Optical positioning aid for distance sensor, distance measurement system and corresponding method

Abstract

An optical positioning aid for a distance sensor (2) is disclosed to assist in positioning the distance sensor (2, 16) relative to a measurement object (8). The optical positioning aid (6) comprises a light source (10) and a control unit (14). The light source (10) is configured to generate an adjustment light beam (11), wherein the adjustment light beam (11) has a wavelength (λ) in the visible range and is suitable for generating a light spot on the measurement object (8). The control unit (14) has a distance input (15) and is communicatively connected to the light source (10) for controlling at least one characteristic of the adjustment light beam (11). The control unit (14) is configured to evaluate an input value input into the distance input (15) and to influence at least one characteristic of the adjustment light beam (11) based on the evaluation result, so that the adjustment light beam (11) allows conclusions about the input value. In addition, a distance measuring system (1, 1') having the optical positioning aid (6) and a method for assisting in positioning a distance sensor (2, 16) relative to a measurement object (8) are disclosed.

Description

Technical Field

[0001] The present invention relates to an optical positioning aid for a distance sensor to assist the positioning of the distance sensor relative to a measurement object. The present invention also relates to a distance measurement system and a corresponding method. Background Art

[0002] Distance sensors are of particular importance in many technical fields. Distance sensors are used to measure the distance between the sensor and the measured object. From the measured distance, not only information about the distance of the measured object from the sensor can be obtained, but also, depending on the evaluation performed, information about the contour of the measured object, the layer thickness, the gap width, the surface quality or even simply about whether the measured object is present, to name just a few typical examples. The known sensor technologies and the possibilities for evaluating the sensor signals are correspondingly diverse. Depending on the field of application and the measured object to be measured, optical sensors (e.g. interferometric, confocal colorimetric or triangulation sensors), capacitive or inductive sensors are used.

[0003] The distance sensor has a distance measuring range and a transverse measuring range. The distance measuring range indicates from which distance (minimum measuring distance) to which distance (maximum measuring distance) between the measuring object and the distance sensor can be measured. The minimum measuring distance can always reach the distance sensor. However, in practice, the minimum measuring distance is usually spaced apart from the distance sensor. The transverse measuring range indicates in which range transverse to the distance measuring range the measuring object can be measured.

[0004] For some sensor technologies, it is relatively easy to identify the distance measurement range and / or the lateral measurement range. Thus, for example, triangulation sensors use light in the visible range, which makes it easy to laterally position the measurement object. However, even in this case, the distance measurement range can usually only be guessed. For sensors that measure outside the visible range (e.g. with measuring light in the infrared range) or capacitive or inductive sensors, the measurement object can only be correctly positioned using a data sheet and a ruler (or other comparative measuring device).

[0005] Since it is not uncommon to have to precisely position distance sensors when installing them in a machine or facility, such installation often results in a complex and error-prone activity. The problem is even further exacerbated if the distance measuring range and / or the lateral measuring range are small, e.g. the distance measuring range only extends for a few millimeters and the lateral measuring range is less than one millimeter wide. In such cases, positioning without additional aids is practically impossible.

[0006] Therefore, in practice, measuring systems are known that have positioning aids to assist the setter in positioning the distance sensor relative to the measured object. In addition, the controller unit of the measuring system has a display that enables the measured distance values ​​to be classified. When the measured distance value is in the center of the measuring range, the display can, for example, be displayed by a green LED (light emitting diode). In this way, the setter can relatively accurately position the distance sensor and the measured object relative to each other. The disadvantage of this is that the setter must constantly switch his line of sight back and forth between the distance sensor and the controller unit. Only after viewing the display of the controller unit can the adaptation performed on the distance sensor be verified. This can make the setting process very complicated and time-consuming. Summary of the invention

[0007] The object of the present invention is to design and develop a positioning aid, a distance measuring system and a method of the type mentioned in the introduction such that a positioning of the distance sensor relative to the measurement object is as simple as possible.

[0008] According to the invention, the above-mentioned object is achieved by the features of claim 1. Accordingly, the positioning aid in question comprises:

[0009] a light source for generating a modulated light beam, wherein the modulated light beam has a wavelength in the visible range and is suitable for generating a light spot on the measurement object, and

[0010] a control unit having a distance input and being communicatively connected to the light source for controlling at least one property of the adjusted light beam,

[0011] The control unit is designed to evaluate an input value entered into the distance input and to influence at least one property of the adjustment light beam based on an evaluation result, such that the adjustment light beam allows a conclusion to be drawn from the input value.

[0012] With regard to the distance measuring system, the above-mentioned object is achieved by the features of claim 6. According to this, the distance measuring system in question comprises:

[0013] a distance sensor for measuring the distance between the distance sensor and a measurement object, and

[0014] According to the optical positioning aid device of the present invention,

[0015] The distance sensor is communicatively connected to the positioning aid and inputs an input value representing a measured distance value into a distance input of the positioning aid.

[0016] With regard to the method, the above-mentioned object is achieved by the features of claim 12. According to this, the method in question comprises the following steps:

[0017] generating an input value by measuring the distance between the measurement object and the distance sensor,

[0018] evaluating the input value to produce an evaluation result,

[0019] generating a regulated light beam by means of a light source of the positioning aid, and

[0020] deflecting the adjusted light beam onto the measurement object to generate a light spot on the measurement object,

[0021] Therein, at least one property of the conditioned light beam is influenced based on the evaluation result, such that the conditioned light beam allows conclusions to be drawn about the input value.

[0022] In the manner according to the invention, it is firstly recognized that the distance sensor can be simply positioned in such a way that information about the measured distance value can be directly recognized on the measured object. For this purpose, a control beam is used according to the invention, which is designed to generate a visible light spot when it is incident on the measured object. For this purpose, the control beam has at least one wavelength in the visible range, i.e. a wavelength between 380 nm and 750 nm. In addition, at least one characteristic of the control beam can be influenced based on the input distance value, so that the input distance value can be inferred by observing the light spot. This is done in such a way that the influence on at least one characteristic of the control beam is carried out in the visible range and thus has an influence on the light spot on the measured object that can be recognized by the naked eye.

[0023] In order to generate such an adjustment beam, a positioning aid is provided according to the present invention, which includes a light source and a control unit. The positioning aid can form a distance measurement system together with a distance sensor (and possible other modules). The light source generates the adjustment beam, which is deflected onto the measurement object and can generate a light spot there. This requirement is conditioned on the light source being constructed to generate a sufficiently focused beam. The control unit has a distance input, which can be connected to the distance sensor and input an input value into the distance input. The control unit is connected to the light source in a communication manner and is constructed to control at least one characteristic of the adjustment beam. The control unit evaluates the input value input into the distance input and generates an evaluation result during the evaluation. Based on the evaluation result, the control unit affects the light source so that one or more of the at least one characteristic of the adjustment beam allow for inferences about the input value. In this way, it is possible to read from the light spot on the measurement object how the input value corresponds to the evaluation criteria used when evaluating the input value.

[0024] The adjustment beam can be formed by a monochromatic beam, i.e. the adjustment beam has only a single wavelength or a narrow wavelength range (e.g. narrower than 10 nm or narrower than 5 nm). However, it is also conceivable that the adjustment beam is polychromatic, i.e. has a plurality of discrete wavelengths and / or one or more wavelength ranges. Such an adjustment beam can be used in conjunction with the present invention as long as at least one wavelength of the adjustment beam is in the visible range and the adjustment beam causes a change in the light spot on the measurement object that can be recognized by the naked eye when its characteristics change.

[0025] In principle, the positioning aid and therefore the light spot can be positioned on the measurement object in different ways. In particular, when the positioning aid is mounted as an external unit on the distance sensor, the light spot can be arranged at a distance from the lateral measuring range of the distance sensor. Such a position of the light spot can be used as long as it is ensured that the installer can identify the light spot during the positioning of the distance sensor without having to significantly change his line of sight. It is recommended that the movement of the distance sensor and therefore the deflection of the measuring range also leads to a deflection of the adjustment light beam, i.e. the movement of the distance sensor and the movement of the positioning aid are coupled. In a preferred design, the light spot is arranged in the lateral measuring range of the distance sensor. In most cases, this can mean that the light spot is located on the optical axis of the measuring light.

[0026] The control unit can also be constructed in different ways. The control unit can be realized by pure circuit technology, i.e. by interconnecting discrete components (e.g. resistors, capacitors, transistors) and, if necessary, using integrated circuits (e.g. logic gates or comparators). However, in one embodiment, the control unit is realized by a combination of hardware and software. For this purpose, the control unit has a microprocessor, a working memory, a program memory and corresponding interfaces, wherein a computer program is stored in the program memory, the execution of which enables the control unit to perform the corresponding tasks.

[0027] The control unit can be solely responsible for the positioning aid. However, it is also conceivable that the control unit is a component of other systems and / or superordinate systems. Thus, when a positioning aid is used in a measuring system, the control unit can perform the tasks of the positioning aid, for example, as well as the tasks of the distance sensor or other components of the measuring system.

[0028] In one design, at least one characteristic of the adjustment light beam can be formed by the wavelength of the adjustment light beam. This means that the control unit can act on the light source so that the color of the adjustment light beam changes in a recognizable manner depending on the input value. The adjustment light beam can thus be, for example, red when the input value entered into the distance input is outside the rated range, for example outside the distance measurement range or outside the center of the measurement range. If the input value can be inferred that the distance between the distance sensor and the measurement object is within the distance measurement range or close to the center of the measurement range, the adjustment light beam can be transformed into green, for example. It is also conceivable that the wavelength changes continuously or in multiple levels, for example in multiple levels from red to green. In this case, the control unit classifies the input values ​​into multiple areas and selects the color of the adjustment light beam according to the identified areas and controls the light source accordingly.

[0029] In another design, at least one characteristic of the adjustment light beam may include intensity. This means that the intensity of the adjustment light beam is changed depending on the input value and its evaluation. Thus, for example, the adjustment light beam can be controlled to different brightnesses so that it exhibits a maximum intensity when a rated value is reached.

[0030] In another design, at least one characteristic of the adjustment beam includes a variation pattern. This means that another characteristic of the adjustment beam changes in different patterns. For example, it is conceivable that the intensity of the adjustment beam changes depending on the evaluation of the input value. Thus, for input values ​​far from the rated value, the adjustment beam can have a low intensity, for example equal to 0, for most of the variation period. The closer the input value is to the rated value, the more likely the ratio between low intensity and high intensity will shift in the direction of high intensity. In this way, it is easy to identify the proximity of the input value to the rated value by the change in intensity. This can also be done for the wavelength, for example by switching between two or more wavelengths / wavelength ranges.

[0031] In another design, at least one characteristic of the adjustment beam includes a frequency of change of the adjustment beam. This means that another characteristic of the adjustment beam changes, and the frequency of the change is influenced by the input value. Thus, when the input value is far from the rated value or the rated range, the intensity of the adjustment beam can, for example, be switched between a low intensity and a high intensity at a low frequency, for example once per second or once every two seconds. The closer the input value is to the rated value or the rated range, the faster the switching between two intensity values ​​can be. Two or more change frequencies can be used here. In this way, it can be identified how far the input value is from the rated value. Correspondingly, the wavelength can be changed.

[0032] The above-mentioned designs for changing the characteristics of the adjustment beam can be combined in any way. Here, different characteristics can acquire different meanings. Thus, for example, when the input value is outside the measurement range, the adjustment beam can be red. Once the input value reaches the measurement range, it can be changed to green. The closer the input value is to the center of the measurement range, the more likely the ratio between low intensity and high intensity will shift in the direction of high intensity. For a person skilled in the art, the possibilities and combinability of various solutions will be conceivable.

[0033] In principle, the light source can be realized in different ways. It is important here that the light source is able to output a sufficiently focused light beam and can be controlled sufficiently well. However, these requirements can be met by various light generators, possibly in combination with downstream optical devices. Possible designs of the light source include light emitting diodes (LEDs) or laser diodes. In this case, the focusing device for influencing the beam path of the light beam can be arranged downstream of the actual light generator of the light source.

[0034] Furthermore, the light source may include further optical means. Such optical means may include, for example, color or polarization filters. In an extension, such optical means are configured to influence one or more properties of the adjustment light beam. Thus, such optical means may, for example, be used to change the intensity of the adjustment light beam.

[0035] The input value entered into the distance input of the control unit of the positioning aid can be formed differently and have different meanings. It is important that the input value has a relationship with the detected distance. How this relationship is specifically formed is secondary.

[0036] In one embodiment, the input value is formed by a distance value, which may be directly related to the distance between the measuring object and the distance sensor and may directly represent the distance measured by the distance sensor.

[0037] In another design, the input value is formed by an evaluation metric representing the measured distance. Thus, when the measured distance value is greater than the measuring range of the distance sensor, the evaluation metric can be greater than 1, for example. If the detected distance is within the measuring range, the evaluation metric can take a decimal value between 0 and 1. A linear mapping (or other clear relationship) between the distance value and the evaluation metric can be used here. Using a value less than or equal to 0 makes it possible to identify distances less than the minimum measured distance. In principle, other evaluation metrics representing the measured distance, such as logical values, can also be used.

[0038] In another embodiment, the input value can also be the difference of the distance value relative to a reference point in the distance measuring range of the distance sensor. The reference point can be, for example, the center of the measuring range, the starting point of the measuring range or the end point of the measuring range. The difference formed in this way can be present as an absolute value or can be normalized to the size of the measuring range.

[0039] The positioning aid according to the invention can be a component of the distance measuring system according to the invention. For this purpose, the distance measuring system according to the invention also includes a distance sensor in addition to the optical positioning aid for measuring the distance between the distance sensor and the measurement object. The distance sensor is connected to the positioning aid in a communicative manner and inputs input values ​​into the distance input of the positioning aid. For this purpose, the distance sensor can have a correspondingly designed unit, which generates input values ​​suitable for the positioning aid and outputs them to the positioning aid.

[0040] In the distance measuring system according to the invention, the positioning aid and the distance sensor can be formed by two separate units, which are preferably connected to each other (fixedly or releasably). The positioning aid can thus be fixed to the housing of the distance sensor. In a preferred design, however, the positioning aid and the distance sensor form one unit, which can usually be expressed by the positioning aid and the distance sensor being arranged in a common housing.

[0041] In principle, the adjustment beam can be arranged in any way relative to the measuring range of the distance sensor, as long as the adjustment beam generates a recognizable light spot on the measurement object. However, in a preferred design, the adjustment beam and the measuring range of the distance sensor are coupled. This means that in one design, the adjustment beam characterizes the measuring range of the distance sensor, in particular the lateral measuring range of the distance sensor.

[0042] In principle, the distance sensor of the distance measuring system according to the invention can be formed in various ways and can operate according to various sensor technologies. As long as the distance sensor can generate and output suitable input values ​​for the positioning aid, the distance sensor is in principle suitable for the distance measuring system according to the invention.

[0043] In one embodiment, the distance sensor is formed by an optical sensor. This means that the distance sensor sends measurement light and, based on the detection light formed by the reflection of the measurement light on the measurement object, infers the distance of the illuminated point on the surface of the measurement object. In this case, the optical sensor can be designed as an interferometric sensor, a confocal colorimetric sensor, a triangulation sensor or in another way. Such sensors are well known in practice.

[0044] In another embodiment, the distance sensor is formed by a capacitive sensor. Such a sensor measures the influence of a measurement object located in the sensor's measuring range on the sensor's capacitance. Such a sensor can also be combined with an optical positioning aid, since the adjustment light beam does not influence the measurement of the capacitive sensor.

[0045] In another embodiment, the distance sensor is formed by an inductive sensor. An inductive sensor detects the influence of the measuring object on the sensor inductance, for example by generating eddy currents in the measuring object or by changing the magnetic permeability in the sensor measuring range. An optical positioning aid can also be advantageously combined with such a sensor.

[0046] When an optical sensor is used, the distance measuring system can include an optical coupler, with which the measuring light beam and the adjustment light beam sent by the distance sensor are coupled. In this way, the measuring light beam and the adjustment light beam can be input-coupled into a common optical device, so that the common optical device can deflect both the measuring light beam and the adjustment light beam to the measurement object. Here, the common optical device is preferably formed by an optical waveguide. This design can be used particularly advantageously when the distance measuring system includes a passive measuring head, from which the measuring light is deflected onto the measurement object and the passive measuring head picks up the reflected light reflected on the measurement object again. Even if optical errors (such as chromatic aberrations) are allowed to occur due to different wavelengths of the adjustment light beam and the measuring light beam and due to the optimization of the measuring optical system for the measuring light beam, the measuring light beam and the measuring light beam can still achieve good coaxiality.

[0047] When using optical sensors that emit measuring light in the visible range, in one development the measuring beam can be used as an adjustment beam. In order to avoid negative influences on the measurement of the distance sensor, an adjustment mode can be set, during which one of the characteristics of the measuring / adjusting beam is changed. In this development, it may make sense to reduce the number of affected characteristics.

[0048] In a method according to the invention, which can be used to assist in the positioning of a distance sensor relative to a measurement object, preferably using a distance measuring system according to the invention, an input value is generated in a first step. The input value is generated by measuring the distance between the measurement object and the distance sensor. In a next step, the input value is evaluated and an evaluation result is obtained in the process. The evaluation result is used to influence at least one property of an adjustment light beam. In a next step, an adjustment light beam is generated using these properties with the aid of a light source of a positioning aid, and in a further step, the adjustment light beam is deflected onto the measurement object to generate a light spot on the measurement object. By influencing at least one property of the adjustment light beam based on the evaluation of the input value, the input value can be inferred from the adjustment light beam and the light spot generated by the adjustment light beam on the measurement object.

[0049] In an extension of the step of evaluating the input value, the input value is compared with a nominal value and / or a nominal range. By means of this comparison, it can be determined how close the input value is to the nominal value or the nominal range. It is understood that the input value and the nominal value / nominal range should be adapted to each other. This means in particular that the input value and the nominal value / nominal range are scaled identically.

[0050] In one development, the setpoint value and / or the setpoint range characterizes a distance measuring range of the distance sensor. In one embodiment, a control beam having a first set of characteristics is generated when the input value is within the distance measuring range, and a control beam having a second set of characteristics is generated when the input value is outside the distance measuring range. The first set of characteristics and the second set of characteristics are different. In this way, it is possible to directly recognize from the control beam whether the input value is within or outside the distance measuring range.

[0051] In another embodiment, an adjustment beam with a third set of characteristics is generated when the input value is within the characteristic range of the distance measuring range, and an adjustment beam with a fourth set of characteristics is generated when the input value is outside the characteristic range. Here, the third set of characteristics and the fourth set of characteristics are different from each other. The characteristic range of the distance measuring range is formed by the measuring range starting point in one embodiment, by the measuring range center in another embodiment, and by the measuring range end point in another embodiment. Although the measuring range starting point, the measuring range center and the measuring range end point are in principle specific distance values, it is proposed in conjunction with the present invention to expand these values ​​into ranges. This is because the distance sensor can rarely be positioned so accurately that the measuring range center, the measuring range starting point or the measuring range end point are specifically reached. Therefore, the characteristic range should be wide enough to enable the distance sensor to be positioned at these values ​​in practical applications. At the same time, the characteristic range should be narrow enough to be able to fully represent the corresponding distance value. Preferably, the characteristic range here deviates from the measuring range starting point, the measuring range center or the measuring range end point by no more than 10% of the entire distance measuring range, particularly preferably by no more than 5% of the entire distance measuring range, and very preferably by no more than 3% of the distance measuring range.

[0052] In principle, the above-described designs for comparing the input value with the nominal value / nominal range can also be combined with one another. It is conceivable that, for the case where the input value is outside the distance measurement range, a control beam with a second set of characteristics is generated, for the case where the input value is within the distance measurement range but outside the characteristic range, a control beam with a first set of characteristics is generated, and for the case where the input value is within the characteristic range of the distance measurement range, a control beam with a third set of characteristics is generated. In this way, very detailed information about the input value can be output to the setter by means of the control beam without having to display the specific input value. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] There are now various possibilities for designing and expanding the teaching of the present invention in an advantageous manner. For this purpose, reference is made on the one hand to the claims that are subordinate to the independent claims and on the other hand to the following explanation of preferred exemplary embodiments of the invention based on the drawings. In conjunction with the explanation of preferred exemplary embodiments of the invention based on the drawings, preferred designs and expansions of the teaching are also explained in general. In the drawings

[0054] Figure 1 shows a schematic diagram of a first embodiment of a distance measuring system according to the invention, the distance measuring system having a distance sensor in the form of an interferometric sensor,

[0055] Figure 2 A schematic diagram showing an embodiment of a positioning aid device according to the present invention is shown,

[0056] Figure 3 shows a schematic diagram of a second embodiment of a distance measuring system according to the invention having a distance sensor in the form of a triangulation sensor,

[0057] Figure 4 a graph showing an exemplary curve of variation of the pulse duration and / or duty cycle of an adjusted light beam,

[0058] Figure 5 shows a diagram with an exemplary profile of the intensity caused by a change in the pulse duty factor as a function of the measuring path x,

[0059] Figure 6 shows a diagram with an exemplary profile of the intensity as a function of the measuring path x, and

[0060] Figure 7 A graph with an exemplary curve of wavelength variation of a tuned light beam is shown. DETAILED DESCRIPTION

[0061] Figure 1A schematic diagram of a first embodiment of a distance measuring system according to the invention is shown. The distance measuring system 1 comprises a distance sensor 2 in the form of a white light interferometric measurement sensor, which generates polychromatic measuring light in the near infrared range (NIR). The measuring beam is guided to an optical coupler 3 by means of an optical waveguide, at the output of which an optical waveguide 4 is arranged. The optical waveguide 4 forwards the measuring beam to a measuring head 5. A second input of the optical coupler 3 is connected to a positioning aid 6, which generates an adjustment beam and outputs the adjustment beam to the measuring head 5 via the optical coupler 3 and the optical waveguide 4. The measuring head 5 emits an illumination beam 7 to a measuring object 8, wherein the illumination beam 7 is the sum of the measuring beam and the adjustment beam. Since the measuring beam and the adjustment beam use the same measuring optics, the two beams are arranged coaxially with each other. The illumination beam 7 is reflected on the surface of the measuring object 8. The spectral components of the illumination beam 7 focused on the surface of the measuring object 8 are returned to the distance sensor 2 via the measuring head 5, the optical waveguide 4 and the optical coupler 3. The distance a to the measuring object 8 is inferred from the received spectral components. The evaluation unit 9 serves to evaluate, store and display the measured values ​​for a user.

[0062] exist Figure 2 . The positioning aid 6 has a light source 10, which generates and outputs an adjustment light beam 11. The light source 10 itself comprises a light generator 12 and an optical device 13. The light generator 12 can be formed by an LED or a laser diode. The optical device 13 can include a focusing device or another optical device for influencing at least one optical property of the adjustment light beam 11. The positioning aid 6 also has a control unit 14, which is connected to the light source 10 in a communicative manner. The control unit 14 also has a distance input terminal, into which an input value representing the measured distance can be input.

[0063] When the distance measuring system 1 is in operation, the distance sensor 2 generates a distance measurement value by measuring the distance a to the measuring object 8. This distance measurement value is input into a distance input 15 of a control unit 14, possibly using an evaluation unit 9. The control unit 14 is designed to evaluate the input value inputted and to influence at least one property of the adjustment beam based on the evaluation result, so that the adjustment beam allows the input value to be inferred. By the coaxial arrangement of the measuring beam and the adjustment beam, the lateral measuring range of the distance sensor 2 can be inferred by the light spot generated by the adjustment beam on the surface of the measuring object 8. Even if the measuring beam is outside the visible range, by the adjustment beam 11 in the visible range and by influencing at least one property of the adjustment beam based on the input value, it is possible to infer the correct positioning of the distance measuring system 1 relative to the measuring object 8.

[0064] Figure 3A second embodiment of a distance measuring system 1 ′ according to the invention is schematically shown, in which the distance sensor is designed as a triangulation sensor 16. For the sake of clarity, only the light source for generating the measuring beam 17 is shown, without the detection unit of the sensor. In this embodiment, there is also a positioning aid 6, which generates an adjustment beam 11 and emits it in the direction of the measuring object 8. Since the illumination beam 11 and the measuring beam 17 form a triangle, the adjustment beam only roughly characterizes the lateral measuring range of the triangulation sensor 16. However, the measuring beam 17 of the triangulation sensor 16 is in the visible range, so that the lateral measuring range of the distance measuring system 1 ′ can be seen from the measuring beam 17. In this case, the adjustment beam 11 only serves to make the distance measuring range recognizable.

[0065] In an extension of this second embodiment, an optical coupler can be used, as in the first embodiment, which couples the measuring beam and the adjustment beam coaxially, for example. It is also conceivable that no separate positioning aid is used, but that the positioning aid is a component of the triangulation sensor, i.e. the measuring beam is used as the adjustment beam in the adjustment mode and its intensity is varied, for example, depending on the measured distance.

[0066] exist Figures 4 to 7 Four possibilities of how the characteristics of the adjustment beam can be changed are shown by way of example in FIG. Figure 4 In the example above, the intensity of the beam is adjusted over time at the upper intensity value I 0 and an intensity value equal to 0. In this case, the period length T of the variation and thus the variation frequency can be selected as a function of the measured distance value.

[0067] Figure 5 Another variation of the intensity according to the measurement path x is shown by changing the duty cycle t 1 / T. Here, t 1 Indicates that during this period, the intensity takes the upper limit intensity value I 0 The period length T can be kept constant. The measured distance deviates from the center of the measurement range X M The farther away, the strength takes the upper limit strength value I 0 At a duty cycle of 100%, the upper limit intensity value I is continuously used. 0 If the period length T is in the range of seconds, a modulated light beam is generated in this way which pulses less and less as it reaches the center of the measuring range. In the case of short period lengths, for example in the range of 10 milliseconds or less, the measuring path becomes more and more stable the closer it gets to the center of the measuring range X. M , the brighter the beam appears.

[0068] exist Figure 6 In the measurement range, the intensity I varies according to the measurement path x.M The maximum intensity I of the adjusted beam is reached in the area max The measured distance deviates from the center of the measurement range X M The further away, the more the intensity I decreases. In the example shown, the intensity has a bell-shaped dependence on the measured value.

[0069] Figure 7 A very similar dependence is shown in . However, here the wavelength λ of the light beam is adjusted according to the measurement path x at the following wavelength value λ 1 and the upper wavelength value λ 2 Here, at the center of the measurement range X M When the upper wavelength value λ is reached 2 .

[0070] With regard to further advantageous embodiments of the positioning aid according to the invention and of the distance measuring system according to the invention, reference is made to the general part of the description and to the appended claims to avoid repetitions.

[0071] Finally, it should be clearly pointed out that the above embodiments are only used to explain the teachings claimed for protection, but are not limited to these embodiments.

[0072] Reference numerals list

[0073] 1 Distance measurement system

[0074] 2 Distance Sensor

[0075] 3 Optical coupler

[0076] 4 Optical waveguide

[0077] 5 Measuring head

[0078] 6 Positioning aids

[0079] 7 illumination beam

[0080] 8 Measurement Objects

[0081] 9 Evaluation Units

[0082] 10 Light Source

[0083] 11 Adjust the beam

[0084] 12 Light Generator

[0085] 13 Optical Devices

[0086] 14 Control unit (of positioning aid)

[0087] 15 Distance input

[0088] 16 Triangulation Sensor

[0089] 17 Measuring beam

Claims

1. A distance measurement system, include: a distance sensor (2, 16) for measuring a distance (a) between the distance sensor (2, 16) and a measurement object (8); and An optical positioning aid (6) for a distance sensor (2), the optical positioning aid (6) being used to assist in positioning the distance sensor (2, 16) relative to a measurement object (8), comprising: A light source (10) for generating a modulated light beam (11), wherein the modulated light beam (11) has a wavelength (λ) in the visible range and is suitable for generating a light spot on a measurement object (8), and a control unit (14) having a distance input (15) and being communicatively connected to the light source (10) for controlling at least one characteristic of the adjusted light beam (11), wherein the control unit (14) is designed to evaluate an input value input into the distance input (15) and to influence at least one property of the adjustment light beam (11) based on the evaluation result, so that the adjustment light beam (11) allows conclusions to be drawn about the input value, The distance sensor (2, 16) is connected to the positioning aid (6) in a communication manner and inputs an input value representing the measured distance value into a distance input terminal (15) of the positioning aid (6). Wherein, the distance sensor (2, 16) is formed by an optical sensor, The invention is characterized in that an optical coupler (3) is provided, wherein the optical coupler (3) couples the measuring light beam and the adjusting light beam (11) sent by the distance sensor (2), so that the measuring light beam and the adjusting light beam (11) can be deflected to the measuring object (8) by means of a common optical device.

2. The distance measuring system according to claim 1, It is characterized in that At least one characteristic of the adjusted light beam (11) includes a wavelength (λ), an intensity (I), a variation pattern and / or a variation frequency of the adjusted light beam (11).

3. The distance measurement system according to claim 1, It is characterized in that The light source (10) comprises a light generator (12).

4. The distance measurement system according to claim 1, It is characterized in that The light source (10) comprises optical means, by means of which the at least one property of the adjusted light beam can be influenced.

5. The distance measurement system according to claim 1, It is characterized in that The input value is formed by a distance measurement value, an evaluation measure representing the measured distance or a difference of a distance measurement value relative to a reference point in a distance measuring range of the distance sensor.

6. The distance measurement system according to claim 1, It is characterized in that The adjustment light beam (11) is arranged relative to the distance sensor (2, 16) in such a way that the adjustment light beam (11) characterizes a lateral measuring range (2, 16) of the distance sensor (2, 16).

7. The distance measurement system according to claim 1, It is characterized in that The optical sensor is designed as an interferometric sensor (2), a confocal colorimetric sensor or a triangulation sensor (16).

8. The distance measuring system according to claim 7, It is characterized in that The common optical device is formed by an optical waveguide (4).

9. The distance measuring system according to claim 7 or 8, It is characterized in that The optical sensor sends a measuring light beam (17).

10. The distance measurement system according to claim 1, It is characterized in that The distance sensor is composed of a capacitive sensor or an inductive sensor.

11. The distance measuring system according to claim 3, It is characterized in that The light generator (12) is a light emitting diode or a laser diode.

12. The distance measuring system according to claim 3, It is characterized in that The light source (10) comprises a focusing device for influencing the optical path of the adjusted light beam.

13. The distance measuring system according to claim 9, It is characterized in that The measuring beam (17) can be used as an adjustment beam during an adjustment mode of the sensor.

14. A method for assisting the positioning of a distance sensor relative to a measurement object, using the distance measurement system according to claim 1, The following steps are involved: generating an input value by measuring the distance (a) between the measuring object (8) and the distance sensor (2, 16), evaluating the input value to produce an evaluation result, generating a regulated light beam (11) by means of a light source (10) of the positioning aid (6), and deflecting the adjustment light beam (11) onto the measurement object (8) to generate a light spot on the measurement object (8); At least one property of the adjustment light beam (11) is influenced based on the evaluation result, such that the adjustment light beam (11) allows conclusions to be drawn about the input value.

15. The method according to claim 14, It is characterized in that In the step of evaluating the input value, the input value is compared with a setpoint value and / or a setpoint range.

16. The method according to claim 15, It is characterized in that The rated value and / or the rated range characterizes a distance measuring range of the distance sensor (2, 16), wherein when an input value is within the distance measuring range, an adjustment light beam (11) having a first set of characteristics is generated, and when the input value is outside the distance measuring range, an adjustment light beam (11) having a second set of characteristics is generated, wherein the first set of characteristics and the second set of characteristics are different from each other.

17. The method according to claim 15 or 16, It is characterized in that The rated value and / or the rated range characterizes a distance measurement range of the distance sensor (2, 16), wherein when an input value is within a characteristic range of the distance measurement range, an adjustment light beam (11) having a third set of characteristics is generated, and when the input value is outside the characteristic range, an adjustment light beam (11) having a fourth set of characteristics is generated, wherein the third set of characteristics and the fourth set of characteristics are different from each other.

18. The method according to claim 17, It is characterized in that When the input value is at the start point of the measuring range, the center of the measuring range or the end point of the measuring range, an adjustment light beam (11) having a third set of characteristics is generated.

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