Patent Description:
In order to find a suitable region of interest (ROI) of a sample, a user of a microscope has to shift a field of view (FOV) imaged by an optical system of the microscope relative to the sample. For this purpose, the microscope usually comprises a stage which can be moved in lateral x and y directions for shifting the observed FOV relative to the sample which is placed on the microscope stage. For moving the microscope stage in x and y directions, an actuator such as a stepping motor is controlled via an operating device which is operated by the user to cause the intended stage movement.

For example, the operating device may be formed by a remote control which is manually operated by the user. While manipulating the operating device, the user simultaneously observes an image of the FOV for instance by looking at a screen of a display device. The FOV shift caused by the user operation translates into a shift of a given sample portion, e.g. an ROI which is observed on the screen. An amount by which the observed ROI moves on the screen due to an FOV shift is determined by a response characteristic of the operating device manipulated by the user. Specifically, the response characteristic of the operating device defines a shift sensitivity according to which the FOV is moved relative to the sample when the user is manipulating the operating device. For example, in a coarse setting mode the response characteristic of the operating device provides a low shift sensitivity, and the FOV is moved by a large distance relative to the sample in response to a predetermined manipulation increment which the user applies to the operating device. In contrast, in a fine setting mode the response characteristic of the operating device provides a high shift sensitivity, and the FOV is moved by a small distance relative to the sample in response to the same manipulation increment.

Apparently, there is a proportional correspondence between the FOV shift on the sample and the ROI shift observed on the screen when the user is manipulating the operating device. Specifically, the FOV shift on the sample translates into an ROI shift on the screen, an amount of the ROI shift being determined by a total visual magnification based on which the FOV is converted into an image which can be observed by the user on the screen. The total visual magnification depends on several magnification factors of the microscope system. More specifically, these magnification factors multiply from the sample along an optical detection path up to the screen of the display device to a value that gives the total visual magnification. The magnification factors may be caused by optical and digital/virtual magnification components, and these components may provide for variable magnifications. For instance, an optical zoom system can be used to enlarge or reduce the size of the FOV which is to be imaged by the microscope. Further, a digital zoom for cropping and enlarging an image captured by a digital camera can be applied. All these variable magnification factors contribute to the total visual magnification based on which the FOV is visualized to the user.

Conventional microscope systems often ignore the fact that the total magnification based on which the sample is visualized to the user can become very large. This applies in particular if a digital or virtual zoom is applied. Therefore, in case of a rapid response characteristic of the operating device, i.e. a low shift sensitivity, x and y movements of the microscope stage may be too coarse to enable the user to visually follow a strongly zoomed ROI on the screen. In other words, there is a risk that an ROI may unexpectedly disappear from the user's view while the user is manipulating the operating device. As a result, handling of the microscope becomes difficult.

Document <CIT> discloses a microscope according to the preamble of claim <NUM>. This microscope comprises an optical observation system having objective lenses that collect transmitted light from the specimen irradiated with illumination light. The microscope system further comprises an image acquisition unit that captures the transmitted light collected by the objective lenses. The image acquisition unit is disposed so that it can be switched to other image acquisition devices having different maximum image-acquisition areas that can be captured. An input unit comprises a viewing-range setting unit that is connected to a mouse and is configured so that an area specified by the user can be set as the viewing range of the image by using the mouse on an image displayed on a monitor. Furthermore, a controller is provided to calculate a vertical scale factor and a horizontal scale factor of the viewing range of an image displayed on the monitor relative to the maximum image-acquisition area that can be captured by the image acquisition unit. The controller is further configured to calculate the moving speed of an electrically powered stage on which the specimen is arranged. A change of the viewing range takes place without changing the size of an observation image of the specimen.

Document <CIT> discloses a microscope having a stage that is driven by an electric motor. Motor control means are provided for controlling the motor such that the speed of a sample image is constant irrespective of the magnification of an objective lens.

Document <CIT> discloses a microscope comprising a stage on which a sample is movable, a stage drive unit for moving the stage, and an objective lens that is disposed to face the stage. Furthermore, a magnification detection unit is provided for detecting the magnification of the objective lens. The microscope is configured to calculate a movement amount and a movement direction for the stage drive unit to move the stage based on a partial region that is set for partially displaying image data obtained by an imaging device.

Document <CIT> discloses a microscope including a camera system and an objective with variable focal length. The microscope is configured to determine a speed of movement of a stage on which an object is located. Depending on a current magnification level, the translation speed of the objective may be relatively faster or slower.

Further reference is made to document <CIT> disclosing an optical scanning microscope.

It is an object of the present invention to provide a microscope comprising a control device and a method for controlling a microscope which enable a user to adjust a microscopic field of view to be imaged more easily and faster.

The afore-mentioned object is achieved by the subject-matter of the independent claims. Advantageous embodiments are defined in the dependent claims and the following description.

A control device for a microscope comprises an actuator configured to shift a microscopic field of view relative to a sample, an operating device configured to be operated by a user to control the actuator in accordance with a response characteristic determining a shift sensitivity according to which the field of view is shifted relative to the sample in response to a user operation of the operating device, and a processor configured to determine a total visual magnification based on which the field of view is visualized by the microscope to the user and to control the response characteristic of the operating device based on the total visual magnification.

Hereinafter, the terms magnification and zoom are to be understood in a broad sense, and these terms are used interchangeably. In any case, the term zoom refers to a magnification which can be varied, be it optically or digitally. Thus, in the field of optics, one might understand magnification and zoom in a narrow sense as referring to a system which includes optical elements, these elements being characterized by their optical parameters such as refractive powers, focal lengths, etc. Based on such an understanding, magnification and zoom would be defined by the optical parameters of the systems. However, while the present disclosure certainly covers such optical systems, it is by no means restricted thereto. In particular, the disclosure shall also cover magnification and zoom functionalities which are commonly referred to as digital or virtual magnification/zoom. For instance, in contrast to an optical zoom, a digital or virtual zoom may relate to means for cropping and enlarging an image captured by a digital camera in order to emulate the effect of a smaller or larger focal length of an optical zoom lens. The same effect can be achieved by using digital image processing to crop the digital image for enlarging the cropped image area which is displayed on a screen of a display device.

The control device enables a response characteristic of the operating device to be automatically adapted to a current total visual magnification based on which the image of the field of view (FOV) is visualized to the user. Thus, it is easier for the user to visually follow an imaged sample region of interest (ROI) when the user manipulates the operating device for shifting the FOV across the sample.

In conventional microscopes, a user manipulation of the operating device translates into a FOV shift on the sample in accordance with a constant conversion factor. In other words, the conversion factor remains the same regardless of whether the total visual magnification is high or low. If the total visual magnification is high, the ROI shift on the screen caused by a user manipulation may be too large to enable the user to visually follow the imaged ROI on the screen. On the other hand, if the total visual magnification is low, the ROI shift may be too small to render a visual ROI search efficient. In contrast, the control device disclosed herein allows to apply a conversion factor which is automatically adapted to the total visual magnification which is currently used for imaging the sample. Thus, a zoom scaled FOV shift is achieved which allows highly efficient ROI search on the screen.

It is to be noted that the control device allows an automatic adaption of the response characteristic of the operating device to the current total visual magnification while the microscope is operating. Thus, observing the image on the screen is very convenient and intuitive, and the user is free to concentrate exclusively on a specific task without being distracted by visual disturbances.

The control device is applied to a microscope comprising a confocal detection system. The control device may be applied to a combination of a microscope comprising a confocal detection system and a widefield microscope. In an embodiment not covered by the subject-matter of the claims the control device can be applied to a widefield microscope.

Preferably, the total visual magnification represents a relationship between a size of an image displayed on a display device of the microscope and a size of the field of view. While in the past microscopes usually used eyepieces for observing a sample, nowadays digital display devices such as monitors are widely used for image observation. Such display devices often provide digital zoom functions which may influence the total visual magnification to a large extent. The control device allows to compensate for adverse effects caused by a highly variable digital zoom when visualizing the sample during an FOV movement relative to the sample.

The processor is reconfigured to obtain an optical magnification and to determine the total visual magnification based thereon.

The processor may be configured to obtain a digital magnification and to determine the total visual magnification based thereon. Any combination of optical magnification and digital magnification can be dealt with efficiently to facilitate the handling of the microscope during an ROI search.

The processor may further be configured to obtain the optical magnification in accordance with a variable focal length of an optical zoom system of the microscope. If a zoom factor is large, it is especially beneficial to automatically adapt the response characteristic and thus the shift sensitivity with which the FOV is moved relative to the sample.

Preferably, the processor is configured to obtain the optical magnification in accordance with a focal length of an objective of the microscope, said objective being part of an objective changing system comprising a plurality of objectives with different focal lengths. In such a case, a set of objectives usually cover a wide range of available focal lengths so that the total visual magnification varies to a large extent depending on which objective is currently used. Therefore, it is a significant advantage to automatically adapt the response characteristic of the operating device to the total visual magnification.

The processor may be configured to obtain the optical magnification in accordance with a magnification of an optical camera mount system of the microscope. Such a mount system is utilized to couple a camera to the microscope. Taking into account the magnification of the mount system allows to compensate for significant changes in the total visual magnification that would otherwise make an observation during the FOV shift difficult.

The processor is configured to obtain the optical magnification in accordance with a variable scanning parameter of a confocal detection system of the microscope. The scanning parameter defines the size of the field of view which is scanned by the confocal detection system. Thus, it is possible to take into account a confocal zoom which may be implemented by suitably controlling a scanner included in the confocal detection system.

The processor may be configured to control the response characteristic such that the shift sensitivity varies monotonically depending on the total visual magnification. Preferably, the response characteristic varies linearly with the total visual magnification without being limited thereto. Thus, the processor may also be configured to control the response characteristic such that the shift sensitivity varies non-linearly as a function of the total visual magnification, for example exponentially. if e.g. the total visual magnification becomes very high during operation of the microscope, an exponential decrease of the response characteristic allows to reduce the FOV shift drastically so that the user is still enabled to visually follow an ROI on the screen.

Preferably, the actuator is configured to move a microscope stage holding the sample relative to an optical imaging system of the microscope to shift the field of view relative to the sample. Alternatively, the actuator may move an optical imaging system of the microscope relative to the stage.

The actuator may be configured to move the microscope stage perpendicular to an optical axis of the optical imaging system.

According to another aspect, a method for controlling a microscope according to appended claim <NUM> is provided.

<FIG> shows a diagram of a microscope <NUM> according to an embodiment. According to the embodiment shown in <FIG>, the microscope <NUM> is configured to combine widefield and confocal imaging. However, a configuration as shown in <FIG> is to be understood merely an example. Any other suitable type of microscope can be used, in combination with a confocal detection system, to provide a microscope control as explained hereinafter.

The microscope <NUM> provides two operating modes which can be selectively activated to perform either widefield imaging or confocal imaging. For the sake of simplicity, <FIG> is purely schematic and illustrates components of the microscope <NUM> in a relatively abstract manner that allows an operating principle to be explained in the present context. In particular, <FIG> does not detail specific configurations e.g. in terms of illumination and detection means which may be used to implement combined widefield and confocal imaging.

The microscope <NUM> comprises a control device generally referred to as <NUM> in <FIG>. The control device <NUM> comprises a processor <NUM>, an operating device <NUM>, and an actuator <NUM>. The operating device <NUM> may be formed by a remote control which is manually operated by a user as described hereinafter. The actuator <NUM> is coupled to the operating device <NUM> and may comprise e.g. a motorized driving unit such as a stepping motor coupled to drive axes etc. without being limited thereto.

The microscope <NUM> may further comprise a microscope stage <NUM> on which a sample <NUM> is located. The microscope stage <NUM> is movable in lateral x and y directions which define a plane parallel to a stage surface on which the sample <NUM> is held.

The microscope <NUM> may further comprise an optical imaging system <NUM> which serves both for widefield and confocal imaging of the sample <NUM>. An optical axis O of the optical imaging system <NUM> is perpendicular to the x and y directions along which the microscope stage <NUM> is movable by means of the actuator <NUM>. According to the present embodiment, the optical imaging system <NUM> includes an objective <NUM> facing the sample <NUM>. The objective <NUM> forms a detection lens for shared use in both operating modes, i.e. widefield and confocal imaging. In addition to the objective <NUM>, the optical imaging system <NUM> may comprise further optical components (not shown in <FIG>) for shared use in the widefield mode and the confocal mode. Further, the optical imaging system <NUM> may also include optical components which are exclusively used either in the widefield mode or in the confocal mode. This is illustrated in <FIG> by two spatially separated optical paths <NUM> and <NUM>, one of which being assigned to widefield imaging and the other being assigned to confocal imaging. Accordingly, the optical path <NUM> represents a widefield detection system, and the optical path <NUM> represents a confocal detection system. For simplicity, the widefield detection system and the confocal detection system are represented hereinafter by the optical paths <NUM> and <NUM>, respectively.

Among the optical components which are included in the widefield detection system <NUM>, an optical camera mount system <NUM> may be provided. Further, the widefield detection system <NUM> includes a 2D image sensor whereas the confocal detection system <NUM> comprises a confocal point sensor. Typically, the afore-mentioned sensors are spatially separated sensor units which are located at different positions within the optical imaging system <NUM>. However, it may also be envisaged to use a single sensor unit both for widefield and confocal detection. For instance, a widefield camera may also be used for confocal detection. Just for simplicity, <FIG> shows a single sensor unit <NUM> which can be understood as being formed either by one sensor or by two sensors.

The confocal detection system <NUM> may further comprise a scanner which is shown schematically as element <NUM> in <FIG>. The scanner <NUM> is used to scan illumination light along the x and/or y direction across the sample <NUM>. As principally known in confocal microscopy, the scanner <NUM> also serves to descan the detection light emerging from the sample <NUM> so that the detection light, although caused by a spatial scan across the sample <NUM>, can be received by a stationary point sensor if desired.

The microscope <NUM> shown in <FIG> comprises a display device <NUM> having a screen <NUM>. The display device <NUM> is configured to display an image of the sample <NUM> on its screen <NUM>. The image displayed on the screen <NUM> corresponds to a field of view (FOV) from which detection light is collected from the sample <NUM> through the objective <NUM> of the optical imaging system <NUM>.

The imaged FOV displayed on the screen <NUM> can be shifted by the user relative to the sample <NUM> by means of the operating device <NUM>. For this purpose, the user manipulates the operating device <NUM>, and the operating device <NUM> outputs a control signal corresponding to the user manipulation to the actuator <NUM>. Just as an example, the operating device may be formed by a manipulation unit of a joystick type which is connected to the processor <NUM> and the actuator <NUM>. In such a case, the user may swivel a manipulation stick of the operating device <NUM>, and a corresponding control signal is output to the actuator <NUM>. Thus, the actuator <NUM> moves the microscope stage <NUM> in the x-y plane in response to a user manipulation of the operating device <NUM> so that the FOV which is imaged by the optical imaging system <NUM> is correspondingly shifted relative to the microscope stage <NUM>. As a result, the FOV is laterally moved relative to the sample <NUM> which is stationary with respect to the microscope stage <NUM>. It is to be noted that any other type of operating device, which enables the user to shift the FOV relative to the sample <NUM>, may be used.

An amount by which the FOV is moved relative to the sample <NUM> depends on a response characteristic according to which the operating device <NUM> responds to a user manipulation. The response characteristic determines a distance by which the microscope stage <NUM> is moved in x and/or y by means of the actuator <NUM> when the user manipulates the operating device <NUM> with a given increment. For instance, if the user manipulates the operating device <NUM> with a predetermined unit increment A which translates into a unit motion of the microscope stage <NUM> by distance B, the response characteristic can be defined by a conversion factor B/A. Thus, an arbitrary manipulation of the operating device <NUM> in the amount C translates into a stage motion distance that equals C times the conversion factor B/A.

In case that the conversion factor is large, the operating device <NUM> has a rapid response characteristic, i.e. a low shift sensitivity, and a predetermined user manipulation of the operating device <NUM> causes an FOV shift on the sample <NUM> by a relatively large distance. In contrast, if the conversion factor is small, the operating device <NUM> has a slow response characteristic, i.e. a high shift sensitivity, and the user manipulation of the operating device <NUM> causes an FOV shift on the sample <NUM> by relatively small distance.

An FOV shift relative to the sample <NUM> that is caused by manipulating the operating device <NUM> translates into a shift of a given sample region, for example a region of interest (ROI) which is imaged by the optical imaging system <NUM> and observed by the user on the screen <NUM> of the display device <NUM>. As mentioned above, an amount of the FOV shift on the sample <NUM> depends on the response characteristic of the operating device <NUM>. Accordingly, an amount of the ROI shift on the screen <NUM> depends on the response characteristic of the operating device <NUM> likewise, and the distance by which the ROI is moving on the screen <NUM> corresponds with the distance by which the FOV moves relative the to the sample.

The proportionality between the FOV shift on the sample <NUM> and the ROI shift on the screen <NUM> is determined by a total visual magnification based on which the FOV is converted by the optical imaging system <NUM> into the image which is displayed on the screen <NUM> and observed by the user while manipulating the operating device <NUM>. The total visual magnification represents a relationship between the size of the image which is displayed on the screen <NUM> and the size of the FOV on the sample <NUM>. The total visual magnification may depend on a plurality of magnification factors which become effective in the microscope <NUM> when imaging the sample <NUM>. These magnification factors may be at least partially different depending on whether the widefield mode or the confocal mode is selected.

In the widefield mode three magnification factors may multiply to the total visual magnification along the optical detection path from the sample <NUM> up to the screen <NUM> where the image is finally observed by the user. Firstly, the objective <NUM> (possibly in combination with additional optical elements of the widefield detection system <NUM> which are not shown in <FIG>) may form an optical zoom system. A focal length of the optical zoom system can be varied between a minimum value and a maximum value. A current focal length which is set between minimum and maximum defines a (variable) first magnification factor. Secondly, the widefield detection system <NUM> may comprise the afore-mentioned camera mount system <NUM> which may provide a predetermined magnification, e.g. <NUM>. 6X defining a (fixed) second magnification factor. Thirdly, a digital or virtual zoom may be provided. For instance, if the image sensor <NUM> is formed by a digital 2D camera, only a part of an active image sensor area of the camera may be used for providing image data based on which the image is displayed on the screen <NUM> of the display device <NUM>. Additionally or alternatively, a digital zoom can also be achieved by post-processing of the image data which is output from the image sensor <NUM> to the display device <NUM>. In any case, the digital zoom defines a (variable) third magnification factor.

According to this example, the afore-mentioned first, second, and third magnification factors multiply to the total visual magnification in the widefield mode. Since some of the magnification factors may depend on the current zoom setting of the associated optical and/or digital zoom components, the total visual magnification varies with the current zoom setting. Accordingly, the proportionality between the FOV shift on the sample <NUM> and the ROI shift on the screen <NUM> varies in accordance with the variable total visual magnification in the widefield mode.

Correspondingly, in the confocal mode, three magnification factors may multiply to the total visual magnification along the optical detection path from the sample <NUM> up to the screen <NUM> where the image is finally observed by the user. Firstly, the objective <NUM> (possibly in combination with additional optical elements of the confocal detection system <NUM> which are not shown in <FIG>) may form an optical zoom system. Again, a focal length of the optical zoom system can be varied between minimum and maximum, and a current focal length set between minimum and maximum defines a (variable) first magnification factor. Secondly, the confocal mode may provide a so-called confocal zoom that is implemented by means of the scanner <NUM> included in the confocal detection system <NUM>. As mentioned above, the scanner <NUM> is used to move the illumination light across the sample <NUM>. At the same time, the scanner <NUM> is configured to descan the detection light emerging from the sample <NUM>. Accordingly, the size of the FOV on the sample <NUM> is determined by a scan area on the sample <NUM> which is covered by the scanner <NUM> wherein the number of pixels per captured FOV remains the same. Thus, a scanning parameter based on which the scanner <NUM> is controlled determines a (variable) second magnification factor. Thirdly, a digital or virtual zoom may be provided, for example by post-processing the image data which is output from the image sensor <NUM> to the display device <NUM> in the confocal mode. The digital zoom defines a (variable) third magnification factor.

Thus, the first, second, and third magnification factors multiply to the total visual magnification in the confocal mode. Some of the magnification factors may depend on the current zoom setting of the associated optical and/or digital zoom components so that the total visual magnification varies with the current zoom setting. As a result, the proportionality between the FOV shift on the sample <NUM> and the ROI shift on the screen <NUM> varies also in the confocal mode in accordance with the variable total visual magnification.

It is to be emphasized that the afore-mentioned magnification factors are merely examples. Any type of magnification and zoom configuration which takes influence on the total visual magnification on the screen <NUM> or on any other visualization means such as an eyepiece can be suitably considered. For instance, the objective <NUM> may be part of an objective changing system (schematically shown as block <NUM> in <FIG>) comprising a plurality of lenses with different focal lengths. By interchanging the lenses, the respective magnification factor changes correspondingly.

Hereinafter, an operating principle of the control device <NUM> is explained by way of the example shown in <FIG>. Thereby, reference is made to a flow diagram in <FIG> illustrating a method for controlling the microscope <NUM>.

In step S2, the processor <NUM> of the control device <NUM> determines an operating mode of the microscope <NUM>. In particular, it is determined whether the widefield mode or the confocal mode is selected.

In step S4, the processor obtains information on the current zoom/magnification setting of the microscope <NUM> in the respective operating mode. In particular, the processor <NUM> obtains several magnification factors as explained above. In case of variable magnifications, the magnification factors may be related both to optical and digital/virtual zoom components. Also fixed magnifications may be taken into account, for instance in case that the microscope <NUM> uses the objective changing system <NUM> which comprises a plurality of objectives having fixed focal lengths. The information on the respective magnification factors may be stored in advance in a memory of the control device <NUM> (in particular in case of fixed magnifications), and/or the information may be read out from the respective magnifying component during operation (in particular in case of variable magnifications).

In step S6, the processor <NUM> uses the magnification factors obtained in S4 to calculate the total visual magnification based on which the FOV is displayed on the screen <NUM> of the display device <NUM>. In the present example, the processor <NUM> multiplies three magnification factors provided in the respective operating mode, and the result of multiplication is the total visual magnification.

In step S8, the processor <NUM> obtains a total default magnification which may be a product of several predetermined default magnification factors. For example, these default magnification factors may comprise all fixed magnifications, i.e. all magnifications which are not changed by zooming. With regard to magnifications which are varied by zoom operations, specific default values within the respective zoom range may be taken into account when determining the total default magnification. Further, not all magnifications which take influence on the total visual magnification must be taken into account to calculate the total default magnification at this stage. For example, in the confocal mode the confocal zoom implemented by the scanner <NUM> may be disregarded when determining the total default magnification. Subsequently, the processor <NUM> determines a scale factor S by calculating the ratio of the default magnification and the total visual magnification obtained in S6.

In step S10, the processor <NUM> multiplies the original conversion factor B/A with the scale factor S so that a scaled conversion factor is obtained. The scaled conversion factor may be stored in a memory of the operating device <NUM>. From this point on, the actuator <NUM> is controlled in response to a user manipulation of the operating device <NUM> in accordance with a control signal which takes into account the scaled conversion factor rather than the initial conversion factor. In other words, the response characteristic of the operating device <NUM> is changed according to the scaled conversion factor.

If the total default magnification is larger than the total visual magnification, the scale factor S is larger than <NUM>, and the scaled conversion factor is larger than the original conversion factor. In this case, the response characteristic of the operating device <NUM> becomes faster, and a predetermined user manipulation of the operating device <NUM> causes a larger FOV shift on the sample <NUM>. Thus, the ROI shift that the user observes on the screen <NUM> when manipulating the operating device <NUM> becomes larger likewise.

Correspondingly, if the total default magnification is smaller than the total visual magnification, the scale factor S is smaller than <NUM>, and the scaled conversion factor is smaller than the original conversion factor. Therefore, the response characteristic of the operating device <NUM> becomes slower, and a predetermined user manipulation of the operating device <NUM> causes a smaller FOV shift on the sample <NUM>. Thus, the ROI shift that the user observes on the screen <NUM> when manipulating the operating device <NUM> becomes smaller.

As a result, the response characteristic of the operating device <NUM> can be automatically adapted to the current total visual magnification so that it is easier for the user to observe the image on the screen <NUM> while manipulating the operating device <NUM>.

According to the embodiment described above, the scale factor S is calculated such that the response characteristic varies linearly with the total visual magnification. However, this is merely an example. The scale factor can also be determined so that the response characteristic of the operating device <NUM> is varied non-linearly, e.g. exponentially with the total visual magnification.

Claim 1:
A microscope (<NUM>) comprising a control device (<NUM>) and a confocal detection system (<NUM>), wherein the control device (<NUM>) comprises:
an actuator (<NUM>) configured to shift a microscopic field of view relative to a sample (<NUM>),
an operating device (<NUM>) configured to be operated by a user to control the actuator (<NUM>) in accordance with a response characteristic determining a shift sensitivity according to which the field of view is shifted relative to the sample (<NUM>) in response to a user operation of the operating device (<NUM>),
a display device (<NUM>), and
a processor (<NUM>),
characterized in that the processor (<NUM>) is configured to determine a total visual magnification based on which the field of view is visualized by the microscope (<NUM>) on the display device (<NUM>) to the user and to control the response characteristic of the operating device (<NUM>) based on the total visual magnification,
that the processor (<NUM>) is configured to obtain an optical magnification and to determine the total visual magnification based thereon, and
that the processor (<NUM>) is configured to obtain the optical magnification in accordance with a variable scanning parameter of the confocal detection system (<NUM>), said scanning parameter defining the size of the field of view which is scanned by the confocal detection system (<NUM>).