JP2009002789A - Portable measuring device, and measuring method using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a small-sized, inexpensive and portable measuring device capable of acquiring easily a focused image. <P>SOLUTION: This portable measuring device capable of measuring a measuring object, in a state of being held by a user's hand, is equipped with an imaging means for acquiring a photographed image by photographing the measuring object, a recording means for recording a photographed image group acquired by continuously photographing during a fixed period by the imaging means; an instruction input means for performing instruction input, in order to make a recording operation of the photographed image group start in the fixed period, and a selection means for selecting a photographed image, having the highest focusing degree from among a plurality of photographed images recorded in the recording means. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a portable measuring instrument capable of measuring an object to be measured by hand, and more particularly to a portable measuring instrument that captures an image of the object to be measured and obtains a focused image, and a measurement method using the same. .

Conventionally, for example, a three-dimensional measuring instrument that measures a three-dimensional shape of an object to be measured such as a medical disease shape measuring instrument or an endoscope scale in a non-contact manner (see Patent Document 1), etc. ) A portable measuring instrument (handy type measuring instrument) capable of measuring an object to be measured is known. At the time of measurement by the portable measuring instrument, an object to be measured is imaged and an image (in-focus image) in focus is obtained. There is a fixed focus (pan focus) method as a method of adjusting the focus at the time of imaging.
Japanese Patent Laid-Open No. 4-12724 JP-A-9-325018

  However, since the focus position is fixed in the above fixed focus method, it is necessary to adjust the focus by moving the portable measuring instrument by hand, that is, by moving the object far or away from the object to be measured. It is not easy to obtain a focused image with this distance (focal length) fixed. Further, even if the focus is variable instead of such a fixed focus, in the case of manual focus, the distance from the object to be measured cannot be fixed and the focusing function itself has no meaning. On the other hand, in the case of the autofocus (AF) method (see Patent Document 2), the correct focus position can be easily found, but the portable measuring instrument has only the AF function (AF mechanism). This leads to an increase in size (upsizing) and cost.

  The present invention has been made in view of the above circumstances, and provides a portable measuring instrument that can easily acquire a focused image in measurement even if it is portable, and a measurement method using the portable measuring instrument. Objective.

  A portable measuring instrument according to the present invention is a portable measuring instrument capable of measuring an object to be measured while being held in a hand of a user, and obtains a photographed image by photographing the object to be measured. Means, recording means for recording a group of photographed images obtained by continuous photographing by the imaging means for a predetermined period, and instruction input for instructing to start a recording operation of the photographed image group for the predetermined period And a selection means for selecting a photographed image with the highest degree of focus from a plurality of photographed images recorded in the recording means.

  According to the above configuration, in the portable measuring instrument capable of measuring the object to be measured while being held in the hand, the object to be measured is captured by the imaging unit to obtain a captured image, and the recording unit A group of captured images obtained by continuously capturing images for a predetermined period by the imaging unit is recorded. Then, an instruction input for starting the recording operation of the photographed image group for a certain period is performed by the instruction input unit, and a photographed image with the highest degree of focus is selected from the plurality of photographed images recorded in the recording unit by the selection unit. Is selected.

  In this way, recording of a captured image is started in response to a user's operation, and a captured image group obtained by continuously capturing images for a certain period is recorded, and the recorded captured image group is selected from the recorded captured image group. Since the photographed image with the highest degree of focus is selected, for example, the user holds the portable measuring instrument to the approximate in-focus position with his hand, and shoots for a certain period while moving the vicinity of the in-focus position. By recording the image, a group of captured images including the captured image at the in-focus position is recorded, and from this captured image group, processing by a selection unit (processing for selecting a captured image with the highest degree of focus) is automatically performed. A focused image can be acquired. Therefore, even in such a portable type, the user does not need to accurately adjust the focus position with respect to the object to be measured, and so-called roughly photographing the vicinity of the focus position (recording a plurality of image frames continuously). It is possible to easily obtain a focused image.

  Moreover, in the said structure, you may further provide the display means comprised so that the monitor image of the picked-up image by the said imaging means was possible (Claim 2).

  According to this, since the display unit configured to be able to monitor and display the captured image by the imaging unit is further provided, the user can easily approximate the in-focus position while viewing the captured image of the object to be measured on the monitor display of the display unit. Can be found. That is, the focused image can be surely included in the captured image group, and as a result, the focused image can be acquired more easily in the measurement by the portable measuring instrument.

  Further, in the above configuration, a focus detection unit that detects whether or not the object to be measured is focused based on the captured image, and when the focus is detected by the focus detection unit, It may further comprise recording control means for performing control for stopping the recording operation by the recording means.

  According to this, the focus detection unit detects whether or not the object to be measured is focused based on the photographed image, and the focus is detected by the focus detection unit by the recording control unit. Then, control for stopping the recording operation by the recording means is performed, so that a photographed image (when the focus degree is the most focused) is detected in the photographed image group obtained by photographing the vicinity of the in-focus position roughly. It is possible to more easily and reliably include an image that is assumed to be a high-in-focus image, which is not necessarily a required focused image.

  Further, in the above configuration, the recording control unit performs control to cause the recording unit to record a captured image in a cyclic manner, and the recording control unit starts from the time when the in-focus is detected by the in-focus detection unit. Control may be performed to stop the recording operation after the photographed image is cyclically recorded by a predetermined capacity in the recording capacity of the means (claim 4).

  According to this, the recording control means performs control to cause the recording means to record the photographed image cyclically, and the recording means from the time point when the focus detection means detects the in-focus by the recording control means. Since the recorded image is cyclically recorded by a predetermined capacity in the recording capacity of the recording medium, the recording operation is controlled so that the focus is detected by the focus detection means in the recorded photographed image group. A photographed image (a front pin image and a rear pin image) at a position before and after the photographed image (focused position) is included in addition to the photographed image (image assumed to be a focused image as described above). be able to. For this reason, it becomes possible to acquire a focused image more accurately by selecting a captured image with the highest degree of focus from these captured image groups.

  In the above configuration, the focus detection unit may detect whether or not the focus is achieved based on the contrast of the captured image.

  According to this, since it is detected by the focus detection means based on the contrast of the photographed image, it is possible to easily perform the focus detection by a simple method.

  Further, in the above configuration, the projector further includes a projecting unit that projects the cross-shaped slit light onto the object to be measured, and the focus detection unit is configured such that the intersection of the cross-shaped slit light coincides with a predetermined position of the object to be measured. It is also possible to detect whether or not the in-focus state is obtained by discriminating the above.

  According to this, the cross-shaped slit light is projected onto the object to be measured by the projecting means, and the focus detection means determines the degree of coincidence of the intersection of the cross-shaped slit light with the predetermined position of the object to be measured. Since it is detected whether or not it is in focus, for example, when the portable measuring instrument is a three-dimensional measuring instrument and projects a cross-shaped slit light onto the object to be measured in order to perform the three-dimensional measurement, this Focus detection can be easily performed using existing projection means (at low cost).

  In the above-described configuration, the recording control unit may start the recording operation of the photographed image by the recording unit in accordance with the instruction input from the instruction input unit until the recording operation is stopped in accordance with the instruction input by the instruction input unit. Control may be performed to cause the recording means to record a photographed image during the predetermined period.

  According to this, the recording control means starts a recording image recording operation by the recording means in accordance with the instruction input by the instruction input means, and then stops for a certain period of time until the recording operation is stopped by the instruction input by the instruction input means. In the meantime, the recording unit is controlled to record the photographed image. That is, since the photographed image is recorded only while the user presses the instruction input means, for example, the input button (a certain period), an operation for recording the photographed image while moving the vicinity of the in-focus position is performed. It becomes easy to do.

  Further, in the above configuration, the recording control unit is configured to start recording a captured image by the recording unit in accordance with an instruction input from the instruction input unit until recording is performed while satisfying a recording capacity of the recording unit. Control may be performed to cause the recording means to record a photographed image for a certain period.

  According to this, for a certain period from when the recording control unit starts the recording operation of the photographed image by the recording unit according to the instruction input by the instruction input unit until the recording capacity of the recording unit is recorded and recorded. Since the recording means controls to record the photographed image, the instruction input operation for stopping the recording operation by the instruction input means can be made unnecessary, or at least the instruction for starting the recording operation can be input at the beginning ( Since the recording operation is automatically stopped until the recording capacity of the recording means is satisfied and the recording operation is stopped (terminated) after that, the image can be taken for a certain period in the vicinity of the in-focus position. It is possible to easily record an image with a simple operation.

  In the above configuration, the selection unit may select a photographed image with the highest degree of focus from the photographed image group based on the contrast of the photographed image.

  According to this, since the selection unit selects a captured image with the highest degree of focus from the captured image group based on the contrast of the captured image, it is most easily selected from the captured image group by a simple method (image processing). A photographed image with a high degree of focus can be selected.

  Further, in the above configuration, the image processing apparatus further includes a projecting unit that projects a predetermined slit light onto the object to be measured, and the selecting unit is configured to perform the captured image based on a feature amount indicating a focused state of a projected image by the slit light. A photographed image with the highest degree of focus may be selected from the group (claim 10).

  According to this, the predetermined slit light is projected onto the object to be measured by the projecting unit, and the most in-focus degree is obtained from the photographed image group based on the feature amount indicating the focused state of the projected image by the slit light by the selecting unit. Since a high-captured image is selected, for example, when the portable measuring instrument is a three-dimensional measuring instrument and projects predetermined slit light onto the object to be measured in order to perform the three-dimensional measurement, the existing projection Using the means (at a low cost), it is possible to easily select a photographed image with the highest degree of focus from the photographed image group based on this feature amount in the projected image.

  In the above configuration, the selection unit may select a photographed image with the highest degree of focus from the photographed image group based on the width of the slit light as the feature amount. 11).

  According to this, since the selection unit selects a photographed image with the highest degree of focus from the photographed image group based on the width of the slit light as the feature amount, the width of the slit light is referred to as Based on a simple feature amount, a captured image with the highest degree of focus can be easily selected from the captured image group.

  Further, in the above configuration, the selection unit performs shooting with the highest degree of focus from the captured image group based on the width of the slit light and the peak of the luminance distribution in the width direction as the feature amount. An image may be selected (claim 12).

  According to this, based on the size of the width of the slit light and the peak of the luminance distribution in the width direction as the feature amount, the selection unit selects the captured image with the highest degree of focus from the captured image group. Therefore, for example, a captured image (projected image) having the narrowest slit light width and the highest peak is selected, so that the captured image with the highest degree of focus can be more accurately and easily selected. Can be selected.

  In the above configuration, the selection unit may select a photographed image with the highest degree of focus from the photographed image group based on the contrast of the projected image by the slit light as the feature amount. Item 13).

  According to this, since the picked-up image with the highest degree of focus is selected from the picked-up image group based on the contrast of the projected image by the slit light as the feature amount by the selecting means, a simple method (image processing) Thus, it is possible to easily select a photographed image with the highest degree of focus from the photographed image group.

  Further, the measurement method according to the present invention is a measurement method using a portable measuring instrument capable of measuring an object to be measured while being held in a hand of a user, and images the object to be measured. An imaging process for obtaining a captured image, a recording process for recording a captured image group obtained by continuously capturing images in a predetermined period in the imaging process, and an instruction for starting a recording operation for the captured image group in the predetermined period An instruction input step for inputting, and a selection step for selecting a photographed image with the highest degree of focus from a plurality of photographed images recorded in the recording step (claim 14).

  According to the above configuration, in the measurement method using the portable measuring instrument capable of measuring the object to be measured while being held in the hand, the object to be measured is photographed by the imaging process. The captured image group obtained by continuously capturing images in a predetermined period in the imaging step is recorded by the recording step. Then, an instruction input for starting the recording operation of the photographed image group in a certain period is performed by the instruction input process, and the photographing with the highest degree of focus is performed from the plurality of photographed images recorded in the recording process by the selection process. An image is selected.

  In this way, recording of a captured image is started in response to a user's operation, and a captured image group obtained by continuously capturing images for a certain period is recorded, and the recorded captured image group is selected from the recorded captured image group. Since the photographed image with the highest degree of focus is selected, for example, the user holds the portable measuring instrument to the approximate in-focus position with his hand, and shoots for a certain period while moving the vicinity of the in-focus position. By recording the image, a group of captured images including the captured image at the in-focus position is recorded, and the focused image can be automatically acquired from the captured image group by processing by the selection unit. Therefore, even in such a portable type, the user does not need to accurately adjust the focus position with respect to the object to be measured, and so-called roughly photographing the vicinity of the focus position (recording a plurality of image frames continuously). It is possible to easily obtain a focused image.

  According to the present invention, recording of a photographed image is started in response to a user operation, and a photographed image group obtained by continuously photographing for a certain period is recorded, and the recorded photographed image group is recorded. Since the photographed image with the highest degree of focus is selected from among them, for example, the user holds the portable measuring instrument to the approximate in-focus position with his hand and moves the vicinity of the in-focus position for a certain period of time. By recording the captured image, a captured image group including the captured image at the in-focus position is recorded, and from this captured image group, automatic processing is performed by processing by a selection unit (processing for selecting a captured image with the highest degree of focus). In-focus image can be acquired. Therefore, even in such a portable type, the user does not need to accurately adjust the focus position with respect to the object to be measured, and so-called roughly photographing the vicinity of the focus position (recording a plurality of image frames continuously). It is possible to easily obtain a focused image.

(Embodiment 1)
1 is a perspective view showing a portable three-dimensional measuring apparatus 1 according to the first embodiment, FIG. 2 is a side view thereof, FIG. 3 is a perspective view showing a measurement region of the portable three-dimensional measuring apparatus 1, and FIG. These are perspective views which show the irradiation condition of the slit light S with respect to the to-be-measured object (measuring object) which has a three-dimensional shape as shown to the to-be-measured object 100, for example. The portable three-dimensional measuring apparatus 1 measures a three-dimensional shape of an object to be measured by a light cutting method, and includes a main body housing 10, slit light generating means 2 housed therein, and a light projecting optical system 3. , Imaging means 4, illumination means 5, and control unit 6. The portable three-dimensional measuring apparatus 1 illustrated here has a rod shape having a size of a general caliper, and one end side is a measuring head unit H that projects and receives the slit light S, and the other side. The end side is a grip portion G for the user to grip.

  As shown in FIG. 1, the main body housing 10 is a housing in which a head housing portion 11 corresponding to the measurement head portion H, an intermediate housing portion 12, and a grip housing portion 13 corresponding to the grip portion G are integrated. . The head housing portion 11 has a rectangular shape, and a slit light generating means 2, a light projecting optical system 3, an imaging means 4 and the like which are measurement elements necessary for three-dimensional measurement are mounted therein. A control unit 6 that controls the operation of the measurement element is mounted inside the intermediate housing unit 12. The grip housing portion 13 has a cylindrical shape so that it can be easily held, and a power supply battery (not shown) is accommodated therein. In addition, the outer peripheral surface of the grip housing part 13 is subjected to a roughening process for preventing slipping.

  The slit light generating means 2 generates a slit light S spreading in a fan shape for irradiating the object to be measured. The slit light generating means 2 includes a laser light source 21 made of, for example, a small laser light source, that is, for example, a small LD (Laser diode) that generates laser light having a visible wavelength (the light emitted from the laser light source 21 is slit light). Including an optical member (not shown) that converts the light into a slit). The optical member is made of, for example, a cylindrical lens, a cylindrical lens, or a slit plate. Further, the slit light generating means 2 is arranged on the back side of the light receiving surface of the imaging means 4, which contributes to the downsizing of the size in the X direction in FIG.

  The light projecting optical system 3 is for irradiating the measured light (measured object 100) with the slit light S (slit light projecting optical system 31). That is, the light projecting optical system 3 bypasses the slit light S emitted from the slit light generating means 2 disposed on the back side of the light receiving surface of the imaging means 4 in the vicinity of the imaging means 4, and the front direction of the imaging means 4. It provides a detour optical path that is directed to The slit light projecting optical system 31 uses the laser light emitted from the laser light source 21 as the slit light S spreading in a fan shape, and irradiates the measured light toward the object to be measured. In the present embodiment, the slit light projecting optical system 31 irradiates the object to be measured with X-direction slit light and Y-direction slit light obtained by separating one laser light in two directions, and is cross-shaped. (See FIG. 6), the X direction slit projection image and the Y direction slit projection image (cross-shaped slit light) are projected onto the surface of the object to be measured. This projected image is photographed together with the object to be measured by an imaging sensor 41 described later (a projected image by the cross-shaped slit light is reflected in the photographed image).

  Further, the light projecting optical system 3 includes a reflective surface that reflects the slit light S, and at least one of the reflective surfaces is equivalent to the arrangement position of the light receiving surface of the imaging unit 4 when viewed from the measured object side. It is arranged at a position or a position farther than that. Here, the light projecting optical system 3 includes two reflecting surfaces R1 and R2, and an example in which the reflecting surface R1 is arranged at a position farther from the arrangement position of the light receiving surface of the imaging means 4 is shown.

  The imaging means 4 (imaging unit) includes a two-dimensional imaging sensor (referred to as imaging sensor 41) such as a CCD (Charge coupled device) area sensor (the imaging means 4 has slit light S on the light receiving surface of the imaging sensor 41). Including a light receiving optical system (not shown) that forms an image of reflected light from the object to be measured including the image of the object to be measured. The light receiving surface of the imaging means 4 is disposed so as to face the object to be measured. As a result, as shown in FIG. 2, the light receiving optical axis A2 of the image pickup means 4 extends right below (Z direction). On the other hand, the light projecting optical axis A1 of the slit light S extends downward with an inclination. That is, the light projecting optical axis A1 intersects the light receiving optical axis A2 at a predetermined crossing angle. In the light cutting method, such crossing of the optical axes is essential. In the example of this figure, the intersection of the light projecting optical axis A1 and the light receiving optical axis A2 is set to be the focal plane of the light projecting optical system and the light receiving optical system. Incidentally, FIG. 3 shows a measurement area (focal plane) which is an imaging area of the imaging means 4.

  The illumination unit 5 includes an illumination light source 51 such as an LED (Light-emitting diode) or a lamp (the illumination unit 5 may include an illumination optical system for guiding illumination light from the illumination light source 51). The object to be measured is illuminated. Specifically, for example, the illumination light source 51 has LEDs arranged at four corners of the lower surface of the measuring head H (a surface facing the object to be measured), and illuminates the surface of the object to be measured with four LEDs at the four corners. It has a configuration.

  The control unit 6 includes a CPU (Central processing unit), various circuits, and the like, and controls the light emission operation of the slit light generation unit 2, the imaging operation of the imaging unit 4, and the like. Details of the control unit 6 will be described below with reference to FIG. FIG. 5 is a block diagram showing an electrical configuration of the portable three-dimensional measuring apparatus 1. The portable three-dimensional measuring apparatus 1 includes a trigger switch (SW) 7 and an external interface unit 8 in addition to the laser light source 21, the image sensor 41, the illumination light source 51, and the control unit 6 described above.

  The trigger SW 7 is a switch for starting and stopping a recording (storage) operation of a captured image obtained by the imaging sensor 41 in an image buffer frame memory 66 described later. For example, the trigger SW 7 is disposed in the grip portion G as shown in FIG. When the user presses the trigger SW 7 to turn it on, the imaging operation is recorded (captured) in the image buffer frame memory 66. While the trigger SW 7 is in the ON state, a plurality of captured images are successively recorded in the image buffer frame memory 66 in order. When the trigger SW 7 is turned off, the image recording operation is stopped (terminated). Alternatively, the recording operation is stopped when the remaining capacity of the image buffer frame memory 66 is exhausted, or the recording operation is circulated to the image buffer frame memory 66 to continue the recording operation, and the recording operation is stopped when the trigger SW 7 is turned off. Control may be performed so that the earlier one (the one in which the recording operation ends first) is selected. Note that the imaging operation by the imaging sensor 41 is performed regardless of whether the trigger SW 7 is ON or OFF. That is, by switching to the preview mode on the operation unit, for example, the image from the image sensor 41 can be displayed on the monitor unit 91 without being recorded in the image buffer frame memory 66 (preview display described later). .

  The external interface unit 8 is used to connect the portable three-dimensional measuring device 1 and an external device 9 such as a personal computer (PC) so as to allow data communication via a USB terminal or the like provided in the grip unit G or the like. Interface. The external device 9 includes a monitor unit 91 and the like, and is configured to display the captured image transmitted via the external interface unit 8. The user moves the portable three-dimensional measuring apparatus 1 (measuring head unit H) while viewing the so-called preview-displayed image (monitor image; captured image) on the monitor unit 91 (measurement object 100). Can be taken.

  The control unit 6 includes a first light emission control unit 61, a second light emission control unit 62, a timing generator (TG) 63, an AD converter 64, a digital calculation processing unit 65, an image buffer frame memory 66, an image calculation frame memory 67, A contrast calculation unit 68 and a CPU 69 are included. The first light emission control unit 61 controls the light emission operation of the laser light source 21 and is an LD drive circuit that causes the LD to oscillate. The 2nd light emission control part 62 controls the light emission operation | movement of the illumination light source 51, Comprising: It is an LED drive circuit which light-drives LED.

  The TG 63 generates a predetermined timing pulse (vertical transfer pulse, horizontal transfer pulse, charge sweep pulse, etc.) based on the reference clock given from the CPU 69 and outputs it to the imaging sensor 41 to control the imaging operation of the imaging sensor 41. Further, the analog / digital conversion operation in the AD converter 64 is controlled by outputting a predetermined timing pulse to the AD converter 64. The AD converter 64 converts the analog R, G, B image signal output from the imaging sensor 41 into a digital image signal composed of a plurality of bits (for example, 12 bits) based on the timing pulse output from the TG 63. Convert. The AD converter 64 includes a CDS (correlated double sampling) circuit, an AGC (auto gain control) circuit, a clamp circuit (clamp means), and the like at the input stage.

  The digital arithmetic processing unit 65 includes an FPGA (Field Programmable Gate Array) or the like, and performs predetermined signal processing on the image (pixel) data output from the AD converter 64 to create an image file. , A white balance control circuit, a gamma correction circuit, and the like. The contrast calculation unit 68 detects the focus of an image (photographed image), that is, detects whether or not a certain image is in focus, in other words, to determine the degree of focus of the image. The calculation process (referred to as contrast calculation) for obtaining the contrast (image plane contrast) of the image is performed. The digital arithmetic processing unit 65 also has a function of performing a calculation process for obtaining a three-dimensional shape of an object to be measured such as the object to be measured 100.

  The image buffer frame memory 66 includes a RAM (Random Access Memory) or the like, and stores image (frame image) data captured by the image sensor 41. The image data taken into the digital arithmetic processing unit 65 is written into the image buffer frame memory 66 in synchronization with the reading of the image sensor 41. The image calculation frame memory 67 is composed of a RAM or the like, and an image to be subjected to calculation processing taken out from the image buffer frame memory 66 during the contrast calculation (or calculation processing by the digital calculation processing unit 65) by the contrast calculation unit 68. (Calculation frame image) is stored.

  The CPU 69 controls the operation of each functional unit such as the first light emission control unit 61, the second light emission control unit 62, the TG 63, the digital calculation processing unit 65, and the contrast calculation unit 68 in accordance with an operation signal given from the trigger SW 7 or the like. Central processing unit. Further, the CPU 69 has a function (recording control function) for controlling a frame image recording (circular recording and cyclic overwriting described later) operation to the image buffer frame memory 66 and the image calculation frame memory 67. In addition, the CPU 69 selects the most in-focus image as a focused image from among the plurality of recorded images based on the result of the contrast calculation by the contrast calculation unit 68 for each image recorded in the image buffer frame memory 66 as described later. It also has a function (selection function) for selecting (selecting) a photographed image with a high degree of focus or a good focus state.

  Incidentally, as shown in FIG. 6, the portable three-dimensional measuring apparatus 1 is moved in the front-rear direction (vertical direction; Z direction in FIG. 1 or the perspective direction with respect to the part to be measured) (moving back and forth; moving up and down). In this case, the captured image is in focus as represented by reference numeral 201 (represented as a focused image) and in focus before and after the focused image as indicated by reference numerals 202 and 203 in accordance with the imaging position. The image is not out of focus (represented as a front pin image and a back pin image). These front and rear pin images have a greater degree of out-of-focus as they are farther from the focused image (focus position). However, “focusing” here includes focusing when the depth of field is taken into consideration. For example, even when a three-dimensional object to be measured (such as a step on the surface) such as the object to be measured 100 shown in FIG. 4 is imaged, an in-focus image having a depth is in focus. can get.

  7 and 8 are diagrams for explaining a measurement operation using the portable three-dimensional measuring apparatus 1 according to the present embodiment. FIG. 7 illustrates the portable three-dimensional measuring apparatus 1 before and after the user (operator). FIG. 8 conceptually shows a back-and-forth movement operation in this case, that is, a state in which the object to be measured is photographed while moving, that is, between the object to be measured and the portable three-dimensional measuring apparatus 1 as the object moves back and forth. It is a figure which shows a mode that the distance of changes with time. Note that the upper diagram indicated by reference numeral 310 in FIG. 7 shows a state of moving back and forth within a large range (represented by a longer front-rear movement distance) as represented by the arrow 311, and the lower diagram indicated by reference numeral 320 is indicated by the arrow 312. As shown in the figure, the state of moving back and forth within a small range (the back-and-forth movement distance is short) is shown.

  In the first stage, the user moves the portable three-dimensional measuring apparatus 1 back and forth as indicated by the reference numeral 310, and generally observes the photographed image of the object to be measured (measurement site) through the monitor (monitor unit 91). (The portable three-dimensional measuring apparatus 1 is brought to an approximate in-focus position; it does not have to coincide with the in-focus position). At this stage, the trigger SW 7 is not pressed. Then, in the next stage, as shown in the figure of reference numeral 320 above, while moving the portable three-dimensional measuring apparatus 1 slightly back and forth with the trigger SW 7 turned on, in the vicinity of the roughly focused position. Acquire a captured image.

  A line indicated by reference numeral 331 in FIG. 8 indicates the in-focus position, that is, the distance between the object to be measured and the portable three-dimensional measuring apparatus 1 when a focused image is obtained. During the period indicated by reference numeral 332 (the first stage described above), for example, as shown in the line graph indicated by reference numeral 333, the portable three-dimensional measuring apparatus 1 is moved forward and backward so as to straddle the in-focus position. Move closer to the position. However, this line graph exaggeratedly shows the state of moving back and forth so as to manually approach the in-focus position. And it is not necessary to move back and forth many times (it is not necessary to move linearly like a polygonal line). For example, by getting used to the operation, it can be brought close to the in-focus position in one operation. Good. Next, the trigger SW 7 is turned on at this approximate imaging position, that is, the timing indicated by reference numeral 334, and the portable three-dimensional measuring apparatus 1 is moved back and forth so as to sandwich the in-focus position while maintaining this ON state. When the trigger SW 7 is in the ON state, each captured image is continuously recorded in the image buffer frame memory 66.

  The period during which the image can be recorded depends on the imaging frame rate of the imaging sensor 41, the data size of the captured image, or the capacity (memory capacity) of the image buffer frame memory 66. For example, when the memory capacity is 120 Mbytes, the imaging frame rate is 60 frames / sec, and the captured image is 1 million pixels, the image recordable period is about 2 seconds. In other words, the user turns on the trigger SW 7 at the approximate in-focus position confirmed on the monitor, and moves the memory while moving back and forth slightly to include the in-focus position within the image recordable period (in this case, within 2 seconds). Write to get an image. That is, the user does not necessarily have to keep turning on the trigger SW 7 for 2 seconds and continue to record an image. Instead of waiting for 2 seconds, the user triggers when the user is confident that the photographed image at the in-focus position can be recorded. SW7 may be turned off (that is, for example, the trigger SW7 may be pressed for 1 second and image recording may be performed during that time). However, the trigger SW 7 may be kept ON for 2 seconds or more, but the image is recorded only for 2 seconds of the image recordable period, that is, the image recording operation is automatically performed when 2 seconds have passed. Stopped. Such an image recording period is a period indicated by reference numeral 335 in FIG. Note that the values of the memory capacity and the imaging frame rate are merely examples, and arbitrary values can be adopted. In particular, the imaging frame rate is sufficiently high so that the in-focus image is included in the captured image as compared to the speed at which the user moves the portable three-dimensional measuring apparatus 1 back and forth, as in the case of 60 frames / sec. It is desirable that the value be set to a small value (however, since the memory capacity is limited even if the speed is too high, an optimum value is set in consideration of the memory capacity).

  FIG. 9 is a flowchart illustrating an example of a measurement operation performed by the portable three-dimensional measurement apparatus 1 according to the first embodiment. First, when a power switch (not shown) of the portable three-dimensional measuring apparatus 1 is turned on or after the power switch is turned on, the image is taken by the imaging sensor 41 (measurement object or measurement site) by switching to a preview mode or the like. Is displayed on the monitor unit 91 (step S1). The user moves the portable three-dimensional measuring apparatus 1 to an approximate in-focus position while viewing the monitor image. Then, the trigger SW 7 is turned on at a position near the in-focus position. When the trigger SW 7 is turned on, the recording operation of the captured image in the image buffer frame memory 66 is started, and the time measurement operation (time count) is started by, for example, the CPU 69 of the control unit 6 (step S2). ). Until the trigger SW7 is turned off (YES in step S3) or until a predetermined time (for example, 2 seconds) elapses (YES in step S4), that is, the trigger SW7 is turned on (NO in step S3) and for a predetermined time. While the progress is not measured (NO in step S4), the image recording operation is continued (continuously) while the portable three-dimensional measuring apparatus 1 is moved back and forth in the vicinity of the in-focus position by the user. When the trigger SW 7 is turned off by the user or the passage of a predetermined time is measured by the CPU 69, the image recording operation is ended (step S5). Then, based on the result of the contrast calculation processing performed by the contrast calculation unit 68 for each image recorded in the image buffer frame memory 66 by the CPU 69, a focused image (the highest degree of focus) is selected from the plurality of recorded images. Alternatively, a photographed image with the best in-focus state is selected (step S6). However, in this case, the CPU 69 selects, for example, an image with the highest contrast among the recorded images as the focused image using the contrast information of the recorded images obtained by the contrast calculation.

(Embodiment 2)
In the first embodiment, it is assumed that a focused image will be included in a series of captured images (continuous image group), and the captured image is simply moved back and forth in the vicinity of the focused position. In the second embodiment, when the captured image is recorded by moving the vicinity of the in-focus position back and forth, it is determined whether or not the object to be measured is in focus. It detects (discriminates), in other words, has a focus detection function for detecting whether or not the imaging sensor 41 has taken a picture at the focus position, and automatically sets the approximate focus position (focus state) automatically (so-called The detection method is used (for AF).

  In the present embodiment, as shown in FIG. 10, the user finds an approximate focus position through the monitor while viewing the captured image of the object to be measured (measurement site), and in the state where the trigger SW 7 is turned on from the beginning, The portable three-dimensional measuring device 1a is moved in the front-rear direction so as to straddle the focal position. At this time, there is no need to move “slightly” in the vicinity of the in-focus position (as indicated by reference numeral 320) as in the first embodiment, but a large range indicated by the arrow 411 in FIG. It is only necessary to move back and forth within a rough range without worrying about whether or not it is in the vicinity of the in-focus position.

  FIG. 11 is a diagram conceptually showing the back-and-forth movement operation of the portable three-dimensional measuring apparatus 1a in the present embodiment. In the present embodiment, as shown in the figure, while performing the recording operation of the captured image with the trigger SW turned on, the focus position is crossed (crossed; sandwiched) as shown in the line graph 441. When the portable three-dimensional measuring apparatus 1a is moved back and forth within a rough range, focus detection is automatically performed, and this recording operation is stopped. As a result, a plurality of photographed images in the vicinity of the in-focus position including the photographed image when the in-focus detection is performed (an image that is assumed to be a required focused image) are recorded. This is realized with the following configuration.

  That is, in the portable three-dimensional measuring apparatus 1a, when the trigger SW is turned on as in the portable three-dimensional measuring apparatus 1, images taken by the image sensor 41 are sequentially recorded in the image buffer frame memory 66. In the type three-dimensional measuring apparatus 1a (the control unit 6a or the CPU 69), when the memory capacity of the image buffer frame memory 66 is filled by recording the captured image, the old frame in the image buffer frame memory 66 is cyclically stored. It has a function to continue the buffer in a format that overwrites (rewrites) the image and records it. This circular overwriting and recording is expressed as “circular recording” or “circular overwriting”.

  When the in-focus detection is performed, the portable three-dimensional measuring apparatus 1a (control unit 6a) has a partial predetermined memory capacity, for example, a half memory capacity, of the memory capacity of the image buffer frame memory 66 from that time. A function is provided that stops (ends) the recording operation after circular recording is performed for the number of minutes. Specifically, when this function, that is, when focus is detected, the CPU 69 executes control to stop writing after circular recording by half the memory capacity. The focus detection in this case means that the captured image is a focused image by determining the contrast of the captured image based on the contrast calculation result by the contrast calculation unit 68 (the portable three-dimensional measuring device 1a is in the in-focus position). Indicates that it is detected.

  FIG. 12 conceptually shows all photographed images recorded in the image buffer frame memory 66 (the photographed image 451 is the first photographed image recorded first in this memory capacity, that is, the photographed image. 452 is the latest recorded image). When it is detected that the photographed image 452 is a focused image, new photographed images are sequentially added and recorded from the direction of the so-called arrow 454 until the photographed image 452 reaches a half of the total memory capacity indicated by reference numeral 453. At the same time, the old photographed images are pushed out in the direction of the arrow 455 in order (the photographed image in the range indicated by reference numeral 456 is overwritten and disappears from the memory). The CPU 69 controls the contrast calculation by the contrast calculation unit 68 and the recording operation of the captured image in the image buffer frame memory 66 based on the contrast calculation result (focus detection).

  However, the memory capacity of the image buffer frame memory 66 corresponds to the image recordable period, and in this sense, the above description is a partial image of the image buffer frame memory 66 in the image recordable period. It may be considered that “memory capacity” is replaced with “recording time”, such as cyclic recording for the recordable period. When the image recordable period is 2 seconds as in the portable three-dimensional measuring apparatus 1, if the circulating recording operation is stopped 1 second after the focus detection, the 1 second before and after the focus detection is performed. Each captured image is recorded in the image buffer frame memory 66.

  As an example, when the portable three-dimensional measuring device 1a is moved from the position far from the object to be measured across the in-focus position as shown by the graph line 4111 in FIG. When the focus is detected at (timing), the captured image is overwritten and recorded in the image buffer frame memory 66 for the period indicated by the symbol F (period F; the above-mentioned 1 second) from the time when the focus is detected (FIG. 5). 13 corresponds to the period F shown in FIG. On the other hand, the captured image in the period indicated by the symbol B (period B) remains in the image buffer frame memory 66 without being overwritten (corresponding to the period B shown in FIG. 13). The cyclic recording operation is continued during the period indicated by the symbols J and B until the focus is detected. A period indicated by reference numeral 443 is an image recordable period (the above-mentioned 2 seconds; total memory capacity) of the image buffer frame memory 66.

  Even if the portable three-dimensional measuring apparatus 1 is moved again across the in-focus position with the trigger SW 7 turned on, the operation of writing the captured image into the image buffer frame memory 66 is not performed. That is, even if the user keeps the trigger SW 7 ON after the period F as an actual operation, the image recording operation is stopped when the time of the period F elapses after the focus detection (timing indicated by reference numeral 444). That is, the trigger SW 7 is substantially turned off.

  The focus detection is performed at a stage where the trigger SW 7 is turned on and the period from when the forward / backward movement is started until the focus is detected is short, that is, when the memory capacity is not satisfied and the circular recording is not yet started. Even in the case where the image recording is performed, similarly, the image recording operation is performed for a predetermined time (predetermined memory capacity) within the image recordable period from the focus detection timing, and then stopped. In this case, including the above case, the ratio of the period F to the period B in the entire image recordable period or the ratio of the number of shot images recorded before and after the focus detection is performed may not be the same. . As described above, it is desirable to record the captured images before and after the focus detection. However, this is not always necessary. The focus detection is performed immediately after the trigger SW 7 is turned on, and the image is recorded within the period F before the focus detection. There may be no captured image. In short, it is only necessary to detect the focus and record the captured image at that time in the image buffer frame memory 66 (in this case, without performing the operation of selecting the image with the highest degree of focus later) A single photographed image may be determined as a focused image).

  FIG. 14 is a flowchart illustrating an example of a measurement operation performed by the portable three-dimensional measurement apparatus 1a according to the second embodiment. First, after the power switch of the portable three-dimensional measuring apparatus 1a is turned on or the power switch is turned on, the image is taken by the image sensor 41 (the image of the object to be measured or the measurement site) by switching to the preview mode or the like. It is displayed on the monitor unit 91 (step S21). The user turns on the trigger SW 7 after obtaining the general position of the in-focus position, for example, by moving the portable three-dimensional measuring apparatus 1 a while viewing the monitor image. When the trigger SW 7 is turned on, at this time, the recording operation of the captured image in the image buffer frame memory 66 is started (step S22), and this recording operation is continued until the focus detection described later is performed. At this time, when the image is recorded in the entire memory capacity of the image buffer frame memory 66, the circular recording is started and the recording operation is continued (NO in step S23). When focus detection is performed by the CPU 69 based on the result of the contrast calculation by the contrast calculation unit 68 (at this time, for example, the CPU 69 of the control unit 6 starts a time measurement operation) (YES in step S23), the image buffer For example, half of the memory capacity of the frame memory 66 is circularly recorded (step S24), and then the circular recording operation is stopped and the recording operation of the captured image in the image buffer frame memory 66 is completed (step S25). . Then, based on the result of the contrast calculation processing performed by the contrast calculation unit 68 for each image recorded in the image buffer frame memory 66 by the CPU 69, a focused image (the highest degree of focus) is selected from the plurality of recorded images. Alternatively, a photographed image with good focus is selected (step S26). However, also in this case, the CPU 69 selects, for example, an image with the highest contrast among the recorded images as the focused image using the contrast information of the recorded images obtained by the contrast calculation.

  The present invention can take the following aspects. In the first and second embodiments, as a method for selecting an image with the highest degree of focus from the recorded image group (continuous image group) recorded in the image buffer frame memory 66, the contrast of each recorded image is selected. Although a method of performing selection based on information is adopted, the present invention is not limited to this, and for example, a feature amount indicating a focused state of a projected image by slit light (not necessarily cross-shaped slit light) by the slit light generation unit 2 Based on the above, a method of selecting an image with the highest degree of focus from the recorded image group may be employed. However, the feature amount indicates, for example, the width of the slit light. In this case, using the fact that the width of the projected slit light is the narrowest (the narrowest width) at the in-focus position, the slit light has the narrowest width (for example, the half-value width is the smallest). A recorded image with an image may be selected as the focused image. The feature amount may include not only the width of the slit light but also information on the peak of the luminance distribution in the width direction. In this case, for example, a recorded image (projected image) having the narrowest slit light width and the highest luminance distribution peak may be selected as the focused image. Further, this feature amount may be used as contrast (difference in output value between CCD pixels; difference in pixel values) information of a projected image by slit light. In this case, a recorded image (projected image) having the highest contrast of the projected image of the slit light may be selected as the focused image. Although the case of slit light is described here, the projection shape “slit” does not necessarily have to be linear light, and may be, for example, light having a circular shape or a square shape. The light of the pattern shape may be used.

  In the second embodiment, as described above (as in step S26), when selecting a focused image from the recorded image group recorded in the image buffer frame memory 66, the contrast of the recorded image. However, the present invention is not limited to this, and the captured image (recorded image) when the focus is detected by the focus detection function at the stage where the vicinity of the initial focus position is moved back and forth is captured. It may be selected as a focused image.

  In the second embodiment, focus detection is performed based on the contrast of the captured image, but the present invention is not limited to this. That is, by using the cross-shaped slit light by the slit light generating means 2, the degree of intersection of the cross-shaped slit light (intersection of the X-direction slit light and the Y-direction slit light) coincides with a predetermined position of the object to be measured ( For example, focus detection may be performed by determining the distance or the degree of focus between the intersection of the slit lights and a predetermined position.

  Further, when selecting an image with the highest degree of focus from the group of recorded images, for example, when there are a plurality of images with the same degree of focus, one of them may be selected as a representative. It is also possible to extract regions with a high degree of focus in each image, and combine the extracted regions into one image (synthesized image), or all these images have the highest degree of focus. You may select as an image.

  As described above, according to the portable measuring instrument (portable three-dimensional measuring device 1, 1a) according to the first and second embodiments of the present invention, an object to be measured (for example, a state in which the user holds it in his hand) In a portable measuring instrument capable of measuring the object to be measured 100), the object to be measured is photographed by the imaging means (imaging sensor 41) to obtain a photographed image, and the recording means (image buffer frame memory 66). Thus, a group of captured images obtained by continuously capturing images for a predetermined period by the imaging unit is recorded. Then, the instruction input means (trigger SW7) inputs an instruction for starting the recording operation of the photographed image group for a certain period, and the selection means (selection function of the CPU 69) records a plurality of photographings recorded in the recording means. A photographed image with the highest degree of focus is selected from the image.

  Moreover, according to the measurement method according to the first and second embodiments of the present invention, in the measurement method using the portable measuring instrument capable of measuring the object to be measured while being held in the hand of the user. In the imaging step, a photographed image is obtained by photographing the object to be measured, and in the recording step, a group of photographed images obtained by continuously photographing in the imaging step in a certain period is recorded. Then, an instruction input for starting the recording operation of the photographed image group in a certain period is performed by the instruction input process, and the photographing with the highest degree of focus is performed from the plurality of photographed images recorded in the recording process by the selection process. An image is selected.

  In this way, recording of a captured image is started in response to a user's operation, and a captured image group obtained by continuously capturing images for a certain period is recorded, and the recorded captured image group is selected from the recorded captured image group. Since the photographed image with the highest degree of focus is selected, for example, the user holds the portable measuring instrument to the approximate in-focus position with his hand, and shoots for a certain period while moving the vicinity of the in-focus position. By recording the image, a group of captured images including the captured image at the in-focus position is recorded, and from this captured image group, processing by a selection unit (processing for selecting a captured image with the highest degree of focus) is automatically performed. A focused image can be acquired. Therefore, even in such a portable type, the user does not need to accurately adjust the focus position with respect to the object to be measured, and so-called roughly photographing the vicinity of the focus position (recording a plurality of image frames continuously). It is possible to easily obtain a focused image. Note that this is achieved without the AF function (focusing mechanism that follows hand-held distance fluctuation; focusing optical system), so the portable measuring instrument is made compact (small) and low in cost. be able to.

  Further, since the display unit (monitor unit 91) configured to display the captured image by the imaging unit on a monitor is further provided, the user can easily view the captured image of the object to be measured while viewing the monitor display on the display unit. The focal position can be found. That is, the focused image can be surely included in the captured image group, and as a result, the focused image can be acquired more easily in the measurement by the portable measuring instrument.

  Further, whether or not the object to be measured is in focus is detected based on the photographed image by the focus detection means (contrast calculation unit 68, the focus detection function of the CPU 69), and the recording control means (CPU 69). Recording control function), when the focus detection means detects the in-focus, the recording operation by the recording means is controlled. Therefore, in the group of photographed images obtained by photographing the vicinity of the in-focus position roughly. In addition, a photographed image when focus is detected (an image that is assumed to be a focused image with the highest degree of focus, that is, a focused image, and this image is not necessarily a required focused image, that is, an image with the highest degree of focus. Can be included more easily and reliably.

  Further, the recording control means controls to record the photographic image in the recording means in a cyclic manner (circular rewriting and recording; cyclic recording). Since the captured image is cyclically recorded by the predetermined capacity of the recording capacity of the recording means from the time of detection, control is performed to stop the recording operation, so that the focus detection is performed in the recorded captured image group. In addition to the captured image when the focus is detected by the means (the image that is assumed to be the focused image as described above), the captured image (the front pin image and A rear pin image) can also be included. For this reason, it becomes possible to acquire a focused image more accurately by selecting a captured image with the highest degree of focus from these captured image groups.

  Whether the cross-shaped slit light is projected onto the object to be measured by the projecting means, and the in-focus detection means determines whether the intersection of the cross-shaped slit light matches the predetermined position of the object to be measured. For example, the portable measuring instrument is a three-dimensional measuring instrument (portable three-dimensional measuring apparatus 1, 1a), and the cross-shaped slit light is projected onto the object to be measured in order to perform the three-dimensional measurement. In this case, it is possible to easily detect the focus by using the existing projection means (slit light projecting optical system 31) (at a low cost).

  In addition, the recording control unit starts the recording operation of the photographed image by the recording unit according to the instruction input by the instruction input unit, and then stops the recording operation according to the instruction input by the instruction input unit. Control is performed to cause the recording means to record the photographed image. That is, since the photographed image is recorded only while the user presses the instruction input means, for example, the input button (trigger SW7) (a certain period), the photographed image is recorded while moving in the vicinity of the in-focus position. Can be easily performed.

  In addition, the recording means for a certain period from when the recording operation of the photographed image is started by the recording means according to the instruction input by the instruction input means until the recording capacity of the recording means is recorded. Since the control for recording the photographed image is performed, the instruction input operation for stopping the recording operation by the instruction input means can be made unnecessary, or at least when the instruction input for starting the recording operation is performed at first (start button; Since the recording operation is automatically stopped until the recording capacity of the recording unit is satisfied and the recording operation is stopped (terminated) after that, when the trigger SW7 is pressed, the image is taken for a certain period in the vicinity of the in-focus position. It is possible to easily record an image with a simple operation.

  Further, since the selection unit selects the photographed image with the highest degree of focus from the photographed image group based on the contrast of the photographed image, the simplest method (image processing) can easily select the most focused degree from the photographed image group. A high photographed image can be selected.

  Further, a predetermined slit light is projected onto the object to be measured by the projecting means, and a photographed image having the highest degree of focus from the photographed image group based on the feature amount indicating the focused state of the projected image by the slit light by the selecting means. Therefore, for example, when the portable measuring instrument is a three-dimensional measuring instrument and projects predetermined slit light onto the object to be measured in order to perform the three-dimensional measurement, the existing projection means (slit Using the light projecting optical system 31) (at a low cost), it is possible to easily select a photographed image with the highest degree of focus from the photographed image group based on this feature amount in the projected image.

  In addition, since the selection unit selects a photographed image having the highest degree of focus from the photographed image group based on the width of the slit light as the feature amount, a simple feature of the width of the slit light is selected. Based on the amount, a photographed image with the highest degree of focus can be easily selected from the photographed image group.

  Further, since the selection unit selects a photographed image with the highest degree of focus from the photographed image group based on the width of the slit light as the feature amount and the peak of the luminance distribution in the width direction, for example, A photographed image (projected image) with the narrowest slit light width and a high peak is selected, and the photographed image with the highest degree of focus is selected from the photographed image group more accurately and easily. be able to.

  Furthermore, since the selection means selects a photographed image with the highest degree of focus from the photographed image group based on the contrast of the projected image by the slit light as the feature quantity, it can be easily obtained by a simple method (image processing). A photographed image with the highest degree of focus can be selected from the photographed image group.

It is a perspective view which shows the portable three-dimensional measuring apparatus which concerns on 1st Embodiment. It is a side view of the portable three-dimensional measuring apparatus shown in FIG. It is a perspective view which shows the measurement area | region of the portable three-dimensional measuring apparatus shown in FIG. It is a perspective view which shows the irradiation condition of the slit light S with respect to the to-be-measured object (measurement object) which has a three-dimensional shape. It is a block diagram which shows the electric constitution of the portable three-dimensional measuring apparatus shown in FIG. It is a schematic diagram which shows roughly the out-of-focus image in the front and back position of a focused image and a focused image. It is a schematic diagram which shows a mode that the user is moving the portable three-dimensional measuring apparatus back and forth, and image | photographs the to-be-measured object in 1st Embodiment. It is a figure which shows notionally the movement operation | movement back and forth of the portable three-dimensional measuring apparatus in the case shown in FIG. It is a flowchart which shows an example of the measurement operation | movement by the portable three-dimensional measuring apparatus in 1st Embodiment. It is a schematic diagram which shows a mode that the user is moving the portable three-dimensional measuring apparatus back and forth, and image | photographs the to-be-measured object in 2nd Embodiment. It is a figure which shows notionally the movement operation | movement back and forth of the portable three-dimensional measuring apparatus in the case shown in FIG. FIG. 3 is a schematic diagram conceptually showing all photographed images recorded in an image buffer frame memory. In a 2nd embodiment, it is a mimetic diagram explaining recording to a memory of an in-focus picture and each photography picture in the position before and behind which sandwiches this focused picture. It is a flowchart which shows an example of the measurement operation | movement by the portable three-dimensional measuring apparatus in 2nd Embodiment.

Explanation of symbols

1, 1a Portable three-dimensional measuring device (portable measuring instrument)
2 Slit light generation means 21 Laser light source 3 Projection optical system 31 Slit projection optical system (projection means)
4 Imaging means 41 Imaging sensor (imaging means)
DESCRIPTION OF SYMBOLS 5 Illumination means 51 Illumination light source 6, 6a Control part 61 1st light emission control part 62 2nd light emission control part 65 Digital arithmetic processing part 66 Frame memory for image buffers (recording means)
67 Image calculation frame memory 68 Contrast calculation unit (focus detection means)
69 CPU (selection means, focus detection means, recording control means)
7 Trigger SW (Instruction input means)
8 External interface unit 9 External device 91 Monitor unit (display means)
10 Main body housing 100 Device under test

Claims (14)

A portable measuring instrument capable of measuring an object to be measured while being held in a hand,
Imaging means for photographing the object to be measured and obtaining a photographed image;
A recording unit for recording a group of captured images obtained by continuously capturing a predetermined period by the imaging unit;
An instruction input means for performing an instruction input for starting the recording operation of the captured image group in the predetermined period;
A portable measuring instrument comprising: selecting means for selecting a photographed image with the highest degree of focus from a plurality of photographed images recorded in the recording means.   The portable measuring instrument according to claim 1, further comprising display means configured to be able to display a monitor image taken by the imaging means. Focus detection means for detecting whether or not the object to be measured is focused based on the captured image;
The portable measuring instrument according to claim 1, further comprising: a recording control unit that performs control to stop a recording operation by the recording unit when the focusing is detected by the focusing detection unit. . The recording control means includes
The recording unit is configured to perform a control to record a captured image in a cyclic manner,
Control is performed to stop the recording operation after the captured image is cyclically recorded by a predetermined amount in the recording capacity of the recording unit from the time when the in-focus detection unit detects the in-focus state. The portable measuring instrument according to claim 3, wherein The focus detection means is
The portable measuring instrument according to claim 3 or 4, wherein whether or not the in-focus state is achieved is detected based on a contrast of the captured image. A projection means for projecting cross-shaped slit light onto the object to be measured;
The focus detection means is
5. The portable measurement according to claim 3, wherein it is detected whether or not the in-focus state is detected by determining a degree to which an intersection of the cross-shaped slit light coincides with a predetermined position of the object to be measured. vessel. The recording control means includes
In accordance with the instruction input from the instruction input means, the recording means captures an image on the recording means for a certain period after the recording operation is started by the recording means until the recording operation is stopped according to the instruction input by the instruction input means. 3. The portable measuring instrument according to claim 1, wherein control for recording an image is performed. The recording control means includes
In accordance with an instruction input from the instruction input unit, a recording image is recorded on the recording unit for a certain period after the recording operation of the recording unit is started until the recording capacity of the recording unit is recorded. The portable measuring instrument according to claim 7, wherein control for recording is performed. The selection means includes
The portable measuring instrument according to any one of claims 1 to 8, wherein a photographed image with the highest degree of focus is selected from the group of photographed images based on the contrast of the photographed image. A projection means for projecting predetermined slit light onto the object to be measured;
The selection means includes
The photographed image with the highest degree of focusing is selected from the photographed image group based on a feature amount indicating a focused state of the projected image by the slit light. Portable measuring instrument. The selection means includes
The portable measuring instrument according to claim 10, wherein a photographed image with the highest degree of focus is selected from the photographed image group based on the width of the slit light as the feature amount. The selection means includes
The photographed image having the highest degree of focus is selected from the photographed image group based on the width of the slit light and the peak of the luminance distribution in the width direction as the feature amount. 11. The portable measuring instrument according to 11. The selection means includes
The portable measuring device according to claim 10, wherein a photographed image with the highest degree of focus is selected from the photographed image group based on the contrast of the projected image by the slit light as the feature amount. A measurement method using a portable measuring instrument capable of measuring an object to be measured while being held in a hand,
An imaging step of capturing the measured object and obtaining a captured image;
A recording step of recording a group of captured images obtained by continuously capturing images in a predetermined period in the imaging step;
An instruction input step for inputting an instruction for starting the recording operation of the captured image group in the predetermined period;
And a selection step of selecting a photographed image with the highest degree of focus from a plurality of photographed images recorded in the recording step.

Images