminum, aluminum alloy, copper, copper alloy, iron, iron alloy, etc. Also, the material of the heat sink 1A may be a clad material (composite material) made by bonding two or more kinds of metals. However, the material of the heat sink 1A is not limited to these metals and alloys, and various metal materials used as the material of the heat sink 1A may be used. The same material as the heat sink 1A may be used for the heat sink 1B described later.

[0018] The heat sink 1A has a structure in which a plurality of pin fins 3 are arranged in a staggered pattern at intervals in a first direction D1 and a second direction D2 that intersect with each other within the plane of the substrate 2.

[0019] The shape of the pin fins 3 is not particularly limited, and examples thereof include a circular shape, an elliptical shape, and a rectangular shape such as a square or a diamond shape in a plan view.

[0020] In this embodiment, cylindrical pin fins 3 having the same diameter and height are arranged in a staggered pattern at equal intervals in the first direction D1 and the second direction D2.

[0021] In this embodiment, as shown in FIG. 3, the third direction D3 is the direction in which the distance between two adjacent pin fins 3 among four adjacent pin fins 3 in the first direction D1 and the second direction D2 is greater than the distance in the first direction D1 and the distance in the second direction.

[0022] As shown in Figs. 2 and 3, when the center-to-center spacing in the first direction D1 and the center-to-center spacing in the second direction D2 are d, the height of the pin fins 3 is 3d to 4d.

[0023] In this case, the interval in the first direction D1 and the interval in the second direction D2 are sd in terms of the inner interval. The interval in the third direction D3 is 3×3 in terms of the center interval. 1 / 2 s, and the inner interval is 3 1 / 2 sd. Therefore, the interval in the third direction D3 is greater than the interval in the first direction D1 and the interval in the second direction D2.

[0024] The above dimensions are merely examples and are not necessarily limited to these dimensions. For example, the dimensions of each part can be appropriately changed depending on the tongue ratio, etc.

[0025] (Laser measurement device) As shown in FIG. 4, the laser measurement device 100 of this embodiment has a structure in which it comprises an optical unit 101 that irradiates laser light L onto one surface of the substrate 2 of the heat sink 1A, which is the object to be measured, a scanning unit 102 that scans the laser light L within the surface of the substrate 2, a light receiving unit 103 that receives the laser light L reflected and returned from the one surface of the substrate 2 of the heat sink 1A, and a calculation unit 104 that measures the heights of multiple pin fins 3 by calculation based on the measurement results of the laser light L received by the light receiving unit 103, and these are arranged inside the device body 105.

[0026] The optical unit 101 includes a light source such as a semiconductor laser and a focusing optical system such as a lens that focuses the laser light L emitted from the light source, and irradiates one surface of the substrate 2 of the heat sink 1A with the laser light L while focusing it.

[0027] Moreover, the optical section 101 is capable of adjusting the spot diameter of the laser light L irradiated onto one surface of the substrate 2 by moving the lens in the optical axis direction of the laser light L.

[0028] The scanning unit 102 scans the laser light L within the surface of the substrate 2 by moving either a stage 106 on which the heat sink 1A is placed or an apparatus body 105 relative to the other.

[0029] In the laser measurement device 100, it is also possible to rotate the stage 106 and to move the device body 105 relative to the stage 106 in a direction perpendicular to the plane of the substrate 2.

[0030] The light receiving unit 103 includes a light receiving element such as a CCD or a CMOS, receives the laser light L reflected and returned from one surface of the substrate 2 of the heat sink 1A, and transmits the received light signal to the calculation unit 104. In addition, the optical unit 101 transmits an output signal of the laser light L to the calculation unit 104.

[0031] Based on the light output signal from the optical unit 101 and the light receiving signal from the light receiving unit 103, the calculation unit 104 measures the difference in distance (height difference) between one surface (bottom surface) of the substrate 2 and the top surface of the pin fin 3, and calculates the heights of the multiple pin fins 3 from the measurement results.

[0032] The measurement method of the laser measurement device 100 is not particularly limited, and examples thereof include a triangulation method, and a time-of-flight method such as a phase difference distance method or a pulse propagation method.

[0033] (Laser measurement method) In the laser measurement method of this embodiment, as shown in FIG. 5, the above-mentioned laser measurement device 100 is used to irradiate one surface of the substrate 2 of the heat sink 1A, which is the object to be measured, with focused laser light L, and while scanning the laser light L within the surface of the substrate 2, the heights of multiple pin fins 3 are measured by measuring the laser light L reflected and returned from the one surface of the substrate 2 of the heat sink 1A.

[0034] That is, the height of the pin fins 3 can be measured by measuring the difference in distance (height difference) between one surface (bottom surface) of the substrate 2 and the top surface of the pin fin 3.

[0035] In this embodiment, the spot diameter of the laser light L is approximately 500 μm at the measurement point.

[0036] In the laser measurement method of this embodiment, the heights of the multiple pin fins 3 are measured while scanning the laser light L in a third direction D3 as indicated by an arrow A in FIG.

[0037] That is, the scanning direction of the laser light L is a third direction D3 in which the distance between two adjacent pin fins 3 among the four adjacent pin fins 3 in the first direction D1 and the second direction D2 described above is greater than the distance in the first direction D1 and the distance in the second direction D2.

[0038] This makes it possible to increase the distance over which the laser light L scans between adjacent pin fins 3, thereby stabilizing the measurement results.

[0039] Furthermore, as shown in FIG. 6, the spot diameter of the laser light L is preferably smaller than the diameter of the pin fin 3, and more preferably, is smaller than the gap G formed between three adjacent pin fins 3 out of the four adjacent pin fins 3 described above.

[0040] This makes it possible to avoid interference of the laser light L between adjacent pin fins 3, while by using laser light L with a larger spot diameter, it is possible to increase the tolerance for positional misalignment of the laser light L relative to the pin fin 3 when scanning with the laser light L.

[0041] Furthermore, when laser light L' is scanned in the first direction D1 as shown by arrow B in Figure 6, if the spot diameter of this laser light L' is not made smaller than the inner spacing between adjacent pin fins 3 in the first direction D1, the spot of laser light L' irradiated between adjacent pin fins 3 will interfere with the two pin fins 3.

[0042] In contrast, in the laser measurement method of the present embodiment, by scanning the laser light L in the third direction D3 described above, it is possible to accurately measure the heights of multiple pin fins 3 on the heat sink 1A while preventing the spot of the laser light L irradiated between adjacent pin fins 3 from interfering with the pin fins 3.

[0043] Second embodiment Next, as a second embodiment of the present invention, a laser measurement method shown in FIG. 7 will be described.

[0044] 7 is a plan view of the heat sink 1B for explaining the laser measurement method according to the second embodiment. In the following explanation, the explanation of the same parts as those in the heat sink 1A will be omitted and the same reference numerals will be used in the drawings.

[0045] (heat sink) The heat sink 1B, which is the object to be measured in this embodiment, has a structure in which a number of pin fins 3 are arranged in a lattice pattern with intervals provided in a first direction D1 and a second direction D2 that intersect with each other (orthogonal in this embodiment) within the plane of the substrate 2, as shown in FIG.

[0046] In this embodiment, cylindrical pin fins 3 having the same diameter and height are arranged in a lattice pattern at equal intervals in the first direction D1 and the second direction D2.

[0047] In this embodiment, the third direction D3 is the direction in which the distance between two adjacent pin fins 3 among the four pin fins 3 adjacent to each other in the first direction D1 and the second direction D2 is greater than the distance in the first direction D1 and the distance in the second direction.

[0048] In this embodiment, it is possible to select, as the third direction D3, two directions that intersect with each other (orthogonal to each other in this embodiment) in the plane of the substrate 2. That is, in these two directions, the intervals between adjacent pin fins 3 in the third direction D3 are equal.

[0049] (Laser measurement method) In the laser measurement method of this embodiment, as shown in FIG. 5, the above-mentioned laser measurement device 100 is used to irradiate one surface of the substrate 2 of the heat sink 1B, which is the object to be measured, with focused laser light L, and while scanning the laser light L within the surface of the substrate 2, the heights of multiple pin fins 3 are measured by measuring the laser light L reflected and returned from the one surface of the substrate 2 of the heat sink 1B.

[0050] In the laser measurement method of this embodiment, the heights of the multiple pin fins 3 are measured while scanning the laser light L in a third direction D3, as indicated by an arrow C in FIG.

[0051] That is, the scanning direction of the laser light L is a third direction D3 in which the distance between two adjacent pin fins 3 among the four adjacent pin fins 3 in the first direction D1 and the second direction D2 described above is greater than the distance in the first direction D1 and the distance in the second direction D2.

[0052] This makes it possible to increase the distance over which the laser light L scans between adjacent pin fins 3, thereby stabilizing the measurement results.

[0053] Furthermore, the spot diameter of the laser light L is preferably smaller than the diameter of the pin fin 3, and more preferably, is smaller than the gap G formed between three adjacent pin fins 3 out of the four adjacent pin fins 3 described above.

[0054] This makes it possible to avoid interference of the laser light L between adjacent pin fins 3, while by using laser light L with a larger spot diameter, it is possible to increase the tolerance for positional misalignment of the laser light L relative to the pin fin 3 when scanning with the laser light L.

[0055] In the laser measurement method of this embodiment, by scanning laser light L in the third direction D3 described above, it is possible to accurately measure the heights of multiple pin fins 3 on the heat sink 1B while preventing the spot of laser light L irradiated between adjacent pin fins 3 from interfering with the pin fins 3.

[0056] The present invention is not necessarily limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

[0057] For example, in the above embodiment, the heat sinks 1A and 1B are exemplified as the measurement object, but the measurement object is not necessarily limited to a heat sink, and may be any measurement object to which the laser measurement method of the present invention can be applied.

[0058] Furthermore, when the laser measurement device 100 is a V-shaped laser displacement meter in which thin linear or thin band-like laser light travels through different paths for incident light and reflected light, or a coaxial laser displacement meter in which incident light and reflected light travel through the same path, and in which the diameter of the laser light from the light-emitting part is wide and the diameter becomes narrower towards the tip, a particularly high effect can be obtained by applying the laser measurement method of the present invention. EXAMPLES

[0059] The effects of the present invention will be more clearly understood by the following examples. Note that the present invention is not limited to the following examples, and can be modified as appropriate without departing from the spirit and scope of the present invention.

[0060] In this embodiment, the cylindrical pin fins 3 having the same diameter and height as described above are arranged in a staggered pattern at equal intervals in the first direction D1 and the second direction D2 of the heat sink 1A. The heights of the pin fins 3 were measured while scanning the laser light L in the third direction D3 on the heat sink 1A, and the results are shown in the graph of Figure 8.

[0061] On the other hand, as a comparative example, the results of measuring the heights of the pin fins 3 while scanning the heat sink 1A with the laser light L' in the first direction D1 are shown in the graph of FIG.

[0062] It should be noted that the graphs in FIG. 8 and FIG. 9 are each shown with the scale of the graph being enlarged in the order of the upper, middle, and lower tiers.

[0063] As shown in Figures 8 and 9, when laser light L is scanned in the third direction D3, it is possible to measure the heights of multiple pin fins 3 on the heat sink 1A with greater accuracy than when laser light L' is scanned in the first direction D1. [Explanation of symbols]

[0064] Reference Signs List 1A, 1B... Heat sink (measurement object) 2... Substrate (base material) 3... Pin fin (pin) 100... Laser measurement device 101... Optical section 102... Scanning section 103... Light receiving section 104... Calculation section 105... Device body 106... Stage D1... First direction D2... Second direction D3... Third direction L... Laser light G... Gap

Claims

1. A laser measurement method for measuring heights of a plurality of pins by irradiating a laser beam onto a measurement object having a plurality of pins standing from one surface of a base material, the plurality of pins being arranged at intervals in a first direction and a second direction intersecting each other within the surface of the base material, and measuring the laser beam reflected and returning from the measurement object while scanning the laser beam within the surface of the base material, the method comprising: a laser measurement method for measuring heights of the pins while scanning the laser light in a third direction in which a distance between two adjacent pins among four pins adjacent to each other in the first direction and the second direction is greater than the distance in the first direction and the distance in the second direction.

2. 2. The laser measurement method according to claim 1, wherein the object to be measured is irradiated with the laser light while being focused.

3. 3. The laser measurement method according to claim 2, wherein a spot diameter of the laser light is set smaller than gaps formed between three adjacent pins among the four pins.

4. 2. The laser measurement method according to claim 1, wherein the plurality of pins are arranged in a staggered manner within a surface of the base material.

5. 2. The laser measurement method according to claim 1, wherein the plurality of pins are arranged in a lattice pattern within a surface of the base material.

6. 2. The laser measurement method according to claim 1, wherein the object to be measured is a heat sink.

7. A laser measurement device that measures heights of a plurality of pins by irradiating a laser beam onto a measurement object having a plurality of pins standing from one surface of a base material, the plurality of pins being arranged at intervals in a first direction and a second direction that intersect with each other within the surface of the base material, and measuring the laser beam reflected and returned from the measurement object while scanning the laser beam within the surface of the base material, an optical unit that irradiates the object to be measured with laser light; A scanning unit that scans the laser light within a surface of the base material; a light receiving unit that receives the laser light reflected and returned from the object to be measured; a calculation unit that calculates and measures heights of the pins based on a measurement result of the laser light received by the light receiving unit, the scanning unit scans the laser light in a third direction in which a distance between two adjacent pins of four pins adjacent to each other in the first direction and the second direction is greater than the distance in the first direction and the distance in the second direction.

8. 8. The laser measurement device according to claim 7, wherein the optical unit irradiates the object with the laser light while concentrating the laser light.

9. 9. The laser measurement device according to claim 8, wherein the optical unit sets a spot diameter of the laser light to be smaller than gaps formed between three adjacent pins among the four pins.

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