Optical Sensors

Abstract

The optical sensor (1) of the present invention detects the approach of an object (5) based on the result of light reception. The optical sensor includes a light source (21), a light receiving part (22) and a convex part (13). The light source emits light (L1) toward the object. The light receiving part receives reflected light (L2) of the emitted light reflected by the object and generates a signal indicating the result of light reception. The convex part has a height higher than that of the light source and the light receiving part. The convex part is arranged between the light source and the light receiving part so that the reflected light from the light source is blocked from the light receiving part when it is reflected within a range of a given distance (D1) from the convex part. The light receiving part outputs a signal corresponding to the approach of an object within the range of the given distance, so as to indicate the result of light reception below a threshold light amount indicating that the reflected light is not received.

Description

Technical Field

[0001] The present invention relates to an optical sensor for optically detecting the proximity of an object. Background Art

[0002] In recent years, various sensors have been proposed that are mounted on robot hands or the like and that can perform various sensing such as approach or contact of an object (for example, Patent Documents 1 to 3).

[0003] Patent document 1 discloses a system for measuring the contact force caused by an object and the distance to the object when a robot is holding an object, etc. In the system of patent document 1, the force, distance and contact are measured by using the signal of an infrared proximity sensor embedded in an elastic body that is transparent to infrared light.

[0004] Patent document 2 discloses an optical tactile sensor capable of measuring 6-axis forces. Patent document 3 discloses a force sensor that uses a variable frame to detect shear force. In Patent documents 2 and 3, various contact forces caused by an object are sensed in an optical mechanism that uses deformation of an elastic body.

[0005] Prior Art Literature

[0006] Patent Literature

[0007] Patent Document 1: U.S. Patent Application Publication No. 2017 / 0297206

[0008] Patent Document 2: Japanese Patent No. 5825604

[0009] Patent Document 3: International Publication No. 2014 / 045685 Summary of the invention

[0010] Problem that the invention aims to solve

[0011] In the prior art such as Patent Document 1, the amount of reflected infrared light from an object is used as a signal of an infrared proximity sensor. However, the amount of reflected light varies depending on the reflectivity of the object, and the absolute value of the amount of reflected light in a state of contact varies. Therefore, it is difficult to separately sense whether the amount of light changes with approach or whether the object is pushed into the sensor in a state of contact.

[0012] An object of the present invention is to provide an optical sensor capable of detecting the approach of an object to a specific distance regardless of the reflectivity of the object.

[0013] Means used to solve problems

[0014] The optical sensor to which the present invention relates detects the approach of an object based on the result of light reception. The optical sensor includes a light source, a light receiving portion, and a convex portion. The light source emits light toward an object. The light receiving portion receives reflected light of the emitted light reflected from the object, and generates a signal indicating the result of light reception. The convex portion has a height higher than that of the light source and the light receiving portion. The convex portion is arranged between the light source and the light receiving portion so that the reflected light when the light from the light source is reflected within a range of a given distance from the convex portion is shielded from the light receiving portion. The light receiving portion outputs a signal corresponding to the approach of an object within the range of a given distance, so as to indicate a light reception result below a threshold light amount indicating that the reflected light is not received. In addition, the threshold light amount that can be regarded as the reflected light not being received is pre-set to be less than 10% of the light output power output from the light source.

[0015] Effects of the Invention

[0016] According to the optical sensor of the present invention, it is possible to detect with high accuracy that an object has approached a specific distance regardless of the reflectivity of the object. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a diagram for explaining the outline of the optical sensor involved in Embodiment 1.

[0018] Figure 2 This is a top view of the optical sensor involved in embodiment 1.

[0019] Figure 3 This is a block diagram showing the structure of the optical sensor involved in Embodiment 1.

[0020] Figure 4 is a diagram illustrating a threshold distance in an optical sensor.

[0021] Figure 5 This is a diagram for explaining an overview of the operation of the optical sensor.

[0022] Figure 6 This is a timing diagram illustrating the operation of the optical sensor.

[0023] Figure 7 This is a diagram for explaining an environment for numerical simulation of an optical sensor.

[0024] Figure 8 2 is a diagram showing the results of numerical simulations on the optical sensor.

[0025] Fig. 9 This is a block diagram showing the structure of an optical sensor according to the second embodiment.

[0026] Fig.10 This is a flowchart illustrating the operation of the optical sensor involved in the second embodiment.

[0027] Fig.11 It is shown Fig.10 Flowchart of an example of the processing of step S4.

[0028] Fig.12 This is a block diagram showing the structure of an optical sensor involved in Embodiment 3.

[0029] Fig.13 This is a diagram for explaining the force sensor portion of the optical sensor in the third embodiment.

[0030] Fig.14 This is a plan view showing an example of an optical sensor according to Embodiment 3.

[0031] Fig.15 yes Fig.14 A cross-sectional view of an illustrated optical sensor.

[0032] Fig.16 This is a top view of an optical sensor according to a modified example of the first embodiment.

[0033] Fig.17 FIG. 1 is a diagram showing a modified example of the threshold distance in the optical sensor. DETAILED DESCRIPTION

[0034] Hereinafter, embodiments of an optical sensor according to the present invention will be described with reference to the drawings.

[0035] Each embodiment is for illustration, and it is self-evident that partial replacement or combination of the structures shown in different embodiments can be performed. After the second embodiment, the description of matters common to the first embodiment is omitted, and only the differences are described. In particular, the same effects brought about by the same structure will not be mentioned one by one in each embodiment.

[0036] (Implementation Method 1)

[0037] 1. Structure

[0038] Reference Figure 1 The structure of the optical sensor according to Embodiment 1 will be described. Figure 1 It is a diagram for explaining the outline of the optical sensor 1 according to the present embodiment.

[0039] The optical sensor 1 of this embodiment is a module that integrally constitutes a proximity sensor unit 12 and a force sensor unit 13. The proximity sensor unit 12 detects the approach of the object 5 in an optical detection manner, and the force sensor unit 13 detects the force (i.e., contact force) applied when the object 5 contacts. The optical sensor 1 can be used, for example, to detect various objects held by a robot hand as the object 5. The optical sensor 1 can continuously detect a series of processes such as the object 5 approaching, contacting, and applying force, etc. through the proximity sensor unit 12 and the force sensor unit 13.

[0040] In the optical sensor 1, the proximity sensor unit 12 includes a light source 21 that emits a detection light L1 for detecting the approach of the object 5, and a light receiving unit 22 that receives light incident from the outside. According to the proximity sensor unit 12, the light receiving unit 22 receives the reflected light L2 reflected by the detection light L1 from the object 5, thereby detecting the approach of the object 5.

[0041] In a general optical proximity detection method, even when various objects 5 approach to the same distance, the amount of reflected light L2 changes depending on the reflectivity of each object 5, so there is a problem that it is difficult to detect the distance to which the object 5 approaches. In contrast, in this embodiment, an optical sensor 1 is provided that can detect that an object 5 approaches a specific distance regardless of the reflectivity of the object 5.

[0042] 1-1. Details of the structure

[0043] Hereinafter, the structure of the optical sensor 1 according to the present embodiment will be described in detail.

[0044] Figure 2 1 is a top view of an optical sensor 1 according to the present embodiment. The optical sensor 1 is configured by assembling a proximity sensor unit 12 and a force sensor unit 13 on a substrate 11. Hereinafter, two directions parallel to the main surface of the substrate 11 are respectively referred to as the X direction and the Y direction, and the normal direction of the main surface is referred to as the Z direction.

[0045] In the optical sensor 1 of the present embodiment, the light source 21 and the light receiving unit 22 of the proximity sensor unit 12 are arranged on the substrate 11 so as to sandwich the force sensor unit 13, for example, in the X direction. Hereinafter, the +Z side where the force sensor unit 13 protrudes from the substrate 11 is sometimes referred to as the upper side, and the -Z side which is the opposite side is sometimes referred to as the lower side. Details of the arrangement of the proximity sensor unit 12 and the force sensor unit 13 in the optical sensor 1 will be described later.

[0046] Figure 31 is a block diagram showing the structure of the optical sensor 1 according to the present embodiment. The optical sensor 1 according to the present embodiment includes a proximity detection unit 2 including a proximity sensor unit 12, a light source driving circuit 23, and a proximity detection circuit 24, and a force detection unit 3 including a force sensor unit 13 and a force detection circuit 30.

[0047] In the proximity detection unit 2, the light source 21 includes a light-emitting element such as a VCSEL (surface emitting laser) having a single or multiple emitters, and has narrow directivity. For example, the light source 21 emits light having a given wavelength band such as an infrared region, and has a light emitting surface 21a emitted as the detection light L1. The light source 21 is configured so that the light emitting surface 21a faces upward.

[0048] The light source 21 is not limited to VCSEL, and may include various solid light emitting elements such as LD (semiconductor laser) or LED. The light source 21 may also include a plurality of light emitting elements. The light source 21 may also be provided with an optical system such as a lens and a reflector that collimates the light from the light emitting element.

[0049] The light receiving unit 22 includes one or more light receiving elements such as PD (photodiode) and has a light receiving surface 22a formed by the light receiving elements. The light receiving unit 22 receives light such as reflected light L2 of the probe light L1 on the light receiving surface 22a and generates a light receiving signal indicating the amount of light received as a result of the light receiving.

[0050] The light receiving unit 22 is not limited to PD, and may also include various light receiving elements such as phototransistors, PSDs (position detection elements), CISs (CMOS image sensors) or CCDs. The light receiving unit 22 may also be composed of a linear array or a two-dimensional array of light receiving elements. The light receiving unit 22 may also be provided with an optical system such as a lens for focusing the reflected light L2. In addition, a bandpass filter or the like that blocks light of a band different from the band of the detection light L1 may also be provided on the light receiving surface 22a of the light receiving unit 22. In this way, the influence of interfering light caused by the external environment can be suppressed.

[0051] The light source driving circuit 23 supplies a driving signal for emitting the detection light L1 to the light source 21. The light source driving circuit 23 may also include a modulator such as AM modulation. For example, the light source driving circuit 23 may also modulate the detection light L1 using a modulation frequency such as 10 Hz to 1 MHz to periodically change the amplitude of the light. By modulating the detection light L1, it becomes easy to distinguish the detection light L1 and its reflected light L2 from the interference light.

[0052] The proximity detection circuit 24 performs various signal processing on the light receiving signal output from the light receiving unit 22 to generate a proximity detection signal. The signal processing includes, for example, various calculation processing for estimating the distance to the object 5 and its changes based on the amount of light of the light receiving result, and may also include processing for extracting the amount of light of the reflected light L2 from the light receiving result. The proximity detection signal can be set to various signals showing the detection result of the proximity of the object 5 in accordance with various signal processing. In addition, the proximity detection circuit 24 may also include a circuit structure for driving the light receiving unit 22, and may also include a sensor amplifier for amplifying the signal output from the light receiving element. Such a circuit structure may also be included in the light receiving unit 22 together with the light receiving element.

[0053] The proximity detection circuit 24 may also perform filter processing such as a bandpass filter that allows a signal component containing the modulation frequency of the detection light L1 to pass through, and may also perform synchronous detection in synchronization with the light source driving circuit 23. For example, in the proximity detection circuit 24, by blocking the steady-state DC component, the reflected light L2 can be analyzed separately from the interfering light. The modulation frequency of the detection light L1 can be appropriately set to avoid frequencies used in existing external systems, such as 38kHz used as a carrier of an infrared remote controller. As a result, malfunctions of the optical sensor 1 caused by the external system can be suppressed.

[0054] In the force detection unit 3 of this embodiment, various force detection methods can be used to detect the force from the object 5. Various force detection methods include, for example, piezoelectric, optical, strain resistance, and electrostatic capacitance. The force detection unit 3 detects force in multiple axes such as three axes or six axes.

[0055] The force sensor portion 13 constitutes a portion that the object 5 contacts when detecting the force from the object 5 in the adopted force detection method. The force sensor portion 13 includes a sensor element and its package in the force detection method. For example, the force sensor portion 13 has a truncated cone shape and contacts the object 5 at the upper surface 13a. The shape of the force sensor portion 13 is not particularly limited, and various convex shapes may be used. The force sensor portion 13 is an example of a convex portion in the optical sensor 1 of the present embodiment.

[0056] The force detection circuit 30 generates a force detection signal indicating the detection result of the force in multiple axes, for example, based on the signal output from the sensor element in the force sensor unit 13. The force detection circuit 30 is not limited to multiple axes, and may output a force detection signal indicating the detection result of the force in one axis. The force detection circuit 30 may also include a circuit structure for driving the sensor element, and may also include a sensor amplifier for amplifying the signal output from the sensor element.

[0057] The above-described structure is an example, and the optical sensor 1 is not particularly limited to the above-described structure. For example, the optical sensor 1 of this embodiment may also have any of the circuits 23, 24, and 30 as an external structure, or may be provided as a module separate from the circuits 23, 24, and 30.

[0058] 1-2. Configuration of proximity sensor and force sensor

[0059] use Figure 4 The details of the arrangement of the proximity sensor unit 12 and the force sensor unit 13 in the optical sensor 1 will be described.

[0060] Figure 4 2 is a diagram illustrating a threshold distance D1 in the optical sensor 1. In the present embodiment, the light source 21, the light receiving unit 22 (proximity sensor unit 12), and the force sensor unit 13 are configured so that the optical sensor 1 has a threshold distance D1. The threshold distance D1 is a distance at which the reflected light L2 of the detection light L1 emitted from the light source 21 is blocked by the force sensor unit 13 and the reflected light L2 incident on the light receiving surface 22a of the light receiving unit 22 becomes a boundary below the set threshold light amount. The threshold light amount indicates the light amount that can be regarded as a reference for the reflected light L2 not being received. In addition, the threshold light amount is pre-set to, for example, 10% or less of the light output power output from the light source 21.

[0061] Figure 4 Corresponds to a side view of the optical sensor 1 as viewed from the Y direction. In the present embodiment, the force sensor portion 13 has an upper surface 13a that protrudes upward by a height H1 more than the light emitting surface 21a of the light source 21 and the light receiving surface 22a of the light receiving portion 22. In other words, the light source 21 and the light receiving portion 22 are disposed at a position lower than the upper surface 13a of the force sensor portion 13. Furthermore, the force sensor portion 13 is disposed between the light source 21 and the light receiving portion 22 of the proximity sensor portion 12, and the light source 21 is smaller than the force sensor portion 13. In addition, the light source 21 is disposed so that the distance from the force sensor portion 13, i.e., the interval W1, becomes a distance shorter than the height H1 of the force sensor portion 13. By such an arrangement, it is possible to generate a phenomenon in which the force sensor portion 13 blocks the reception of the reflected light L2 according to the distance between the object 5 and the optical sensor 1.

[0062] exist Figure 4 , the optical paths of the detection light L1 and the reflected light L2 when the object 5 is at the threshold distance D1 are illustrated. The distance between the object 5 and the optical sensor 1 can be defined along the Z direction with reference to the upper surface 13a of the force sensor unit 13.

[0063] exist Figure 4In the example, the probe light L1 travels upward from the light source 21 along the Z direction by a threshold distance D1, and is reflected at the reflection position P1 at the distance D1. In the optical path of the reflected light L2 from the reflection position P1, the optical path that is straight toward the light receiving unit 22 overlaps with the force sensor unit 13 halfway. Therefore, the component of the reflected light L2 that travels in the optical path is incident on the force sensor unit 13 and is blocked. On the other hand, the component of the reflected light L2 that travels in the optical path that does not overlap with the force sensor unit 13 deviates from the light receiving unit 22 and travels without reaching the light receiving surface 22a.

[0064] As described above, the reflected light L2 from the reflection position P1 at the threshold distance D1 is blocked by the force sensor unit 13 and is not received by the light receiving unit 22. In addition, the reflected light L2 from the reflection position closer to the optical sensor 1 than the threshold distance D1 is also not received by the light receiving unit 22 in the same manner as described above. On the other hand, the reflected light L2 from the reflection position farther than the threshold distance D1 has an optical path toward the light receiving unit 22 without overlapping with the force sensor unit 13, and can reach the light receiving surface 22a.

[0065] In the present embodiment, the threshold distance D1 as described above can be preset to a desired size corresponding to various specifications of the optical sensor 1 by, for example, adjusting the size and layout parameters when manufacturing the optical sensor 1. The threshold distance D1 is an example of a given distance in the optical sensor 1 of the present embodiment.

[0066] Parameters that can adjust the threshold distance D1 include, for example, the distance W1 between the light source 21 and the force sensor unit 13 and the distance W2 between the light receiving unit 22 and the force sensor unit 13. Figure 4 In the example, the larger the interval W1 is, the larger the threshold distance D1 can be. On the other hand, the smaller the interval W2 is, the larger the threshold distance D1 can be. In addition, the parameters of the threshold distance D1 are not limited to the intervals W1 and W2, and may include, for example, the dimensions and shapes such as the height H1 of the force sensor unit 13, the dimensions and shapes such as the height of the light source 21, and the dimensions and shapes such as the height of the light receiving unit 22.

[0067] Furthermore, according to the optical sensor 1 as described above, the light source 21 and the light receiving unit 22 are located at a position lower than the upper surface 13a of the force sensor unit 13, so that it is easy to avoid a situation where the object 5 contacts the light source 21 and the light receiving unit 22 and is damaged. Furthermore, with the above-described structure, a small and low-cost optical sensor 1 can be provided.

[0068] 2. Action

[0069] The operation of the optical sensor 1 configured as above will be described below.

[0070] 2-1. Overview of the operation

[0071] use Figure 5 An outline of the operation of the optical sensor 1 according to the present embodiment will be described.

[0072] In the optical sensor 1 of this embodiment, the light source driving circuit 23 drives the light source 21 by a driving signal to emit the probe light L1. The light source 21 emits the probe light L1 upward, for example, along the Z direction. When the probe light L1 is incident on the object 5, it is reflected, for example, diffusely, according to the reflectivity of the object 5.

[0073] Figure 5 (A) illustrates a state where the object 5 is separated from the optical sensor 1 by a distance D. Figure 5 (B) exemplifies the object 5 from Figure 5 The state (A) is close to and in contact with the optical sensor 1. Figure 5 In the state illustrated in (A), the distance D to the object 5 is greater than the threshold distance D1.

[0074] exist Figure 5 In the example of (A), the reflected light L2 of the detection light L1 at the object 5 is incident on the light receiving unit 22. In the optical sensor 1, the proximity detection circuit 24 generates a proximity detection signal based on the light reception result of the light receiving unit 22. The light amount of the reflected light L2 received by the light receiving unit 22 varies according to the distance D to the object 5, so various operations for estimating the distance to the object 5 based on the light reception signal can be applied to the proximity detection circuit 24.

[0075] In addition, for example Figure 5 As shown in (B) of FIG. 1 , when the object 5 contacts the force sensor unit 13, a force is applied from the object 5 according to the degree of contact. The force detection circuit 30 of the optical sensor 1 detects force in, for example, multiple axes and generates a force detection signal.

[0076] In the optical sensor 1 of this embodiment, Figure 5 The state of (A) reaches Figure 5 During the state (B), if the distance to the object 5 becomes less than the threshold distance D1, the reflected light L2 of the detection light L1 is blocked by the force sensor unit 13 and no longer reaches the light receiving unit 22. By utilizing this phenomenon, the optical sensor 1 of this embodiment can output the information indicating whether the object 5 is close to within the threshold distance D1 in the proximity detection signal according to the light reception result of the light receiving unit 22.

[0077] The detection result of the approach before and after the threshold distance D1 as described above can be obtained with high accuracy without depending on the reflectivity of the object 5. In addition, the threshold distance D1 can be preset to a desired distance. Therefore, the optical sensor 1 of this embodiment can use the threshold distance D1 to continuously detect a series of processes from the approach of the object 5 to the generation of the contact force with good accuracy. The following is a description of the details of the operation of the optical sensor 1.

[0078] 2-2. Action details

[0079] The optical sensor 1 of this embodiment starts operating when the existence of the object 5 is confirmed by the control system of various robots such as a robot hand to which the optical sensor 1 is applied. Figure 6 (A) to (E) illustrate an example of the operation of the optical sensor 1 in such a case.

[0080] Figure 6 (A) is a graph showing an example of a change in the distance between the object 5 and the optical sensor 1 . Figure 6 (B) illustrates the driving signal of the light source 21. Figure 6 (C) illustrates a light receiving signal (as an example of a proximity detection signal) in the light receiving unit 22. Figure 6 (D) illustrates a proximity sign which is an example of a proximity detection signal in the optical sensor 1 . Figure 6 (E) illustrates the force detection signal in the optical sensor 1. Figure 6 The horizontal axes of (A) to (E) represent time.

[0081] exist Figure 6 In (A), the object 5 starts to approach the optical sensor 1 from time t1 and contacts the force sensor unit 13 at time t2 (see Figure 5 In this example, the optical sensor 1 is based on Figure 6 The driving signal exemplified in (B) emits the probe light L1, which is irradiated to the object 5. The reflected light L2 of the probe light L1 at the object 5 is incident on the light receiving unit 22 together with the disturbance light, for example. Figure 6 (C) shows an example of a light receiving signal after interference light is filtered in the optical sensor 1.

[0082] The optical sensor 1 can also Figure 6 The light receiving signal as exemplified in (C) is output to the above-mentioned control system etc. as an example of a proximity detection signal. Figure 6 In the condition (A), the signal level of the light receiving signal gradually increases from time t1 according to the light amount of the reflected light L2 received. By such a change in the light receiving signal, it is possible to detect that the object 5 is approaching.

[0083] exist Figure 6 In the condition (A), at time t20 immediately before time t2 at which the force sensor unit 13 comes into contact, the distance to the object 5 reaches the threshold distance D1. Figure 6 As shown in (C), the light receiving signal decreases rapidly before time t20 and reaches the threshold light amount A1 at time t20. The timing when the object 5 reaches the threshold distance D1, that is, the timing just before contact, can be detected by the signal level of the light receiving signal.

[0084] As a further example of a proximity detection signal, the optical sensor 1 of this embodiment can also be as follows Figure 6 The proximity flag is generated as shown in (D). The proximity flag is a flag indicating whether the object 5 is approaching to a threshold distance D1 or more by "1" or "0". Figure 6 The signal level of the light receiving signal (C) approaches the flag rising from "0" to "1" at time t20.

[0085] In addition, Figure 6 In the example of (A), the object 5 generates various contact forces during the period T11 from time t2 to time t3 when it is in contact with the force sensor unit 13. At this time, the force detection unit 3 of the optical sensor 1 is as follows. Figure 6 As shown in (E), a force detection signal indicating the detection result of the contact force is generated.

[0086] and then, Figure 6 In the example (A), the object 5 leaves the force sensor unit 13 at time t3, and reaches the threshold distance D1 at the subsequent time t31, and moves away from the optical sensor 1. In the optical sensor 1, Figure 6 As shown in (C), the signal level of the light-receiving signal increases sharply at time t31 and exceeds the threshold light amount A1. Figure 6 As shown in (D), the proximity flag returns from "1" to "0" at time t31. In addition, the proximity flag as described above may not be generated in the optical sensor 1, but may be managed in the control system.

[0087] According to the above operation of the optical sensor 1, the force detection signal ( Figure 6 (E)), it is possible to detect the contact force generated during the period T11 from time t2 to time t3 when the object 5 makes contact. In addition, by using the proximity detection signal ( Figure 6(C), (D)), it is possible to detect that the object 5 is near the optical sensor 1 (within the threshold distance D1) during the period T10 from time t20 to time t31 including the period T11. For example, at time t21 when the proximity mark rises, the optical sensor 1 can detect the timing just before contact. By such an operation of the optical sensor 1, for example, it is possible to make it easy to plan when holding the object 5 in the control system.

[0088] For example, by applying the optical sensor 1 to the end effector (i.e., robot hand) of a robot arm such as a multi-fingered hand or a gripper, it is possible to easily grasp an object 5 such as an indeterminate object or a soft object. Generally, when a robot arm is used to grasp an object 5, a visual sensor such as a camera in a robot control system recognizes the object 5, and the robot arm is moved to a position where the object 5 can be grasped. At this time, due to the movable error of a movable part such as a joint of the robot arm or the rigidity of the arm itself, the robot arm may deviate from the target position and fail to perform appropriate movements, resulting in a situation where the indeterminate object or the soft object cannot be grasped. In addition, there may be a situation where the object 5 enters a blind spot of the visual sensor due to the movement of the robot arm, and the position of the object 5 cannot be grasped.

[0089] In contrast, by using the end effector provided with the optical sensor 1 of the present embodiment for a robot arm, even if the robot arm deviates from the target position, it is possible to detect how close the end effector is to the object 5. Therefore, based on the information of the proximity and force detection results generated by the optical sensor 1, it is possible to precisely correct the position of the robot arm and the movement of the end effector, thereby enabling the gripping of indefinite objects and soft objects.

[0090] Furthermore, even if the object 5 enters the blind spot of the visual sensor, the distance to the object 5 can be estimated based on the information of the proximity detection result generated by the optical sensor 1. Furthermore, since the information of the proximity of the object 5 and the force detection result can be obtained from one sensor, it is possible not only to formulate a gripping plan indicating how to grip the object 5 before contacting the object 5, but also to perform gripping feedback control during the gripping of the object 5 so that there will be no failure even if the gripping state changes. Therefore, it is possible to grip an indeterminate object or a soft object efficiently with less failure.

[0091] 2-3. Numerical simulation of threshold distance

[0092] The inventors of the present application have conducted numerical simulations on the threshold distance D1 of the optical sensor 1 described above and confirmed the effect thereof. Figure 7 , 8 Numerical simulation of the threshold distance D1 in the optical sensor 1 will be described.

[0093] Figure 7 It is a diagram for explaining the environment of numerical simulation regarding the optical sensor 1 . Figure 8 It is a figure which shows the result of this simulation.

[0094] In this simulation, the light receiving power corresponding to the amount of light received by the light receiving unit 22 of the reflected light L2 of the probe light L1 was numerically calculated when the distance D to the object 5 was changed at various intervals W1 and W2. Figure 7 As shown, the interval W1 between the light source 21 and the force sensor unit 13 is defined by the distance from the center position of the light source 21 to the end of the force sensor unit 13 in the X direction, and W11, W12, and W13 increase in ascending order. In addition, the interval W2 between the light receiving unit 22 and the force sensor unit 13 is defined by the distance from the center position of the light receiving unit 22 to the end of the force sensor unit 13 in the X direction, and W21, W22, and W23 increase in ascending order.

[0095] In this simulation, the reflectance of the object 5 was changed and the above-mentioned numerical calculations were performed. Figure 8 (A) shows the simulation result when the reflectance of the object 5 is set to 99%. Figure 8 (B) shows the simulation result when the reflectance of the object 5 is set to 14%. Figure 8 The horizontal axis of (A) and (B) shows the distance D in mm. The vertical axis shows the received light power normalized to be greater than or equal to 0 and less than or equal to 1.

[0096] like Figure 8 As shown in (A) and (B) of FIG. 1 , if the reflectivity of the object 5 changes in this simulation, the light receiving power at various distances D changes, while the distance D when the light receiving power reaches "0", that is, the threshold distance D1, does not change. Therefore, through this simulation, it is confirmed that the optical sensor 1 can perform proximity detection at the threshold distance D1 regardless of the reflectivity of the object 5.

[0097] In addition, Figure 8 In the simulation results of (A) and (B), if the interval W1 between the light source 21 and the force sensor unit 13 is reduced from "W13" to "W11", or the interval W2 between the light receiving unit 22 and the force sensor unit 13 is increased from "W21" to "W23", the threshold distance D1 becomes smaller. Therefore, it is also confirmed that the threshold distance D1 can be set to a desired length by adjusting the intervals W1, W2, etc., etc., by arranging the light source 21, the light receiving unit 22, and the force sensor unit 13. With such a layout, for example, the threshold distance D1 can be set to near "0" in consideration of the height H1 of the force sensor unit 13, and the position where the object 5 contacts the force sensor unit 13 can be set as the detection target.

[0098] 3. Summary

[0099] As described above, the optical sensor 1 in this embodiment detects the approach of the target object 5 as various objects based on the result of receiving light. The optical sensor includes a light source 21 as an example of a first light source, a light receiving unit 22 as an example of a first light receiving unit, and a force sensor unit 13 as an example of a convex portion. The light source 21 emits light such as the detection light L1 toward the target object 5. The light receiving unit 22 receives the reflected light L2 reflected by the target object 5 from the emitted detection light L1, and generates a light receiving signal as a signal indicating the result of receiving light. The force sensor unit 13 has a height H1 higher than the light source 21 and the light receiving unit 22. The force sensor unit 13 is arranged between the light source 21 and the light receiving unit 22 so that the reflected light L2 when the detection light L1 from the light source 21 is reflected within a range of a threshold distance D1 (given distance) from the force sensor unit 13 is blocked from the light receiving unit 22. The light receiving unit 22 outputs a proximity detection signal such as a light receiving signal in response to the approach of the object 5 within the range of the threshold distance D1, so as to show a light receiving result below the threshold light amount A1 indicating that the reflected light L2 is not received. In addition, the threshold light amount A1 at which the reflected light L2 is considered not to be received is pre-set to, for example, 10% or less of the light output power output from the light source 21.

[0100] According to the above optical sensor 1, when the approach of the object 5 as various objects is detected based on the light reception result of the reflected light L2 from the object 5, a light reception result of a threshold light amount A1 or less, which can be regarded as the reflected light L2 not being received, is obtained corresponding to the approach of the object 5 within the range of the threshold distance D1. Thus, within the range of the reflectivity of the reflected light L2 from the object 5 that can be received by the light receiving unit 22, it is possible to detect the approach of the object 5 to the threshold distance D1 regardless of the reflectivity of the object 5.

[0101] For example, when the object 5 approaches to within the range of the threshold distance D1, the light receiving unit 22 outputs a light receiving signal to show that the reflected light L2 from the object 5 is not received. In addition, the light receiving unit 22 receives the reflected light L2 that arrives without being blocked by the force sensor unit 13 in response to the approach of the object 5 to the outside of the range of the threshold distance D1. When the object 5 reaches the outside of the range of the threshold distance D1 from the state of being within the range of the threshold distance D1, the light receiving unit 22 outputs a light receiving signal to show that the reflected light L2 starts to be received. By such a light receiving signal, the movement of the object 5 before and after approaching the threshold distance D1 can be easily detected. Such proximity detection can be achieved by configuring the force sensor unit 13, the light source 21, and the light receiving unit 22 so that at least a part of the reflected light L2 when the light from the light source 21 is reflected outside the range of the threshold distance D1 is not blocked from the light receiving unit 22.

[0102] In this embodiment, the force sensor portion 13 as a convex portion constitutes the force detection portion 3 that detects the force generated by the contact of the object 5. According to such an optical sensor 1, a series of processes in which the object 5 approaches, contacts, and generates force can be continuously detected.

[0103] (Implementation Method 2)

[0104] In implementation mode 2, using Figures 9-11 An example in which the detection result of the proximity at the threshold distance D1 is effectively used for the power control of the force detection unit 3 will be described.

[0105] Fig. 9 This is a block diagram showing the structure of an optical sensor 1A according to Embodiment 2. The optical sensor 1A of this embodiment has the same structure as Embodiment 1 (see Figure 3 ) is provided with a control unit 10 for further controlling the actions of the force detection unit 3 and the proximity detection unit 2.

[0106] The control unit 10 is composed of, for example, a microcomputer, and cooperates with software to realize a given function. The control unit 10 has, for example, an internal memory such as a ROM and a RAM, and reads the data and programs stored in the ROM into the RAM to perform various calculations and realize various functions. In addition, the control unit 10 may also be a hardware circuit such as a dedicated electronic circuit or a reconfigurable electronic circuit designed to realize a given function. The control unit 10 may also be composed of various semiconductor integrated circuits such as a CPU, an MPU, a DSP, an FPGA, and an ASIC.

[0107] For example, the control unit 10 has a function of controlling the start / stop of the operation of the force detector 3 and the proximity detector 2. The control unit 10 may also control the power supplied to the force detector 3 and the proximity detector 2. In addition, the optical sensor 1A may be driven by power supplied from an external power source, or may have a built-in power source such as a battery.

[0108] Fig.10 The following is a flowchart illustrating the operation of the optical sensor 1A according to the present embodiment. Figure 6 An example of operation performed under the same conditions as (A) to (E) is described below.

[0109] Fig.10 The process shown in the flowchart is started in a state where the operation of the force detection unit 3 is stopped. Each process shown in this flowchart is executed by the control unit 10 of the optical sensor 1A, for example.

[0110] First, the control unit 10 of the optical sensor 1A obtains a proximity flag from the proximity detection circuit 24 (S1), and determines whether the obtained proximity flag is "1" (S2). Step S2 is performed to determine whether the object 5 approaches within the range of the threshold distance D1.

[0111] For example, in Figure 6 In the same operation example (A) to (E), the proximity flag is "0" ("No" in S2) before the object 5 approaches the threshold distance D1, so the processing of steps S1 and S2 is repeated periodically. At this time, the force detection unit 3 is maintained in a stopped state, which can reduce power consumption. At the subsequent time t20, the proximity flag becomes "1", and the control unit 10 proceeds to "Yes" in step S2.

[0112] If the control unit 10 determines that the acquired proximity flag is "1" ("Yes" in S2), the force detection unit 3 starts to operate (S3). For example, the control unit 10 supplies power that enables the force sensor unit 13 and the force detection circuit 30 to operate. The force detection unit 3 in this embodiment starts to generate a force detection signal, for example, from step S3.

[0113] Then, the control unit 10 controls the operation of the proximity detector 2 based on the force detection signal (S4). According to step S4, the power consumption of the proximity detector 2 can also be reduced. The processing of step S4 will be described later. In addition, the processing of step S4 can also be appropriately omitted.

[0114] Next, the control unit 10 obtains the proximity flag from the proximity detection circuit 24 again (S5), and determines whether the obtained proximity flag is "1" (S6) in the same way as step S2. When the proximity flag is "1" ("Yes" in S6), the control unit 10 performs the processing after step S4 again.

[0115] exist Figure 6 In the example of (A) to (E), during the period T10 from time t20 to time t31, the proximity flag is "1" ("Yes" in S6), so the processing of steps S4 to S6 is performed. At this time, since the force detection unit 3 is in operation, the force detection unit 3 can be obtained in this embodiment. Figure 6 The force detection signal corresponding to the period T10 in (E) is obtained. At time t31, the proximity flag becomes "0", and the control unit 10 proceeds to "No" in step S6.

[0116] If the control unit 10 determines that the acquired proximity flag is "0" (No in S6), the force detection unit 3 stops operating (S7). For example, the control unit 10 stops supplying power to the force sensor unit 13 and the force detection circuit 30, or limits the power to standby power.

[0117] After stopping the operation of the force detection unit 3 (S7), the control unit 10 ends the process shown in this flowchart. For example, the control unit 10 repeats the above process at a predetermined cycle.

[0118] According to the above processing, the power control of the force detection unit 3 can be realized as follows, that is, based on the proximity flag, as long as the object 5 does not approach within the threshold distance D1 ("No" in S2), the force detection unit 3 is not operated. On the other hand, if the object 5 approaches within the threshold distance D1 ("Yes" in S2 and S6), the force detection unit 3 is activated (S3), and power saving can be achieved without failure in force detection caused by contact with the object 5.

[0119] In the above description, an example is described in which the control unit 10 acquires a proximity sign in steps S1 and S5, but the control unit 10 may acquire a light receiving signal instead. The control unit 10 can make the same determination as in steps S2 and S6 based on the acquired light receiving signal.

[0120] In the above description, an example of starting / stopping the operation of the force detection unit 3 in steps S3 and S7 is described, but the present invention is not particularly limited thereto, and various power controls for power saving of the force detection unit 3 may be performed. The control unit 10 may also limit the operation of the detection unit 3 before step S3 and in step S7 so as to reduce the power consumption of the force detection unit 3, and release the limitation of the force detection unit 3 in step S3 to cause it to operate.

[0121] use Fig.11 The above process of step S4 will be described. Fig.11 The illustrated process is executed during the operation of the force detection unit 3 .

[0122] First, the control unit 10 obtains a force detection signal from the force detection circuit 30 of the force detection unit 3 (S21), and determines whether a contact force is detected based on the obtained force detection signal (S22). For example, when no contact force is generated before the object 5 contacts, the control unit 10 proceeds to "No" in step S22 and ends. Fig.10 In this case, the operation of the proximity detector 2 continues (see step S5).

[0123] On the other hand, when the contact force is detected ("Yes" in S22), it can be considered that the object 5 is in contact with the force sensor unit 13, and the proximity detector unit 2 may not be operated. In this case, the control unit 10 controls the light source driving circuit 23 in the proximity detector unit 2 to turn off the light source 21 (S23). Thereby, the power consumption of the proximity detector unit 2 can be reduced.

[0124] Then, the control unit 10 obtains the force detection signal from the force detection circuit 30 again (S24), and determines whether the contact force is detected (S25) in the same manner as step S22. If the contact force is detected ("Yes" in S25), the control unit 10 performs the processing after step S24 again.

[0125] On the other hand, when the contact force is no longer detected (No in S25), the object 5 may be near the optical sensor 1A. In this case, in order to operate the proximity detector 2 to detect the approach of the object 5, the control unit 10 controls the light source drive circuit 23 to light up the extinguished light source 21 (S26).

[0126] If the control unit 10 operates the proximity detector 2 (S26), the process ends. Fig.10 Step S4, proceed to step S5.

[0127] According to the above processing, the following power control of the proximity detection unit 2 can be achieved, that is, based on the detection result of the force detection unit 3, if the object 5 contacts the force sensor unit 13 and the contact force is detected ("Yes" in S22 and S25), the proximity detection unit 2 will not be operated (S23).

[0128] In the above step S23, an example in which the light source 21 is extinguished is described, but it is not particularly limited to this. The control unit 10 can also perform various action restrictions to save power for the proximity detection unit 2. For example, the control unit 10 can also reduce the light amount of the light source 21, and can also reduce the gain of the sensor amplifier of the light receiving unit 22. In this case, the control unit 10 restores the reduced light amount or gain in step S26. Thereby, the action restriction of the proximity detection unit 2 can be released, and the action state can be appropriately restored.

[0129] In addition, in the above description, it is explained Fig.10 , 11 The processing shown is an example performed by the control unit 10 of the optical sensor 1A. Fig.10 , 11 The same processing can also be performed by a control system to which the optical sensor 1A is applied. In this case, a CPU or the like that executes the processing is an example of a control unit.

[0130] As described above, the optical sensor 1A of the present embodiment further includes, for example, a control unit 10 that controls the operation of the force detection unit 3 according to the light reception signal output from the light receiving unit 22 through the proximity flag. The control unit 10 operates the force detection unit 3 (S3) based on the light reception result below the threshold light amount A1 ("Yes" in S2 and S6). The control unit 10 limits the operation of the force detection unit 3 (S7) based on the light reception result exceeding the threshold light amount A1 ("No" in S2 and S6). Thus, the operation of the force detection unit 3 is limited as long as the object 5 does not approach the threshold distance D, and the power consumption caused by the force detection unit 3 can be reduced.

[0131] (Implementation 3)

[0132] In implementation mode 3, using Figures 12 to 15 An example in which an optical method is adopted as the force detection method will be described.

[0133] Fig.12 1 is a block diagram showing the structure of an optical sensor 1B according to Embodiment 3. The optical sensor 1B according to this embodiment adopts an optical force detection method for a force detection unit 3B in the same structure as the optical sensor 1A according to Embodiment 2. The force detection unit 3B according to this embodiment includes: an optical force sensor unit 13B including a light source 31 and a light receiving unit 32; a light source driving circuit 33; and a force detection circuit 30.

[0134] Fig.13 1 is a diagram for explaining a force sensor unit 13B of an optical sensor 1B in this embodiment. The optical force sensor unit 13B is formed by covering a light source 31 and a light receiving unit 32 with an elastic member 35 formed in a convex shape. Inside the force sensor unit 13B, for example, the light source 31 and the light receiving unit 32 are arranged on the substrate 11 so that the light receiving unit 32 surrounds the light source 31. The elastic member 35 is composed of various elastic bodies that are deformed according to external forces such as contact force acting when the object 5 contacts.

[0135] Fig.13 (A) illustrates a state where a force in the Z direction acts on the force sensor portion 13B. Fig.13 (B) has an effect on Fig.13 (A) The states of forces in different directions are exemplified.

[0136] In the optical force sensor unit 13B, the light source 31 emits light, and the light receiving unit 32 receives reflected light of the emitted light inside the elastic member 35. Here, if a force acts on the force sensor unit 13B, Fig.13 As illustrated in (A) and (B) of FIG. 1 , the deformation mode of the elastic member 35 changes according to the difference in the applied force.

[0137] According to the optical force sensor unit 13B, various forces can be detected based on the light receiving result of the light receiving unit 32 that changes according to the deformation of the elastic member 35. The elastic member 35 may also be provided with a reflecting unit that reflects the light from the light source 31. In addition, the reflecting unit may not be particularly provided on the elastic member 35, and the light receiving unit 32 may receive the reflected light from the object 5 when the elastic member 35 and the object 5 are in contact.

[0138] The light source 31 of the force sensor unit 13B is composed of various light-emitting elements such as VCSEL, similarly to the light source 21 of the proximity sensor unit 12. The light receiving unit 32 of the force sensor unit 13B is composed of various light receiving elements such as PD, similarly to the light receiving unit 22 of the proximity sensor unit 12, and generates a light receiving signal indicating the result of light reception. The light receiving unit 32 of the force sensor unit 13B has, for example, three or more light receiving elements, for example, four.

[0139] return Fig.12 The light source driving circuit 33 of the force detection unit 3B is configured similarly to the light source driving circuit 23 of the proximity detection unit 2. The force detection circuit 30 of this embodiment processes the light receiving elements included in the light receiving unit 32 by grouping them, and performs calculations on the difference between the light receiving signals of each group, thereby generating a force detection signal capable of detecting forces in three axes.

[0140] When the same power control as in Embodiment 2 is applied to the optical sensor 1B of this embodiment, for example, the control unit 10 performs Fig.10 In step S3, the light source 31 is turned on, and in step S7, the light source 31 is turned off. In this embodiment, the power control (S3, S7) of the optical force detector 3B can be applied to the power control (S3, S7) of the proximity detector 2. Fig.11 The same various controls as S23 and S26).

[0141] Fig.14 It is a plan view showing an example of the optical sensor 1B according to the present embodiment. Fig.15 Shown with Fig.14 A cross-sectional view of the optical sensor 1B corresponding to the line AA along the X direction.

[0142] In the optical sensor 1B of this embodiment, for example, Fig.15 As shown, the elastic member 35 includes three layers of resin bodies 35a, 35b, and 35c. The first layer of resin body 35a is made of, for example, a relatively hard resin, and seals the light source 31 and the light receiving unit 32. The second layer of resin body 35b is made of, for example, a softer resin than the first layer of resin body 35a, and seals the first layer of resin body 35a. The third layer of resin body 35c seals the second layer of resin body 35b.

[0143] In this embodiment, the light source 21 and the light receiving unit 22 of the proximity detector 2 may be sealed by resin bodies 21b and 22b, respectively. Fig.14 , 15 , an example is shown in which the resin bodies 21b and 22b are made of the same resin material as the resin body 35a of the first layer of the elastic member 35. By making the resin material for sealing the light source 21 and the light receiving unit 22 and the resin material of the elastic member 35 common, the manufacturing steps can be combined, and the manufacturing of the optical sensor 1B can be facilitated.

[0144] The resin material used to seal the light source 21 and the light receiving unit 22 may also selectively transmit the detection light L1 and the reflected light L2 (see Figure 1 ) wavelength filter characteristics. The wavelength filter characteristics of the resin bodies 21b and 22b are, for example, optical characteristics that block light of a given wavelength band that is shorter and / or longer than the peak wavelength of the detection light L1. With such resin bodies 21b and 22b, the influence of disturbance light can be easily suppressed in the proximity detection performed by the optical sensor 1B. For example, the resin body 35a of the elastic member 35 may also have the same wavelength filter characteristics as described above.

[0145] As the resin material of the resin bodies 35a, 35b, 35c, 21b, and 22b, for example, silicone resins such as methyl silicone, phenyl silicone, and modified silicone, or epoxy resin can be used. In addition, the resin material for sealing the light source 21 and the light receiving part 22 is not limited to the first layer of the elastic member 35, and can also be shared with the resin bodies 35b and 35c of other layers. The elastic member 35 is not limited to three layers, and can also include two or more layers of resin bodies.

[0146] As described above, in the optical sensor 1B of the present embodiment, the force detection unit 3B includes a light source 31 as an example of a second light source, a light receiving unit 32 as an example of a second light receiving unit, and an elastic member 35 of the force sensor unit 13B as an example of a convex portion. The light source 31 emits light inside the elastic member 35. The light receiving unit 32 receives light inside the elastic member 35. The elastic member 35 is deformed by an external force. According to the optical sensor 1B of the present embodiment, it is possible to detect the force caused by the contact of the object 5 by an optical force detection method.

[0147] In this embodiment, the elastic member 35 may include a resin body 35a as an example of a first resin body. The light source 21 and the light receiving unit 22 may be sealed by resin bodies 21b and 22b as an example of a second resin body made of a resin material common to the first resin body. This facilitates the sealing process during the manufacture of the optical sensor 1B.

[0148] In the present embodiment, the resin bodies 21b and 22b may have wavelength filter characteristics that selectively transmit the light emitted by the light source 21. This can suppress the influence of disturbance light on the optical sensor 1B.

[0149] (Other embodiments)

[0150] In each of the above-mentioned first to third embodiments, the light receiving unit 22 is provided in the proximity sensor unit 12, but an additional light receiving unit may be further provided. Fig.16 This modification example will be described.

[0151] Fig.16 The optical sensor 1C according to this modification is shown in a top view. The optical sensor 1C according to this modification has the same structure as that of the first embodiment (see Figure 2 ) is provided with an additional light receiving unit 25. Fig.16 , an example is shown in which the additional light receiving unit 25 is arranged adjacent to the light source 21. The light receiving unit 25 may be positioned at various positions capable of receiving the reflected light L2 of the probe light L1 at the threshold distance D1.

[0152] In this modification, the additional light receiving unit 25 is configured similarly to the light receiving unit 22 of the proximity sensor unit 12, and generates a light receiving signal. The optical sensor 1C may also include various circuit structures for processing the light receiving signal from the additional light receiving unit 25. Based on the light receiving signal from the additional light receiving unit 25, when the signal level of the light receiving signal of the light receiving unit 22 of the proximity sensor unit 12 is, for example, near "0", it can be determined whether the object 5 is at the threshold distance D1 or the object 5 does not exist.

[0153] Furthermore, by placing the additional light receiving unit 25 adjacent to the light source 21, it is possible to monitor changes in ambient temperature or changes in characteristics of the light source 21 due to time-dependent degradation based on the light receiving signal of the light receiving unit 25, and this can be effectively used for temperature compensation and fault detection of the optical sensor 1C.

[0154] As in the above modification, the optical sensor 1C of the present embodiment may further include a light receiving unit 25 as an example of a third light receiving unit configured to receive reflected light L2 when the probe light L1 emitted from the light source 21 is reflected at the threshold distance D1.

[0155] In the above-mentioned embodiments, the example in which the light source 21 has narrow directivity is described, but the directivity of the light source 21 is not particularly limited, and may be wide directivity. The threshold distance D1 when the light source 21 has wide directivity is shown as an example. Fig.17 In the present embodiment, the threshold distance D1 of the optical sensor 1 can be appropriately set in consideration of the directivity of the light source 21 .

[0156] In addition, in each of the above-mentioned embodiments, the optical sensor 1 is described as detecting the distance to the object 5 based on the light amount of the reflected light L2 based on the light reception signal of the light receiving unit 22 of the proximity sensor unit 12. The optical sensor of this embodiment is not limited to the light amount of the reflected light L2, and can also detect the distance to the object 5 based on the phase difference. For example, the proximity detection circuit 24 and the light source driving circuit 23 can be synchronized to detect the phase difference from the time when the detection light L1 from the light source 21 is emitted to the time when the reflected light L2 is received based on the light reception signal of the light receiving unit 22, and the phase difference corresponds to the distance to the object 5. Even in such a detection method, if the object 5 approaches within the threshold distance D1, the signal level of the light reception signal of the light receiving unit 22 becomes "0", so that the approach to the threshold distance D1 can be detected with high accuracy regardless of the reflectivity of the object 5 by using such a change in the light reception result.

[0157] In addition, in each of the above-mentioned embodiments, an example in which the convex portion of the optical sensor constitutes the force detection portion 3 is described. In the present embodiment, the convex portion of the optical sensor may not specifically constitute the force detection portion. For example, the convex portion of the optical sensor may be a component having a function different from that of the force sensor portion 13, or may be a simple structure. Even with such a convex portion, the phenomenon of shielding the reflected light L2 from the light receiving portion 22 at the threshold distance D1 can be generated in the same manner as in the above-mentioned embodiments, and the approach of the object 5 at the threshold distance D1 can be detected with high accuracy.

[0158] Description of Reference Numerals

[0159] 1. 1A, 1B, 1C optical sensors;

[0160] 10. Control Department;

[0161] 12 proximity sensor unit;

[0162] 13, 13B force sensor unit;

[0163] 21 light source;

[0164] 22 light receiving part;

[0165] 25 light receiving part;

[0166] 21b, 22b resin bodies;

[0167] 2 proximity detection unit;

[0168] 3. 3B force detection unit;

[0169] 31 light source;

[0170] 32 light receiving part;

[0171] 35 elastic member;

[0172] 35a, 35b, 35c Resin body.

Claims

1. An optical sensor that detects the approach of an object based on the result of light reception, wherein: The optical sensor comprises: a first light source emitting light toward the object; A first light receiving unit receives reflected light of the emitted light reflected from the object and generates a signal indicating a result of the light reception; and The convex portion has a height higher than the first light source and the first light receiving portion, The convex portion is arranged between the first light source and the first light receiving portion so as to shield the reflected light from the first light source when the light is reflected within a range of a given distance from the convex portion from the first light receiving portion. The first light receiving unit outputs the signal in response to the approach of the object within the predetermined distance so as to indicate a light reception result of a light amount below a threshold value indicating that the reflected light is not received. The convex portion constitutes a force detection portion that detects a force generated by contact with the object.

2. The optical sensor according to claim 1, wherein: The device further comprises: a control unit that controls the operation of the force detection unit based on the signal output from the first light receiving unit, The control unit, According to the light receiving result below the threshold light amount, the force detection unit is activated. The operation of the force detection unit is limited based on the result of receiving light exceeding the threshold light amount.

3. The optical sensor according to claim 1 or 2, wherein: The force detection unit comprises: a second light source that emits light inside the convex portion; and The second light receiving part receives light inside the convex part, The convex portion is formed of an elastic member that is deformed by an external force.

4. The optical sensor according to claim 3, wherein: The elastic member includes a first resin body, The first light source and the first light receiving unit are sealed by a second resin body including a resin material common to the first resin body.

5. The optical sensor according to claim 4, wherein: The second resin body has a wavelength filter characteristic of selectively transmitting light emitted by the first light source.

6. The optical sensor according to claim 1 or 2, wherein: The device further includes a third light receiving unit configured to receive reflected light when the light emitted from the first light source is reflected at the predetermined distance.

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