OPTICAL SENSOR

Abstract

The invention relates to an optical sensor with at least one light beam emitting transmitter (5), at least one light beam receiving receiver (6), and an evaluation unit configured for evaluating received signals from the at least one receiver (6). The optical sensor has two sensor units (1a, 1b, 8a, 8b) arranged at a distance from one another, with the light beams (4) passing between the sensor units (1a, 1b, 8a, 8b). A mechanical alignment structure (7a, 7b) is provided on at least one side wall of at least one sensor unit (1a, 1b, 8a, 8b), which forms a target geometry (12) that can be aimed at and extends in the direction of an optical axis of this sensor unit (1a, 1b, 8a, 8b).

Description

[0001] The invention relates to an optical sensor and a method for operating an optical sensor.

[0002] Such optical sensors can be used to detect objects in a monitored area. Examples of such optical sensors include light curtains and light barriers.

[0003] In both cases, the optical sensor has two sensor units located at opposite edges of the monitored area. The first sensor unit contains the transmitter(s) of the optical sensor that emits light beams. The second sensor unit contains the receiver(s) that receive the light beams, as well as an evaluation unit for evaluating the received signals from the receiver(s).

[0004] Such optical sensors operate according to the light barrier principle. When the monitoring area is clear, the light beams of the transmitter(s) strike a receiver assigned to it without obstruction. If an object enters the monitoring area, the light beams of the transmitter(s) are interrupted, which is registered in the evaluation unit. The evaluation unit generates an object detection signal based on the received signals from the receiver(s). The object detection signal is, in particular, a binary switching signal whose switching states indicate whether an object is present in the monitoring area or not.

[0005] Before the optical sensor is operated, in which object detection is carried out in the monitored area, the sensor units must be adjusted so that the light beams of the transmitter(s) are directed towards the assigned receiver(s).

[0006] This adjustment is made more difficult because the transmitter(s) typically emit light rays in the non-visible wavelength range, particularly in the infrared range.

[0007] Therefore, the optical sensor must have suitable adjustment means. For example, a display unit can be assigned to at least one receiver or an array of alignment receivers. The display unit then shows the light quantity of the light beams from a transmitter, which is registered at the receiver or the alignment receivers. Based on the light quantity displayed on the display unit, a user can adjust the optical sensor.

[0008] The disadvantage here is that the sensor units must be roughly aligned in advance so that light rays from a transmitter can actually hit the receiver or the alignment receivers and so that the light quantity can be displayed on the display unit.

[0009] Since the light beams of the optical sensor are invisible, this rough alignment is difficult. A user must find a rough alignment of the sensor unit through trial and error, which is cumbersome and time-consuming.

[0010] The invention is based on the object of enabling a simple and reliable adjustment of an optical sensor of the type mentioned above.

[0011] To achieve this object, the features of the independent claims are provided. Advantageous embodiments and expedient developments of the invention are described in the dependent claims.

[0012] The invention relates to an optical sensor with at least one transmitter emitting light beams, at least one receiver receiving light beams, and an evaluation unit designed to evaluate received signals from the at least one receiver. The optical sensor has two sensor units arranged at a distance from one another, with the light beams extending between the sensor units. A mechanical alignment structure is provided on at least one side wall of at least one sensor unit, forming a target geometry that can be targeted and extends in the direction of an optical axis of this sensor unit.

[0013] The invention also relates to a corresponding method.

[0014] The mechanical alignment structure present on at least one side wall of a sensor unit enables simple and at the same time efficient alignment of the sensor units of the optical sensor to one another, in particular in the case that the transmitter(s) of the optical sensor emit light barriers in the non-visible wavelength range, in particular in the infrared range.

[0015] A key advantage is that no optoelectronic or electronic components are required to create an alignment unit. Instead, only an alignment structure is required as a purely mechanical element for alignment, which is present, in particular, attached, to a side wall of a sensor unit. The resulting mechanical alignment structure has a simple, robust, and cost-effective design.

[0016] The functional principle of the mechanical alignment structure according to the invention is such that it forms a target geometry that runs in the direction of an optical axis of the sensor unit. To adjust the optical sensor, the optical axis of the sensor unit must be aligned with the opposite sensor unit to ensure the functionality of the optical sensor. Since the mechanical alignment structure runs in the direction of the optical axis of the sensor unit, advantageously parallel to it, the target geometry provides a direct measure for the orientation of the optical axis. The function is such that a user sights the target geometry, i.e., holds an eye in front of the target geometry. Using the target geometry, the user can sight the opposite sensor units, i.e.,the target geometry is preferably aligned to a fixed point of the opposite sensor unit, whereby the sensor units can be easily aligned to one another.

[0017] According to a particularly advantageous embodiment, at least one mechanical alignment structure is present on each sensor unit.

[0018] An advantage of this embodiment is that each sensor unit can be aligned with the other sensor unit by using its mechanical alignment structure.

[0019] A further advantage of this embodiment is that each sensor unit can be aligned to the target geometry of the other sensor unit by using this target geometry. This means that the target geometry of the other sensor unit forms a target that can be targeted by the target geometry of the mechanical alignment structure of the first sensor unit. This provides a defined reference point for alignment.

[0020] According to an advantageous embodiment, each sensor unit has a front side over which the light beams are guided. The or each mechanical alignment structure is provided on a side wall of a sensor unit adjacent to the front side.

[0021] In this case, a mechanical alignment structure can be particularly advantageously mounted on the top of the sensor unit. Alternatively or additionally, a mechanical alignment structure can be arranged on the side of the sensor unit. Depending on the placement of the mechanical alignment structure, a target on the opposite sensor unit can be aimed at in different directions. By combining several mechanical alignment structures on a sensor unit, alignment in different directions can be achieved.

[0022] The terms top and bottom are defined with reference to the sensor components arranged in the sensor unit and, where applicable, refer to fastening means with which the sensor unit can be mounted to a base, wall or the like.

[0023] Advantageously, the or each side wall of a sensor unit on which the mechanical alignment structure is present forms a flat surface.

[0024] The target geometry can be easily positioned on the flat surface.

[0025] According to a first variant, the optical sensor comprises a first sensor unit in which at least one transmitter emitting light rays is present, and a second sensor unit in which a receiver receiving light rays is present.

[0026] Each sensor unit expediently has a housing, wherein a mechanical alignment structure is present on at least one side wall of at least one housing.

[0027] This optical sensor can be used to detect objects in a monitored area, operating according to the light barrier principle. The sensor units are then located at opposite edges of the monitored area. The evaluation unit then advantageously generates a binary switching signal as an object detection signal, the switching states of which indicate whether or not an object is present in the monitored area.

[0028] This optical sensor can be designed as a light barrier, in which case it only has a transmitter and a receiver. Furthermore, this optical sensor can also be designed as a light curtain. In this case, the first sensor unit contains a series of transmitters emitting light beams. The second sensor unit accordingly contains a series of receivers and the evaluation unit.

[0029] In general, this type of sensor detects objects by interrupting the path of light rays.

[0030] Alternatively, the optical sensor can also function as a data barrier. The transmitter of the data barrier then sends light beams containing encoded data to the associated receiver. The data is decoded in the evaluation unit by evaluating the received signals.

[0031] According to a second variant, the optical sensor comprises a first sensor unit containing at least one transmitter emitting light beams and at least one receiver receiving light beams. A second sensor unit is formed by a reflector.

[0032] The first sensor unit expediently comprises a housing, wherein a mechanical alignment structure is provided on at least one side wall of the housing. Alternatively or additionally, a mechanical alignment structure is provided on a frame of the reflector.

[0033] This optical sensor can also be used to detect objects in a monitored area. In this case, the optical sensor operates according to the reflective light barrier principle. In this case, too, the sensor units are located at opposite edges of the monitored area.

[0034] In the evaluation unit, an object detection signal is again generated in the form of a binary switching signal whose switching states indicate whether an object is in the monitoring area or not.

[0035] The optical sensor can be designed as a retro-reflective light barrier, in which case it has only one transmitter and one receiver. The optical sensor can also be designed as a retro-reflective light curtain with multiple transmitter-receiver pairs.

[0036] Alternatively, this sensor type can also be designed as a distance sensor, in which case distance measurements are performed against the reflector. The distance measurements can be performed, for example, using a pulse-time-of-flight method or a phase measurement method.

[0037] Advantageously, the optical axis of a sensor unit, in the direction of which the target geometry of a mechanical alignment structure runs, is formed by an optical axis of a transmitter or receiver.

[0038] In an optical sensor having a reflector, the optical axis of a sensor unit, in the direction of which the target geometry of a mechanical alignment structure runs, is formed by the optical axis of the reflector.

[0039] The reflector has a flat reflector surface, with the normal vector of the reflector surface forming the optical axis of the reflector.

[0040] According to an advantageous embodiment, the target geometry is formed by a notch and / or edge structure.

[0041] The notch and edge structure runs along a line that runs in the direction of an optical axis, specifically parallel to this optical axis. This structure geometrically clearly defines a target geometry that can be easily recognized and aimed at by a user.

[0042] According to a first variant, the target geometry is formed by a continuous notch or edge structure running in the direction of the optical axis.

[0043] The target geometry then forms a continuous line structure.

[0044] According to a second variant, the target geometry has several discrete target geometry elements arranged one behind the other in the direction of the optical axis, which have a notch or edge structure.

[0045] The target geometry elements then form a broken line structure. Aiming at such a target geometry is done according to the front sight and rear sight principle.

[0046] In both cases, the target geometry of a mechanical alignment structure extends over most of the extent of the side wall of the sensor unit in the direction of the optical axis.

[0047] A large part means that the target geometry extends at least over 30% of the dimension of the sensor unit in the direction of the optical axis.

[0048] Advantageously, a rough alignment of the sensor unit of the optical sensor is carried out by means of the or each mechanical alignment structure.

[0049] The sensor unit can then be fine-tuned, which requires suitable adjustment means. For example, a display unit can be provided in the sensor unit in which the receiver(s) are integrated. The evaluation unit records and evaluates the light quantities of the transmitter light beams that hit the receiver(s). Based on the recorded light quantities, the alignment quality during the adjustment of the sensor unit is determined over time and visualized on the display unit, allowing the user to monitor the status of the adjustment.

[0050] It is also possible to provide alignment receivers directly adjacent to the receiver(s), whereby the alignment quality is determined based on the amount of light from the light beams of the transmitters or other auxiliary transmitters that strike the alignment receiver(s).

[0051] The invention is explained below with reference to the drawings. They show: Figures 1a-b: First embodiment of the optical sensor according to the invention during two alignment processes. Figures 2a-b: Second embodiment of the optical sensor according to the invention during two alignment processes. Figure 3: First embodiment of a mechanical alignment structure with a target geometry. Figures 4a-c: Cross-sectional views of different mechanical alignment structures according to Figur 3. Figure 5: Second embodiment of a mechanical alignment structure with a target geometry. Figure 6a-d: Cross-sectional views of target geometry channels of the mechanical alignment structures according to Figur 4 .

[0052] The Figuren 1a, 1b show a first embodiment of the optical sensor according to the invention in the form of a light curtain 1. The light curtain 1 serves to detect objects in a monitored area. The light curtain 1 has two sensor units 1a, 1b arranged at opposite edges of the monitored area. Each of the sensor units 1a, 1b has a housing 2a, 2b in which sensor components are located. An exit window 3a, 3b is located in the front side of each housing 2a, 2b facing the monitored area.

[0053] The first sensor unit 1a contains a series of transmitters 5 emitting light beams 4, which are controlled by a transmitter controller (not shown). The transmitters 5 emit light beams 4 in the non-visible wavelength range, particularly in the infrared range. The second sensor unit 1b contains a series of receivers 6 receiving light beams 4. The second sensor unit 1b also contains an evaluation unit (not shown), which controls the operation of the receivers 6 and evaluates the received signals generated in the receivers 6.

[0054] In the present case, four transmitters 5 and four receivers 6 are provided, with each transmitter 5 and an associated receiver 6 forming a transmitter-receiver pair. Of course, a different number of transmitter-receiver pairs can also be provided. In particular, only one transmitter-receiver pair can be provided. The optical transmitter 5 then forms a light barrier. In principle, such a light barrier can also be designed as a data light barrier.

[0055] Advantageously, optical synchronization is carried out via the light beams 4 of a transmitter-receiver pair, whereby the transmitter-receiver pairs are activated cyclically one after the other.

[0056] As the Figuren 1a, 1b As shown, the light beams 4 and thus the optical axes of the transmitters 5 run parallel and spaced from each other. The optical axes of the receivers 6 also run parallel and spaced from each other.

[0057] When the monitoring area is clear, the light beams 4 of all transmitters 5, guided through the exit windows 3a, 3b, 10a of the sensor units 1a, 1b, strike the assigned receiver 6 unhindered. If an object intrudes into the monitoring area, the light beams 4 of at least one transmitter 5 are interrupted. Depending on the received signals from the receivers 6, an object detection signal is generated in the evaluation unit in the form of a binary switching signal, with the switching states of the switching signals indicating whether or not an object is present in the monitoring area.

[0058] In the event that the optical sensor forms a safety sensor that is suitable for use in the field of safety technology, its evaluation unit has a fail-safe structure, for example in the form of two mutually monitoring computer units.

[0059] According to the invention, mechanical alignment structures 7a, 7b are provided on the sensor units 1a, 1b, by means of which an alignment of the sensor units 1a, 1b is enabled. Figuren 1a, 1b As shown in the drawings, a mechanical alignment structure 7a, 7b is present on each sensor unit 1a, 1b. In principle, a mechanical alignment structure 7a, 7b can also be present on only one sensor unit 1a, 1b. In the present case, each mechanical alignment structure 7a, 7b is arranged on the top side of a sensor unit 1a, 1b. Alternatively or additionally, a mechanical alignment structure 7a, 7b can also be provided on a side wall of a sensor unit 1a, 1b.

[0060] The Figuren 2a, 2bshow an embodiment of an optical sensor in the form of a reflective light barrier 8, which is used to detect objects in a monitored area. The reflective light barrier 8 has two sensor units 8a, 8b arranged at opposite edges of the monitored area. The reflective light barrier 8 has a first sensor unit 8a, the sensor components of which are integrated in a housing 9a with an exit window 10a.

[0061] Located in the housing 9a are a transmitter 5 emitting light beams 4, a receiver 6 receiving light beams 4, and an evaluation unit (not shown) that controls the transmitter 5 and receiver 6 and evaluates the received signals to generate an object detection signal, which is again a binary switching signal. The transmitters 5 again emit light beams 4 in the non-visible wavelength range. The optical axes of the transmitter 5 and receiver 6 run parallel to each other.

[0062] The second sensor unit 8b is formed by a reflector. The reflector is mounted in a frame and has a flat reflector surface 11, the normal vector of which forms the optical axis of the reflector.

[0063] When the surveillance area is clear, the light beams 4 of the transmitter 5 are guided through the exit window 10a into the surveillance area, strike the reflector, and are reflected back from there so that they are guided through the exit window 10a to the receiver 6. If an object intrudes into the surveillance area, the beam path of the light beams 4 is interrupted.

[0064] The optical sensor according to the Figuren 2a, 2b can also form a distance sensor. Then, using the light beams 4 of the transmitter 5, a distance measurement is carried out against a reflector or against an object with diffuse reflection properties. The distance measurement can be carried out using a pulse-time-of-flight method or a phase measurement method.

[0065] The optical sensor according to the Figuren 2a, 2b can also be developed as a reflection light curtain in which several transmitter-receiver pairs are arranged in the first sensor unit 1a.

[0066] In accordance with the embodiment according to the Figuren 1a, 1b are also in the design of the Figuren 2a, 2b Mechanical alignment structures 7a, 7b are present on the sensor units 8a, 8b.

[0067] Each mechanical alignment structure 7a, 7b has a target geometry 12. The target geometry 12 runs along a line oriented in the direction of the or an optical axis of the sensor units 1a, 1b, 8a, 8b, in particular parallel to the latter.

[0068] Figur 3 shows a plan view of the mechanical alignment structure 7a, wherein the mechanical alignment structure 7b is preferably designed accordingly. The target geometry 12 according to Figur 3is linear and extends over the entire extent of the sensor units 1a, 1b, 8a, 8b in the direction of their optical axis. The side surfaces of the sensor units 1a, 1b, 8a, 8b, to which a mechanical alignment structure 7a, 7b is attached, advantageously form a flat surface, so that the linear target geometry 12 runs along a straight line.

[0069] In general, it is advantageous if the target geometry 12 of a mechanical alignment structure extends over the majority of the extent of the side wall of the sensor unit 1a, 1b, 8a, 8b running in the direction of the optical axis.

[0070] In this case, the majority advantageously means an extension of the target geometry 12 over at least 30% of the extension of the sensor units 1a, 1b, 8a, 8b.

[0071] The cross-section of the target geometry 12 is advantageously constant along its length. The target geometry 12 advantageously forms a notch or edge structure.

[0072] The Figuren 4a bis 4c show three embodiments of cross sections of the target geometry 12. The cross section according to Figur 4a forms an edge 13. The cross section according to Figur 4b has a projection 14 forming an edge structure. The cross section according to Figur 4c forms a V-shaped notch 15.

[0073] Figur 5shows a top view of a mechanical alignment structure 7a, with a further embodiment of a target geometry 12, consisting of the target geometry elements 16a and 16b. The interrupted target geometry 12 facilitates alignment, since the target geometry elements 16a, 16b and the optical target are to be aligned, and thus a misalignment can be detected and corrected more quickly. This target geometry 12 can also be present in the mechanical alignment structure 7b. Such a target geometry can also be used when, for example, already existing elements are used. These can be, for example, screw heads or other already existing fastening elements or structures.

[0074] The target geometry 12 according to Figur 5 runs along a line that is parallel to the or an optical axis of the associated sensor units 1a, 1b, 8a, 8b.

[0075] In the present case, however, the target geometry 12 does not form a continuous linear structure. In this case, the target geometry 12 consists of two discrete target geometry elements 16a, 16b arranged along a straight line running parallel to the optical axis. In this case, it is also advantageous if the target geometry elements 16a, 16b extend over the majority of the extent of the side wall of the sensor unit 1a, 1b, 8a, 8b running in the direction of the optical axis. "Majority" advantageously means an extent of the target geometry over at least 30% of the extent of the sensor units 1a, 1b, 8a, 8b.

[0076] The cross sections of the target geometry elements 16a, 16b in the longitudinal direction of the target geometry 12 are again constant. Figuren 6a, 6b show two embodiments of cross sections of target geometry elements 16a, each forming an edge 13, 13'. Figuren 6c, 6dshow two embodiments of cross sections of target geometry elements 16b forming a notch 15 or a projection 14.

[0077] The functionality of the alignment of the sensor units 1b, the light curtain 1 is explained by the Figuren 1a, 1b explained, whereby the same applies to the reflection light barrier 8 according to the Figuren 2a, 2b applies.

[0078] As in Figur 1a As illustrated, a user uses the mechanical alignment structure 7a to align the sensor unit 1a with the opposite sensor unit 1b. The user sights the target geometry 12 of the mechanical alignment structure (indicated by the dashed line) and thus aims at a target point of the opposite sensor unit 1b, wherein the target geometry 12 of the mechanical alignment structure 7b of the sensor unit 1b is advantageously used as the target point.

[0079] The user adjusts the sensor unit 1a until the target geometry 12 of the mechanical alignment structure 7a is precisely aligned with a target point on the opposite sensor unit 1b. Since the target geometry 12 of the mechanical alignment structure 7a runs in the direction of the optical axes of the transmitters 5, this alignment aligns the optical axes with the target point of the opposite sensor unit 1b.

[0080] Accordingly, a user can align the sensor unit 1b to the sensor unit 1a using the target geometry 12 of the mechanical alignment structure 7a ( Figur 1b ).

[0081] In the design of the Figur 3 the target geometry 12 forms a continuous line that is targeted by the user.

[0082] In the design of the Figur 5 The user aims at both target geometry channels according to the front sight principle. List of reference symbols

[0083] (1)Light curtain (1a)Sensor unit (1b)Sensor unit (2a)Housing (2b)Housing (3a)Exit window (3b)Exit window (4)Light beam (5)Transmitter (6)Receiver (7a)Mechanical alignment structure (7b)Mechanical alignment structure (8)Retro-reflective light barrier (8a)Sensor unit (8b)Sensor unit (9a)Housing (10a)Exit window (11)Reflector surface (12)Target geometry (13)Edge (13')Edge (14)Protrusion (15)Notch (16a)Target geometry element (16b)Target geometry element

Claims

1. Optical sensor with at least one transmitter (5) emitting light beams (4), at least one receiver (6) receiving light beams (4) and an evaluation unit which is designed to evaluate received signals from the at least one receiver (6), and with two sensor units (1a, 1b, 8a, 8b) arranged opposite one another at a distance, wherein the light beams (4) run between the sensor units (1a, 1b, 8a, 8b), characterized in that on at least one side wall of at least one sensor unit (1a, 1b, 8a, 8b) there is a mechanical alignment structure (7a, 7b) which forms a targetable target geometry (12) running in the direction of an optical axis of this sensor unit (1a, 1b, 8a, 8b).

2. Optical sensor according to claim 1, characterized in that at least one mechanical alignment structure (7a, 7b) is present on each sensor unit (1a, 1b, 8a, 8b).

3. Optical sensor according to one of claims 1 or 2, characterized in thateach sensor unit (1a, 1b, 8a, 8b) has a front side over which the light beams (4) are guided, and that the or each mechanical alignment structure (7a, 7b) is present on a side wall of a sensor unit (1a, 1b, 8a, 8b) adjacent to the front side.

4. Optical sensor according to one of claims 1 to 3, characterized in that the or each side wall of a sensor unit (1a, 1b, 8a, 8b) on which the mechanical alignment structure (7a, 7b) is present forms a flat surface.

5. Optical sensor according to one of claims 1 to 4, characterized in that this has a first sensor unit (1a) in which at least one transmitter (5) emitting light rays (4) is present, and a second sensor unit (1b) in which a receiver (6) receiving light rays (4) is present.

6. Optical sensor according to claim 5, characterized in thateach sensor unit (1a, 1b, 8a, 8b) has a housing (2a, 2b, 9a), wherein a mechanical alignment structure (7a, 7b) is present on at least one side wall of at least one housing (2a, 2b, 9a).

7. Optical sensor according to one of claims 1 to 4, characterized in that this has a first sensor unit (8a) in which at least one transmitter (5) emitting light rays (4) and at least one receiver (6) receiving light rays (4) are present, and that a second sensor unit (8b) is formed by a reflector.

8. Optical sensor according to claim 7, characterized in that the first sensor unit (1a) has a housing (9a), wherein a mechanical alignment structure (7a) is provided on at least one side wall of the housing (9a), and / or that a mechanical alignment structure (7b) is provided on a frame of the reflector.

9. Optical sensor according to one of claims 1 to 8, characterized in thatthe optical axis of a sensor unit (1a, 1b, 8a), in the direction of which the target geometry (12) of a mechanical alignment structure runs, is formed by an optical axis of a transmitter (5) or receiver (6).

10. Optical sensor according to claim 7, characterized in that the optical axis of a sensor unit (8b), in the direction of which the target geometry (12) of a mechanical alignment structure runs, is formed by the optical axis of the reflector.

11. Optical sensor according to claim 10, characterized in that the reflector has a flat reflector surface (11), wherein the normal vector of the reflector surface (11) forms the optical axis of the reflector.

12. Optical sensor according to one of claims 1 to 11, characterized in that the target geometry (12) is formed by a notch and / or edge structure.

13. Optical sensor according to claim 12, characterized in thatthe target geometry (12) is formed by a continuous notch or edge structure running in the direction of the optical axis.

14. Optical sensor according to claim 12, characterized in that the target geometry (12) has a plurality of discrete target geometry elements (16a, 16b) arranged one behind the other in the direction of the optical axis, which have a notch or edge structure.

15. Optical sensor according to claim 14, characterized in that discrete target geometry elements (16a, 16b) are formed from housing or fastening elements.

16. Optical sensor according to one of claims 1 to 15, characterized in that the target geometry (12) of a mechanical alignment structure extends over the majority of the extent of the side wall of the sensor unit (1a, 1b, 8a, 8b) running in the direction of the optical axis.

17. Optical sensor according to one of claims 1 to 16, characterized in thatthe transmitter(s) (5) emit light beams (4) in the non-visible wavelength range.

18. Optical sensor according to one of claims 1 to 17, characterized in that a rough alignment of the sensor units (1a, 1b, 8a, 8b) is carried out by means of the mechanical alignment structure (7a, 7b), and that means for fine adjustment of the sensor units (1a, 1b, 8a, 8b) are provided.

19. Optical sensor according to one of claims 1 to 18, characterized in that which is designed to detect objects in a surveillance area, wherein the sensor units (1a, 1b, 8a, 8b) are arranged at opposite edges of the surveillance area.

20. Optical sensor according to claim 18, characterized in that Objects are detected by interrupting the path of light rays (4).

21. Optical sensor according to one of claims 7 to 18, characterized in that This forms a distance sensor.

22. Optical sensor according to one of claims 5 to 18, characterized in that This forms a data light barrier.

23. Method for operating an optical sensor with at least one transmitter (5) emitting light beams (4), at least one receiver (6) receiving light beams (4) and an evaluation unit which is designed to evaluate received signals from the at least one receiver (6), and with two sensor units (1a, 1b, 8a, 8b) arranged opposite one another at a distance, wherein the light beams (4) run between the sensor units (1a, 1b, 8a, 8b), characterized in that on at least one side wall of at least one sensor unit (1a, 1b, 8a, 8b) there is a mechanical alignment structure (7a, 7b) which forms a targetable target geometry (12) running in the direction of an optical axis of this sensor unit (1a, 1b, 8a, 8b).