DE102013022637B3 - Alignment element for an optical distance sensor, optical sensor arrangement and method for aligning an optical distance sensor - Google Patents

Abstract

Alignment element for an optical distance sensor (1), in particular an optical distance sensor (1) for determining a movement error of a rotary device, the alignment element (15) having or forming at least one irradiation surface (19), the alignment element (15) in the region of the irradiation surface ( 19) has a transmission opening (21) with a predetermined diameter, wherein the alignment element (15) has or forms at least one fastening means for fastening the alignment element (15) to the optical distance sensor (1), characterized in that the at least one fastening means is designed in such a way and/or is arranged relative to the transmission opening (21) in such a way that the optical distance sensor (1) has a desired orientation when a light beam (10) directed onto the irradiation surface passes at least partially from the side of the irradiation surface (19) through the transmission opening (21 ) occurs, with the irradiation surface (19) of the alignment lements (15), which has the transmission opening (21), is designed as a reflective surface or has a reflective surface, the reflective surface reflecting light rays from a predetermined spectral range.

Description

The invention relates to an alignment element for an optical distance sensor, in particular an optical distance sensor for measuring distances in a device for determining a movement error of a rotary device. The invention further relates to an optical sensor arrangement, in particular for determining a movement error of a rotary device, and a method for aligning such an optical distance sensor.

Optical sensors for measuring distances or measuring angle errors are known. The publication Probst et. al., "Measurement of angular and shape deviations on a mirror polygon surface with a phase interferometer", PTB-Mitteilungen 103 1/93, 1993 a so-called autocollimation telescope (AKF) for measuring angular errors.

For example, optical distance measuring sensors can measure a distance between the sensor and a target object. Such optical sensors can be designed, for example, as so-called transmitter-receiver sensors, with a transmitter of the sensor generating a light beam and a receiver of the sensor receiving the (reflected) light beam and determining the distance as a function of the received light beam.

It is also known to use optical sensors to determine a movement error of a rotary device. In this case, a rotary device designates a device, wherein at least one rotatable part of the rotary device can be rotated about an axis of rotation. Such rotary devices can be, for example, swivel joints or turntables.

During a rotation of the rotatable part of the rotary device about the axis of rotation, movement errors can occur which result from a deviation from an ideal, pure rotary movement. Such deviations are caused, for example, by a bearing of the rotatable part, a movement guidance of the rotatable part, due to manufacturing tolerances and/or by forces or moments acting in or on the axis of rotation. Such forces and moments can be static or dynamic forces or moments.

The term movement error here includes translational and rotational movement errors. Thus, when rotating around the axis of rotation, deviations from the ideal rotational movement can occur in six mutually independent degrees of freedom. In the case of multi-stage rotary devices, which therefore have a plurality of rotary axes, movement errors in one rotary axis may also be dependent on an angular position of the remaining rotary axis(s).

For this reason, it is customary to detect movement errors of a rotating device in order, for example, to be able to make a statement about the accuracy, in particular rotational accuracy, of the rotating device. Depending on the determined movement errors of the rotary device, the rotary device can also be calibrated, whereby, for example, systematic movement errors can be determined and then corrected by calculation. In particular, a movement error can be determined for certain or all angular positions of the axis of rotation. This movement error can thus be taken into account later, for example during operation of the rotary device. If the rotary axis is used, for example, to position a workpiece when machining or measuring the workpiece, the previously determined movement error can be taken into account when machining or measuring the workpiece. In particular, the movement error can be taken into account when measuring a workpiece using a coordinate measuring machine (CMM) in order to increase the measuring accuracy.

The subsequently published WO 2014/108 187 A1 discloses a method for determining one or more errors in a rotational position determination system. A test body or test element, in particular a rotationally symmetrical test element, and a sensor arrangement for determining the previously explained movement error of a rotary device are described here. The publication describes a sensor holder with three walls that are perpendicular to one another. Distance sensors are attached to the walls, which detect a distance between the distance sensors and the test element mentioned above. Depending on the output signals of these distance sensors, translational errors in three independent spatial directions as well as rotational errors in two independent spatial directions can be determined.

WO 2013/007 285 A1 discloses a correction and/or avoidance of errors when measuring coordinates of a workpiece. A measuring system is described herein which comprises a rod which carries two spherical measuring bodies which are arranged at a predetermined distance from one another in the axial direction. Also disclosed is an arm to which is attached an array of sensors. Here, a first sensor is directed toward an upper ball in the axial direction to measure a relative position in an axial direction. A second and third sensor are radially aligned with the upper sphere, where the sensors are aligned in different directions, for example perpendicular to one another, in order to measure radial relative positions in two different directions. A fourth and a fifth sensor are also aligned in two mutually perpendicular radial directions, but on the lower sphere to measure two independent relative radial positions at another axial position. The rod can be arranged concentrically or approximately concentrically to the axis of rotation to be measured on the rotatable part of the rotary device. The publication also describes how measurement signals from the sensors can be used to determine a relative position and/or orientation of the balls to one another and/or to determine and/or correct a change in the relative position and/or orientation of the balls.

The two documents thus describe how motion errors can be determined in five out of six degrees of freedom by using distance sensors.

When using optical distance sensors, e.g. to determine distances between the sensors and the spheres of the double-sphere standard explained above, the distance can be determined by emitting a (laser) light beam and reflecting the light beam on the test element. In this case, the alignment of an optical distance sensor relative to a target object, in particular the test element explained above, is essential, since if the alignment is imprecise, the reflected light beam falls only partially or not at all in a detection range of the optical sensor. In this case no reliable distance measurement is possible.

Aligning the optical sensor relative to the target object in such a way that the emitted light beam is reflected into the detection area of the optical sensor is usually very time-consuming. This means that a lot of time is needed to align the corresponding distance sensors before the actual distance detection for determining movement errors of the rotary device.

In particular, alignment with spherical or cylindrical targets is a major challenge. A further complication is that some optical distance sensors emit light rays in the non-visible spectral range, which makes visual alignment even more difficult.

the DE 197 46 535 B4 discloses an adjusting device for an interferometer, in which an alignment of an interferometer reference surface and a test object surface to be measured is required, the adjusting device comprising an adjusting element which is arranged in the focal plane of a collimator lens arranged in front of the test object surface, characterized in that on the adjusting element a two-dimensionally extended alignment mark is arranged and/or the alignment mark arranged on the adjustment element has a defined optical effect.

the DE 28 24 582 C3 refers both to a light barrier type in which the light emitter and light receiver are arranged on opposite sides of a monitored section, and to a light barrier type in which the light emitter and light receiver are arranged at one end of the monitored section, while a reflector provided at the other end of the monitored section, in particular, a retroreflector that reflects the light sent from the transmitter through the monitoring path back to the receiver.

the GB 2 117 511A discloses a laser beam detector and a method for aligning a laser.

the US 5,684,593A discloses an apparatus for aligning a reference reflector.

This results in the technical problem of creating an alignment element for an optical sensor, in particular for an optical distance sensor for determining a movement error of a rotary device, an optical sensor arrangement and a method for aligning an optical sensor, which aligns the optical sensor quickly and precisely relative to a target object.

The technical problem is solved by the objects with the features of claims 1, 6 and 8. Further advantageous configurations result from the dependent claims.

It is a basic idea of the present invention to create an alignment element for an optical sensor, in particular for an optical distance sensor for determining a movement error of a rotary device, which can be attached to the optical sensor in such a way that the optical sensor can be optimally aligned with the aid of the alignment element can be aligned with a light beam to be received. In particular, a light beam emitted by the optical sensor or a light source of the alignment element can only reach a detection range of the optical sensor if the light beam reflected by a target object is exactly on or with a predetermined ten slight deviation from the reflected light beam is reflected.

An alignment element for an optical distance sensor is proposed. The optical distance sensor can be used for distance measurement when determining a movement error of a rotary device. This is described in particular in the publications explained at the outset.

The optical distance sensor can detect a distance between the optical sensor and a target object, for example a test element or body, which is arranged on a rotatable part of a rotating device. This can be done, for example, by recording the runtime. However, the optical sensor is preferably a laser-interferometric sensor. Here, a distance between the sensor and the target object is detected by means of interferometry. In this case, a phase shift of a light beam reflected by the target object, in particular a reflected laser beam, or its modulation in relation to an emitted light beam is determined. This phase shift is distance-dependent, so that a distance between the optical sensor and the target object can be determined as a function of the phase shift.

Furthermore, the alignment element has at least one irradiation surface or forms one. In this case, the irradiation surface can be, for example, a flat surface or a part-spherical or hemispherical surface. In particular, the irradiation surface is an outer surface of the alignment element.

In the area of the irradiation surface, the alignment element has a transmission opening with a predetermined diameter. The predetermined diameter is determined as a function of a diameter of the emitted light beam, in particular larger than the diameter of the emitted light beam by a predetermined small amount, for example 10% larger than the diameter of the light beam. In this case, the diameter of the light beam can, for example, designate a light spot diameter which is specified, for example, by a manufacturer of the light source. The diameter of the light beam can depend in particular on the optics used. For example, if a parallel beam of light emerges, the diameter can be several centimeters. However, the diameter can preferably be in the μm or mm range.

For example, a diameter of the transmission opening can be 1 mm.

In relation to the irradiation surface, the light source for generating the light beam can be arranged on a side of the alignment element that faces away from the irradiation surface. The optical sensor, in particular a detection area of the optical sensor, can also be arranged on the side of the alignment element facing away from the irradiation surface. Thus, the irradiation surface designates an outer surface of the alignment element onto which light beams that are radiated, e.g. from the target object, towards the optical sensor can impinge.

According to the invention, the alignment element has or forms at least one fastening means for fastening the alignment element to the optical sensor. The fastening means serves to mechanically connect the alignment element to the optical sensor. In particular, the fastening means enables the production of a detachable mechanical connection, for example a frictional connection, in particular a clamp connection. However, fastening means are also conceivable which enable a further type of mechanical connection, for example a non-positive or a positive mechanical connection of the optical sensor to the alignment element. The connection is preferably a detachable mechanical connection.

Furthermore, the at least one fastening means is designed and/or arranged relative to the transmission opening in such a way that the optical sensor has a desired orientation when a light beam directed onto the irradiation surface passes through the transmission opening at least partially from the side of the irradiation surface.

The desired alignment of the optical sensor refers here to an alignment in which the optical sensor is aligned relative to the light beams to be detected in such a way that they can be detected, in particular can be detected with a predetermined signal quality. For example, in the desired orientation, a signal-to-noise ratio can be greater than -3dB.

A light beam passing through the transmission opening from the side of the irradiation surface preferably reaches a detection area of the sensor. In particular, the light beam can only reach a detection area of the sensor when it passes through the transmission opening from the side of the irradiation surface. In this case, the light beam is at the same time a light beam to be detected. It is possible here for the alignment element, in particular the irradiation surface, to cover part of the detection area of the sensor.

However, the light beam to be detected by the optical sensor can also run parallel or almost parallel to the light beam passing through the transmission opening from the side of the irradiation surface. In particular, the to be recorded In this case, the transmitted light beam runs outside the irradiation area. This can be the case, for example, if the alignment element is not intended to cover a detection area of the sensor and is therefore attached to the optical sensor in such a way that the desired alignment is given when a light beam passes through the transmission opening, but the detection area is not covered.

The light beam directed onto the irradiation surface can be generated by a light source that can be structurally separate from the optical sensor. In this case, the light source can be arranged with a predetermined positional difference and alignment difference from the optical sensor.

However, it is also possible for the optical sensor to include the light source. This is explained in more detail below.

In particular, the light beam directed onto the irradiation surface can be a light beam reflected, for example, from a target object. This is also explained in more detail below.

The alignment element described thus advantageously enables a desired alignment of the optical sensor by aligning the optical sensor with the alignment element attached to it in such a way that a light beam directed onto the irradiation surface and possibly to be detected passes at least partially through the transmission opening.

In a preferred embodiment, a light beam emitted by the optical sensor or a light source of the alignment element, which passes through the transmission opening on the side facing away from the irradiation surface, or a portion thereof, exclusively from the side of the irradiation surface through the transmission opening when the light beam enters or is almost reflected in itself.

This means that a light beam radiated through the transmission opening can only be reflected back through the transmission opening if the light beam is reflected in itself or almost in itself.

In this context, reflected in itself means that a beam direction of the reflected light beam is opposite to the beam direction of the emitted light beam, with the light beams running concentrically with one another. This means that (theoretical) center lines of the emitted and reflected light beam overlap. Thus, the light beam reflected from a target object is accurately reflected onto the emitted light beam.

Almost internally reflected means that the reflected light beam is reflected with a predetermined slight deviation from the emitted light beam, with the light beams no longer being ideally concentric with one another. The predetermined slight deviation can be characterized, for example, by an angle from an angular range of −1° to 1°. It is therefore possible for the center lines to also deviate slightly from one another, for example deviations of less than 1°, with the reflected light beam or a predetermined portion of the reflected light beam still passing through the transmission opening.

Preferably, a light beam emitted by the optical sensor or the light source of the alignment element, which passes through the transmission opening from a side facing away from the irradiation surface, or a predetermined portion of the reflected light beam then exclusively from the side of the irradiation surface through the transmission opening into a detection area of the optical sensor , when the light beam is reflected in itself or almost in itself.

If the emitted light beam is not reflected in itself or if it deviates from the emitted light beam by more than a predetermined amount, for example by more than 1°, the reflected light beam hits the irradiation surface and no longer passes through the surface with a sufficiently large proportion transmission aperture.

Thus, the reflected light beam only enters the detection range or measuring range of the optical sensor when the emitted light beam is reflected in itself. In particular, the reflected light beam reaches the detection area directly, i.e. without further reflection or scattering on other objects, from the target object. For example, the reflected light beam can strike a sensor surface, for example a CCD sensor surface, of the optical sensor through the transmission opening.

When attached to the optical sensor, the proposed alignment element advantageously enables the latter to be aligned relative to a target object, for example by visually monitoring the light beam reflected onto the irradiation surface, in such a way that a light beam emitted by the optical sensor or a light source of the alignment element is reflected in itself or almost in itself, which ensures that, for example, during a subsequent distance measurement, sufficient light enters the detection area of the optical sensor is reflected. Due to the fact that the light beam strikes the irradiation surface at an undesired angle in the event of reflection, the alignment can advantageously be visually supported. In particular, as explained in more detail below, the optical sensor and/or the target object can be positioned relative to one another in such a way that the reflected light beam or a predetermined proportion thereof passes through the transmission opening, thereby ensuring that the sensor is aligned as desired .

After the optical sensor has been aligned, the alignment element can be removed from the optical sensor again and a distance measurement can be carried out.

The alignment element thus enables the distance sensor to be aligned quickly relative to the target object.

In a further embodiment, the at least one fastening means is designed and/or arranged relative to the transmission opening in such a way that a central axis of the transmission opening corresponds to a central axis of symmetry of the detection area of the sensor. The detection range of the optical sensor can be cone-shaped, for example. This ensures that a light beam reflected through the transmission opening enters the detection area of the optical sensor as centrally as possible. If, after the alignment, e.g. during a subsequent measurement, (smaller) angle changes occur in the reflection of the emitted light beam, e.g. due to a subsequent change in the relative alignment between the optical sensor and the target object, this advantageously ensures that in this If reflected light can still reach the detection area of the optical sensor. A change in the alignment relative to one another can take place, for example, when the alignment element is released and/or when the target object is rotated. In particular, it can thus be ensured that even a light beam that is reflected at an angle that is smaller than a predetermined maximum angle is reflected into the detection range of the optical sensor, whereby a reliable distance measurement is still possible in this case.

It is also conceivable that the alignment element has a central longitudinal axis, with a central axis of the transmission opening being arranged on the central longitudinal axis of the alignment element. In particular, the alignment element can be rotationally symmetrical to the central longitudinal axis.

In a preferred embodiment, the alignment element is designed as a hollow cylinder, with the hollow cylinder having a first end face and a lateral surface. In this case, the transmission opening is arranged in the first end face. The first end face thus forms the irradiation surface. Furthermore, the hollow cylinder can be open toward the end face that is arranged opposite the first end face.

An inner diameter of the hollow cylinder can be selected in such a way that the alignment element can be plugged onto the optical sensor, in particular a fastening surface of the optical sensor. For this purpose, the inner diameter can be selected to be smaller by a predetermined amount than an outer diameter of a section of the sensor that forms the fastening surface.

In this case, the alignment element is therefore designed as an alignment sleeve. In this case, the hollow cylinder has an inner volume, in which case the optical sensor and/or the previously explained light source of the alignment element can be arranged in the inner volume.

In this way, mechanical protection of the optical sensor by the alignment element is advantageously provided at the same time as the alignment aid explained above. In particular, the alignment element designed as an alignment sleeve can protect the optical sensor from dirt and mechanical damage. The target object can also be protected from damage by the alignment sleeve if the optical sensor collides with the target object, e.g. during alignment. The alignment sleeve also enables safe storage of the sensor, with the sensor head being protected with a sensitive lens even during storage, for example.

The alignment element can be made at least partially of plastic, for example.

Alternatively or cumulatively, the alignment element can be attached to a sensor holder and thus not to the sensor itself.

According to the invention, the irradiation surface of the alignment element, which has the transmission opening, is designed as a reflection surface. In this case, the reflection surface reflects rays from a predetermined spectral range. In particular, the spectral range of the reflection surface of the alignment element includes a wavelength or a spectral range with which the light beam is emitted by the optical sensor or the light source of the alignment element and/or with which the emitted light beam is reflected by the target object. the predetermined spectral range can include, for example, wavelengths in a range from 1520 nm to 1610 nm. Of course, other wavelengths in the visible or non-visible range can also be used.

As will be explained in more detail below, this enables a visual or camera-based detection of a light beam that is radiated onto the irradiation surface and is therefore reflected by this irradiation surface. In this way, it can be detected in an advantageous manner whether the emitted light beam is reflected in itself.

In an embodiment not according to the invention, the reflection surface emits radiation with a predetermined spectral range when irradiated.

For example, the reflection surface can be a fluorescent or luminescent surface which, when irradiated with the reflected light beam, emits radiation with the predetermined spectral range. In this case, the reflection layer can be excited in particular with radiation in a wavelength range from 1500 nm to 1590 nm. The predetermined spectral range with which radiation is emitted from the reflection surface can differ from the wavelength or the spectral range with which the light beam is emitted by the optical sensor or the light source of the alignment element and/or is reflected by the target object. In particular, the predetermined spectral range with which the reflection surface emits radiation can include at least a partial range of the spectral range of visible light. If the optical sensor or the light source of the alignment element emits a light beam with a wavelength or a spectrum in the non-visible range, the reflection surface designed in this way can advantageously convert it into visible light, which enables visual detection and thus alignment, e.g simplified a user.

In embodiments that are not according to the invention, the irradiation surface of the alignment element, which has the transmission opening, is designed as a sensor surface. For example, the irradiation surface can be designed as a CCD array or can include such a CCD array. Of course, other sensors, in particular sensors that can be formed over an area, can also be used to detect radiation.

In particular, the sensor surface enables an intensity of a light beam impinging on the sensor surface and/or a position of the light beam in a sensor-specific coordinate system to be detected. If a position of the transmission opening is also known in the sensor's own coordinate system, then a distance and a direction of the light beam impinging on the reflection surface can be determined relative to the transmission opening.

The sensor surface can, for example, detect light in a predetermined spectral range, the spectral range comprising a wavelength or a spectral range with which the optical sensor or the light source of the alignment element emits light or with which light is reflected from the target object.

The sensor surface can be connected in terms of data to an evaluation device. As explained above, the evaluation device can in turn determine the position of the light beam on the sensor surface relative to the transmission opening. Furthermore, the evaluation device can control a display device in such a way that the information explained above can be displayed to a user, for example.

As explained in more detail below, the evaluation device can also control a positioning device of the optical sensor and/or the target object in such a way that the optical sensor and the target object are positioned relative to one another in such a way that the light beam reflected by the target object passes through the transmission opening.

In a further embodiment, the alignment element comprises at least one light source. The light source is designed and/or arranged in such a way that at least part of the light beam generated by the light source passes through the transmission opening from a side facing away from the irradiation surface.

In this case, the light beam can have a predetermined maximum diameter, which in particular can be smaller than or equal to a diameter of the transmission opening. However, it is also conceivable that the diameter of the light beam is larger than the diameter of the transmission opening.

In this case, the light source can be mechanically fastened to the alignment element. In particular, the light source can be arranged in the previously explained inner volume of the alignment sleeve. A beam direction of the light beam generated with the light source can be parallel to the central axis of the transmission opening or can overlap with it.

In a first alternative, the light source is used for illumination. In this case, the light source can be switched on and off. preferred In this case, the light source can be dimmable. This advantageously facilitates alignment in a dark environment, since the transmission opening is illuminated by the light source, light exiting through the transmission opening. This makes it possible to detect a position of the transmission opening visually, for example by a user. Thus, a light beam reflected onto the irradiation surface can be guided to the transmission opening in a simplified manner by aligning the optical sensor relative to the target object.

Alternatively or cumulatively, the light source can be used to generate a light beam that is emitted through the transmission opening, with the transmission opening being arranged relative to the light source in such a way that the light beam reflected by a target object only passes through the transmission opening again when the emitted light beam is in is reflected in itself or almost in itself.

Thus, as already explained above, the light beam that is used to align the optical sensor can be generated either by the optical sensor itself or by the light source that is structurally separate from the optical sensor. In this case, the proposed alignment element can also be used to align optical sensors or other sensors. For example, the alignment element can be used to align an optical sensor for angle measurement, in particular a so-called autocollimation telescope (AKF).

An autocollimation telescope can measure changes in the angle of an object. For this purpose, a reflector, for example a mirror, is attached to the object. The autocollimator has a light source that emits a beam of light. The light beam is directed onto the mirror, reflected by the mirror and focused onto a detector. If the object tilts, the focus on the detector moves.

In this case, however, ACFs only have a very small angular range in which reliable detection is possible. The alignment element can thus be used in an advantageous manner to position an AKF relative to a target object to be measured in such a way that this target object is oriented in a detectable angular range to the AKF.

For example, it is conceivable that the AKF has corresponding fastening elements that interact with the fastening elements of the alignment element in order to fasten the alignment element to an AKF in such a way that a light beam emitted by the light source of the alignment element is oriented parallel to light rays of the AKF . In this case, the alignment element can be plugged onto the AKF, for example, with a lens of the AKF being at least partially covered. In this case, the AKF can first be aligned relative to the target object to be measured, in which case it is then necessary to remove the alignment element again It is also possible to design the alignment element, in particular the irradiation surface, in such a way that it does not cover a detection area of the AKF completely or not covered by more than a predetermined amount. For this purpose, it is possible, for example, to design the irradiation surface to be smaller than the diameter of a lens or an objective of the AKF. It is also conceivable that the irradiation surface has further openings. For example, a portion of the alignment element having the irradiation surface can be spoke-shaped. In this case, alignment takes place using the transmission opening explained above, while the other openings enable measurement using the AKF.

As a further alternative, the alignment element can be attached to the AKF in such a way that simultaneous alignment and measurement is possible. For this purpose, the alignment element can be attached to an outer surface of the AKF, for example.

An optical sensor arrangement is also proposed, in particular for determining a movement error of a rotary device. The sensor arrangement comprises at least one optical sensor, in particular a distance sensor, in particular an interferometric distance sensor. Furthermore, the optical sensor arrangement comprises at least one alignment element according to one of the previously described embodiments.

The alignment element is arranged on the optical sensor by means of the at least one fastening means for fastening the alignment element in such a way that the optical sensor has a desired alignment when a light beam directed onto the irradiation surface passes through the transmission opening at least partially from the side of the irradiation surface. In particular, a light beam emitted by the optical sensor or a light source of the alignment element, which passes through the transmission opening from a side facing away from the irradiation surface, or a predetermined portion thereof can only pass through the transmission opening from the side of the irradiation surface if the light beam enters or is almost reflected in itself.
In particular, in this case the reflected light beam can pass through the transmission opening into a detection area of the optical sensor.

In this case, the optical sensor can have corresponding fastening means which interact with the at least one fastening means of the alignment element in such a way that the arrangement described above can be produced. In particular, the fastening means of the alignment element and the corresponding fastening means of the optical sensor enable the alignment element to be fastened centrally on the sensor, with a central axis of the transmission opening corresponding to a central beam direction of the optical sensor or the light source of the alignment element. Thus, a beam direction of the optical sensor or the light source of the alignment element can be parallel to the central axis of the transmission opening. If the optical sensor emits the light beam, in particular if the optical sensor is designed as a transmitter-receiver sensor, the result is advantageously that the distance measurement and the alignment proposed according to the invention can take place simultaneously when using the optical sensor, since the distance measurement and the Alignment uses the same light source. Alternatively, as explained above, a light source that is structurally separate from the optical sensor can be used to emit the light beam for alignment.

In this case, the optical sensor can emit and receive a light beam with a predetermined wavelength or a wavelength from a predetermined spectral range.

Here, the optical sensor can be attached to a sensor holder. Thus, the proposed optical sensor arrangement can also include such a sensor holder.

The proposed optical sensor arrangement advantageously enables simple and quick alignment of the optical sensor relative to a target object. In particular, by observing the irradiation surface and a light beam reflected onto the irradiation surface, the optical sensor can be positioned relative to the target object in such a way that the reflected light beam passes through the transmission opening and can thus optimally enter a detection area of the optical sensor. With such an alignment it is ensured that a sufficient signal for distance measurement is generated in a subsequent distance measurement.

In a further embodiment, the optical sensor arrangement comprises at least one image acquisition device. This can be designed as a camera, for example. The image capturing device is arranged in such a way that the irradiation surface is arranged in a capturing area of the image capturing device. The image acquisition device can thus image the irradiation surface and in particular a light beam reflected from the target object onto the irradiation surface. This advantageously enables an image-based determination of a position of a reflected light beam relative to the transmission opening.

This information or the image generated by the image acquisition device can, as previously described, be presented to a user on a display device, for example. In this case, the image acquisition device can image light from a predetermined spectral range. The spectral range with which the image acquisition device can image objects can include the wavelength or the spectral range with which the optical sensor or the light source of the alignment element emits the light beam or with which the light beam is reflected by the target object. This advantageously results in the fact that non-visible light can also be used in order to align the optical sensor relative to the target object, since the non-visible light can be represented visually by a corresponding image capturing device for a user.

Alternatively or cumulatively, the sensor arrangement comprises at least one positioning means for aligning the optical sensor relative to a target object. In particular, the optical sensor arrangement can include a positioning means for aligning the optical sensor.

For example, the optical sensor can be attached to a positioning device that can be adjusted by a motor, for example a CNC-controlled displacement frame. The optical sensor can be positioned in at least one spatial direction, preferably in three mutually independent spatial directions, by means of the at least one positioning means. An orientation of the optical sensor, e.g. by rotation about one or more spatial directions, can also be adjusted by the positioning means.

Alternatively or cumulatively, the target object can also be positionable by means of a positioning means. The same explanations as for the positioning means of the optical sensor apply to such a positioning means.

In this case, the optical sensor arrangement can also include a control and evaluation device, with the evaluation device being able to determine a position of a light beam reflected by the target object relative to the transmission opening, with the control device activating the at least one positioning means depending on this relative position in such a way that the Target object reflected light beam through the transmission aperture kicks. For example, the evaluation device can be used to determine a distance and a direction, eg in polar coordinates, of the reflected light beam or a geometric center point of the reflected light beam from a center of the transmission opening. Depending on the direction and the distance, the control device can then control the at least one positioning means in such a way that the distance between the light beam and the transmission opening is minimized, preferably reduced to zero.

For this purpose, the reflected light beam can be detected in particular in a sensor-based manner. For example, the light beam can be detected by means of an irradiation surface designed as a sensor surface. Alternatively, as explained above, the light beam can be captured by means of an image capturing device.

If the optical sensor is attached to a sensor holder, the positioning means can also be used to position the sensor holder.

The positioning means can also be designed as a CMM. For this purpose, for example, the sensor holder can be positioned using the CMM.

Because the optical sensor and/or the target object can be positioned by a controllable positioning means, controlled alignment can advantageously take place, with a control difference being given, for example, by the previously explained distance between the light beam and the transmission opening. This allows the alignment process to be further accelerated.

A method for aligning an optical sensor relative to a target object is also proposed. In this case, the optical sensor can in particular be a sensor for determining a movement error of a rotary device. In this case, an alignment element according to one of the previously described embodiments is arranged on the optical sensor such that the optical sensor has a desired alignment when a light beam directed onto the irradiation surface passes through the transmission opening at least partially from the side of the irradiation surface. Furthermore, a light beam is generated and directed onto the irradiation surface. Furthermore, the optical sensor and/or the light beam are aligned relative to one another depending on a position of the light beam on the irradiation surface in such a way that at least a predetermined portion of the light beam shines through the transmission opening.

In particular, the alignment element can be arranged on the optical sensor in such a way that a light beam emitted by the optical sensor or a light source of the alignment element, which passes through the transmission opening from a side facing away from the irradiation surface of the alignment element, or a predetermined proportion thereof, exclusively from the Side of the irradiation surface occurs through the transmission opening when the light beam is reflected in itself. In particular, the reflected light beam can enter the detection range of the optical sensor. Furthermore, a light beam is generated and reflected from the target object. Furthermore, the optical sensor and/or the target object is aligned relative to one another depending on a position of the reflected light beam on the irradiation surface in such a way that a predetermined proportion of the light beam reflected by the target object shines through the transmission opening. Here, both the sensor and the target object can be aligned. This can be done by manual positioning, e.g. by a user. Also, only the target object or only the sensor can be aligned. However, the alignment can also be carried out by a positioning means, in particular a motor-driven adjustable positioning means.

A sensor-based or image-based detection of the reflected light beam, a determination of the position of the light beam relative to the transmission opening and an alignment depending on this relative position, in particular by means of the previously explained positioning means, can take place. A distance and a direction of the light beam reflected onto the irradiation surface from the transmission opening can also be determined, for example in a polar coordinate system whose center is a center point of the transmission opening. The alignment can then take place, for example, as a function of the distance and the direction.

An intensity of the light beam reflected onto the irradiation surface can be determined, for example, during the sensor-based or image-based evaluation. An alignment process can be ended, for example, when the light beam reflected onto the irradiation surface has been positioned relative to the transmission opening in such a way that the intensity is less than a predetermined intensity, preferably zero.

In this case it can be assumed that all or a predetermined portion of the reflected light beam passes through the transmission opening.

This termination criterion allows reliable alignment in an advantageous manner, since if the reflected light beam passes through the transmission opening, there is usually no more reflected light beam on the irradiation surface, for example by a sensor or an image acquisition device can be acquired. Accordingly, alignment can be performed as long as an intensity of the light beam reflected onto the irradiation surface is greater than or equal to the predetermined intensity.

Of course, it must be taken into account here that the light beam can also be reflected next to the irradiation surface, it also being possible for no light beam reflected onto the irradiation surface to be detected. It must therefore also be ensured that before the alignment process is completed, e.g. the distance between the light beam reflected onto the irradiation surface and the transmission opening has been reduced.

• 1 eine schematische Seitenansicht eines optischen Sensors und eines Zielobjekts bei nicht optimaler Ausrichtung,
• 2 eine schematische Seitenansicht eines optischen Sensors und eines Zielobjekts bei optimaler Ausrichtung,
• 3 eine schematische Seitenansicht einer erfindungsgemäßen Sensoranordnung bei nicht optimaler Ausrichtung,
• 4 eine schematische Seitenansicht einer erfindungsgemäßen Sensoranordnung bei optimaler Ausrichtung,
• 5 eine schematische Seitenansicht einer weiteren erfindungsgemäßen Sensoranordnung,
• 6 einen Querschnitt durch eine Sensoranordnung,
• 7 einen Querschnitt durch ein Ausrichtelement,
• 8 ein schematischer Querschnitt durch eine weitere optische Sensoranordnung,
• 9 eine perspektivische Ansicht eines Sensors,
• 10 eine perspektivische Ansicht eines erfindungsgemäßen Ausrichtelements
• 11 eine perspektivische Ansicht einer Sensoranordnung und
• 12 eine optische Sensoranordnung zur Ausrichtung von fünf optischen Sensoren relativ zu einem Zielobjekt

The invention is explained in more detail using several exemplary embodiments. The figures show:

• 1 a schematic side view of an optical sensor and a target object with non-optimal alignment,
• 2 a schematic side view of an optical sensor and a target object with optimal alignment,
• 3 a schematic side view of a sensor arrangement according to the invention with non-optimal alignment,
• 4 a schematic side view of a sensor arrangement according to the invention with optimal alignment,
• 5 a schematic side view of a further sensor arrangement according to the invention,
• 6 a cross section through a sensor arrangement,
• 7 a cross section through an alignment element,
• 8th a schematic cross section through another optical sensor arrangement,
• 9 a perspective view of a sensor,
• 10 a perspective view of an alignment element according to the invention
• 11 a perspective view of a sensor arrangement and
• 12 an optical sensor array for aligning five optical sensors relative to a target object

In the following, the same reference symbols designate elements with the same or similar technical features.

In 1 A schematic side view of an optical sensor 1 and a target object 2 is shown. The target object 2 is in the form of a so-called spherical standard. The ball standard comprises at least one ball 3 and a rod 4, at the end of which the ball 3 is attached. As explained in more detail below, such a spherical standard is used to determine movement errors when rotating a rotatable part of a rotary device about an axis of rotation. For this purpose, the ball standard is arranged as concentrically as possible to the axis of rotation on the rotatable part of the rotating device. Concentric means that a center line 5 of the sphere normal is arranged on the axis of rotation.

The sensor 1 includes a light source and a light receiver, which can be arranged in a housing 6 of the sensor 1 . A lens 8 is arranged in a sensor head 7 . A light beam 9 generated by the light source of the sensor 1 is emitted through this lens 8 .

In 1 a coordinate system is also shown, with a vertical direction z and a first horizontal direction x being shown. A beam direction of the light beam 9 is oriented opposite to the vertical direction z. The light beam 9 can have a predetermined diameter. In particular, the light beam 9 can be a laser beam.

In 1 it is shown that a center line of the light beam 9 does not intersect a center point M of the sphere 3 . Thus, the light beam 9 does not strike a pole of the sphere 3. This means that the light beam 9 is reflected at an angle α from a predetermined angle range. The light beam 10 reflected by the ball 3 is therefore not reflected back to the lens 8 and thus not into a detection area 11 of the optical sensor 1 . In 1 It is shown that in such a non-optimal alignment of the optical sensor 1 to the target object 2, the reflected light beam 10 is additionally scattered, with a diameter of the light beam 10 being widened.

In 2 is the in 1 shown arrangement shown in an optimal orientation. In this case, the optical sensor 1 is arranged relative to the target object 2 in such a way that a center line of the light beam 9 intersects a center point M of the sphere 3 of the target object 2 . Thus, the center line of the light beam 9 is superimposed on a radial line of the sphere 2.

In this case, the light beam 9, which is emitted by the light source of the optical sensor 1 through the lens 8, is reflected on itself. in the in 2 illustrated embodiment is thus a beam direction of the reflected beam 10 in Oriented in the vertical direction z, with center lines of the light beams 9, 10 being superimposed. The reflected light beam thus reaches the detection area 11 of the optical sensor 1 completely, which makes it possible to determine the distance reliably and precisely.

In 1 and 2 is shown that a holding device 12 for fastening the optical sensor 1 to a sensor holder 35 (see FIG 12 ) is arranged. Furthermore, the sensor head 7 has a cylindrical section 13 with a predetermined outer diameter and a conical section 14, at the narrow end of which the lens 8 is arranged. The cylindrical section 13 of the sensor head 7 serves as a fastening means of the optical sensor 1 for fastening an alignment element 15 (see e.g 3 ) on the optical sensor 1.

In 3 a schematic side view of an optical sensor arrangement 16 is shown. The sensor arrangement 16 comprises an optical sensor 1 which, in accordance with the 1 explained optical sensor 1 is formed. Furthermore, the sensor arrangement 16 comprises an alignment element 15. The alignment element 15 is in the form of a hollow cylinder. In this case, the alignment element 15 has a jacket section 17 and a first end face 18 . An outer surface of the end face 18 is designed as an irradiation surface 19 . Alignment element 15 encloses an interior volume 20 . In this case, the irradiation surface 19 designates the surface of the end face 18 which faces away from the inner volume 20 . The end face 18 has a penetration opening 21 . The inner volume 20 is accessible from the outside through the transmission opening 21 . It is shown here that the sensor head 7 and in particular the lens 8 are arranged in the inner volume 20 .

In this case, the hollow cylinder has an inner diameter which is smaller by a predetermined amount than an outer diameter of the cylindrical section 13 of the sensor head 7 . The alignment element 15 can thus be plugged onto the sensor head 7 and held in place. A frictional connection between the sensor head 7 and the alignment element 15 can thus be produced. Thus, inner surfaces of the jacket section 17 of the alignment element 15 form the fastening means of the alignment element 15 for fastening to the optical sensor 1. However, it is also conceivable that the inner diameter of the hollow cylinder is larger than the outer diameter and the alignment element 15 can be fixed by means of a fastening means, e.g. a screw. is attached to the sensor head 7.

The illustrated attachment of the alignment element 15 to the optical sensor 1 is carried out in such a way that a central axis of the transmission opening 21 corresponds to a center line of the emitted light beam 9, i.e. is arranged on this. In particular, the alignment element 15 is arranged concentrically to the light beam 9 on the optical sensor 1 .

A diameter of the transmission opening 21 is chosen such that the light beam 9 passes through the transmission opening 21 from a side of the end face 18 facing away from the irradiation surface 19 . Furthermore, the diameter of the transmission opening 21 is selected in such a way and the alignment element 15 is fastened to the optical sensor 1 in such a way that the light beam 10 reflected by the target object 2 is only reflected back through the transmission opening 21 from the side of the irradiation surface 19 when the light beam 9 is in itself or is almost reflected in itself. In 3 is, accordingly 1 , shown that a center line of the light beam 9 does not intersect a center point M of the sphere 3 . Thus, the light beam 9 is reflected at the angle α. A part of the reflected light beam 10 thus strikes the irradiation surface 19 in a region 22.

It can thus be detected visually or, as explained in more detail below, also based on sensors or cameras, that the light beam 9 is not reflected in itself but at an angle that is greater than a predetermined desired angle from the target object 2 .

In 4 is the in 3 shown arrangement shown at an optimal alignment. How to 2 already explained, in this case the optical sensor 1 is arranged relative to the target object 2 in such a way that a center line of the emitted light beam 9 intersects a center point of the sphere 3 of the target object 2 . Thus, the light beam 9 is reflected in itself and the reflected light beam 10 re-emerges from the side of the irradiation surface 19 through the transmission opening 21 into the detection area of the optical sensor 1, in particular onto the lens 8. In this case, the reflected light beam 10 does not hit or only hits partially on the irradiation surface 19. In this case, it can be visually observed or detected by sensors or cameras that no reflected light beam 10 hits the irradiation surface 19, from which it can be concluded that the target object 2 is optimally aligned relative to the optical sensor 1 is.

In 5 Another schematic side view of a proposed optical sensor assembly 16 is shown. As in 3 shown, the sensor arrangement 16 comprises an optical sensor 1 and an alignment element 15. A target object 2 and the optical sensor 1 are arranged relative to one another here in such a way that a center line of an emitted light beam 9 does not intersect a center point M of the sphere 3 of the target object 2. Thus is the optical sensor 1 is not optimally aligned with the target object 2. In contrast to that in 3 The sensor arrangement 16 described has an image acquisition device 23. The irradiation surface 19 is here arranged in a detection area 24 of the image acquisition device 23. A light beam 10 reflected onto the irradiation surface 19 and impinging on this irradiation surface in a region 22 can thus be detected by the image acquisition device 23 . If such a light beam 10 reflected onto the irradiation surface 19 is detected, it can be detected, for example, using a camera, that the optical sensor 1 is not optimally aligned with the target object 2 .

Output signals from the image capture device 23 can be used for automatic alignment. In particular, depending on the image generated by the image acquisition device 23, a distance and a direction of the region 22, in which the reflected light beam 10 falls, from the transmission opening 21 can be determined. The direction can be determined, for example, in a suitable coordinate system, for example a polar coordinate system. Suitable methods of image processing, e.g. detection or segmentation methods, can be used for this. These can be carried out based on intensity, for example. It can be taken into account here, for example, that the imaged irradiation surface 19 has a higher intensity in area 22 than in the remaining areas of irradiation surface 19.

The distance and the direction determined based on the image can then be used to control, for example, a motorized positioning device (not shown) of the optical sensor 1 and/or the target object 2. Depending on the distance and the direction, the optical sensor 1 is positioned relative to the target object 2 in such a way that the reflected light beam 10 passes through the transmission opening 21 into the detection range of the optical sensor 1 .

In 6 a schematic cross section through a further optical sensor arrangement 16 according to the invention is shown. The optical sensor arrangement 16 in turn comprises an optical sensor 1 with a sensor head 7, onto which an alignment element 15, which is already shown in 3 was explained, is plugged. It is shown here that a luminescent layer 25 is arranged on the end face 18 of the hollow-cylindrical alignment element 15 . The transmission opening 21 extends through the end face 18 and the luminescent layer 25. An outer surface of the luminescent layer 25 forms the irradiation surface 19. If a light beam strikes the luminescent layer 25, the luminescent layer 25 fluoresces and thus generates radiation, in particular radiation in one spectral range of visible light.

It is also shown that in an inner volume 20 of the alignment element, ie on the side of the alignment element 15 facing away from the irradiation surface 19, a further light source 26 is arranged, which can be supplied with energy through supply lines 27. In this case, the light source 26 can be in the form of an LED, for example. The interior volume 20 can be illuminated by means of the additional light source 26 . In this case, light passes through the transmission opening 21 from the side facing away from the irradiation surface 19. Thus, a position of the transmission opening 21, in particular in the dark, can be better detected visually or based on a camera or sensors.

This enables simplified alignment even in the dark.

In 7 a schematic cross section through an alignment element 15 according to the invention is shown. This alignment element 15 is also in the form of a hollow cylinder and comprises a casing section 17 and an end face 18. An outer surface of the end face 18 forms the irradiation surface 19 explained above. Here, as in the previous examples, the hollow-cylindrical alignment element 15 is open to a side that is arranged opposite the first end face 18 . It is shown here that the alignment element 15 includes a light source 28 . In this case, the light source 28 differs from the light source of the optical sensor 1 .

The light source 28 is arranged within the inner volume 20 of the alignment element 15 in such a way that a light beam 9 emitted by the light source 28 passes through the transmission opening 21 from the side facing away from the irradiation surface 19 and is only then reflected back through the irradiation opening 21 from the side of the irradiation surface 19 , when the emitted beam 9 is reflected in itself or almost in itself.

This in 7 The alignment element 15 shown can be used to align distance sensors.

In 8th a cross section through a further optical sensor arrangement 16 is shown. This is in 7 The alignment element 15 shown is attached to a so-called autocollimation telescope 29 (AKF). Here, the AKF 29 forms an optical sensor. In this case, the jacket section 17 is slipped onto a free end of an objective 30 of the AKF. The AKF 29 is used to measure angles of rotation, in particular of mirrors 31. Here, the AKF 29 can only have a relatively small angle capture the angular range. It is therefore desirable, before starting a measurement, to align the AKF 29 in such a way that the light reflected by the mirror 31 radiates into the detection area of the AKF 29 . For alignment, the casing section 17 of the alignment element 15 can be pushed onto the lens 30, with the light beam 9 emitted by the light source 28 running parallel to the light beams to be detected by the AKF, in particular parallel to a central longitudinal axis of the lens 30. The parallel alignment can can alternatively or additionally be achieved by aligning as a function of markings, the markings being attached to the lens 30 and/or the alignment element 15 .

As already explained above, the alignment can take place by positioning the ACF 29 and/or the mirror 31 relative to one another, with the alignment being set in such a way that the emitted light beam 9 is reflected in itself by the mirror element 31 . In 8th it is shown that the reflected light beam 10 is not reflected into the emitted light beam 9, but falls on the irradiation surface 19 in the area 22. Thus, the AKF 29 is not optimally aligned relative to the mirror 31.

In 9 a perspective view of the optical sensor 1 for distance measurement is shown. This optical sensor 1 comprises a sensor housing 6 and a sensor head 7 which has a cylindrical section 13 .

In 10 an alignment element 15 designed as an alignment sleeve is shown. It can be seen here that a jacket section 17 of the alignment element 15 is designed differently from an end face 18 , the end face 18 having the irradiation surface 19 with the irradiation opening 21 . Also shown is a through hole 32 through which, for example, the 6 illustrated leads 27 can be performed.

In 11 an optical sensor arrangement 16 is shown in which the alignment element 15 is plugged onto the optical sensor 1 . In this configuration, the sensor head 7, in particular the lens 8 (see e.g 3 ), Protected by the alignment element 15, for example, from environmental influences.

In 12 an optical sensor arrangement 16 for aligning a total of 5 optical sensors 1 relative to a target object 2 is shown. The target object 2 is designed as a so-called double sphere standard. The double ball standard comprises a cylindrical rod 4, with a first ball 3a and a second ball 3b being arranged along a longitudinal axis of the cylindrical rod 4. In 12 it is shown that the double sphere standard is arranged on a rotatable part 33 of a turntable 34, the double sphere standard being arranged concentrically or almost concentrically on a non-illustrated axis of rotation of the rotatable part 33. In order to detect the initially explained movement errors of the axis of rotation of the rotatable part 33, distances of the optical sensors 1 from the balls 3a, 3b are measured during a rotation of the rotatable part 33. In this case, two optical sensors 1 detect distances in a first horizontal direction x and a second horizontal direction y from the first sphere 3a, the horizontal directions x, y being oriented perpendicular to one another. Two of the five optical sensors 1 detect distances in the two horizontal directions x, y from the second sphere 3b. A remaining optical sensor 1 detects a distance of the optical sensor 1 from the second ball 3b in the vertical direction z. It is shown here that the optical sensors 1 are attached to a sensor holder 35 . The sensor holder 35 comprises three walls which are perpendicular to one another, with two optical sensors 1 being fastened to the side walls and one optical sensor 1 being fastened to an end wall. The optical sensors 1 can be attached, for example, by means of the in 1 described holding device 12 take place. The sensor holder 35 can be positioned by a motor in the three spatial directions x, y, z by a positioning means 36 . Alignment elements 15 are attached to a sensor head (not shown). The positioning means 36 aligns the sensor holder 35 and thus all five sensors 1 relative to the spheres 3a, 3b in such a way that light beams 9 emitted by the optical sensors 1 for distance measurement (see, for example, 3 ) from the balls 3a, 3b, which in this case form target objects, are reflected in themselves or almost in themselves.

For a subsequent distance measurement during a rotation of the rotatable part 33, alignment elements 15 are used by the sensor heads 7 (see e.g 3 ) subtracted. However, it is also possible for the alignment elements 15 to be attached to the sensor heads 7 during the measurement. The previous alignment thus advantageously ensures that the reflected light beam 10 (see e.g 4 ) is reflected into the detection range of the optical sensors 1.

Reference List

1

optical sensor

2

target object

3

Bullet

4

Rod

5

central axis

6

Housing

7

sensor head

8th

lens

9

beam of light

10

reflected light beam

11

Detection range of the optical sensor

12

holding device

13

cylinder section

14

conical section

15

alignment element

16

optical sensor array

17

coat section

18

face

19

irradiation surface

20

internal volume

21

transmission aperture

22

area

23

image capture device

24

detection range

25

luminous surface

26

light source

27

supply lines

28

another light source

29

autocollimation scope

30

lens

31

mirror

32

Hole

33

rotating part

34

turntable

35

sensor holder

36

positioning means

a

angle

x

first horizontal direction

y

second horizontal direction

e.g

vertical direction

M

Focus

Claims (8)

Alignment element for an optical distance sensor (1), in particular an optical distance sensor (1) for determining a movement error of a rotary device, the alignment element (15) having or forming at least one irradiation surface (19), the alignment element (15) in the region of the irradiation surface ( 19) has a transmission opening (21) with a predetermined diameter, wherein the alignment element (15) has or forms at least one fastening means for fastening the alignment element (15) to the optical distance sensor (1), characterized in that the at least one fastening means is designed in such a way and/or is arranged relative to the transmission opening (21) in such a way that the optical distance sensor (1) has a desired orientation when a light beam (10) directed onto the irradiation surface passes at least partially from the side of the irradiation surface (19) through the transmission opening (21 ) occurs, wherein the irradiation surface (19) of the alignment element (15), which has the transmission opening (21), is designed as a reflective surface or has a reflective surface, the reflective surface reflecting light beams from a predetermined spectral range. alignment element claim 1 , characterized in that the at least one fastening means is designed and/or arranged relative to the transmission opening (21) in such a way that a light beam (9) emitted by the optical distance sensor (1) or a light source (28) of the alignment element (15) the side facing away from the irradiation surface (19) passes through the transmission opening (21), or a portion thereof, exclusively from the side of the irradiation surface (19) through the transmission opening (21) when the light beam (9) enters or is almost reflected in itself. alignment element claim 1 or 2 , characterized in that the at least one fastening means is designed and/or arranged relative to the transmission opening (21) in such a way that a central axis (5) of the transmission opening (21) corresponds to a central axis of symmetry of a detection region (11) of the optical distance sensor (1). . Alignment according to one of Claims 1 until 3 , characterized in that the alignment element (15) is designed as a hollow cylinder, the hollow cylinder having a first end face (18) and a jacket section (17), the transmission opening (21) being arranged in the first end face (18), the hollow cylinder to the front side, which is arranged opposite the first end face (18), is open. Alignment according to one of Claims 1 until 4 , characterized in that the alignment element (15) comprises at least one light source (28), the light source (28) being designed and/or arranged in such a way that at least part of the light beam (9) generated by the light source (28) is directed by a the side facing away from the irradiation surface (19) passes through the irradiation opening (21). Optical sensor arrangement, in particular for determining a movement error of a rotary device, the sensor arrangement (16) having at least one optical distance sensor (1) and at least one alignment element (15) according to one of Claims 1 until 5 comprises, wherein the alignment element (15) is fastened to the optical distance sensor (1) by means of the at least one fastening means for fastening the alignment element (15) in such a way that the optical distance sensor (1) has a desired alignment when a beam is projected onto the irradiation surface (19 ) directed light beam passes at least partially from the side of the irradiation surface (19) through the transmission opening (21). Optical sensor arrangement claim 6 , characterized in that the optical sensor arrangement (16) comprises at least one image capturing device (23), the image capturing device (23) being arranged in such a way that the irradiation surface (19) is arranged in a capturing area (24) of the image capturing device (23) and/ or the optical sensor arrangement (16) comprises at least one positioning means (36) for aligning the optical distance sensor (1) with a target object (2). Method for aligning an optical distance sensor (1), in particular an optical distance sensor (1) for determining a movement error of a rotating device, relative to a target object (2), wherein an aligning element (15) according to one of Claims 1 until 5 is arranged on the optical distance sensor (1) in such a way that the optical distance sensor (1) has a desired orientation when a light beam (10) directed onto the irradiation surface (19) passes at least partially from the side of the irradiation surface (19) through the transmission opening ( 21), a light beam (9) being generated and directed onto the irradiation surface (19), the optical distance sensor (1) and/or the light beam (9) depending on a position of the light beam (9, 10) on the irradiation surface (19) are aligned relative to one another in such a way that a predetermined proportion of the light beam (10) shines through the transmission opening (21).

Images