JP2013253797A - Measuring device and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent wrong stereo measurement from being executed.SOLUTION: A measuring device includes: a two-optical-path forming optical system 120 forming two optical paths with a parallax; an optical path switcher 130 switching between the two optical paths formed by the two-optical-path forming optical system 120 by time sharing; a light shielding unit 180 partially shielding each of first light and second light such that a position for partially shielding the first light on a surface perpendicular to a direction in which the first light passing through the first optical path out of the two optical paths is different from a position for partially shielding the second light on a surface perpendicular to a direction in which the second light passing through the second optical path out of the two optical paths; an image-forming optical system 160 forming a mask figure on the basis of light partially shielded by the light shielding unit 180; an imaging unit 190 imaging a mask figure formed by the image-forming optical system 160; and a detection unit detecting the switched state of the optical paths, on the basis of a mask image obtained by imaging the mask figure by the imaging unit 190.

Description

  The present invention relates to a measuring apparatus and a program.

There is an increasing demand for quantitatively grasping measurement objects such as damage and defects inside the machine and affected areas. As a technique for quantitatively measuring measurement targets such as damage, defects, and affected parts, the same location is imaged from two directions with parallax, and the corresponding measurement on each image is performed by correlation calculation between the captured images. Stereo measurement is known in which the amount of deviation of a point is obtained, and the size and depth of an object are measured from the obtained amount of deviation by the principle of triangulation.

  Conventionally, an optical system for capturing an image with parallax has been proposed for use in stereo measurement. For example, in Patent Document 1, two optical paths are switched in a time-division manner so that only light from one of the two optical paths formed in the two-optical path forming optical system is incident on the imaging optical system. A stereo measurement apparatus including a possible time division optical path switching means is disclosed. In addition, it is disclosed that the time-division optical path switching means is composed of a rotating shielding plate.

JP 2010-128354 A

  However, when the time-division optical path switching means using the rotation type shielding plate in the stereo measurement device of Patent Document 1 cannot normally perform the shielding operation, the state cannot be detected. Thereby, for example, it may be in a state in which the shielding operation cannot be normally performed due to a failure, external vibration, or high-speed movement of the endoscope tip. When a state in which the shielding operation cannot be normally performed cannot be detected, the left eye image may be captured at the timing when the right eye image should be captured. As a result, there is a problem that stereo measurement using the right eye image and the left eye image is not performed correctly.

  Therefore, the present invention has been made in view of the above problems, and an object thereof is to provide a measurement device and a program that prevent erroneous stereo measurement from being performed.

  (1) The present invention has been made in view of the above circumstances, and one aspect of the present invention is a two-optical path forming optical system that forms two optical paths with parallax and two optical paths formed by the two-optical path forming optical system. An optical path switching unit that switches time-division, a position that partially blocks the first light in a plane perpendicular to a direction in which the first light passing through the first optical path travels among the two optical paths, and the two Each of the first light and the second light is different from the position where the second light is partially blocked on a plane perpendicular to the direction in which the second light passing through the second optical path travels. A light blocking unit that partially blocks light, an imaging optical system that forms a mask image based on light partially blocked by the light blocking unit, and an imaging unit that captures a mask image formed by the imaging optical system And an optical path based on a mask image obtained by the imaging unit capturing a mask image. A detection unit that detects a switching state, a measuring device comprising a.

  (2) In the measurement apparatus described above, one aspect of the present invention is characterized in that the detection unit detects an optical path switching state based on luminance of the mask image.

  (3) In the measurement apparatus described above, one aspect of the present invention is characterized in that the detection unit detects a switching state of an optical path based on a shape of the mask image.

  (4) In the measurement apparatus described above, one embodiment of the present invention is characterized in that an optical path switching state is detected based on the position of the mask image.

  (5) In the measurement apparatus described above, according to one aspect of the present invention, the luminance of the mask image is obtained by applying a filter that passes a signal having a predetermined spatial frequency or less to the luminance of the mask image. Based on the above, the switching state of the optical path is detected.

  (6) In the measurement device described above, according to one aspect of the present invention, the light on each of the two optical paths is blocked at a plurality of locations, and the detection unit blocks the light at the plurality of locations. The switching state of the optical path is detected based on a plurality of mask images formed in this way.

  (7) In the measurement apparatus described above, according to one aspect of the present invention, the reference light blocking unit that partially blocks each of the lights on the two optical paths, the detection unit includes the mask image, and the reference An optical path switching state is detected on the basis of a reference mask image obtained by partially blocking light by the optical light blocking unit.

  (8) In the measurement apparatus described above, one aspect of the present invention is directed to a switching instruction unit that instructs the optical path switching unit to switch an optical path, a switching state detected by the detection unit, and an instruction that the switching instruction unit performs. It is characterized by comprising a determination unit for determining whether or not to match the switching instruction signal indicating.

  (9) In the measurement apparatus described above, according to one aspect of the present invention, when the determination unit determines to match, when the stereo measurement processing unit performs stereo measurement processing and determines not to match, The stereo measurement processing by the stereo measurement processing unit is prohibited.

  (10) In the measurement apparatus described above, according to one aspect of the present invention, the optical path switching unit includes a first opening and a second opening that are disposed corresponding to the two optical paths. A diaphragm member, and a shielding member capable of alternately shielding the first opening and the second opening in a time-sharing manner, wherein the shielding member is in a state where the first opening is completely shielded Then, after shifting to a state in which the first opening is not partially shielded, the second opening is started to be shielded.

  (11) The optical path switching unit includes a single aperture member having a first opening and a second opening arranged corresponding to the two optical paths, the first opening, and the second opening. A shielding member capable of alternately shielding the opening in a time division manner, and the length of the shielding member along the axis connecting the center of the first opening and the center of the second opening is the axis. Longer than the opening length of the first opening along the axis and the opening length of the second opening along the axis, and between the outer edge of the first opening and the outer edge of the second opening The distance along the axis is less than or equal to the length added to the opening length of the first opening, and less than or equal to the length added to the opening length of the second opening. To do.

  (12) In the measurement apparatus described above, according to one aspect of the present invention, the imaging optical system includes an imaging lens for imaging, the light blocking unit includes the imaging unit, and the imaging unit. It is characterized by being located between the imaging lens located at the position closest to the lens.

  (13) In the measurement apparatus described above, according to one aspect of the present invention, the two optical path forming optical system and the one optical path forming optical system forming one optical path are configured to be interchangeable. When the forming optical system is attached, the light blocking unit is located at a position where light on the optical path formed by the one optical path forming optical system is not blocked.

  (14) In the measurement apparatus described above, one aspect of the present invention is characterized in that the light blocking unit is positioned on an optical path before the two optical path forming optical system.

  (15) In the measurement apparatus described above, one embodiment of the present invention is characterized in that the mask image is formed in an invalid pixel region on an imaging surface of the imaging unit.

  (16) According to one aspect of the present invention, there are provided two optical path forming optical systems that form two optical paths having parallax, an optical path switching unit that switches two optical paths formed by the two optical path forming optical systems in a time division manner, and the two Of the two optical paths, a position where the first light is partially blocked on a plane perpendicular to the direction in which the first light passes through the first optical path, and a second of the two optical paths that passes through the second optical path. A light blocking part for partially blocking each of the first light and the second light, so that a position at which the second light is partially blocked in a plane perpendicular to the light traveling direction; In a measuring device including an imaging optical system that forms a mask image based on light partially blocked by the blocking unit and an imaging unit that captures a mask image formed by the imaging optical system, the imaging unit is a mask Based on the mask image obtained by capturing the image, the switching state of the optical path is detected. Step a program for executing.

  According to the present invention, it is possible to prevent erroneous stereo measurement from being performed.

It is a schematic block diagram which shows the structure of the measuring device in this embodiment. It is a mimetic diagram explaining a mask image formed in an image pick-up surface, when a light interception part intercepts light. It is an example of sectional drawing when the insertion part in this embodiment is seen from the top. It is an example in case a light-blocking part exists in the position different from the light-blocking part of FIG. It is a figure for demonstrating the position which can arrange | position the light-shielding part in this embodiment. FIG. 6 is a schematic diagram showing a cross section of the insertion portion of a light beam similar to the light beam of FIG. 5. It is a figure which shows an example of the structure of the optical path switching part of this embodiment. It is a figure which shows the transition of the movement of the shielding member in this embodiment. It is the figure which showed an example of the relationship between the brightness | luminance of a mask image, and the position of a shielding member. It is a schematic block diagram which shows the structure of the image signal processing circuit in this embodiment. It is an example of the timing chart of the measuring device in this embodiment. It is a figure for demonstrating the process which performs LPF to the image signal read from a discrimination | determination area | region. It is a flowchart which shows an example of the flow of a process of the measuring device in this embodiment. It is a figure for demonstrating the process of the modification 1 of this embodiment. It is a figure for demonstrating the process of the modification 2 of this embodiment. It is a figure for demonstrating the process of the modification 3 of this embodiment.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic block diagram showing a configuration of a measuring apparatus 1 in the present embodiment. The measurement apparatus 1 includes an insertion unit 100, an operation unit 200, and a main body unit 300. The insertion unit 100 is a member for insertion as an endoscope. The operation unit 200 is a member for operating the insertion unit 100 by being held by an operator. The main body unit 300 controls the insertion unit 100 to process an image signal obtained by the insertion unit 100 capturing an image.

The insertion unit 100 includes a two-optical path forming optical system 120, an optical path switching unit 130, an imaging optical system 160, a light blocking unit 180, an imaging unit 190, and an LED 195.
The two optical path forming optical system 120 forms two optical paths with parallax. Here, the two-optical path forming optical system 120 includes a right-eye optical system 121 and a left-eye optical system 122. The two optical path forming optical system 120 is, for example, a stereo lens. The stereo lens includes a right-eye lens corresponding to the right-eye optical system 121 and a left-eye lens corresponding to the left-eye optical system 122, and forms two optical paths by forming an optical path for each lens.

The optical path switching unit 130 alternately switches the two optical paths formed by the two optical path forming optical system 120 in a time division manner. In the present embodiment, as an example, the optical path switching unit 130 will be described below as a mechanical shutter. The shutter may be a liquid crystal shutter as well as a mechanical shutter.
The light blocking unit 180 is configured to partially block the first light on a plane perpendicular to the traveling direction of the first light passing through the first optical path, and the second of the two optical paths. The first light and the second light are partially blocked so that the position where the second light is partially blocked in a plane perpendicular to the traveling direction of the second light passing through the optical path.
The image forming optical system 160 forms an image of each light obtained by partially blocking the light blocking unit 180 in a common area. For example, the imaging optical system 160 forms a mask image based on the light partially blocked by the light blocking unit 180. Here, the imaging optical system 160 has one or more imaging lenses for imaging. As an example, the light blocking unit 180 is assumed to be located between the imaging unit 190 and an imaging lens positioned closest to the imaging unit 190.

  The imaging unit 190 captures an image formed by the imaging optical system 160. For example, the imaging unit 190 captures a mask image formed by the imaging optical system. When the light passing through the left-eye optical system 122 included in the two-optical path forming optical system 120 is blocked by the shutter, the imaging unit 190 combines the light transmitted through the right-eye optical system 121 included in the two-optical path forming optical system 120. An imaged image (hereinafter referred to as a right eye image) is captured. On the other hand, when the light passing through the left-eye optical system 122 included in the two-optical path forming optical system 120 is blocked by the shutter, the imaging unit 190 receives the light passing through the left-eye optical system 122 included in the left-eye optical system 122. A formed image (hereinafter referred to as a left eye image) is captured.

  Here, the imaging unit 190 is, for example, a CCD (Charge Coupled Device) image sensor. For example, a CCD image sensor simultaneously transfers charges photoelectrically converted by a photodiode in one exposure to a CCD element corresponding to each pixel. Then, the CCD image sensor applies a transfer pulse input from a CCD signal processing circuit 310 (described later) of the main body 300 to the CCD element, and sequentially reads out charges from the CCD element. Then, the CCD image sensor outputs a CCD signal indicating the read charge to the CCD signal processing circuit 310.

Then, the imaging unit 190 outputs an image signal obtained by the conversion to the CCD signal processing circuit 310 under the control of a CCD signal processing circuit 310 (described later) of the main body unit 300.
The LED 195 is turned on or off based on a signal supplied from an LED drive circuit 380 (described later) of the main body 300.

The main body 300 includes a CCD signal processing circuit 310, a shutter drive circuit 320, an image signal processing circuit 330, a display unit 336, an image recording circuit 337, a memory 340, a CPU 350, an operation unit circuit 360, a power source A circuit 370 and an LED drive circuit 380 are provided.
Under the control of the CPU 350, the CCD signal processing circuit 310 converts the CCD signal input from the imaging unit 190 into an image signal indicating the pixel value of each pixel. Thereby, the CCD signal processing circuit 310 can generate an image signal indicating a left eye image obtained by capturing the left eye image and an image signal indicating a right eye image obtained by capturing the right eye image. Then, the CCD signal processing circuit 310 outputs the converted image signal to the shutter driving circuit 320 and the image signal processing circuit 330.

The shutter drive circuit 320 synchronizes with the timing signal input from the CCD signal processing circuit 310, and in accordance with the switching instruction instructed by the CPU 350, when the immediately preceding imaging operation is performed by the right eye optical system 121, the shutter drive circuit 320 A drive signal for driving the shutter so as to block the light passing through the optical system 121 is supplied to the shutter. As a result, the shutter blocks light that has passed through the right-eye optical system 121 in accordance with the drive signal.
On the other hand, the shutter drive circuit 320 synchronizes with the timing signal input from the CCD signal processing circuit 310 and follows the switching instruction instructed by the CPU 350 when the previous imaging operation is performed by the left-eye optical system 122. Then, a drive signal for driving the shutter so as to block the light passing through the left-eye optical system 122 is supplied to the shutter. As a result, the shutter blocks light that has passed through the left-eye optical system 122 in accordance with the drive signal.

  The image signal processing circuit 330 causes the display unit 336 to display an image indicated by the image signal input from the CCD signal processing circuit 310 under the control of the CPU 350. The image signal processing circuit 330 outputs an image signal to the image storage circuit 337. Thereby, the image storage circuit holds the image signal input from the image signal processing circuit 330.

The memory 340 stores various programs that are read and executed by the CPU 350. The memory 340 is, for example, a RAM (Random Access Memory).
The operation unit circuit 360 receives an input (for example, an image processing parameter) from an operator who operates the measuring apparatus 1, and outputs input information indicating the received input to the CPU 350.
The power supply circuit 370 supplies power to each part of the main body part 300. The LED drive circuit 380 generates a signal for driving the LED 195 and supplies the generated signal to the LED 195.

The CPU 350 reads various programs from the memory 340 and executes the read programs. Thus, the CPU 350 controls the shutter drive circuit 320, the CCD signal processing circuit 310, the image signal processing circuit 330, and the operation unit circuit 360.
Further, the CPU 350 causes the image signal processing circuit 330 to change the image processing performed by the image signal processing circuit 330 based on input information (for example, image processing parameters) input from the operation unit circuit 360. Thereby, for example, the image processing executed by the image signal processing circuit 330 according to the parameters of the image processing is changed, so that the image displayed on the display unit 336 changes.

FIG. 2 is a schematic diagram illustrating a mask image formed on the imaging surface when the light blocking unit 180 blocks light. Here, the mask image is an image formed when the light blocking unit 180 partially blocks light. In the drawing, a schematic view of the insertion unit 100 as viewed from above and an imaging surface of the imaging unit 190 are shown. In the schematic diagram of the figure, it is assumed that the light passing through the right-eye optical system 121 is completely blocked by the optical path switching unit 130 and the optical path switching unit 130 passes the light passing through the left-eye optical system 122 as it is. ing.
It is shown that the light that has passed through the left-eye optical system 122 is partially blocked by the light blocking unit 180, so that a mask image appears in a part of the left-eye mask formation region included in the imaging surface of the imaging unit 190. .

  That is, when light that has passed through the left-eye optical system 122 is incident on the imaging unit 190, a part of the left-eye mask formation region included in the imaging surface becomes dark. On the other hand, when the light having passed through the right-eye optical system 121 is incident, a part of the right-eye mask formation region included in the imaging surface becomes dark. As described above, the mask image is an image of a region that is darker than the other regions included in the mask formation region in the mask formation region when the light blocking unit 180 partially blocks light.

In the present embodiment, it is assumed that the position of the light blocking unit 180 is adjusted so that the mask formation region is located in an invalid pixel region that is used for imaging but not used for observation display. Thereby, since the measuring apparatus 1 does not form an extra mask image for the effective pixel area, the quality of the image can be improved.
Note that the mask formation region may be located in an effective pixel region used for normal endoscope observation display.

  FIG. 3 is an example of a cross-sectional view of the insertion portion 100 according to this embodiment as viewed from above. In the figure, an insertion unit 100 includes a first cover glass 110, a two-optical path forming optical system 120, an optical path switching unit 130, a correction optical system 140, a second cover glass 150, and an imaging optical system 160. And a third cover glass 170, a light blocking unit 180, and an imaging unit 190. In the figure, the two-optical path forming optical system 120 includes a right-eye optical system 121 and a left-eye optical system 122. In the drawing, a plurality of light trajectories in which light incident from the outside passes through the left-eye optical system 122 and is collected on the imaging unit 190 are shown.

The first cover glass 110 protects the two optical path forming optical system 120. The first cover glass 110 allows light incident from the outside to pass through the two optical path forming optical system 120.
The two optical path forming optical system 120 forms two optical paths with parallax. Specifically, the right-eye optical system 121 collects light incident through the first cover glass 110 on the optical path switching unit 130. This condensed light is referred to as first light. In addition, the left-eye optical system 122 focuses incident light that has passed through the first cover glass 110 on the optical path switching unit 130. This condensed light is referred to as second light. The two-optical path forming optical system 120 adjusts the viewing angle.

  The optical path switching unit 130 switches two optical paths alternately in a time division manner. Specifically, for example, the optical path switching unit 130 alternately blocks the first light and the second light collected by the two optical path forming optical system 120 at a predetermined cycle. Then, the optical path switching unit 130 guides the first light or the second light to the correction optical system 140.

  The correction optical system 140 corrects the aberration of the first light or the second light guided by the optical path switching unit 130. Then, the correction optical system 140 applies the first light after correction (hereinafter referred to as first correction light) or the second light after correction (hereinafter referred to as second correction light) to the second cover. Guide to glass 150.

The second cover glass 150 protects the optical member inside the insertion portion 100. The second cover glass 150 passes the first correction light or the second correction light guided by the correction optical system 140 to the imaging optical system 160.
The imaging optical system 160 images the first correction light or the second correction light passed through the second cover glass 150 on the imaging unit 190. Specifically, the imaging optical system 160 condenses the first correction light and guides the condensed first light to the imaging unit 190. In addition, the imaging optical system 160 condenses the second correction light and guides the condensed second light to the imaging unit 190.

The third cover glass 170 protects the imaging surface and prevents adhesion of dust.
For example, the light blocking unit 180 is located between the imaging optical system 160 and the imaging unit 190. The light blocking unit 180 blocks a part of the first light (hereinafter referred to as the first light for focusing process) in the focusing process by the imaging optical system 160. In addition, the light blocking unit 180 blocks a part of the second light (hereinafter referred to as the second light for focusing process) in the focusing process by the imaging optical system 160. Here, a position where the light blocking unit 180 partially blocks the first condensing process light in a plane perpendicular to the direction in which the first condensing process light travels, and the direction in which the second condensing process light travels The position where the light blocking unit 180 partially blocks the second light for condensing light on a vertical plane is different.

  The imaging unit 190 converts the light after the light blocking unit 180 partially blocks the first condensing process light into an electrical signal. In addition, the imaging unit 190 converts the light after the light blocking unit 180 partially blocks the second condensing process light into an electrical signal. Here, an image obtained when the imaging unit 190 images an image formed by the light through the right-eye optical system 121 and formed on the imaging unit 190 is referred to as a right-eye image. On the other hand, an image obtained when the imaging unit 190 images an image formed by the light through the left-eye optical system 122 and formed on the imaging unit 190 is referred to as a left-eye image. The light blocking unit 180 acts to form a dark part in a part of the left eye image and the right eye image.

  In the present embodiment, as shown in FIG. 3, the light blocking unit 180 is positioned between the imaging optical system 160 and the imaging unit 190 as an example, but the present invention is not limited to this. For example, as shown in FIG. 4 to be described later, the light blocking unit 180 may be positioned on the optical path before the two optical path forming optical system 120. That is, the light blocking unit 180 may be located at a position where a part of the light incident on the two-light path forming optical system 120 is blocked.

  FIG. 4 is an example when the light blocking unit 180b is located at a different position from the light blocking unit 180 of FIG. In the same figure, it is shown that the light blocking part 180b is located between the first cover glass 110 and the two optical path forming optical system 120. The light blocking unit 180b in the figure partially blocks light (first incident light) incident on the right-eye optical system 121 from the outside through the first cover glass 110. In the figure, as an example, the light blocking unit 180b partially blocks the first light immediately before the first light is incident on the two-light path forming optical system 120.

  Further, as an example, the light blocking unit 180b partially blocks light (second incident light) incident from the outside through the first cover glass 110 and entering the left-eye optical system 122. Here, the position where the light blocking portion 180b partially blocks the first incident light on the surface perpendicular to the direction in which the first incident light travels, and the second incident light on the surface perpendicular to the direction in which the second incident light travels. The light blocking portion 180b is configured so that the position where the light blocking portion 180b partially blocks is different.

  The positions of the light blocking portions 180 and 180b need to be higher than the brightness contrast of the mask image and the positions and shapes of the left and right eye images change. Therefore, in this embodiment, as an example, the light blocking unit 180 is located at a position satisfying the above condition at an intermediate position between the imaging optical system and the imaging element as shown in FIG. In this case, the contrast of the mask image and the mask projection at the time of switching between the left and right eyes change depending on the position in the longitudinal direction of the front surface of the image sensor, so that the design is made in consideration thereof. The light blocking unit 180 (FIG. 3) of the present embodiment has an advantage that it can be used with a larger size than the light blocking unit 180b of FIG.

  In addition, in the case of a product specification in which the front optical unit can be removed, it is assumed that the binocular lens is replaced with a monocular lens type. In the case of a monocular lens, an optical path is formed in the central portion of the imaging optical system 160. Is done. Therefore, the light blocking unit 180 may be projected only in the case of a binocular lens by appropriately setting the position of the light blocking unit 180. That is, the two optical path forming optical system 120 and the one optical path forming optical system that forms one optical path are configured to be interchangeable, and when the one optical path forming optical system is attached, the light blocking unit 180 is You may position in the position which does not interrupt | block the light on the optical path which one optical path formation optical system forms.

  On the other hand, in the case of the configuration of FIG. 4, the size of the member of the light blocking unit 180 is reduced, but the mask arrangement design considering adapter replacement is not necessary. It is desirable to set the mask position as appropriate in accordance with the specifications and manufacturing capabilities of products that employ this mask technology.

  FIG. 5 is a diagram for explaining positions where the light blocking unit 180 according to this embodiment can be arranged. In the same figure, the diaphragm 41 is shown at a position A that is between the imaging lens 161 provided in the imaging optical system 160 and the imaging unit 190 and is in contact with the imaging lens 161. In addition, the diaphragm 42 is shown when it is located at a position B that is between the imaging lens 161 and the imaging unit 190 and is in contact with the imaging unit 190. Further, the diaphragm 43 is shown when it is at a position B ′ that is a position closer to the subject 44 than the imaging lens 161.

  As shown by the ray locus LW1 in the figure, it is shown that the light emitted from the position P45 included in the subject 44 is condensed on P46 of the imaging unit 190 via the imaging lens 161. Also, as shown by the ray locus LW2 in the figure, it is shown that the light emitted from the position P47 included in the subject 44 is condensed on P48 of the imaging unit 190 via the imaging lens 161. Yes.

As general knowledge, there is a stop at a position close to the imaging lens 161 for forming an image on the imaging surface of the imaging unit 190, that is, a position where the spread width of the light beam is wide (for example, position A in FIG. 5). The diaphragm acts as a brightness diaphragm (also referred to as an aperture diaphragm) and acts to change the brightness and resolution of the image. In this case, the aperture image is not projected onto the imaging surface.
On the other hand, if there is a stop at a position close to the imaging surface or the subject, that is, a position where the light beam is narrow (for example, position B, position B ′ in FIG. 5), the stop acts as a field stop, and the brightness of the image. Does not change, but acts to change the field of view (light vignetting). In this case, the image of the aperture is projected on the imaging surface. When it is disposed between the two positions, an intermediate squeezing action occurs.

  The optical system in the present embodiment will be applied to the above general knowledge. FIG. 6 is a schematic diagram showing a cross section of the insertion portion 100 with the same light beam as that of FIG. In the figure, the ray locus LW3 is indicated by a broken line. It is desirable to install the light blocking unit 180 in a portion where the width of the light beam is narrow, such as the region of the position 51 or the region of the position 52. By installing in such a manner, a mask image for discriminating the left eye image and the right eye image can be projected on the imaging surface of the imaging unit 190 with high contrast.

  However, in the case of the position 52, it is necessary to be careful because the mask pattern at the time of switching between the left and right optical paths is not switched too close to the imaging position of the mask. Therefore, a mask is installed at a position slightly away from the imaging surface (for example, position 53). Here, the position slightly away from the imaging surface is a position away from the imaging surface by a predetermined distance and is a position closer to the imaging unit 190 than the imaging optical system 160.

That is, the conditions required for the position of the light blocking unit 180 are as follows. When the optical paths of the left and right eyes are switched, the projection state of the light blocking unit 180 is switched, and the brightness of the mask image at that time is a sufficiently dark position. Sufficiently dark means that, for example, it is darker than the dark brightness assumed by a change in the external environment.
Specifically, the light blocking unit 180 is positioned closer to the subject than the two-optical path forming optical system 120, for example, at a position 51. Alternatively, for example, the light blocking unit 180 is positioned at a predetermined distance from the imaging surface, such as the position 53, and is positioned closer to the imaging unit 190 than the imaging optical system 160.

  In the present embodiment, the light blocking unit 180 is a position that is a predetermined distance away from the imaging surface, such as the position 53, and is closer to the imaging unit 190 than the imaging optical system 160. However, the present invention is not limited to this, and the light blocking unit 180 may be positioned at least between the imaging optical system 160 and the imaging unit 190.

  FIG. 7 is a diagram illustrating an example of the structure of the optical path switching unit 130 of the present embodiment. FIG. 6 is a diagram illustrating an example of the optical path switching unit 130 when viewed from the imaging unit 190. In the example of the figure, the optical path switching unit 130 includes a diaphragm member 131 and a shielding member 134. The aperture member 131 has a right-eye opening 132 and a left-eye opening 133. The right eye opening 132 allows light incident from the right eye optical system 121 to pass therethrough. On the other hand, the left eye opening 133 allows the light incident from the left eye optical system 122 to pass therethrough.

  The shielding member 134 shields one of the right-eye opening 132 and the left-eye opening 133 based on the drive signal supplied from the shutter drive circuit 320. Specifically, for example, the shielding member 134 moves its position based on the drive signal supplied from the shutter drive circuit 320. For example, in the case of a drive signal that drives the shutter so as to block light that has passed through the right-eye optical system 121, the shielding member 134 moves to a position that shields the right-eye opening 132. On the other hand, for example, in the case of a drive signal that drives the shutter so as to block the light that has passed through the left-eye optical system 122, the shielding member 134 moves to a position that shields the left-eye opening 133.

  Thus, when the shielding member 134 shields the right-eye opening 132, the shielding member 134 blocks the light incident from the right-eye optical system 121, so that the optical path switching unit 130 enters from the left-eye optical system 122. Only let the light through. In that case, the imaging device 190 captures an image formed by the light passing through the left-eye optical system 122, so that the measuring device 1 can obtain a left-eye image. On the other hand, when the shielding member 134 shields the left-eye opening 133, the shielding member 134 blocks the light incident from the left-eye optical system 122, so that the optical path switching unit 130 enters from the right-eye optical system 121. Pass only light. In that case, the imaging device 190 captures an image formed by the light passing through the right-eye optical system 121, so that the measuring device 1 can obtain a right-eye image.

Here, it is assumed that the optical path switching unit 130 is disposed at a position corresponding to the aperture stop (for example, position A in FIG. 5). Assuming that, the optical path switching unit 130 is positioned between the right-eye optical system 121 and the left-eye optical system 122, and a part of the light passing through the right-eye optical system 121 or the left-eye optical system 122 is blocked. When imaging is performed, the symptom that the pupil position of the image shifts appears. In this case, there is a problem that a stereo measurement value using the video has an error. Also, light that is unnecessary for each other enters.
Further, for example, when imaging is performed in a state where the right-eye optical system 121 is completely shielded and a part of the light passing through the left-eye optical system 122 is shielded, there is a symptom that the pupil position of the image is shifted. appear. In this case, there is a problem that a stereo measurement value using the video has an error.

  Therefore, in this embodiment, as shown in FIG. 8, after the shielding member 134 starts to open from the state where one of the openings (hereinafter also referred to as the first opening) is completely shielded, the other opening is opened. The dimensions of the shielding member 134, the right-eye opening 132, and the left-eye opening 133 are determined so that the part (hereinafter also referred to as a second opening) starts to be shielded from the state where it is completely opened. In other words, the shielding member 134 is configured to start shielding the second opening after transitioning from a state where the first opening is completely shielded to a state where the first opening is not partially shielded. The

  For example, as illustrated in FIG. 7, the shielding member 134 has a disk shape, the right eye opening 132 has a circular shape, and the left eye opening 133 has a circular shape. The condition of the dimension 134 will be described. In FIG. 7, Lm is the length of the shielding member 134 along the axis A <b> 1 that connects the center of the right-eye opening 132 and the center of the left-eye opening 133. L1 is the opening length of the right-eye opening 132 along the axis A1. L2 is the opening length of the left-eye opening 133 along the axis A1. D is a distance along the axis A <b> 1 between the outer edge of the right-eye opening 132 and the outer edge of the left-eye opening 133.

  Here, it is assumed that the center of the shielding member 134 moves along an axis A1 passing through the center of the right-eye opening 132 and the center of the left-eye opening 133. In this case, the length Lm of the shielding member 134 along the axis A1 passing through the center C1 of the right-eye opening 132 and the center C2 of the left-eye opening 133 is the opening length of the right-eye opening 132 along the axis A1. L1 and an axis A1 longer than the opening length L2 of the second opening along the axis A1 (Lm> L1, Lm> L2) and between the outer edge of the right eye opening 132 and the outer edge of the left eye opening 133 Is shorter than the length obtained by adding the distance D along the opening length L1 of the right-eye opening 132 (Lm ≦ L1 + D) and shorter than the length obtained by adding the distance D to the opening length L2 of the left-eye opening 133 ( Lm ≦ L2 + D).

  Generalizing the above, the center of the shielding member 134 moves along an axis passing through the center of the first opening and the center of the second opening, and the length of the shielding member 134 along the axis is An opening length of the first opening along the axis and an opening length of the second opening along the axis, and between the outer edge of the first opening and the outer edge of the second opening. The distance along the axis is equal to or less than the length obtained by adding the opening length of the first opening, and the distance is equal to or less than the length obtained by adding the distance to the opening length of the second opening.

  The shape of the shielding member may be an elliptical disk, and the shape of the first opening and the shape of the second opening may be oval. When the shape of the shielding member 134 is an ellipse, the shape of the shielding member 134 is an ellipse, the shape of the first opening is an ellipse, and the shape of the second opening is an ellipse, the configuration is as described above. That's fine. In this case, however, it is assumed that the center of the shielding member 134 moves along an axis passing through the center of the first opening and the center of the second opening.

  FIG. 8 is a diagram showing a transition of movement of the shielding member 134 in the present embodiment. In the figure, as an example, it is assumed that the position of the shielding member 134 changes in the order of FIGS. 8A, 8B, and 8C. FIG. 8A is a schematic diagram when the shielding member 134 is located at a position where the right-eye opening 132 is completely shielded (hereinafter referred to as a right-eye shielding position). FIG. 8B is a schematic view when the shielding member 134 is located at a position where the right-eye opening 132 is partially opened (right-eye partially opened position). FIG. 8B shows that the right-eye opening 132 is partially opened, but the left-eye opening 133 is not shielded by the shielding member 134. FIG. 8C is a schematic diagram when the shielding member 134 is positioned at a position (intermediate position) where both the right-eye opening 132 and the left-eye opening 133 are partially shielded.

  When the position of the shielding member 134 changes in the order of FIGS. 8A, 8 </ b> B, and 8 </ b> C, the shielding member 134 is opened from the state in which the right-eye opening 132 is completely shielded. After starting to start, the left eye opening 133 starts to be shielded from the fully opened state. The shielding member 134 moves along an axis through which the center of the shielding member 134 passes through the center of the right eye opening 132 and the center of the left eye opening 133.

  As the opening / closing state of each opening changes as shown in FIG. 8, the luminance of the mask image changes as shown in the graph of FIG. 9. FIG. 9 is a diagram illustrating an example of the relationship between the brightness of the mask image and the position of the shielding member 134. Here, the brightness of the mask image is a brightness value at one point in the mask image. In the same figure, when the shielding member 134 is in the right eye shielding position, the upper limit of luminance 71 of the mask image in the right eye mask forming area, the average luminance 72 of the mask image in the right eye mask forming area, and the mask image of the right eye mask forming area. It is indicated that the luminance lower limit 73 is higher than the threshold value 79. On the other hand, when the shielding member 134 is also in the right eye shielding position, the luminance upper limit 74 of the mask image in the left eye mask formation region, the luminance average 75 of the mask image in the left eye mask formation region, and the luminance of the mask image in the left eye mask formation region The lower limit 76 is the normal mask luminance 78, which indicates that the luminance is lower than the threshold 79. Here, the regular mask brightness 78 is the brightness of the mask image when the shielding member 134 completely shields either the right-eye opening 132 or the left-eye opening 133.

  Also, in the same figure, when the shielding member 134 is in a position where the left eye opening 133 is completely shielded (hereinafter referred to as the left eye shielding position), it is opposite to the right eye shielding position when the shielding member 134 is in the right eye shielding position. The upper limit luminance 71 of the mask image in the mask formation region, the average luminance 72 of the mask image in the right eye mask formation region, and the lower luminance limit 73 of the mask image in the right eye mask formation region become the normal mask luminance 78, which is lower than the threshold 79. It is shown that there is. On the other hand, when the shielding member 134 is also in the left eye shielding position, the luminance upper limit 74 of the mask image in the left eye mask formation region, the luminance average 75 of the mask image in the left eye mask formation region, and the luminance of the mask image in the left eye mask formation region It is shown that the lower limit 76 is higher than the threshold 79.

  In the same figure, when the shielding member 134 is at an intermediate position of each opening (for example, the position of the shielding member 134 in FIG. 8C), the lower limit luminance 73 of the mask image in the left eye mask formation region and the right eye mask formation Both of the luminance lower limits 76 of the mask image of the region are shown to have a luminance exceeding the threshold value 79. That is, when the shielding member 134 is at an intermediate position between the openings, the luminance value of the mask image is higher than the luminance of the regular mask image. Utilizing this, the measuring device 1 of the present embodiment sets the threshold appropriately, so that the shielding member 134 is in the intermediate position, or a position that completely shields one of the openings, that is, It is detected whether or not the other opening is completely open.

  FIG. 10 is a schematic block diagram showing the configuration of the image signal processing circuit 330 in the present embodiment. The image signal processing circuit 330 includes an image memory 331, a detection unit 332, an image adjustment processing unit 334, and a GUI (Graphical User Interface) composition processing unit 335.

The image memory 331 holds the image signal input from the CCD signal processing circuit 310 as image information.
The detection unit 332 detects the switching state of the optical path based on the mask image obtained by the imaging unit 190 capturing a mask image. Here, the detection unit 332 includes a shutter position detection processing unit 333.

  The shutter position detection processing unit 333 reads image information from the image memory 331, and detects the switching state of the optical path from the dark part pattern detected by the imaging unit 190. Specifically, for example, the shutter position detection processing unit 333 detects the position of the shielding member 134 based on a luminance value represented by an image signal corresponding to a predetermined set of detection ranges on the imaging surface. Details of the processing of the shutter position detection processing unit 333 will be described later. Hereinafter, detecting the position of the shielding member 134 as the shutter position and detecting the position of the shielding member 134 is also referred to as shutter position detection. The shutter position detection processing unit 333 outputs shutter position information indicating the detected position of the shielding member 134 to the CPU 350.

  The image adjustment processing unit 334 reads image information from the image memory, and performs noise reduction processing, edge enhancement processing, and hue adjustment processing on the read image information as an example. Then, the image adjustment processing unit 334 outputs the adjusted image information obtained by performing the above-described processing to the GUI composition processing unit 335.

  The GUI composition processing unit 335 generates a menu for the user to control the measuring apparatus 1. Then, the GUI composition processing unit 335 causes the display unit 336 to display the generated menu. In addition, the GUI composition processing unit 335 causes the display unit 336 to display the image indicated by the adjusted image information input from the image adjustment processing unit 334.

  FIG. 10 also shows the logical configuration of the CPU 350. The CPU 350 functions as a switching instruction unit 351, a determination unit 352, and a stereo measurement processing unit 353. The switching instruction unit 351 generates a switching instruction signal that instructs switching of the shutter, and outputs the generated switching instruction signal to the shutter driving circuit 320. Here, the switching instruction signal is, for example, an instruction to shield the left eye opening 133 when the right eye opening 132 is shielded, and when the left eye opening 133 is shielded, the right eye opening. This is an instruction to shield 132.

  Subsequently, the shutter driving circuit 320 supplies a shutter driving instruction signal to the optical path switching unit 130 based on the switching instruction signal input from the switching instruction unit 351. Thereby, the optical path switching unit 130 switches the optical path according to the shutter drive instruction signal.

The determination unit 352 determines whether or not the position of the shielding member 134 indicated by the shutter position information input from the shutter position detection processing unit 333 matches the position indicated by the switching instruction signal. The determination unit 352 causes the stereo measurement processing unit 353 to execute stereo measurement processing when it is determined that they are matched, and prohibits stereo measurement processing by the stereo measurement processing unit 353 when it is determined that they are not matched.
The stereo measurement processing unit 353 executes the stereo measurement process only when it is determined that the determination unit 352 matches. Then, the stereo measurement processing unit 353 causes the display unit 336 to display the processing result of the stereo measurement processing.

  FIG. 11 is an example of a timing chart of the measuring apparatus 1 in the present embodiment. In the figure, at time t1, the switching instruction unit 351 outputs a switching instruction signal indicating a shutter switching instruction to the shutter driving circuit 320. The switching instruction signal at this time is, for example, an instruction for shielding the right eye opening 132. The CCD signal processing circuit 310 sequentially performs exposure and readout on the CCD as the imaging unit 190. The shutter position detection processing unit 333 detects the position of the shielding member 134 at time t2, which is the timing for completing the CCD reading. At time t3, one shutter position detection process by the shutter position detection processing unit 333 is completed.

  In addition, at time t <b> 2 that is the timing of completion of reading of the CCD, the switching instruction unit 351 outputs a switching instruction signal indicating a shutter switching instruction to the shutter driving circuit 320. The switching instruction signal at this time is, for example, an instruction for shielding the left eye opening 133. The CCD signal processing circuit 310 sequentially performs exposure and readout on the CCD as the imaging unit 190. The shutter position detection processing unit 333 detects the position of the shielding member 134 at time t4, which is the timing for completing the CCD reading. At time t5, one shutter position detection process by the shutter position detection processing unit 333 is completed.

  Next, details of the processing of the shutter position detection processing unit 333 will be described. For example, the shutter position detection processing unit 333 detects the luminance of the image signal in both the left eye mask formation region and the image formation unit 190. Then, the shutter position detection processing unit 333 determines the shutter position by comparing each detected luminance with a preset threshold value. For example, the shutter position detection processing unit 333 determines that the shutter position is at the right eye occlusion position when the luminance value of the image signal in the detection area in the left eye mask formation area is equal to or lower than the threshold value. On the other hand, the shutter position detection processing unit 333 determines that the shutter position is at the left-eye shielding position when the luminance of the image signal in the detection area in the right-eye mask formation area is equal to or lower than the threshold value. As described above, as an example, the shutter position detection processing unit 333 in the present embodiment detects the switching state of the optical path based on the luminance of the mask image area.

  Here, the threshold value needs to be set to a level that prevents erroneous detection due to the noise of the image signal read from the mask image. However, if the preset threshold value is large, there is a high possibility that the brightness level of the dark image assumed at the time of normal observation will be equal to or less than the threshold value, and the measurement apparatus 1 will easily detect the dark image as a mask image. .

In order to avoid the erroneous detection, the shutter position detection processing unit 333 performs a low-pass filter (hereinafter referred to as “LPF”) process on the image signal before comparing the image signal read from the discrimination region with a threshold value. Here, the discriminating region is a general term for a right-eye mask forming region and a left-eye mask forming region. That is, the shutter position detection processing unit 333 of the detection unit 332 applies a filter that passes a signal having a predetermined spatial frequency or less to the luminance of the mask image, and is based on the luminance of the mask image after applying the filter. Then, the switching state of the optical path is detected. Specifically, for example, the shutter position detection processing unit 333 detects the optical path switching state by comparing the image signal after LPF with a threshold value. Thereby, the probability of the erroneous detection described above can be lowered by lowering the preset threshold value.
It should be noted that the image signal read out from the discrimination region may be averaged without being limited to the LPF.

  FIG. 12 is a diagram for explaining processing for applying LPF to an image signal read from the discrimination area. This figure shows an imaging surface D110 when a mask image is formed in the left-eye mask formation region. In addition, the detection range in which the mask image is detected on the imaging surface D110 is shown in FIG. In the example in the figure, since a mask image is formed in the left-eye mask formation region, a mask image R111 is shown in the detection range of the left-eye mask formation region. On the other hand, in this example, since a mask image is not formed in the right eye mask formation region, the normal observation image R112 is shown in the detection range of the right eye mask formation region.

  A graph G111 in the figure is a graph showing an example of the relationship between the position of the mask formation region for the left eye including the mask image R111 and the luminance value represented by the image signal corresponding to the mask image R111. The vertical axis represents the luminance value, and the horizontal axis represents the position in the major axis direction of the left-eye mask formation region. In the graph G111, as an example, the luminance distribution S110 of the image signal on which the noise component S111 is superimposed is shown. A broken line in the graph G111 indicates the luminance distribution of the image signal before the noise component S111 is superimposed. It is shown that the luminance value included in the luminance distribution S110 of the image signal on which the noise component S111 is superimposed is larger than the threshold in a part of the detection range.

A graph G113 in the figure is a graph showing an example of a relationship between the position of the right-eye mask formation region including the normal observation image R112 and the luminance value represented by the image signal corresponding to the normal observation image R112. The vertical axis represents the luminance value, and the horizontal axis represents the position of the right eye mask formation region in the major axis direction. In the graph G113, as an example, it is shown that the luminance values included in the image signal S113 are all higher than the threshold value in the detection range.
As described above, when the same threshold value is set in the graph G111 and the graph G113, the luminance values in the detection range both exceed the threshold value, and the shutter position detection processing unit 333 may not be able to detect the shutter position. .

  The graph G112 in the figure shows the position of the mask formation region for the left eye including the mask image R111 and the luminance distribution S112 of the image signal after LPF is applied to the luminance distribution S110 of the image signal corresponding to the mask image R111. It is the graph which showed an example of the relationship of the luminance value to represent. The vertical axis represents the luminance value, and the horizontal axis represents the position in the major axis direction of the left-eye mask formation region. It is shown that the luminance values included in the luminance distribution S112 of the image signal after being subjected to the LPF are all smaller than the threshold value in the detection range.

  The graph G114 in the figure shows the position of the mask formation region for the left eye including the normal observation image R112 and the luminance distribution of the image signal after the LPF is applied to the luminance distribution S113 of the image signal corresponding to the normal observation image R112. It is the graph which showed an example of the relationship of the luminance value which S114 represents. The vertical axis represents the luminance value, and the horizontal axis represents the position of the right eye mask formation region in the major axis direction. It is shown that the luminance values included in the luminance distribution S114 of the image signal after being subjected to the LPF are all smaller than the threshold value in the detection range.

When the graph G112 and the graph G114 are compared, the luminance value represented by the image signal corresponding to the mask image R111 in the detection range is smaller than the threshold value. On the other hand, the luminance value represented by the image signal corresponding to the normal observation image R112 in the detection range is larger than the threshold value.
In this manner, the shutter position detection processing unit 333 performs LPF to remove the noise component superimposed on the image signal, thereby generating an image signal corresponding to the mask image and an image signal corresponding to the normal observation image. Can be determined. As a result, the shutter position detection processing unit 333 can improve the detection accuracy of the shutter position.

  FIG. 13 is a flowchart illustrating an example of a processing flow of the measurement apparatus 1 in the present embodiment. The switching instruction unit 351 generates a switching instruction signal indicating a shutter switching instruction, and outputs the generated switching instruction signal to the shutter drive circuit 320 (step S101). The CPU 350 controls the CCD signal processing circuit 310 to cause the imaging unit 190 to capture an image (step S102). Next, the shutter position detection processing unit 333 detects the shutter position (step S103).

  The determination unit 352 determines whether or not the detected shutter position is the same as the switching instruction indicated by the switching instruction signal (step S104). If the detected shutter position and the switching instruction indicated by the switching instruction signal are the same (YES in step S104), the stereo measurement processing unit 353 executes the stereo measurement process and causes the display unit 336 to display the processing result of the stereo measurement. The process returns to S101. On the other hand, when the detected shutter position and the switching instruction indicated by the switching instruction signal are not the same (NO in step S104), the CPU 350 causes the display unit 336 to display a warning of abnormality, and the process returns to step S101. Above, the process of this flowchart is complete | finished.

<Effect>
The shutter position detection processing unit 333 of the measurement apparatus 1 according to the present embodiment detects the switching state of the optical path based on the luminance value of the mask image. Can be detected. For example, the measurement device 1 determines that the shielding operation cannot be normally performed when the left eye image is captured at the timing when the right eye image should be captured. Thereby, since the measuring apparatus 1 can detect that the shielding operation by the shielding member is not properly performed, stereo measurement is performed using an image captured when the shielding operation cannot be performed normally. Therefore, it is possible to prevent erroneous stereo measurement from being performed.

In the present embodiment, the detection unit 332 detects the optical path switching state based on the brightness of the mask image, but the present invention is not limited to this. The detection unit 332 may detect the optical path switching state based on the shape of the mask image. In this case, if the light blocking unit 180 is configured so that the mask image has a special shape that does not exist in the natural world, the subject that exists in the natural world usually does not have such a special shape. The object image and the mask image can be reliably distinguished. As a result, the measuring apparatus 1 can improve the detection accuracy of the switching state of the optical path.
In FIG. 2, as an example, the light blocking unit 180 is configured such that a member that blocks light passing through both optical systems is disposed on the same surface parallel to the imaging unit 190. Members that block light passing through both optical systems may be arranged on different surfaces.

<Modification 1>
Subsequently, Modification 1 of the present embodiment will be described. In the present embodiment, the shutter position detection processing unit 333 detects the position of the shielding member 134 based on a luminance value represented by an image signal corresponding to a predetermined set of detection ranges on the imaging surface. In that case, depending on the condition of the object to be inspected, a local dark image may be applied to the determination region, which may be erroneously determined as a mask portion. Here, the dark image is a dark image formed on the imaging surface when the subject is dark. In order to avoid this or to reduce the probability of erroneous determination, in the first modification, the measurement apparatus 1 provides a plurality of detection ranges in each mask formation region, and the shutter position detection processing unit 333 is configured in advance on the imaging surface. The position of the shielding member 134 is detected based on the luminance value represented by the image signal corresponding to the determined plurality of sets of detection ranges.

  In the first modification, the light blocking unit 180 blocks each of the light on the two optical paths at a plurality of locations, and the detection unit 332 is formed by the light blocking unit 180 blocking a light at a plurality of locations. Based on the mask image, the switching state of the optical path is detected.

  FIG. 14 is a diagram for explaining the processing of the first modification of the present embodiment. Here, it is assumed that the light blocking portion 180 of the first modification is longer in the major axis direction of the mask formation region than the light blocking portion 180 of FIG. On the imaging surface D131 of the imaging unit 190, a dark image R132 and a mask image R133 are shown. In the right eye mask formation region, three detection ranges AR, BR, and CR are set. In the left eye mask formation region, three detection ranges AL, BL, and CL are set.

  In the graph G131 of the same figure, it is a graph which shows an example of the relationship between the position and luminance value of the mask formation area for right eyes contained in the imaging surface D131. Here, the detection value is set to 1 when the luminance is larger than the threshold value, and the detection value is set to 0 when the luminance is equal to or lower than the threshold value. Since the luminance is larger than the threshold in the detection range AR, it is indicated that the detection value is 1. On the other hand, since the luminance is smaller than the threshold value in the detection ranges BR and CR, the detection value is 0.

In the graph G132 of the figure, it is a graph which shows an example of the relationship between the position of the mask formation area for left eyes contained in the imaging surface D131, and a luminance value. Since the luminance is smaller than the threshold value in all the detection ranges, it is indicated that the detection value is 0.
In the example shown in the figure, the shutter position detection processing unit 333 passes through the left-eye optical system 122 since the luminance values represented by the image signals corresponding to all detection ranges included in the left-eye mask formation region are all equal to or less than the threshold value. It can be considered that the light thus formed is imaged on the imaging unit 190. Therefore, the shutter position detection processing unit 333 determines that the shielding member 134 is located at the right eye blocking position where the right eye opening 132 is blocked.

  Accordingly, the shutter position detection processing unit 333 can prevent the dark image from being erroneously detected as a mask image, and thus the shutter position detection processing unit 333 can improve the detection accuracy of the shutter position.

<Modification 2>
Then, the modification 2 of this embodiment is demonstrated. In the second modification, the shutter position detection processing unit 333 provides detection ranges at the four corners of the imaging surface, and determines the position of the shielding member 134 based on luminance values represented by image signals corresponding to the detection ranges at the four corners of the imaging surface. Detect.

  FIG. 15 is a diagram for explaining processing of the second modification of the present embodiment. FIG. 15A shows the shape of the light blocking unit 180 of Modification 2 on a plane parallel to the imaging unit 190 of the light blocking unit 180. This figure is a view seen from the imaging unit 190 side. In FIG. 15A, the imaging surface D140 of the imaging unit 190 is indicated by a dashed square. Since the light blocking unit 180 has such a shape, the light blocking unit 180 blocks the light that has passed through the left-eye optical system 122, so that the mask image is formed at the two left corners of the four corners of the imaging surface D140. Is formed. On the other hand, when the light blocking unit 180 blocks the light that has passed through the right-eye optical system 121, mask images are formed at the two right corners of the four corners of the imaging surface D140.

  FIG. 15B shows a dark image R142, a first mask image R143, and a second mask image R144 on the imaging surface D141 of the imaging unit 190. Detection ranges are provided at the four corners of the imaging surface. Specifically, in the right eye mask formation region, a left corner detection range DR (a square surrounded by a broken line) and a right corner detection range ER (a square surrounded by a broken line) are shown. Also, in the left eye mask formation region, a detection range DL (a square surrounded by a broken line) at the left corner and a detection range EL (a square surrounded by a broken line) at the right corner are shown.

  FIG. 15B shows a first mask image R143 having a triangular shape in the detection range DL, and a second mask image R143 having a triangular shape in the detection range EL. Therefore, in the detection range DL and the detection range EL, the shape of the region whose luminance value is equal to or less than the threshold value is a triangle, and this shape is determined by the shape of the light blocking unit 180. On the other hand, the entire detection range DR is a part of the dark image R142, and most of the detection range ER is a part of the dark image R143. Therefore, the shape of the region whose luminance value is equal to or smaller than the threshold value in the detection range DR is a rectangle, and the shape of the region whose luminance value is equal to or smaller than the threshold value in the detection range ER is a rectangle.

The shutter position detection processing unit 333 detects the switching state of the optical path based on the shape of the area below the threshold in the detection range. That is, the detection unit 332 detects the optical path switching state based on the shape of the mask image.
In the example of FIG. 15B, the shutter position detection processing unit 333 matches the triangle in which the shape of the area below the threshold in the detection range DL and the detection range EL is a shape predetermined by the shape of the light blocking unit 180. Therefore, it can be considered that the light passing through the left-eye optical system 122 forms an image on the imaging unit 190. Therefore, in that case, the shutter position detection processing unit 333 determines that the shielding member 134 is located at the right eye blocking position where the right eye opening 132 is blocked.

  Since the shutter position detection processing unit 333 detects the switching state of the optical path based on the shape of the area below the threshold in the predetermined detection range, the dark image becomes the right eye mask formation area as shown in FIG. Even if most of them are covered, it is possible to prevent a dark image from being erroneously detected as a mask image. Therefore, the shutter position detection processing unit 333 can improve the detection accuracy of the shutter position. In addition, since it is only necessary to block the light collected at the four corners of the imaging surface, the effect that the light blocking unit 180 can block (mask) the light can be reduced.

<Modification 3>
Then, the modification 3 of this embodiment is demonstrated. The measurement apparatus 1 according to the third modification further includes a reference light blocking unit that partially blocks each of the lights on the two optical paths. Then, the detection unit 332 detects the switching state of the optical path based on the mask image and the reference mask image obtained by the reference light blocking unit partially blocking light.

  In the third modification, a reference mask image is provided in the case where the mask luminance as an average value varies according to the change in the external light source, and the shutter position detection processing unit 333 further performs the reference. The switching state of the optical path is detected using a threshold value calculated based on the luminance value of the mask image. The reference mask image is an area in which a mask dark portion is always formed even when the left and right optical systems are switched.

  Since the influence of the external light source acts on both the mask image used for determination and the reference mask image, the shutter position detection processing unit 333 may change the threshold according to the change in the luminance of the reference mask image. The influence of an external light source can be eliminated.

  FIG. 16 is a diagram for explaining the process of the third modification of the present embodiment. In the figure, a reference mask image R151, a mask image R152 imaged in the detection range of the left eye mask formation region, and a normal observation image imaged in the detection range of the right eye mask formation region on the imaging surface D150. R153 is shown.

  A graph G151 in the figure is a graph showing an example of the relationship between the position of the left-eye mask formation region included in the imaging surface D150 and the luminance value. The vertical axis represents the luminance value, and the horizontal axis represents the position in the major axis direction of the left eye mask formation region. It is shown that all the luminance values included in the luminance distribution S151 in the major axis direction of the left eye mask formation region in the detection range are smaller than the threshold value V154. Here, the threshold value V154 is a value obtained by adding a predetermined value α to the luminance value V153 of the reference mask image.

  A graph G152 in the figure is a graph showing an example of the relationship between the position of the right-eye mask formation region included in the imaging surface D150 and the luminance value. The vertical axis represents the luminance value, and the horizontal axis represents the position in the major axis direction of the right eye mask formation region. It is shown that all the luminance values included in the luminance distribution S152 in the major axis direction of the right eye mask formation region in the detection range are larger than the threshold value V154.

  In the example shown in the figure, the shutter position detection processing unit 333 uses the threshold value V154 as a value obtained by adding a predetermined value α to the luminance value V153 of the reference mask image. It can be determined that the luminance value is less than or equal to the threshold value. Therefore, the shutter position detection processing unit 333 can determine that the shielding member 134 is in the right eye shielding position.

  As described above, the shutter position detection processing unit 333 changes the threshold value according to the change in the luminance of the reference mask image, so that even when the luminance of the mask image varies according to the change in the external light source, An appropriate threshold value can be set according to changes in the light source. Therefore, the shutter position detection processing unit 333 can detect the optical path switching state without being affected by the external light source.

  In addition, by recording a program for executing each process of the measurement apparatus 1 of the present embodiment on a computer-readable recording medium, causing the computer system to read and execute the program recorded on the recording medium, You may perform the various process which concerns on the measuring device 1 mentioned above.

  Here, the “computer system” may include an OS and hardware such as peripheral devices. Further, the “computer system” includes a homepage providing environment (or display environment) if a WWW system is used. The “computer-readable recording medium” means a flexible disk, a magneto-optical disk, a ROM, a writable nonvolatile memory such as a flash memory, a portable medium such as a CD-ROM, a hard disk built in a computer system, etc. This is a storage device.

  Further, the “computer-readable recording medium” refers to a volatile memory (for example, DRAM (Dynamic) in a computer system serving as a server or a client when a program is transmitted via a network such as the Internet or a communication line such as a telephone line. Random Access Memory)) that holds a program for a certain period of time is also included. The program may be transmitted from a computer system storing the program in a storage device or the like to another computer system via a transmission medium or by a transmission wave in the transmission medium. Here, the “transmission medium” for transmitting the program refers to a medium having a function of transmitting information, such as a network (communication network) such as the Internet or a communication line (communication line) such as a telephone line. The program may be for realizing a part of the functions described above. Furthermore, what can implement | achieve the function mentioned above in combination with the program already recorded on the computer system, what is called a difference file (difference program) may be sufficient.

  As mentioned above, although embodiment of this invention was explained in full detail with reference to drawings, the concrete structure is not restricted to this embodiment, The design etc. of the range which does not deviate from the summary of this invention are included.

DESCRIPTION OF SYMBOLS 1 Measurement apparatus 100 Insertion part 110 1st cover glass 120 2 optical path formation optical system 130 Optical path switching part 140 Correction | amendment optical system 150 2nd cover glass 160 Imaging optical system 170 3rd cover glass 180 Light block part 190 Imaging part DESCRIPTION OF SYMBOLS 200 Operation part 300 Main part 310 CCD signal processing circuit 320 Shutter drive circuit 330 Image signal processing circuit 331 Image memory 332 Detection part 333 Shutter position detection processing part 334 Image adjustment processing part 335 GUI composition processing part 336 Display part 340 Memory 350 CPU
351 Switching instruction unit 352 Determination unit 353 Stereo measurement processing unit 337 Image recording circuit 360 Operation unit circuit 370 Power supply circuit 380 LED drive circuit

Claims (16)

A two-optical path forming optical system that forms two optical paths with parallax;
An optical path switching unit that switches two optical paths formed by the two optical path forming optical system in a time-sharing manner;
Of the two optical paths, a position where the first light is partially blocked on a plane perpendicular to the direction in which the first light passing through the first optical path travels, and the second of the two optical paths that passes through the second optical path. A light blocking part for partially blocking each of the first light and the second light, so that a position where the second light is partially blocked in a plane perpendicular to a direction in which the second light travels,
An imaging optical system that forms a mask image based on the light partially blocked by the light blocking unit;
An imaging unit that captures a mask image formed by the imaging optical system;
A detection unit that detects a switching state of the optical path based on a mask image obtained by the imaging unit capturing a mask image;
A measuring device comprising:   The measurement device according to claim 1, wherein the detection unit detects a switching state of an optical path based on a luminance of the mask image.   The measurement device according to claim 1, wherein the detection unit detects a switching state of an optical path based on a shape of the mask image.   The measurement device according to claim 1, wherein the detection unit detects a switching state of an optical path based on a position of the mask image.   The detection unit applies a filter that allows a signal having a predetermined spatial frequency or less to pass through the luminance of the mask image, and detects an optical path switching state based on the luminance after the filter is applied. 2. The measuring device according to 2. The light blocking unit blocks the light on the two optical paths at a plurality of locations,
The said detection part detects the switching state of an optical path based on the several mask image formed when the said light shielding part interrupts | blocks light in multiple places. The measuring device described. A reference light blocking unit that partially blocks each of the lights on the two optical paths;
7. The detection unit according to claim 1, wherein the detection unit detects an optical path switching state based on the mask image and a reference mask image obtained when the reference light blocking unit partially blocks light. The measuring device according to any one of the above. A switching instruction unit that instructs the optical path switching unit to switch an optical path;
The measurement according to any one of claims 1 to 7, further comprising a determination unit that determines whether or not the switching state detected by the detection unit matches a switching instruction signal indicating an instruction given by the switching instruction unit. apparatus.   The measurement device according to claim 8, wherein the determination unit performs stereo measurement processing by a stereo measurement processing unit when it is determined to be matched, and prohibits stereo measurement processing by the stereo measurement processing unit when it is determined that they are not matched. The optical path switching unit includes one aperture member having a first opening and a second opening arranged corresponding to the two optical paths, the first opening, and the second opening. With a shielding member that can be alternately shielded by time division,
2. The shielding member starts to shield the second opening after transitioning from a state in which the first opening is completely shielded to a state in which the first opening is not partially shielded. To 9. The measuring device according to any one of claims 9 to 9. The optical path switching unit includes one aperture member having a first opening and a second opening arranged corresponding to the two optical paths, the first opening, and the second opening. With a shielding member that can be alternately shielded by time division,
The center of the shielding member moves along an axis passing through the center of the first opening and the center of the second opening, and the length of the shielding member along the axis is along the axis. The opening length of the first opening and the opening length of the second opening along the axis are longer than the outer edge of the first opening and the outer edge of the second opening. The distance along the axis is equal to or less than a length obtained by adding to the opening length of the first opening, and is equal to or less than a length obtained by adding the distance to the opening length of the second opening. The measuring device according to any one of the above. The imaging optical system includes an imaging lens for imaging,
The measuring device according to claim 1, wherein the light blocking unit is located between the imaging unit and an imaging lens positioned closest to the imaging unit. The two optical path forming optical system and the one optical path forming optical system forming one optical path are configured to be interchangeable,
13. The apparatus according to claim 12, wherein when the one optical path forming optical system is attached, the light blocking unit is located at a position where light on the optical path formed by the one optical path forming optical system is not blocked.   The measuring device according to claim 1, wherein the light blocking unit is positioned on the front of the optical path with respect to the two optical path forming optical system.   The measurement apparatus according to claim 1, wherein the mask image is formed in an invalid pixel region on an imaging surface of the imaging unit. Two optical path forming optical systems that form two optical paths with parallax, an optical path switching unit that switches the two optical paths formed by the two optical path forming optical systems in a time-division manner, and the first optical path of the two optical paths. A position where the first light is partially blocked in a plane perpendicular to the direction in which the first light travels, and a plane perpendicular to the direction in which the second light passing through the second optical path travels out of the two optical paths. Based on the light blocking part that partially blocks each of the first light and the second light, and the light that is partially blocked by the light blocking part so that the position where the second light is partially blocked is different. An imaging optical system that forms a mask image, and an imaging device that captures a mask image formed by the imaging optical system,
The program for performing the step which detects the switching state of an optical path based on the mask image obtained when the said imaging part imaged a mask image.

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