JP2007316432A - Enlarging observation device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an enlarging observation device which can be comparatively easily focused on an observation area set in a photographed image. <P>SOLUTION: A control part calculates a focus value concurrently with moving processing for an imaging part submissive to operation from a user. The control part extracts a maximum focus value at which the degree of focus becomes maximum out of the calculated focus values, and stores a Z-axis position corresponding to the extracted maximum focus value. Furthermore, the control part displays present position display 62 showing the present Z-axis position, and maximum focus position display 66 showing the maximum focus position on a graph where predetermined scale spaces are put. When the user selects (clicks) the display area of the maximum focus position display 66, the control part determines it as the input of a focus instruction and moves the imaging part to the maximum focus position. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a magnifying observation device that magnifies and displays an image of a photographed object, and more particularly to a technique for supporting a focus operation on an observation region in an image.

  In manufacturing sites and research facilities, instead of conventional microscopes, magnification observation devices are becoming popular. The magnifying observation apparatus is an apparatus that shoots an image by enlarging an object and displays the captured image. Such a magnifying observation device has advantages such as a longer subject distance, a large number of users observing an enlarged image at the same time, and recording as digital information, as compared with a conventional microscope.

  As one form of such a magnifying observation apparatus, a configuration including a sample stage arranged on a horizontal plane and an imaging unit arranged so as to be movable in the vertical direction of the sample stage is often adopted. According to the magnifying observation apparatus according to this configuration, the subject distance to the object arranged on the sample stage can be changed with the movement of the imaging unit.

For example, Japanese Patent Laid-Open No. 2000-39566 (Patent Document 1) discloses an imaging unit that captures an optically magnified image, and a movement positioning control unit that moves and positions the optical magnifying unit to an arbitrary relative position with respect to an observation object. And a magnifying observation device. According to this magnifying observation apparatus, the microscope barrel can be moved to an arbitrary position in the Z-axis direction by the Z-axis feed mechanism contained in the column. It is disclosed that such a Z-axis feed mechanism includes an electric motor and a feed screw.
JP 2000-39566 A

  The main application of the magnification observation apparatus as described above is to shoot an arbitrary object and display the enlarged image. For this reason, the Z-axis feed mechanism as disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 2000-39566 (Patent Document 1) is often configured to be arbitrarily operated by a user operation. For example, the imaging unit is configured to be arbitrarily movable in response to an operation of an input device (such as a mouse) by the user.

  By the way, in many magnifying observation apparatuses, an object is magnified and photographed at a high magnification. Therefore, a range in the Z-axis direction in which the imaging unit can focus (hereinafter also referred to as “focus”), That is, the depth of field (DOF) is very shallow. Therefore, in order to focus on a region desired by the user, it is necessary to precisely move the imaging unit, but it is often difficult to perform such precise movement by an operation of a mouse or the like.

  Therefore, the user has to find a position with the highest degree of focus by trial and error. As a result, there is a problem that the efficiency of the observation work is reduced.

  Accordingly, the present invention has been made to solve such a problem, and an object of the present invention is to provide a magnification observation apparatus that can relatively easily obtain a focus on an observation region set in a captured image. It is to be.

  According to the present invention, an imaging unit for photographing an object, a display unit for displaying an image photographed by the imaging unit, and a focus capable of changing a cross-sectional height of the object focused by the imaging unit The height change means, the state value acquisition means for acquiring the state value corresponding to the cross-sectional height changed by the focus height change means, and the imaging unit for the observation region set in the image captured by the imaging unit A focus value calculation unit that calculates a focus value indicating the degree of focus by the camera, and a maximum focus value that maximizes the focus degree is extracted from the focus values calculated by the focus value calculation unit and corresponds to the maximum focus value A focus value evaluation unit that stores a state value to be received and a focus value evaluation unit in response to a focus instruction from the outside. Such that the state value storage Te is an enlarged observation device and a focus control means for controlling the focus height changing means.

  According to this invention, the focus height changing unit changes the cross-sectional height of the object focused by the imaging unit, and calculates the focus value for the observation region. Of the calculated focus values, the maximum focus value that maximizes the degree of focus is extracted, and the state value corresponding to the extracted maximum focus value is stored. Further, when a focus instruction is given, the focus height changing means is controlled so that the state value corresponding to the maximum focus value is obtained. For this reason, the degree of focus can be maximized for the observation region simply by giving a focus instruction.

  Preferably, the focus height changing means is controlled to operate according to an operation instruction from the outside.

  More preferably, the focus value evaluation unit extracts the maximum focus value within a range in which the focus height changing unit is actually operated according to the operation instruction.

  More preferably, the focus value evaluation means determines the extreme value of the focus value that changes with the operation of the focus height changing means as the maximum focus value.

  More preferably, the focus value evaluation means determines the extreme value having the maximum absolute value among the plurality of extreme values as the maximum focus value.

  Preferably, the focus value evaluation unit causes the display unit to display a change characteristic of the focus value associated with the operation of the focus height changing unit in association with the state value in the focus height changing unit.

  More preferably, the focus value evaluation means displays the change characteristic of the focus value on the display unit together with the corresponding maximum focus value.

  Preferably, the focus value evaluation unit causes the display unit to display a current state value in the focus height changing unit and a state value corresponding to the maximum focus value.

  More preferably, the focus height changing unit is configured to be provided with an operation instruction via an operation instruction screen displayed on the display unit, and the operation instruction screen is a current state value displayed by the focus value evaluation unit. And an operation instruction can be input in association with the relative relationship between the state value corresponding to the maximum focus value.

  More preferably, the operation instruction screen is configured to be able to input a focus instruction in association with a display area of a state value corresponding to the maximum focus value.

  Preferably, the observation area is configured to be changeable according to an area setting instruction from the outside.

  Preferably, the focus value calculation unit calculates a focus value for each of the plurality of observation regions, and the focus value evaluation unit calculates the corresponding observation region based on each of the focus values calculated by the focus value calculation unit. Extracts the maximum focus value at.

  According to the present invention, it is possible to realize a magnifying observation apparatus that can relatively easily obtain a focus on an observation region set in a captured image.

  Embodiments of the present invention will be described in detail with reference to the drawings. Note that the same or corresponding parts in the drawings are denoted by the same reference numerals and description thereof will not be repeated.

FIG. 1 is a schematic configuration diagram of a magnification observation apparatus 100 according to an embodiment of the present invention.
Referring to FIG. 1, a magnifying observation apparatus 100 is an apparatus that magnifies and displays a captured image of an object, and includes an imaging mechanism 2, a main body unit 4, a display unit 6, and an input unit 8.

  The imaging mechanism 2 includes an imaging unit 12 for capturing an object and an imaging drive unit 14 for changing a subject distance from the imaging unit 12 to the object.

  The imaging unit 12 includes an optical system such as a lens and an imaging device such as a CCD (Charge Coupled Devices), and outputs a video signal corresponding to light received from an object to the main body unit 4.

  The imaging drive unit 14 corresponds to a focus height changing unit that can change the cross-sectional height of the object focused by the imaging unit 12, and the imaging unit 12 is set in accordance with a drive command received from the main body unit 4. Move along the direction. Further, the imaging drive unit 14 outputs position information corresponding to the position of the imaging unit 12 to the main body unit 4.

  The main body 4 includes an I / F unit 16, a control unit 18, a memory 20, and an I / O control unit 22.

  The I / F unit 16 is electrically connected to the imaging unit 12 and the imaging driving unit 14 that constitute the imaging mechanism 2, and transmits a video signal output from the imaging unit 12 to the control unit 18, and from the control unit 18. The output drive command is transmitted to the imaging drive unit 14. Further, the I / F unit 16 transmits the position information output from the imaging drive unit 14 to the control unit 18.

  The control unit 18 is configured by an arithmetic device such as a CPU (Central Processing Unit). Then, the control unit 18 outputs an image of the object photographed by the imaging unit 12 to the display unit 6 via the I / O control unit 22 and also according to an operation instruction from the user given via the input unit 8. The imaging drive unit 14 is controlled. Further, the control unit 18 acquires the position of the imaging unit 12 based on the position information output from the imaging drive unit 14.

  The memory 20 stores a program executed by the control unit 18, image data stored by the control unit 18, work data associated with program execution of the control unit 18, various setting data given by a user and the like.

  The I / O control unit 22 is electrically connected to the display unit 6, the input unit 8, and the like, and displays an enlarged image captured by the imaging unit 12, an MMI (Man Machine Interface) screen generated by the control unit 18, and the like. Output to the display unit 6. In addition, the I / O control unit 22 receives an operation instruction corresponding to a user operation from the input unit 8 and transmits the operation instruction to the control unit 18.

  The display unit 6 includes, for example, a liquid crystal display (LCD), a plasma display, and an organic EL (Electro Luminescence) display, and displays an image output via the I / O control unit 22 on its display surface. To do. In the present embodiment, the display unit 6 is configured integrally with the main body unit 4.

FIG. 2 is a diagram showing an example of the appearance of main body 4 and display 6 according to the present embodiment.
Referring to FIG. 2, main body 4 is formed in a box shape, while display 6 is configured to be slidable on the upper surface of main body 4. That is, the display unit 6 is fixed so as to have an arbitrary angle with respect to the upper surface of the main body unit 4 when the magnification observation device 100 is used, and the display unit 6 is not used when the magnification observation device 100 is not used. It is parallel to the upper surface and fixed so as to be stored integrally. With such a configuration, the magnifying observation apparatus 100 according to the present embodiment can realize easy portability and space saving.

  Referring to FIG. 1 again, input unit 8 includes a keyboard, a mouse, and the like, accepts an operation instruction from the user, and outputs the operation instruction to main unit 4. Furthermore, as an example of the input unit 8, a touch panel formed on the display surface of the display unit 6 may be used.

(Imaging mechanism)
FIG. 3 is an example of a side view of imaging mechanism 2 according to the present embodiment.

  With reference to FIG. 3, the imaging mechanism 2 further includes a sample stage 32, a stand 34, a stand engaging member 36, and an imaging unit fixing member 38. An object is arranged on the sample stage 32, and the object is photographed by the imaging unit 12 arranged to be movable in the vertical direction of the object. In the following description, the moving direction of the imaging unit 12 is also referred to as “Z-axis direction”, and the position of the imaging unit 12 in the Z-axis direction is also referred to as “Z-axis position”.

  Focusing by the imaging unit 12 is possible with respect to the cross-sectional height at which the distance from the imaging unit 12 matches the focal length, but this focal length has a width depending on the optical system of the imaging unit 12. The width of such a focal length is the depth of field, which means the size of the range in which the imaging unit 12 can focus. In particular, in the magnifying observation apparatus 100 that magnifies and displays an object, the imaging unit 12 magnifies the object to a very high magnification, so that the depth of field is inevitably shallow.

  Therefore, when the size (height) of the target in the Z-axis direction is larger than the depth of field of the imaging unit 12, only a partial region of the target is focused on the display unit 6. The displayed image is displayed. Therefore, the sectional height of the object focused by the imaging unit 12 can be changed by moving the imaging unit 12 in the Z-axis direction by a minute distance suitable for the depth of field.

  The stand 34 is disposed so as to extend in the vertical direction of the sample stage 32, and forms a path for the imaging unit 12 to move in the Z-axis direction.

  The stand engaging member 36 is configured to be movable along the stand 34 and to be fixed at a position (height) desired by the user. Specifically, it can be moved and fixed by a dial or a lever constituting the stand engaging member 36.

  The imaging unit fixing member 38 is connected to the imaging unit 12 on one surface thereof, and fixes the imaging unit 12. Further, the stand engaging member 36 and the imaging unit fixing member 38 are mechanically engaged with each other via, for example, a feed screw, and the feed screw is connected to the imaging drive unit 14. The relative position between the stand engaging member 36 and the imaging unit fixing member 38 changes along the stand 34 by the rotational driving force output by the imaging drive unit 14.

  As a result, the imaging unit 12 connected to the imaging unit fixing member 38 moves in the Z-axis direction, and the subject distance from the imaging unit 12 to the object changes.

  As an example, the imaging drive unit 14 includes a stepping motor, a driver unit for driving the stepping motor, and the like, and can generate a rotational displacement in accordance with a drive command given from the control unit 18. That is, since the stepping motor can be configured to rotate by 120 ° (electrical angle) with one drive pulse, for example, control is performed so that a number of drive pulses corresponding to the desired subject distance displacement amount is applied to the stepping motor. What is necessary is just to comprise a system | strain and the position control of the imaging part 12 is realizable comparatively easily. Then, the imaging drive unit 14 outputs position information corresponding to the position of the imaging unit 12 to the control unit 18.

(Focus operation)
FIG. 4 is a diagram illustrating an example of display on the display unit 6. FIG. 4 shows an image obtained by photographing a pin portion of an IC (Integrated Circuit).

FIG. 4A is a diagram illustrating a state where the right portion of the image is focused.
FIG. 4B is a diagram illustrating a state where the central portion of the image is focused.

FIG. 4C is a diagram illustrating a state in which the left portion of the image is focused.
4A to 4C, when the depth of field of the imaging unit 12 is shallower than the size of the target in the Z-axis direction, a partial region of the target Since only the image is focused, the user moves the imaging unit 12 in the Z-axis direction so as to focus on a desired observation region in the captured image. Specifically, the user gives a desired operation instruction to the operation instruction screen 40 displayed on the display unit 6 by the control unit 18 via the input unit 8 (for example, a mouse).

  4A to 4C, the state where the imaging unit 12 is closest to the object is FIG. 4A, and the state where the imaging unit 12 is farthest from the object is FIG. (C).

FIG. 5 is a diagram for explaining the operation instruction screen 40.
FIG. 5A shows a state in which no operation is performed by the user.

FIG. 5B shows a state after the maximum focus position display 66 is selected.
Referring to FIG. 5A, an operation instruction input area 50 and a state value display area 60 are arranged on the operation instruction screen 40.

  In the operation instruction input area 50, an operation instruction lever 52 capable of inputting an operation instruction for moving the imaging drive unit 14 is disposed. Specifically, when the user makes the pointer PNT coincide with the operation instruction lever 52 and moves (drags) in the desired direction while selecting (clicking), the control unit 18 displaces the operation instruction lever 52 on the screen. The imaging unit 12 is moved in the Z-axis direction at a speed according to the above. From the viewpoint of user friendliness, the operation instruction input area 50 is provided with a plurality of arrows “Δ” and “▽” indicating the moving direction and speed of the imaging unit 12.

  Further, in the present embodiment, when the user cancels the selection of the operation instruction lever 52, the operation instruction lever 52 is returned to a neutral state (a state in which no operation instruction is given).

  In addition to the operation instruction lever 52, operation instruction buttons 54u and 54d capable of inputting operation instructions are further arranged on the operation instruction screen 40. The operation instruction buttons 54u and 54d are operation buttons for moving the imaging drive unit 14 upward and downward along the Z-axis direction, respectively, and are used to move the imaging drive unit 14 by a minute distance. That is, when the operation instruction button 54u or 54d is selected (clicked), the control unit 18 gives the imaging drive unit 14 a drive command for moving a predetermined minute distance for each selection.

  Therefore, the user can coarsely adjust the position of the imaging unit 12 using the operation instruction lever 52 and finely adjust the position of the imaging unit 12 using the operation instruction buttons 54u and 54d.

  However, when the depth of field of the imaging unit 12 is shallow, or when the moving speed of the imaging unit 12 is fast, the user looks at which Z-axis position the desired observation area is most focused on. It is difficult to judge. In such a case, the user must repeat the operation of the operation instruction lever 52 or the operation instruction buttons 54u and 54d and find a position with the highest degree of focus by trial and error. The control unit 18 assists the user in focusing on such an observation area.

(Focus control)
As shown in FIGS. 4A to 4C, the user sets a desired observation area FA in advance in an image photographed by the imaging unit 12. Note that the observation area FA can be set, for example, by selection (clicking) and movement (dragging) using the pointer PNT. And the control part 18 calculates the focus value which shows the degree of the focus by the imaging part 12 by the method mentioned later about the observation area | region FA to set. Here, the control unit 18 calculates the focus value in parallel with the movement process of the imaging unit 12 according to the operation from the user. For this reason, the focus value continuously changes as the imaging unit 12 moves, that is, according to the Z-axis position of the imaging unit 12.

  The control unit 18 extracts the maximum focus value that maximizes the degree of focus from the calculated focus values, and stores the Z-axis position (corresponding to the state value) corresponding to the extracted maximum focus value in the memory 20. .

  Then, the control unit 18 controls the imaging drive unit 14 so as to realize the state value stored in the memory 20 in response to the focus instruction from the user. That is, in response to the focus instruction from the user, the control unit 18 moves the imaging unit 12 to the Z-axis position (hereinafter also referred to as “maximum focus position”) corresponding to the extracted maximum focus value.

  Referring to FIG. 5A again, the control unit 18 displays a state value display area 60 indicating the current Z-axis position of the imaging drive unit 14 and the maximum focus position. That is, the control unit 18 displays a current position display 62 indicating the current Z-axis position and a maximum focus position display 66 (“F1”) indicating the maximum focus position on a graph in which a predetermined scale interval is engraved. To do. The control unit 18 generates the state value display area 60 so that the current position display 62 is always arranged at the center of the state value display area 60.

  The maximum focus position display 66 is configured so that a focus instruction can be input. That is, when the user selects (clicks) the display area of the maximum focus position display 66, the control unit 18 determines that the focus instruction is input, and moves the imaging unit 12 to the maximum focus position. Then, an image in which the observation area FA is focused is displayed on the display unit 6 as shown in FIG.

  Further, on the operation instruction screen 40, as shown in FIG. 5B, the maximum focus position display 66 is displayed at a position coincident with the current position display 62, and the user is notified that the imaging unit 12 has moved to the maximum focus position. .

  As described above, the user can focus the desired observation region only by selecting (clicking) the maximum focus position display 66 automatically displayed by the control unit 18. In this way, the user can obtain the focus of the observation area with one operation, and thus the efficiency of the observation work can be dramatically increased.

(User-friendly function on the operation instruction screen)
Referring to FIG. 5A again, in addition to the current position display 62 and the maximum focus position display 66, the control unit 18 displays a zero position display 64 (“0”) and a reference point display 68 on a common graph. ("BL") is displayed. The zero position display 64 indicates the position of a zero point that serves as a reference for defining the Z-axis position of the imaging unit 12. The reference point display 68 indicates a reference point for the user to monitor and measure the amount of movement of the imaging unit 12 in the Z-axis direction. This reference point is provided from the viewpoint of user friendliness and can be set at an arbitrary position by a user operation.

  Note that the graph display range in the state value display region 60 is more user-friendly to be determined according to the depth of field of the imaging unit 12. Therefore, the control unit 18 acquires the depth of field based on the preset lens configuration and lens magnification of the imaging unit 12, and corresponds to a predetermined multiple (for example, four times) of the acquired depth of field. The state value display area 60 is displayed so as to be in the graph range.

  In the operation instruction screen 40, an operation instruction lever 52 and operation instruction buttons 54u and 54d are arranged in correspondence with the relative relationship between the current Z-axis position of the imaging unit 12 and the maximum focus position. That is, on the operation instruction screen 40, the direction of operation by the operation instruction lever 52 or the operation instruction buttons 54u and 54d corresponds to the positional relationship between the current position display 62 and the maximum focus position display 66. Therefore, the user can know at a glance whether the user can indicate the operation in which direction from the current Z-axis position to approach the maximum focus position.

FIG. 6 is a diagram for explaining an operation related to the operation of the operation instruction lever 52.
With reference to FIG. 6, as an example, when the user moves (drags) the operation instruction lever 52 downward, the control unit 18 controls the imaging unit 12 to move downward in the Z axis. Then, as the imaging unit 12 moves, the control unit 18 changes the display positions of the maximum focus position display 66, the zero position display 64, and the reference point display 68 in the upward direction on the paper. In the example of FIG. 6, since the reference point display 68 is outside the range of the graph displayed in the state value display area 60 even after the imaging unit 12 is moved, the display position is not changed.

  Therefore, the user can confirm the actual positional relationship of the imaging unit 12 in the Z-axis direction at a glance by looking on the display unit 6.

(Calculation of focus value)
Various methods can be employed to calculate the focus value indicating the degree of focus. As an example, a method of calculating based on the intensity of the RGB signal is used.

FIG. 7 is a diagram for explaining the calculation principle of the focus value.
Referring to FIG. 7, control unit 18 focuses on one value (for example, a green tint value) among RGB values that define each pixel of observation area FA set in a captured image. In the following, the green shade value arranged in association with the observation area FA (n pixels × m pixels) is expressed as Gij (1 ≦ i ≦ n, 1 ≦ j ≦ m).

  Then, as an example, the control unit 18 sequentially calculates the density difference d (absolute value) between pixels adjacent in the horizontal direction, and cumulatively adds the calculated density difference. In general, if the degree of focus of the observation area FA is high, the contrast (shading difference) of the entire image becomes strong, so that the shading difference becomes relatively large. On the other hand, if the degree of focus in the observation area FA is low, the entire image is blurred and the contrast is weakened, so that the difference in density is relatively small.

  Therefore, the control unit 18 uses the accumulated addition value of the light and shade differences as the focus value F indicating the focus degree. Specifically, the control unit 18 calculates the focus value F every predetermined cycle (for example, several hundreds msec) according to the following formula.

Focus value F = Σdij (2 ≦ i ≦ n, 1 ≦ j ≦ m)
= Σ | Gij−Gkj | (1 ≦ i ≦ n−1, 1 ≦ j ≦ m, k = i + 1)
In the present embodiment, the focus value is calculated by accumulatively adding the absolute values of the light and shade differences as in the above equation, so that the focus value increases as the focus degree increases.

  In calculating the focus value, a red shade value or a blue shade value may be used, and a color difference vector (a vector defined by the shade difference of each color) of adjacent pixel values may be used.

(Extraction of maximum focus value)
As described above, the control unit 18 extracts the maximum focus value Fmax that maximizes the degree of focus from the focus values F calculated every predetermined period.

  In particular, in the present embodiment, the control unit 18 extracts the maximum focus value within the range in which the imaging drive unit 14 is actually operated according to the operation by the user. This is because the operation range of the imaging drive unit 14 corresponds to a range that the user considers necessary for observation, and it is considered that it is more efficient to extract the maximum focus value only within the range.

FIG. 8 shows an example of a change in the focus value F accompanying the movement of the imaging unit 12 in the Z-axis direction.
FIG. 8A shows a case where the focus value F monotonously increases within the movement range.

FIG. 8B shows a case where the focus value F has an inflection point within the movement range.
With reference to Fig.8 (a), the control part 18 operates the imaging drive part 14 according to the operation instruction from a user. With the operation of the imaging drive unit 14, the imaging unit 12 moves in the Z-axis direction, and the calculated focus value F also changes.

  Therefore, each time the focus value F is calculated, the control unit 18 compares the calculated focus value F with the maximum focus value Fmax that has been extracted up to that point in time, so that the maximum focus value Fmax is updated. Update to the value of. Therefore, when the focus value F monotonously increases within the movement range of the imaging unit 12, the focus value F at the final position of the movement range corresponds to the maximum focus value Fmax.

  Note that, as described above, the control unit 18 extracts the maximum focus value Fmax only within the movement range of the imaging unit 12, so that it is extracted even if there is a position where a larger focus value F exists outside the movement range. do not do.

  Further, instead of the configuration in which the calculated focus value F is compared every time the focus value F is calculated, the change characteristic of the focus value F that occurs with a series of movements of the imaging unit 12 is temporarily stored. Based on the change characteristic of the focus value F, the maximum focus value Fmax may be extracted.

  Referring to FIG. 8B, when the inflection point T is included in the change characteristic of the focus value F that occurs with the series of movements of the imaging unit 12, the control unit 18 performs the movement after the movement is completed. The extreme value is detected from the stored change characteristics of the focus value F, and the extreme value is determined as the maximum focus value Fmax.

  Further, when a plurality of inflection points T are included in the change characteristic of the focus value F that is generated along with the movement of the example, the extreme value having the maximum absolute value is determined as the maximum focus value Fmax.

  Further, as shown in FIGS. 8A and 8B, the control unit 18 can also display a graph in which the change characteristic of the focus value F is associated with the Z-axis position on the display unit 6. When displaying such a graph, the numerical value VAL (FIG. 8A and FIG. 8B) of the maximum focus value Fmax may be displayed simultaneously.

(Processing flow)
FIG. 9 is a flowchart showing an outline of processing according to the present embodiment.

  Referring to FIG. 9, the control unit 18 acquires the current Z-axis position Pz of the imaging unit 12 based on the position information from the imaging drive unit 14 (step S100). And the control part 18 acquires the depth of field of the imaging part 12, and determines the graph display range of the state value display area 60 (step S102). Further, the control unit 18 initializes the maximum focus value Fmax and the maximum focus position Pzmax (Fmax = 0 and Pzmax = 0) (step S104). Thereafter, the control unit 18 displays the operation instruction screen 40 on the display unit 6 (step S106).

  After the operation instruction screen 40 is displayed, the control unit 18 determines whether or not a focus instruction has been input (step S108). That is, the control unit 18 determines whether or not the maximum focus position display 66 on the operation instruction screen 40 has been selected.

  When the focus instruction is input (YES in step S108), the control unit 18 gives a drive command to the image pickup drive unit 14 so as to move the image pickup unit 12 to the maximum focus position Pzmax (step S110). . When the imaging unit 12 moves to the maximum focus position Pzmax, the control unit 18 repeatedly executes the processes after step S108.

  If the focus instruction has not been input (NO in step S108), the control unit 18 determines whether the movement of the imaging unit 12 has been instructed (step S112). That is, the control unit 18 determines whether or not the operation instruction lever 52 or the operation instruction buttons 54u and 54d are operated by the user.

  When the movement of the imaging unit 12 is instructed (YES in step S112), the control unit 18 gives a driving command corresponding to the input instruction to the imaging driving unit 14 (step S114).

  When the movement of the imaging unit 12 is not instructed (NO in step S112), the control unit 18 determines whether or not the imaging unit 12 is moving (step S116).

  After giving a drive command corresponding to the input instruction to the imaging drive unit 14 (after step S114), or when the imaging unit 12 is moving (YES in step S116), the control unit 18 The focus value F of the observation area FA is calculated (step S118), and the current Z-axis position Pz of the imaging unit 12 is acquired based on the position information from the imaging drive unit 14 (step S120). Subsequently, the control unit 18 determines whether or not the calculated focus value F exceeds the current maximum focus value Fmax (step S122).

  When the calculated focus value F exceeds the current maximum focus value Fmax (YES in step S122), the control unit 18 updates the maximum focus value Fmax to the current focus value F, and at the maximum focus position. Pzmax is updated to the current Z-axis position Pz (step S124).

  After updating the maximum focus value Fmax and the maximum focus position Pzmax (after step S124), or when the calculated focus value F does not exceed the current maximum focus value Fmax (NO in step S122), the control unit 18 Determines again whether the movement of the imaging unit 12 has been instructed (step S112).

  When the imaging unit 12 is not moving (NO in step S116), the control unit 18 determines whether or not the end of the operation instruction screen 40 is instructed (step S126). When the end of the operation instruction screen 40 is instructed (YES in step S126), the control unit 18 ends the display of the operation instruction screen 40 and ends the process.

  When the end of the operation instruction screen 40 is not instructed (NO in step S126), the control unit 18 repeatedly executes the processing from step S108.

  In step S122 described above, the focus value may be treated as valid only when the calculated focus value F exceeds a predetermined threshold value. In other words, since there is a possibility of noise when the focus value is small, in order to increase the reliability, the focus value below a predetermined threshold value may be ignored.

(Modification 1)
In the above-described embodiment, the aspect of displaying the positional relationship between the current Z-axis position and the maximum focus position on the common graph has been described. However, the degree of focus (focus value) is visually expressed. Thus, the visibility of the user can be further improved.

  FIG. 10 is a diagram for describing an operation instruction screen 40 # according to the first modification of the present embodiment.

  Referring to FIG. 10, operation instruction screen 40 # is obtained by arranging focus value display area 70 in place of state value display area 60 in operation instruction screen 40 shown in FIG.

  The focus value display area 70 includes a visualization display area 72. In the visualization display area 72, image display based on the focus value (for example, pseudo color display or pseudo gray display) is performed in association with the Z-axis position.

  In the pseudo color display, each focus value is converted into a corresponding color on a hue map and displayed. Specifically, the control unit 18 normalizes each focus value acquired in association with the Z-axis position (for example, 0 to 255 digits), and then assigns it to the corresponding Z-axis position with reference to the hue map. Determine the color. In such pseudo color display, for example, “red” indicates a high focus value, while “blue” indicates a low focus value.

  The pseudo gradation display is to display each focus value as a gradation (gray scale). Specifically, the control unit 18 normalizes each focus value acquired in association with the Z-axis position (for example, 0 to 255 digits), and then determines the shade to be allocated to the corresponding Z-axis position. In such pseudo gray display, “white” indicates a high focus value, while “black” indicates a low focus value.

  As described above, the user can grasp the correspondence between the focus value and the Z-axis position at a glance.

  Also in the first modification of the present embodiment, the user can input a focus instruction. As an example, when the user selects (clicks) any position in the visualization display area 72, the control unit 18 determines that a focus instruction is input, and moves the imaging unit 12 to the maximum focus position.

  The focus value display area 70 includes a current position display 74 (“C”) indicating the current Z-axis position of the imaging unit 12 and a reference point for the user to monitor and measure the amount of movement in the Z-axis direction. A display 76 (“BL”) is arranged.

  Since the others are the same as those of the operation instruction screen 40 described above, detailed description will not be repeated.

(Modification 2)
In the above-described embodiment, the case where one observation area FA is set in an image photographed by the imaging unit 12 is illustrated, but a plurality of observation areas may be set.

  FIG. 11 is a diagram illustrating an example when two observation areas FA1 and FA2 are set. Note that the object of the image shown in FIG. 11 is the same as the object of the image shown in FIG.

  FIG. 11A is a diagram illustrating a state after a focus instruction is given to the observation area FA2.

  FIG. 11B is a diagram illustrating a state where the user has moved the imaging unit 12 to an arbitrary Z-axis position.

  FIG. 11C is a diagram showing a state after the focus instruction for the observation area FA1 is given.

  The control unit 18 calculates a focus value for each of the two observation areas FA1 and FA2, and further extracts a maximum focus value in the observation areas FA1 and FA2 based on each of the calculated focus values. Specifically, the control unit 18 independently performs the same process as the process for the observation area FA described above for each of the observation areas FA1 and FA2.

  FIG. 12 is a diagram for explaining a display example of the operation instruction screen 40 according to the second modification of the present embodiment.

  Referring to FIG. 12, when two observation areas FA1 and FA2 are set, the operation instruction screen 40 displays a maximum focus position display 66a (“F1”) indicating the Z-axis position at each maximum focus value. And 66b ("F2") are displayed. The maximum focus position displays 66a and 66b are configured so that a corresponding focus instruction can be input. That is, when the user selects (clicks) the display area of the maximum focus position display 66a, the control unit 18 moves the imaging unit 12 to the maximum focus position in the observation area FA1, as shown in FIG. When the user selects (clicks) the display area of the maximum focus position display 66b, the control unit 18 moves the imaging unit 12 to the maximum focus position in the observation area FA2, as shown in FIG.

  As described above, the user can focus on both the observation areas FA1 and FA2 only by selecting (clicking) the maximum focus position displays 66a and 66b displayed in association with the observation areas FA1 and FA2. it can. Therefore, the user can obtain a focus on a desired observation area among a plurality of observation areas in one operation, so that the efficiency of the observation work can be dramatically increased.

  Note that the number of observation regions that can be set is not limited to two, and an appropriate number that can be set may be determined according to the object, the image size, and the like.

  In the present embodiment, by moving the imaging unit 12 in the Z-axis direction, the subject distance from the imaging unit 12 to the target can be changed, and the cross-sectional height of the target focused by the imaging unit can be changed. However, the present invention is not limited to this configuration. As an example, it may be realized by a configuration including an imaging unit that can change a focal distance, such as a focus lens, and a driving device for changing the focal length of the imaging unit.

  In the present embodiment, the imaging drive unit 14 implements “focus height changing unit”, and the control unit 18 performs “focus value calculation unit”, “state value acquisition unit”, “focus value evaluation unit”, and “focus”. "Control means" is realized.

  According to the embodiment of the present invention, the imaging drive unit 14 changes the sectional height of the object focused by the imaging unit 12 and calculates the focus value F for the observation area FA. Then, among the calculated focus values F, the maximum focus value Fmax that maximizes the degree of focus is extracted, and the Z-axis position corresponding to the extracted maximum focus value Fmax is stored. Further, when a focus instruction is given, the imaging drive unit 14 is controlled so that the Z-axis position corresponding to the maximum focus value Fmax is obtained. For this reason, the degree of focus can be maximized for the observation area FA simply by giving a focus instruction.

  Thereby, the focus with respect to the observation area | region FA set in the image | photographed image can be obtained comparatively easily, and a user-friendly magnification observation apparatus is realizable.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is a schematic block diagram of the magnification observation apparatus according to embodiment of this invention. It is a figure which shows an example of the external appearance of the main-body part and display part according to this Embodiment. It is an example of the side view of the imaging mechanism according to this Embodiment. It is a figure which shows an example of the display in a display part. It is a figure for demonstrating the operation instruction | indication screen. It is a figure for demonstrating the operation | movement which concerns on operation of an operation instruction | indication lever. It is a figure for demonstrating the calculation principle of a focus value. An example of a change in focus value accompanying the movement of the imaging unit in the Z-axis direction is shown. It is a flowchart which shows the outline of the process according to this Embodiment. It is a figure for demonstrating the operation instruction | indication screen according to the modification 1 of this Embodiment. It is a figure which shows an example when two observation areas are set. It is a figure for demonstrating the example of a display of the operation instruction | indication screen according to the modification 2 of this Embodiment.

Explanation of symbols

  2 imaging mechanism, 4 body unit, 6 display unit, 8 input unit, 12 imaging unit, 14 imaging drive unit, 16 I / F unit, 18 control unit, 20 memory, 22 I / O control unit, 32 sample stage, 34 Stand, 36 Stand engaging member, 38 Imaging unit fixing member, 40 Operation instruction screen, 50 Operation instruction input area, 52 Operation instruction lever, 54u, 54d Operation instruction button, 60 State value display area, 62 Current position display, 64 Zero Position display, 66, 66a, 66b Maximum focus position display, 68 Reference point display, 70 Focus value display area, 72 Visualization display area, 74 Current position display, 76 Reference point display, 100 Magnification observation device, F Focus value, FA , FA1, FA2 Observation area, Fmax maximum focus value, PNT pointer, Pz Z-axis position, Pzmax maximum focus Kas position, T inflection point, VAL numerical value.

Claims (12)

An imaging unit for photographing an object;
A display unit for displaying an image captured by the imaging unit;
A focus height changing means capable of changing a cross-sectional height of the object focused by the imaging unit;
State value obtaining means for obtaining a state value corresponding to the cross-sectional height changed by the focus height changing means;
Focus value calculation means for calculating a focus value indicating a degree of focus by the imaging unit for an observation region set in an image captured by the imaging unit;
A focus value evaluation unit that extracts a maximum focus value at which the degree of focus is maximized from the focus values calculated by the focus value calculation unit, and stores the state value corresponding to the maximum focus value;
A magnification observation apparatus comprising: a focus control unit that controls the focus height changing unit so that the state value stored by the focus value evaluating unit is obtained in response to a focus instruction from the outside.   The magnification observation apparatus according to claim 1, wherein the focus height changing unit is controlled to operate according to an operation instruction from the outside.   The magnification observation apparatus according to claim 2, wherein the focus value evaluation unit extracts the maximum focus value within a range in which the focus height changing unit is actually operated according to the operation instruction.   The magnification observation apparatus according to claim 2, wherein the focus value evaluation unit determines an extreme value of the focus value that changes with the operation of the focus height changing unit as the maximum focus value.   The magnification observation apparatus according to claim 4, wherein the focus value evaluation unit determines an extreme value having the maximum absolute value among the plurality of extreme values as the maximum focus value.   The focus value evaluation unit causes the display unit to display a change characteristic of the focus value accompanying the operation of the focus height changing unit in association with the state value in the focus height changing unit. The magnification observation device according to any one of 5.   The magnification observation apparatus according to claim 6, wherein the focus value evaluation unit causes the display unit to display a change characteristic of the focus value together with the corresponding maximum focus value.   The focus value evaluation unit causes the display unit to display the current state value in the focus height changing unit and a state value corresponding to the maximum focus value. The magnified observation device described. The focus height changing means is configured to be able to give the operation instruction via an operation instruction screen displayed on the display unit,
The operation instruction screen is configured to be able to input the operation instruction in association with a relative relationship between the current state value displayed by the focus value evaluation unit and a state value corresponding to the maximum focus value. The magnification observation apparatus according to claim 8.   The magnification observation apparatus according to claim 9, wherein the operation instruction screen is configured to be able to input the focus instruction in association with a display area of a state value corresponding to the maximum focus value.   The magnification observation device according to claim 1, wherein the observation region is configured to be changeable according to a region setting instruction from the outside. The focus value calculation means calculates the focus value for each of the plurality of observation regions,
The focus value evaluation unit extracts the maximum focus value in the corresponding observation region based on each of the focus values calculated by the focus value calculation unit. The magnified observation device described.