JP2008046952A - Image synthesis method and surface observation apparatus - Google Patents

Abstract

An image synthesizing method and a surface observation apparatus capable of quickly creating a synthesized image are provided.
An image synthesizing method is based on a focusing step (step S4) for focusing a photographing unit 2 on reference positions P ₀₁ and P ₀₂ of a punch 3, and coordinate data 22 representing a three-dimensional shape of the punch 3. , a moving step of moving the focal point of the imaging unit 2 in the imaging unit moving position P ₁₁ only moved following distance focal depth of 2, P ₁₂ (step S7), and the reference position P _01, P ₀₂ and the moving position P _11, a photographing step for photographing respectively (step S5) the surface of the punch 3 by the photographing unit 2 in the P _12, based on the area data 23 representing an image region G ₀₁ ~G ₁₂ are focused in the image 21 photographed by the photographing step Te, cut by selecting an image region G ₀₁ ~G ₁₂ cut steps (step S8), and the synthetic steps to create a composite image 50 by connecting the image region G ₀₁ ~G ₁₂ (step S9), and It is characterized by having.
[Selection] Figure 8

Description

  The present invention relates to an image synthesis method and a surface observation apparatus using the image synthesis method.

  Conventionally, it is known to use an all-focus method to photograph a subject (observed object) having partially different depths. According to the all-focus method, the shooting position is changed while moving the shooting unit by a minute distance in the depth direction of the subject, and an image of the subject taken at each shooting position is acquired. Then, by cutting out and synthesizing the in-focus portion from each acquired image, a synthesized image can be obtained in which any portion of the subject having a different depth is clearly displayed (for example, Patent Document 1). .

JP 2000-276121 A

  However, in the conventional technique, in order to extract a focused portion of a subject, it is necessary to perform complicated and enormous image processing using various filtering methods. For this reason, there has been a problem that the image processing unit is enlarged and it takes time until a composite image is obtained.

  In order to solve the above-described problems, an object of the present invention is to provide an image composition method and a surface observation apparatus that can quickly create a composite image.

  According to the image composition method of the present invention, the focus of the photographing unit is adjusted to the focus position of the photographing unit based on the focusing step for adjusting the focus of the photographing unit to the reference position of the observation object and the coordinate data representing the three-dimensional shape of the observation object The moving step for moving to a moving position moved by a distance less than the depth, the photographing step for photographing the surface of the observation object at the reference position and the moving position by the photographing unit, and the image photographed in the photographing step are in focus. The method includes a cutting step of selecting and cutting out the image region based on region data representing the image region, and a combining step of creating a composite image by joining the image regions.

  According to this image composition method, in order to create a composite image in which any part of an observation object having a three-dimensional shape is focused, first, the reference position, which is an easily focusable part of the observation object, is set. Adjust the focus of the shooting unit (focusing step). Then, the surface of the observation object at the reference position is imaged (imaging step). The captured image is a so-called in-focus image area in which the portion where the surface portion of the observation object located within the depth of focus of the imaging unit is in focus is in focus. The other surface portion located outside the focal depth is in a so-called out-of-focus blurred state. Next, the photographing unit is moved by a distance equal to or less than the focal depth of the photographing unit (moving step), and the surface of the observation object at the moved moving position is photographed (imaging step). As with the image at the reference position, the image captured at the moving position is a clear image area where the surface portion of the observed object located within the focal depth of the imaging unit is captured. After shooting, only a clear image area is selected and cut out from the images at the reference position and the moving position (cutting step). At this time, the image area is specified based on the coordinate data and area data of the observed object acquired in advance. Therefore, in the cutting step, it is only necessary to select and cut out the specified area, and there is no need to select and process the image area and the area other than the image area by filtering or the like. Next, the cut image areas are connected in order to create a composite image (compositing step). Even if the object to be observed has a three-dimensional shape that does not fall within the depth of focus of the image capturing unit, the photographable part of the object to be imaged can be obtained in a clear state. According to this method, it is possible to quickly create a composite image representing the surface state of an object to be observed whose shape is known.

  In this case, it is preferable to further include a display step of displaying the composite image on the display unit.

  According to this method, the method further includes a display step, and by displaying the composite image on the display unit, it is possible to quickly confirm the composite image created in real time. Therefore, when observing and checking the surface of a large number of objects to be observed, it is possible to check easily in a short time.

  In this case, it is preferable to further include a rotation step for rotating the object to be observed.

  According to this method, it further includes a rotation step, and by rotating the object to be observed, the surface of the object to be observed and the surface portion on the counter electrode side can be continuously imaged. This eliminates the need to change the position of the object to be observed and re-attach the object to the photographing unit, so that the entire object can be easily imaged.

  In this case, it is preferable that the movement step is executed a plurality of times.

  According to this method, by executing the movement step a plurality of times, even if the length of the movement direction in the movement step is an object to be observed that is several times longer than the focal depth of the imaging unit, The image area necessary for the composite image can be easily obtained.

  The surface observation apparatus of the present invention stores a placement unit for placing an observation object, an imaging unit for photographing the surface of the observation object, and coordinate data representing a three-dimensional shape of the observation object. Based on the storage unit, the moving unit that moves the imaging unit by a distance equal to or less than the focal depth of the imaging unit based on the coordinate data, and the area data that represents the focused image area of the image captured by the imaging unit, The image processing apparatus includes: a cutout unit that selects and cuts out an image region; and a combining unit that connects each of the image regions to create a combined image.

  According to this surface observation apparatus, a placement unit, a photographing unit, a storage unit, a moving unit, a cutting unit, and a composition for creating a composite image in which any part of an object having a three-dimensional shape is focused Has a part. First, when an object to be observed is placed on the placement unit, the photographing unit photographs the surface of the object to be observed. At this time, the photographed image is an image area in which a portion obtained by photographing the surface portion of the observation object located within the focal depth of the photographing unit is in focus, a so-called focused, clear state, The other surface portion located outside the focal depth of the photographing unit is in a so-called out-of-focus blurred state. Next, the moving unit moves the photographing unit by a distance equal to or less than the focal depth of the photographing unit. The photographing unit photographs the surface of the observation object at the moved position. In the image captured at the moved position, a portion where the surface portion of the observation object located within the focal depth of the imaging unit is captured is a clear image region. After shooting, the cutout unit selects and cuts out only a clear image area from each image. At this time, the image area is specified based on the coordinate data and area data of the observation object acquired in advance, and the cutout unit may select the specified area. Therefore, in the cutting step, there is no need to process the image area and the area other than the image area by filtering or the like and select based on the processing result. Next, the synthesized image is created by sequentially joining the image areas cut by the synthesis unit. Even if the object to be observed has a three-dimensional shape that does not fall within the depth of focus of the image capturing unit, the photographable part of the object to be imaged can be obtained in a clear state. According to this surface observation apparatus, it is possible to quickly create a composite image representing the surface state of an object to be observed whose shape is known.

  In this case, it is preferable to further include a display unit that displays the composite image.

  According to this configuration, the surface observation apparatus further includes the display unit, and by displaying the composite image on the display unit, it is possible to confirm the composite image that has been quickly created in real time. Therefore, when observing and checking a large number of objects to be observed, it is possible to check easily in a short time.

  In this case, it is preferable that the object to be observed is attached to the rotating part of the fixing jig placed on the placing part.

  According to this configuration, the surface observation device can rotate the object to be observed, and can image the surface part on the opposite side of the object to be imaged. Accordingly, it is not necessary to reattach the object to be observed with respect to the photographing unit, and it is possible to easily photograph the entire periphery of the object to be observed.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, embodiments of the invention will be described with reference to the drawings. In the embodiment, a case will be described in which the surface state of a punch for punching is photographed with a surface observation device and the presence or absence of scratches is observed and checked. The confirmation of the surface state is performed by a composite image created based on the photographed image.
(Embodiment)

  FIG. 1 is a schematic diagram showing the configuration of the surface observation apparatus of the present invention. The surface observation apparatus 1 includes an imaging unit 2, an X-axis stage (mounting unit) 5 on which a punch 3 that is an object to be observed is mounted via a fixing jig 4, and is movable in the X-axis direction, and a Y-axis direction. And a Z-axis stage (moving unit) 7 for moving the photographing unit 2 in the Z-axis direction. The photographing unit 2 includes a CCD camera 2 a for photographing the punch 3 and a camera lens 2 b, and the fixing jig 4 includes a rotating unit 4 a that rotates the punch 3. And the surface observation apparatus 1 is further provided with the control part 10, and while the control part 10 controls the imaging | photography part 2, the X-axis stage 5, the Y-axis stage 6, and the Z-axis stage 7, various data and instruction | indications The input unit 20 for performing the above-described input and the display unit 25 for displaying the composite image of the photographed punch 3 and the like are controlled.

  Next, FIG. 2 is a block diagram illustrating a configuration of a control unit of the surface observation apparatus. The control unit 10 includes a CPU (Central Processing Unit) 11, a ROM (Read Only Memory) 12, and a RAM (Random Access Memory) 13. The ROM 12 is a readable / writable nonvolatile memory having an image composition program 18 for creating a composite image, and the RAM 13 is an image 21 of the punch 3 photographed by the photographing unit 2 and data inputted from the input unit 20. Temporarily, coordinate data 22 representing the three-dimensional data of the punch 3, area data 23 obtained by previously calculating an in-focus image area in the image 21 of the punch 3, and a composite image 50 obtained by synthesizing the image areas. It is memory as a memory | storage part memorize | stored in. Furthermore, the control unit 10 controls the imaging unit 2, the drive control unit 15 that controls the X-axis stage 5, the Y-axis stage 6, and the Z-axis stage 7, and the display that controls the display unit 25. It has the control part 16 and the input control part 17 which controls the input part 20. FIG.

  In the control unit 10 having such a configuration, the CPU 11 refers to the region data 23 based on the image composition program 18 in the ROM 12 and combines the cut-out unit that cuts out the image region from the image 21 and the cut-out image region. While functioning as a synthesis unit, the entire control unit 10 is controlled based on firmware (not shown) of the ROM 12. Then, the coordinate data 22 of the punch 3 has a three-dimensional shape in a plurality of images 21 obtained by shooting a plurality of times while changing the focal position with respect to the punch 3 in accordance with the focal depth of the photographing unit 2. This is to obtain a clear image area on the surface of the punch 3 without omission. Further, the area data 23 is obtained by calculating in advance an image area that is a clear and focused part in each image 21. Details of the coordinate data 22 and the area data 23 will be described later with reference to FIG.

  Here, the punch 3 of the object to be observed will be briefly described. 3A is a plan view showing an appearance of the punch, FIG. 3B is a cross-sectional view showing press working of the nozzle to the nozzle plate, and FIG. 3C is a cross-sectional view showing discharge of droplets from the nozzle. is there. The punch 3 is a tool for processing a nozzle for discharging various material liquids in a droplet state in an ink jet apparatus, and has a diameter d and a length e as shown in FIG. A punching portion 3a having a columnar shape, a holding portion 3c having a diameter larger than d for attaching the punch 3 to the press, and a substantially conical shape provided between the punching portion 3a and the holding portion 3c. Forging part 3b. In this case, the diameter d is 20 μm and the length e is 80 μm.

  The punch 3 is attached to a press machine, and the nozzle 31 is processed into a nozzle plate 30 having a thickness of 80 μm, as shown in FIG. First, the position where the nozzle 31 of the nozzle plate 30 is processed is aligned with the punch 3. Then, the press machine is operated and the nozzle plate 30 is punched in a circular shape by the punching portion 3 a of the punch 3. Following the punched portion 3 a, a conical portion is formed by the forged portion 3 b of the punch 3. Thereby, the cross-sectional shape of the nozzle 31 is processed into a funnel shape. The burrs and the like generated by the processing of the punching portion 3a are removed by grinding.

  The nozzle plate 30 processed in this way is attached to an ink jet apparatus, and the material liquid 40 is stored on the side of the nozzle 31 formed on the nozzle plate 30 that is opened in a funnel shape, as shown in FIG. ing. When the pressure W is applied to the material liquid 40, the material liquid 40 is pushed out from the nozzle 31 and discharged as droplets 41. At this time, in order to eject the prescribed amount of droplets 41 in a predetermined direction, it is required to ensure the dimensional accuracy of the nozzle 31 and to have surface accuracy without scratches on the surface. For this purpose, it is necessary to ensure the dimensional accuracy of the punch 3 for processing the nozzle 31 and the surface accuracy of the punch surface. The surface observing apparatus 1 is used for observing the surface of the punch 3 for scratches, cracks, foreign matter, distortion, etc., and for checking to ensure surface accuracy.

Next, a method for observing and checking the surface accuracy of the punch 3 by cutting out a focused image region from an image obtained by photographing the surface of the punch 3 by the surface observation device 1 and creating a composite image will be described. FIG. 4 is a schematic diagram showing an image area of each part of the punch surface imaged by the imaging unit. FIG. 5A is a plan view showing an image region farthest from the photographing unit, and FIG. 5B is a plan view showing an image region adjacent to the image region farthest from the photographing unit. FIG. 6C is a plan view showing an image area adjacent to the most recent image area from the imaging section, and FIG. 6D is a plan view showing the most recent image area from the imaging section. 4 is a view of the circular surfaces of the photographing unit 2 and the punching unit 3a of the punch 3 shown in FIG. 1 as viewed along the Y-axis direction. The photographing unit 2 captures the photographing unit 2 in the drawing. Image regions G _{01 to} G ₃₁ are schematically shown. In this case, the photographing unit 2 can photograph the half circumferential surface of the punch 3 on the side of the photographing unit 2 as the image 21. 5 and 6 show details of the image regions G _{01 to} G ₃₁ shown in FIG.

As shown in FIG. 4, the surface observation apparatus 1 has a total of 4 at each of the photographing positions Z _{0 to} Z ₃ located at intervals of the movement distance h in order to photograph the half circumferential surface of the punched portion 3a clearly and without omission. Take one shot. In this case, the moving distance h is set to the same value as the focal depth of the photographing unit 2. First, in order to photograph the punch 3 at the photographing position Z ₀ , first, the photographing unit 2 is moved by the Z-axis stage 7 linked with the autofocus function, and the edge (outer peripheral position) of the punch 3 that is easy to focus. The photographing unit 2 is focused on the reference positions P ₀₁ and P ₀₂ . Further, in consideration of the depth of focus of the imaging unit 2, the imaging unit 2 is moved so that the farthest part from the imaging unit 2 with the focal depth matches the reference positions _P01 and _P02 . That is, by separating the photographing unit 2 from the punch 3 by h / 2, the area of the half circumferential surface of the punch 3 that can be clearly photographed within the focal depth of the photographing unit 2 at the reference positions P ₀₁ and P ₀₂ . It is possible to increase.

The imaging surface F ₀₁ between the reference position P ₀₁ and the movement position P ₁₁ that is separated from the reference position P ₀₁ by the movement distance h in the Z-axis direction is an area on the half circumferential surface of the punch 3 that can be clearly photographed. This is the imaging plane F ₀₂ between the reference position P ₀₂ and the movement position P ₁₂ that is separated from the reference position P ₀₂ by a movement distance h in the Z-axis direction. The depth of focus of the photographing unit 2 is between the reference position P ₀₁ and the movement position P ₁₁ and between the reference position P ₀₂ and the movement position P ₁₂ . The imaging plane F ₀₁ within the depth of focus is a clear image area G ₀₁ having an image area width L ₀₁ in the image 21 taken by the imaging unit 2. Similarly, the imaging plane F ₀₂ within the focal depth is a clear image area G ₀₂ having an image area width L ₀₂ in the image 21 captured by the imaging unit 2. The image 21 photographed at the photographing position Z ₀ is so-called out-of-focus, in which portions corresponding to the image regions G ₀₁ and G ₀₂ are clearly photographed and the other photographing surface portions are unclear.

As shown in FIG. 5A, the punch 3 photographed by the photographing unit 2 at the photographing position Z ₀ is a clear image in which the photographing surface F ₀₁ of the punching part 3a forms a rectangle having an image area width L ₀₁ and a length e. The image area G ₀₁ is stored in the RAM 13 as an image 21 including another photographing surface. At the same time, the photographing surface F ₀₂ of the punching unit 3 a is also stored in the RAM 13 as a clear image region G ₀₂ having a rectangular shape with an image region width L ₀₂ and a length e.

After the photographing at the photographing position Z ₀ is finished, the photographing unit 2 is moved in the photographing position Z ₁ direction by the movement distance h by the Z-axis stage. At the photographing position Z ₁ , the photographing surface F ₁₁ between the moving position P ₁₁ and the moving position P ₂₁ separated from the moving position P ₁₁ by the moving distance h in the Z-axis direction, and the moving position P ₁₂ and the moving position P _12. The imaging plane F ₁₂ between the imaging unit 2 and the movement position P ₂₂ that is separated from the imaging unit 2 by the movement distance h in the Z-axis direction is within the focal depth of the imaging unit 2. Therefore, the imaging plane F ₁₁ is a clear image area G ₁₁ having an image area width L ₁₁ in the image 21 captured by the imaging section 2. Similarly, the imaging plane F ₁₂ within the focal depth is the imaging area F _11. in the image 21 taken by 2, a clear image area G ₁₂ having an image area width L _12. In the image 21 photographed at the photographing position Z ₁ , the portions corresponding to the image regions G ₁₁ and G ₁₂ are clear, and the portions on the other photographing surfaces are unclear.

As shown in FIG. 5B, the punch 3 photographed by the photographing unit 2 at the photographing position Z ₁ has a photographing surface F ₁₁ of the punching unit 3a having a rectangular shape with an image region width L ₁₁ and a length e. as clear image region G ₁₁ is stored in the RAM 13. At the same time, imaging surface F ₁₂ of the punch section 3a is also a clear image area G ₁₂ forming a rectangular image area width L ₁₂ and length e is stored in the RAM 13.

After the photographing at the photographing position Z ₁ is completed, the photographing unit 2 is moved in the direction of the photographing position Z ₂ by the movement distance h by the Z-axis stage. At the photographing position Z ₂ , the photographing surface F ₂₁ between the moving position P ₂₁ and the moving position P ₃₁ separated from the moving position P ₂₁ by the moving distance h in the Z-axis direction, and the moving position P ₂₂ and the moving position P _22. The imaging plane F ₂₂ between the imaging unit 2 and the moving position P ₃₂ that is separated by the moving distance h in the Z-axis direction is within the focal depth of the imaging unit 2. Accordingly, the imaging surface F ₂₁ is a clear image region G ₂₁ having an image region width L ₂₁ in the image 21 captured by the imaging unit 2. Similarly, the imaging surface F ₂₂ within the depth of focus is the imaging surface F _22. 2 is a clear image area G ₂₂ having an image area width L ₂₂ . In the image 21 photographed at the photographing position Z ₂ , the portions corresponding to the image regions G ₂₁ and G ₂₂ are clear, and the portions on the other photographing surfaces are unclear.

Photographing position Z ₂ punch 3 Oite photographing unit 2 is taken, as shown in FIG. 6 (c), imaging surface F ₂₁ of the punch section 3a is formed a rectangular image area width L ₂₁ and length e as clear image region G ₂₁ is stored in the RAM 13. At the same time, the photographing surface F ₂₂ of the punched portion 3a is also stored in the RAM 13 as a clear image region G ₂₂ having a rectangular shape with an image region width L ₂₂ and a length e.

Then, after the photographing at the photographing position Z ₂ is completed, the photographing unit 2 is moved by the movement distance h in the photographing position Z ₃ direction by the Z-axis stage. In this case, at the shooting position Z ₃ , the area of the half circumference of the punch 3 between the movement position P ₃₁ and the movement position P ₃₂ is within the focal depth of the imaging section 2, and the area of the half circumference of the punch 3 is moved. This is the imaging plane F ₃₁ between the position P ₃₁ and the movement position P ₃₂ . Accordingly, the imaging surface F ₃₁ is a clear image region G ₃₁ having an image region width L ₃₁ in the image 21 captured by the imaging unit 2, and the other imaging surface portions are unclear.

In the punch 3 photographed by the photographing unit 2 at the photographing position Z ₃ , as shown in FIG. 6D, the photographing surface F ₃₁ of the punching unit 3 a forms a rectangle with an image region width L ₃₁ and a length e. as clear image region G ₃₁ is stored in the RAM 13. As described above, the four images 21 obtained by the four shootings include the image regions G _{01 to} G _{31 in} which the half circumferential surface of the punch 3 is clearly captured.

Here, a description about setting imaging position Z ₀ to Z ₃ for photographing the punch 3. In order to photograph the punch 3 with the photographing unit 2, the surface observation device 1 takes in coordinate data 22 and region data 23 from the input unit and stores them in the RAM 13. In this case, since the diameter d of the punch 3 is 20 μm and the depth of focus of the photographing unit 2 is 3 μm, the photographing unit is required to photograph the half circumferential surface of the punch 3 having a radius r of 10 μm shown in FIG. When the moving distance h of 2 is 3 μm, four shootings are required at the shooting positions Z _{0 to} Z ₃ , and the shooting position and the number of shootings can be set from the diameter d of the punch 3 and the focal depth of the shooting unit 2. is there. Since the punch 3 of the object to be observed has a known shape, the coordinate data 22 includes a reference position P ₀₁ and a reference position P ₀₂ that are respectively located at the photographing positions Z _{0 to} Z ₃ on the half circumferential surface of the punching portion 3a. It has the coordinate values of the movement position P ₁₁ to the movement position P ₃₂ and represents the three-dimensional shape of the punch 3.

Further, the area data 23 is an image obtained by photographing a half circumferential surface of the punching unit 3 a located within the focal depth of the photographing unit 2 in the image 21 photographed at each of the photographing positions Z _{0 to} Z ₃ based on the coordinate data 22. The areas G _{01 to} G ₃₁ are specified by calculation in advance. Referring to region data 23, area of the image 21 throat is easy determination whether the image region G ₀₁ ~G _31.

Note that if the depth of focus of the photographing unit 2 is increased, the range in which clear photographing can be performed becomes wider than the distance 3 μm between the photographing positions Z ₀ and Z _1, and the number of photographing can be reduced, but the degradation of the image 21 occurs. This makes it difficult to check the surface accuracy. Therefore, in order to observe and check the surface accuracy of the punch 3, it is desirable to obtain a more precise image by reducing the depth of focus to, for example, about 1 μm, although the number of times of photographing increases.

Next, the creation of the composite image 50 will be briefly described. FIG. 7 is a plan view showing a composite image. The composite image 50 clearly represents any part of the half circumferential surface of the punch 3 as one image. The composite image 50 is created by the CPU 11 in accordance with the image composition program in the ROM 12 based on each image 21 photographed at the photographing positions Z _{0 to} Z ₃ and stored in the RAM 13. First, the image regions G _{01 to} G ₃₁ are cut out from the image 21, and then the cut image regions G _{01 to} G ₃₁ are connected in order to create a composite image 50 as shown in FIG. With this composite image 50, the surface state of the three-dimensional punch 3 can be precisely observed and checked.

  Hereinafter, an image composition method for creating the composite image 50 by the surface observation apparatus 1 will be described with reference to a flowchart. FIG. 8 is a flowchart for creating a composite image. The flowchart shows the steps executed by the control unit 10 of the surface observation apparatus 1.

  First, in step S1, it is determined whether or not the punch 3 is set on the fixing jig 4 and an instruction to start observation is received. An instruction to start observation is input from the input unit 20. If an instruction has not been received, the instruction is waited in step S1, while if it has been received, the process proceeds to step S2.

  In step S2, the movement of the X-axis stage 5 and the Y-axis stage 6 is instructed based on the coordinate data 22 of the punch 3, and the punch 3 is moved to a position where photographing can be performed. After the movement instruction, the process proceeds to step S3.

  In step S3, it is determined whether or not the punch 3 has entered the field of view of the CCD camera 2a. The determination is made by the imaging control unit 14 confirming the image from the imaging unit 2. If the punch 3 is out of the field of view, the process returns to step S2, while if it is within the field of view, the process proceeds to step S4.

  In step S4, the Z-axis stage 7 is moved to determine whether or not the CCD camera 2a is focused on the edge of the punch 3. This determination is made by the imaging control unit 14 confirming the image from the imaging unit 2. In this case, as described above, the farthest portion from the CCD camera 2a within the focal depth matches the edge of the punch 3. Step S4 corresponds to the focusing step. If it is not in focus, the adjustment is continued by moving the Z-axis stage 7 in step S4. On the other hand, if it is in focus, the process proceeds to step S5.

  In step S5, the surface of the punch 3 is photographed by the CCD camera 2a, and the photographed image 21 is stored in the RAM 13. Step S5 corresponds to a photographing step. After shooting, the process proceeds to step S6.

  In step S6, it is determined whether or not four times of photographing have been executed. The determination is made by the CPU 11 counting the number of shooting commands that the shooting control unit 14 has instructed the shooting unit 2. If it is less than four times, the process proceeds to step S7, and if it has reached four times, the process proceeds to step S8.

  If it is less than four times, in step S7, the Z-axis stage 7 is moved by the moving distance h. Step S7 corresponds to a moving step. After the movement, the process returns to step S5.

If the number has reached four, each captured image 21 is cut out based on the area data 23 in step S8. The portions to be cut out are image regions G _{01 to} G ₃₁ of each image 21. In this case, since each of the image areas G _{01 to} G ₃₁ is specified by the coordinate value by the area data 23, an operation such as a filter process is not necessary and can be easily cut out. This process is executed by the CPU 11 functioning as a cutting unit in accordance with the image composition program 18 in the ROM 12. Step S8 corresponds to a cutting step. After cutting, the process proceeds to step S9.

In step S9, the image region G ₀₁ ~G ₃₁ taken as shown in FIG. 7, by joining in order to create a composite image 50. This process is executed by the CPU 11 functioning as a synthesis unit in accordance with the image synthesis program 18 in the ROM 12. Step S9 corresponds to a synthesis step. After creation, the process proceeds to step S10.

  In step S <b> 10, the composite image 50 is displayed on the display unit 25. By displaying on the display unit 25, the surface accuracy of the punch 3 can be observed and checked in real time. Step S10 corresponds to a display step. The composite image 50 is created through the above steps.

  After step S10, if the rotating part 4a of the fixing jig 4 is operated and the punch 3 is rotated 180 degrees as a rotation step, the opposite of the punch 3 is performed again by executing the steps S1 to S10. It is possible to continue to shoot the half circumference surface. Thus, the entire circumference of the punched portion 3a of the punch 3 can be photographed without omission only by the minimum rotational movement of the punch 3.

  The specific embodiments related to the image composition method by the surface observation apparatus 1 have been described above. The effects of the embodiment will be collectively described below.

  (1) The punch 3 has a three-dimensional shape that deviates from the depth of focus of the photographing unit 2 by an image composition method in which the shape of the punch 3 of the object to be observed is specified in advance by the coordinate data 22 and the area data 23. However, any portion of the punch 3 that can be photographed is obtained as a single composite image 50 in a clear state. According to this method, it is possible to quickly create the composite image 50 that displays the surface state of the punch 3.

(2) Since the composite image 50 can be created and the surface state of the punch 3 can be checked by one composite image, there is no need to individually check each image 21 photographed at the photographing positions Z _{0 to} Z ₃ . Efficient check.

  (3) Since the complicated filtering process that is normally performed is unnecessary in creating the composite image 50, there is no practical problem even if the control unit 10 has a low processing speed to perform the filtering process. Image composition processing can be executed.

  (4) By displaying the composite image 50 on the display unit 25, the composite image 50 created quickly can be confirmed in real time. Therefore, when observing and checking the surface of a large number of punches 3, it can be easily performed in a short time.

  Further, the present invention is not limited to the above-described embodiment, and the same effects as those of the embodiment can be obtained even in the form of the following modification.

(Modification 1) The distance between the reference position P ₀₁ and the movement position P ₁₁ , the distance between the movement position P ₁₁ and the movement position P _21, and the distance between the movement position P ₂₁ and the movement position P ₃₁ are expressed by the depth of focus. Instead of the same moving distance h, it may be equal to or shorter than the moving distance h. Further, there are overlapping portions of the image regions G _{01 to} G ₃₁ , which may be different distances that are less than or equal to the moving distance h, and the calculation of the region data 23 becomes complicated, but the composite image 50 is the same as in the embodiment. Can be created.

(Modification 2) step S4, the focus of the CCD camera 2a may remain combined with the reference position P ₀₁ and P _02, it may not be performed adjustment corresponding to the depth of focus. Although the image area widths L ₀₁ and L _{02 of the} image areas G ₀₁ and G ₀₂ are reduced, a composite image can be created.

  (Modification 3) The coordinate data 22 and the area data 23 may be stored in the ROM 12 instead of the RAM 13. The ROM 12 is a non-volatile memory and does not require an operation of reading from the input unit every time the punch 3 is observed.

  (Modification 4) The Z-axis stage 7 may move the X-axis stage 5 which is a mounting part instead of the structure which moves the imaging | photography part 2. FIG. The photographing unit 2 is fixed, and a more stable photographing state can be maintained.

  (Modification 5) The stage on which the punch 3 is placed via the fixing jig 4 is not limited to the X-axis stage 5, and the Y-axis stage 6 may be the placement part. It is possible to increase the degree of freedom of the placement unit configuration of the surface observation device 1.

  (Modification 6) The rotating part 4 a of the fixing jig 4 may be configured to rotate under the control of the control part 10. The operation is efficient when observing a large number of punches 3 continuously.

  (Modification 7) In step S10, the composite image 50 may be displayed not only on the display unit 25 but also by a printer. It is possible to leave an observation check record of the punch 3.

The schematic diagram which shows the structure of the surface observation apparatus of this invention. The block diagram which shows the structure of the control part of a surface observation apparatus. (A) Top view which shows the external appearance of a punch, (b) Sectional drawing which shows the press work of the nozzle to a nozzle plate, (c) Sectional drawing which shows discharge of the droplet from a nozzle. The schematic diagram which shows the image area | region of each part of the punch surface image | photographed by the imaging | photography part. (A) The top view which shows the image area of the furthest part from the imaging | photography part, (b) The top view which shows the image area adjacent to the image area of the furthest part from the imaging | photography part. (C) The top view which shows the image area adjacent to the image area of the nearest part from an imaging | photography part, (d) The top view which shows the image area of the nearest part from an imaging | photography part. The top view which shows a synthesized image. FIG. 5 is a flowchart for creating a composite image.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Surface observation apparatus, 2 ... Imaging | photography part, 2a ... CCD camera, 2b ... Camera lens, 3 ... Punch as observation object, 4 ... Fixing jig, 5 ... X-axis stage as mounting part, 6 ... Y Axis stage, 7... Z-axis stage as moving unit, 10... Control unit, 11... CPU as cutting unit and combining unit, 12... ROM, 13. Control unit, 18 ... image composition program, 21 ... image, 22 ... coordinate data, 23 ... area data, 30 ... nozzle plate, 31 ... nozzle, 50 ... composite image, h ... moving distance, _P01 , _P02 ... reference position , P _{03 to} P ₃₂ ... Movement position, F _{01 to} F ₃₁ .. Imaging plane, G _{01 to} G ₃₁ ... Image area, L _{01 to} L ₃₁ ... Image area width, Z _{0 to} Z ₃ .

Claims (7)

A focusing step for focusing the imaging unit on the reference position of the object to be observed;
Based on the coordinate data representing the three-dimensional shape of the object to be observed, a movement step of moving the focal point of the imaging unit to a movement position that has been moved by a distance equal to or less than the focal depth of the imaging unit;
Photographing steps for photographing the surface of the observation object at the reference position and the moving position by the photographing unit, respectively.
A cutting step of selecting and cutting out the image area based on area data representing an image area in focus of the image taken in the shooting step;
And a synthesis step of creating a synthesized image by joining the image areas. The image composition method according to claim 1,
An image synthesizing method further comprising a display step of displaying the synthesized image on a display unit. The image composition method according to claim 1, further comprising a rotation step of rotating the object to be observed. In the image composition method according to any one of claims 1 to 3,
The image synthesizing method, wherein the moving step is executed a plurality of times. A placement unit for placing an object to be observed;
An imaging unit for imaging the surface of the object to be observed;
A storage unit storing coordinate data representing a three-dimensional shape of the object to be observed;
A moving unit that moves the imaging unit by a distance equal to or less than the focal depth of the imaging unit based on the coordinate data;
A cutout unit that selects and cuts out the image region based on region data representing an image region in focus of the image taken by the photographing unit;
A surface observing apparatus comprising: a combining unit that connects the image regions to create a combined image. In the surface observation apparatus according to claim 5,
A surface observation apparatus further comprising a display unit for displaying the composite image. The surface observation apparatus according to claim 5 or 6,
The surface observation apparatus according to claim 1, wherein the object to be observed is attached to a rotating part of a fixing jig placed on the placing part.

Images