JP2018071988A - Sensor device, sensing method, program and storage medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure that the receiver of a sensor device does not simultaneously detect an electromagnetic wave reflected at a position somewhat close to the sensor device and an electromagnetic wave reflected at a position somewhat far from the sensor device.SOLUTION: An electromagnetic wave from a transmitter 100 is emitted toward the outside of a first angle range AR. A receiver 200 cannot detect an electromagnetic wave reflected at a position somewhat close to a sensor device 10, more specifically an electromagnetic wave reflected at a position apart by less than a distance R1 from the sensor device 10. More specifically, an electromagnetic wave reaches the sensor device 10 before the first angle range AR reaches an axis Y when the electromagnetic wave is reflected at the position apart by less than the distance R1 from the sensor device 10. Thus, the electromagnetic wave reflected at the position somewhat close to the sensor device 10 is not detected by the receiver 200.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a sensor device, a sensing method, a program, and a storage medium.

  In recent years, sensor devices using LIDAR (Light Detection And Ranging) have been developed. As described in Patent Document 1, a sensor device using LIDAR includes a transmitter and a receiver. The sensor device can measure the position of the object, that is, the distance between the sensor device and the object, based on the time from when the light is emitted from the transmitter and detected by the receiver. Furthermore, in the sensor apparatus of patent document 1, the light emission direction from a transmitter is changed by rotating a movable reflector. Thereby, the sensor apparatus can measure the position of a several target object.

JP 2011-95208 A

  A transmitter (for example, a laser diode (LD)) of a sensor device such as LIDAR or RADAR (Radio Detection And Ranging) emits a first electromagnetic wave, and then emits a second electromagnetic wave. In this case, when the first electromagnetic wave is reflected at a position some distance away from the sensor device and the second electromagnetic wave is reflected at a position somewhat close to the sensor device, the first electromagnetic wave and the second electromagnetic wave are substantially simultaneously reflected on the sensor device. May reach. In this case, a receiver (for example, a photodiode (PD)) of the sensor device may not be able to distinguish between the first electromagnetic wave and the second electromagnetic wave.

  An example of a problem to be solved by the present invention is to prevent the receiver of the sensor device from simultaneously detecting the electromagnetic wave reflected at a position close to the sensor device and the electromagnetic wave reflected at a position far from the sensor device. It is done.

The invention described in claim 1
A transmitter that emits electromagnetic waves;
A receiver for receiving the electromagnetic wave;
The electromagnetic wave emitted by the transmission unit at a first timing is reflected toward the receiver so that the receiver cannot receive the first reflected wave reflected by the first reflector. A movable reflector that reflects a second reflected wave reflected by a second reflector located farther away than one reflector toward the outside of the receiver so that the receiver can receive the reflected wave;
It is a sensor apparatus provided with.

The invention according to claim 3
A sensing method used by a sensor device comprising a transmitter, a receiver, and a movable reflector having a first surface and a second surface facing a direction different from the first surface,
An injection process for emitting electromagnetic waves to the transmitter; and
The movable reflection unit directs the first reflected wave, which is emitted by the transmission unit at the first timing and reflected by the first reflector, to the receiver so that the receiver cannot receive the electromagnetic wave. A reflection step of reflecting the second reflected wave reflected by the second reflector existing farther than the first reflector toward the outside of the receiver so that the receiver can receive the reflected wave; , A sensing method including

  The invention according to claim 4 is a program for causing a computer to execute the sensing method described above.

  The invention according to claim 5 is a storage medium storing the above-described program.

It is a figure which shows the sensor apparatus which concerns on embodiment. It is a figure for demonstrating the 1st example of operation | movement of the sensor apparatus shown in FIG. It is a figure for demonstrating the 1st example of operation | movement of the sensor apparatus shown in FIG. It is a figure for demonstrating the 1st example of operation | movement of the sensor apparatus shown in FIG. It is a figure for demonstrating the 2nd example of operation | movement of the sensor apparatus shown in FIG. It is a figure for demonstrating the 2nd example of operation | movement of the sensor apparatus shown in FIG. It is a figure for demonstrating the 2nd example of operation | movement of the sensor apparatus shown in FIG. It is a figure for demonstrating the 3rd example of operation | movement of the sensor apparatus shown in FIG. It is a figure for demonstrating the 3rd example of operation | movement of the sensor apparatus shown in FIG. It is a figure for demonstrating the 3rd example of operation | movement of the sensor apparatus shown in FIG. It is a figure for demonstrating the timing when electromagnetic waves are inject | emitted from the sensor apparatus shown in FIG. It is a figure for demonstrating an example of operation | movement of the sensor apparatus shown in FIG. It is a figure for demonstrating an example of operation | movement of the sensor apparatus shown in FIG. It is a figure for demonstrating an example of operation | movement of the sensor apparatus shown in FIG. It is a figure for demonstrating an example of operation | movement of the sensor apparatus shown in FIG. It is a figure for demonstrating an example of operation | movement of the sensor apparatus shown in FIG. It is a figure for demonstrating an example of the relationship between the direction which can inject the electromagnetic waves from a transmitter, and the timing of the electromagnetic waves inject | emitted from a transmitter. It is a figure which shows the modification of FIG. It is a figure for demonstrating an example of operation | movement of the sensor apparatus shown in FIG. It is a figure for demonstrating an example of operation | movement of the sensor apparatus shown in FIG. It is a figure for demonstrating an example of operation | movement of the sensor apparatus shown in FIG. It is a figure for demonstrating an example of operation | movement of the sensor apparatus shown in FIG. It is a figure for demonstrating an example of operation | movement of the sensor apparatus shown in FIG. 1 is a diagram illustrating a sensor device according to a first embodiment. It is a figure for demonstrating an example of the method in which the receiver shown in FIG. 24 detects electromagnetic waves. It is a figure for demonstrating an example of operation | movement of the sensor apparatus shown in FIG. It is a figure for demonstrating an example of operation | movement of the sensor apparatus shown in FIG. It is a figure for demonstrating an example of operation | movement of the sensor apparatus shown in FIG. It is a figure for demonstrating an example of operation | movement of the sensor apparatus shown in FIG. It is a figure for demonstrating an example of the timing which electromagnetic waves are inject | emitted from the sensor apparatus shown in FIG. It is a figure for demonstrating an example of the timing which electromagnetic waves are inject | emitted from the sensor apparatus shown in FIG. It is a figure for demonstrating an example of the timing which electromagnetic waves are inject | emitted from the sensor apparatus shown in FIG. FIG. 6 is a diagram illustrating a sensor device according to a second embodiment. It is a figure for demonstrating an example of operation | movement of the sensor apparatus shown in FIG. It is a figure for demonstrating an example of operation | movement of the sensor apparatus shown in FIG. It is a figure for demonstrating an example of operation | movement of the sensor apparatus shown in FIG. It is a figure for demonstrating an example of operation | movement of the sensor apparatus shown in FIG. It is a figure for demonstrating an example of the timing which electromagnetic waves are inject | emitted from the sensor apparatus shown in FIG. It is a figure for demonstrating an example of the timing which electromagnetic waves are inject | emitted from the sensor apparatus shown in FIG. It is a figure for demonstrating an example of the timing which electromagnetic waves are inject | emitted from the sensor apparatus shown in FIG. FIG. 10 is a diagram illustrating a sensor device according to a third embodiment. FIG. 42 is a diagram for describing an example of operation of the sensor device illustrated in FIG. 41. FIG. 42 is a diagram for describing an example of operation of the sensor device illustrated in FIG. 41. FIG. 42 is a diagram for describing an example of operation of the sensor device illustrated in FIG. 41. FIG. 42 is a diagram for describing an example of operation of the sensor device illustrated in FIG. 41. It is a figure for demonstrating an example of the timing which electromagnetic waves are inject | emitted from the sensor apparatus shown in FIG. It is a figure for demonstrating an example of the timing which electromagnetic waves are inject | emitted from the sensor apparatus shown in FIG. It is a figure for demonstrating an example of the timing which electromagnetic waves are inject | emitted from the sensor apparatus shown in FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, the same reference numerals are given to the same components, and the description will be omitted as appropriate.

  FIG. 1 is a diagram illustrating a sensor device 10 according to the embodiment. In the example shown in this figure, for the sake of explanation, the sensor device 10 is placed at the origin of XY rectangular coordinates. The sensor device 10 includes a transmitter 100 and a receiver 200.

  The transmitter 100 can emit electromagnetic waves, and is, for example, a laser diode (LD). In one example, the electromagnetic wave from the transmitter 100 is light (for example, infrared light, visible light, or ultraviolet light). In this example, the sensor device 10 can function as LIDAR (Light Detection And Ranging). In another example, the electromagnetic wave from the transmitter 100 is a radio wave. In this example, the sensor device 10 can function as RADAR (Radio Detection And Ranging).

The receiver 200 can detect an electromagnetic wave from the first angle range AR (angle θ ₁ ) outside the sensor device 10, and is, for example, a photodiode (PD), more specifically, for example, an avalanche photodiode (APD). is there. The first angle range AR rotates around the sensor device 10. In one example, the first angle range AR oscillates within a certain range. In another example, the first angular range AR rotates only in one direction, clockwise or counterclockwise. At the timing shown in the drawing, the first angle range AR rotates clockwise around the sensor device 10 at an angular velocity ω. The angular velocity ω may vary depending on time, or may be constant regardless of time.

  The sensor device 10 can measure the position of the object based on the time until the electromagnetic wave is emitted from the transmitter 100 and detected by the receiver 200. Specifically, when an electromagnetic wave is reflected by an object located at a distance R from the sensor device 10, the time until the electromagnetic wave is emitted from the sensor device 10 and returns to the sensor device 10 is 2R / c (c: Electromagnetic wave speed). For this reason, the sensor apparatus 10 can measure the position of the object, that is, the distance R based on this time.

  In the example illustrated in FIG. 1, the electromagnetic wave from the transmitter 100 is emitted toward the outside of the first angle range AR. Specifically, at the timing shown in FIG. 1, the first angle range AR does not reach the Y axis. At this timing, the electromagnetic wave from the transmitter 100 is emitted toward the first direction D1, and in the example shown in the figure, the first direction D1 is along the Y axis. In this way, in the example shown in FIG. 1, the electromagnetic wave from the transmitter 100 moves from the first angle range AR toward the traveling direction of the first angle range AR (clockwise direction in the example shown in this figure). Injected in a direction shifted by an angle Δθ.

このように、センサ装置１０からある程度近い位置で反射した電磁波は、受信器２００に検出されない（例えば、後述する図２〜図４の例）。 The receiver 200 cannot detect the electromagnetic wave reflected at a position close to the sensor device 10 to some extent, specifically, the electromagnetic wave reflected at a position less than the distance R1 from the sensor device 10. Specifically, in the case where the electromagnetic wave is emitted at the timing shown in FIG. 1, when the electromagnetic wave is reflected at a position less than the distance R1 from the sensor device 10, the electromagnetic wave has a first angle range AR in the Y axis. The sensor device 10 is reached before reaching. In other words, the following formula (1) is satisfied.

As described above, the electromagnetic wave reflected at a position somewhat close to the sensor device 10 is not detected by the receiver 200 (for example, examples of FIGS. 2 to 4 described later).

このように、センサ装置１０からある程度遠い位置で反射した電磁波は、受信器２００に検出される（例えば、後述する図５〜図７の例）。 The receiver 200 can detect an electromagnetic wave reflected at a position far away from the sensor device 10, specifically, an electromagnetic wave reflected at a position away from the sensor device 10 by a distance R1 or more and a distance R2 or less (R1 <R2). . Specifically, when an electromagnetic wave is emitted at the timing shown in the figure, when the electromagnetic wave is reflected from the sensor device 10 at a position separated by a distance R1 or more and a distance R2 or less, the electromagnetic wave has a first angle range AR of Y. The sensor device 10 is reached at a timing overlapping with the shaft. In other words, the following formula (2) is satisfied.

As described above, the electromagnetic wave reflected at a position far from the sensor device 10 is detected by the receiver 200 (for example, examples of FIGS. 5 to 7 described later).

このように、センサ装置１０から相当に遠い位置で反射した電磁波は、受信器２００に検出されない（例えば、後述する図８〜図１０の例）。 The receiver 200 cannot detect electromagnetic waves reflected at a position considerably far from the sensor device 10, specifically, electromagnetic waves reflected at a position more than the distance R <b> 2 away from the sensor device 10. Specifically, when an electromagnetic wave is emitted at the timing shown in the figure, when the electromagnetic wave is reflected at a position more than the distance R2 from the sensor device 10, the first angular range AR passes through the Y axis when the electromagnetic wave is reflected. After that, the sensor device 10 is reached. In other words, the following expression (3) is satisfied.

As described above, the electromagnetic wave reflected at a position considerably far from the sensor device 10 is not detected by the receiver 200 (for example, examples of FIGS. 8 to 10 described later).

  In the example shown in FIG. 1, the receiver 200 does not simultaneously detect the electromagnetic wave reflected at a position close to the sensor device 10 and the electromagnetic wave reflected at a position far from the sensor device 10. Specifically, as described using Expression (2), the receiver 200 can detect an electromagnetic wave reflected at a position far from the sensor device 10 to some extent. On the other hand, as described using Expression (1), the receiver 200 cannot detect the electromagnetic wave reflected at a position close to the sensor device 10 to some extent. Thus, the receiver 200 does not simultaneously detect the electromagnetic wave reflected at a position close to the sensor device 10 and the electromagnetic wave reflected at a position far from the sensor device 10.

  In one example, the distance R1 is 5 m. In this example, the receiver 200 cannot detect the electromagnetic wave reflected at a position less than 5 m from the sensor device 10.

  2-4 is a figure for demonstrating the 1st example of operation | movement of the sensor apparatus 10 shown in FIG. 2 to 4, an arrow extending from the sensor device 10 indicates an electromagnetic wave emitted from the sensor device 10, and an arrow extending from the object OB indicates an electromagnetic wave reflected by the object OB. In this example, the object OB exists at a position away from the sensor device 10 by the distance D in the first direction D1. The distance D is less than the distance R1 (D <R1). In this example, the sensing method using the sensor device 10 is performed as follows. In this sensing method, a program may be executed by a computer. In this case, the program can be stored in a storage medium. In the sensing method described later, a program may be executed by a computer, and this program can be stored in a storage medium.

  First, as shown in FIG. 2, at time t = 0, the electromagnetic wave from the transmitter 100 is emitted in the first direction D1.

  Next, as shown in FIG. 3, at time t = T, the electromagnetic wave from the transmitter 100 reaches the object OB. In other words, in this example, the speed of the electromagnetic wave is D / T.

  Next, as shown in FIG. 4, the electromagnetic wave reflected from the object OB reaches the sensor device 10 at time t = 2T. At time t = 2T, the first angle range AR has not yet reached the first direction D1. For this reason, the electromagnetic wave is not detected by the receiver 200.

  5-7 is a figure for demonstrating the 2nd example of operation | movement of the sensor apparatus 10 shown in FIG. 5-7, the arrow extended from the sensor apparatus 10 shows the electromagnetic waves inject | emitted from the sensor apparatus 10, and the arrow extended from the target object OB shows the electromagnetic waves reflected by the target object OB. In this example, the object OB exists at a position 2D away from the sensor device 10 in the first direction D1. The distance 2D is not less than the distance R1 and not more than the distance R2 (R1 ≦ 2D ≦ R2). In this example, the sensing method using the sensor device 10 is performed as follows.

  First, as shown in FIG. 5, at time t = 0, an electromagnetic wave from the transmitter 100 is emitted in the first direction D1.

  Next, as shown in FIG. 6, at time t = 2T, the electromagnetic wave from the transmitter 100 reaches the object OB. In other words, in this example, the speed of the electromagnetic wave is D / T.

  Next, as shown in FIG. 7, the electromagnetic wave reflected from the object OB reaches the sensor device 10 at time t = 4T. At time t = 4T, the first angle range AR overlaps with the first direction D1. For this reason, the electromagnetic wave is detected by the receiver 200.

  8-10 is a figure for demonstrating the 3rd example of operation | movement of the sensor apparatus 10 shown in FIG. 8-10, the arrow extended from the sensor apparatus 10 shows the electromagnetic waves inject | emitted from the sensor apparatus 10, and the arrow extended from the target object OB shows the electromagnetic waves reflected by the target object OB. In the present example, the object OB exists at a position 3D away from the sensor device 10 in the first direction D1. The distance 3D is greater than the distance R2 (R2 <3D). In this example, the sensing method using the sensor device 10 is performed as follows.

  First, as shown in FIG. 8, at time t = 0, the electromagnetic wave from the transmitter 100 is emitted in the first direction D1.

  Next, as shown in FIG. 9, at time t = 3T, the electromagnetic wave from the transmitter 100 reaches the object OB. In other words, in this example, the speed of the electromagnetic wave is D / T.

  Next, as shown in FIG. 10, the electromagnetic wave reflected from the object OB reaches the sensor device 10 at time t = 6T. At time t = 6T, the first angle range AR has already passed through the first direction D1. For this reason, the electromagnetic wave is not detected by the receiver 200.

  FIG. 11 is a diagram for explaining the timing at which electromagnetic waves are emitted from the sensor device 10 shown in FIG. In the example shown in the figure, the electromagnetic wave from the transmitter 100 is emitted in the first direction D1, and the next electromagnetic wave from the transmitter 100 is emitted in the second direction D2. The direction in which the electromagnetic wave from the transmitter 100 can be emitted fluctuates depending on time, and specifically, is synchronized with the first angle range AR.

The angle θ ₂ formed by the first direction D1 and the second direction D2 is wider than the first angle range AR (θ ₁ ), and in one example, is more than 1 times θ ₁ (θ ₂ > θ ₁ ). Thereby, even if the electromagnetic wave reflected from the first direction D1 and the electromagnetic wave reflected from the second direction D2 reach the sensor device 10 at the same time, the receiver 200 does not detect these two electromagnetic waves simultaneously.

Note that the angle θ ₂ formed by the first direction D1 and the second direction D2 may be set to be somewhat narrow as long as the above-described condition (θ ₂ > θ ₁ ) is satisfied. As a result, the number of electromagnetic waves emitted per unit time is increased.

  12-16 is a figure for demonstrating an example of operation | movement of the sensor apparatus 10 shown in FIG. 12 to 16, an arrow extending from the sensor device 10 indicates an electromagnetic wave emitted from the sensor device 10, an arrow extending from the object OB1 indicates an electromagnetic wave reflected by the object OB1, and an arrow extending from the object OB2. Indicates electromagnetic waves reflected by the object OB2. In this example, the object OB1 exists at a position 3D away from the sensor device 10 in the first direction D1. Furthermore, the object OB2 exists at a position away from the sensor device 10 by the distance D in the second direction D2. The distance D is less than the distance R1 (D <R1). The distance 3D is greater than the distance R2 (R2 <3D). In this example, the sensing method using the sensor device 10 is performed as follows.

  First, as shown in FIG. 12, at time t = 0, the electromagnetic wave from the transmitter 100 is emitted in the first direction D1. At the timing shown in the figure, the first direction D1 is shifted from the first angle range AR by the angle Δθ toward the traveling direction of the first angle range AR (clockwise direction in the example shown in the figure).

  Next, as shown in FIG. 13, at time t = 3T, the electromagnetic wave from the transmitter 100 reaches the object OB1. In other words, in this example, the speed of the electromagnetic wave is D / T.

  Next, as shown in FIG. 14, at time t = 4T, the electromagnetic wave from the transmitter 100 is emitted in the second direction D2. Further, at time t = 4T, the electromagnetic wave reflected from the object OB1 reaches a position 2D away from the sensor device 10. At the timing shown in the figure, the second direction D2 is shifted from the first angle range AR by the angle Δθ toward the traveling direction of the first angle range AR (clockwise direction in the example shown in the figure).

  Next, as shown in FIG. 15, at time t = 5T, the electromagnetic wave from the transmitter 100 reaches the object OB2. Further, at time t = 5T, the electromagnetic wave reflected from the object OB1 reaches a position away from the sensor device 10 by the distance D.

  Next, as shown in FIG. 16, at time t = 6T, the electromagnetic wave reflected from the object OB1 and the electromagnetic wave reflected from the object OB2 reach the sensor device 10 at the same time. On the other hand, at time t = 6T, the first angle range AR1 has already passed through the first direction D1, and has not yet reached the second direction D2. For this reason, neither the electromagnetic wave reflected from the object OB1 nor the electromagnetic wave reflected from the object OB2 is detected by the receiver 200.

  FIG. 17 is a diagram for explaining an example of the relationship between the direction in which the electromagnetic wave from the transmitter 100 can be emitted and the timing of the electromagnetic wave emitted from the transmitter 100. The upper graph (graph G1) in the figure shows the direction in which the electromagnetic wave from the transmitter 100 can be emitted. The lower graph (graph G2) in the figure shows the timing of the electromagnetic waves emitted from the transmitter 100.

  The direction in which the electromagnetic wave from the transmitter 100 can be emitted fluctuates depending on time, and in the example shown in the graph G1, it vibrates within a certain range. The graph G1 shows approximately ¼ period of vibration in the direction. As shown in the graph G1, the angular velocity of vibration fluctuates depending on time, and in the region shown in the graph G1, it decreases with time. In the graph G1, the direction changes by the first angle A1 in the first period P1, and changes by the second angle A2 in the second period P2. The time length of the second period P2 is equal to the time length of the first period P1. The second period P2 deviates from the first period P1, and is a period later than the first period P1 in the example shown in the graph G1. For this reason, the second angle A2 is smaller than the first angle A1.

As shown in the graph G2, the time interval of the electromagnetic waves emitted from the transmitter 100 varies depending on the time. Specifically, in the first period P1, the electromagnetic wave from the transmitter 100 and the next electromagnetic wave are emitted at the first time interval I1, and in the second period P2, the electromagnetic wave from the transmitter 100 is emitted. The next electromagnetic wave is emitted at a second time interval I2. The second time interval I2 is longer than the first time interval I1. As a result, the angle θ ₂ (2) between the direction of the electromagnetic wave emitted at the beginning of the second time interval I2 and the direction of the electromagnetic wave emitted at the end of the second time interval I2 is the beginning of the first time interval I1. The angle θ ₂ (1) formed by the direction of the emitted electromagnetic wave and the direction of the electromagnetic wave emitted at the end of the first time interval I1 can be made substantially equal.

Similarly to the angle θ ₂ shown in FIG. 11, both the angles θ ₂ (1) and θ ₂ (2) are wider than the first angle range AR (θ ₁ ). For this reason, even if the electromagnetic wave emitted at the beginning of the first time interval I1 and the electromagnetic wave emitted at the end of the first time interval I1 return to the sensor device 10 at the same time, these two electromagnetic waves are not detected by the receiver 200. Similarly, even if the electromagnetic wave emitted at the beginning of the second time interval I2 and the electromagnetic wave emitted at the end of the second time interval I2 return to the sensor device 10 at the same time, these two electromagnetic waves are not detected by the receiver 200. .

Similarly to the angle θ ₂ shown in FIG. 11, both the angles θ ₂ (1) and θ ₂ (2) are narrow to some extent. For this reason, the number of electromagnetic waves emitted per unit time is further increased.

  FIG. 18 is a diagram showing a modification of FIG. In the example shown in the figure, the electromagnetic wave from the transmitter 100 is emitted toward the inside of the first angle range AR, specifically toward the center of the first angle range AR. Specifically, at the timing shown in the drawing, the first angle range AR overlaps the Y axis. At this timing, the electromagnetic wave from the transmitter 100 is emitted toward the first direction D1, and in the example shown in the figure, the first direction D1 is along the Y axis. In this way, in the example shown in the figure, the electromagnetic wave from the transmitter 100 is emitted toward the center of the first angle range AR.

これにより、センサ装置１０から一定距離以下離れた位置で反射した電磁波は、受信器２００に検出される。 The receiver 200 can detect electromagnetic waves reflected at a position away from the sensor device 10 by a certain distance or less, specifically, electromagnetic waves reflected at a position away from the sensor device 10 by a distance R3 or less. Specifically, in the case where the electromagnetic wave is emitted at the timing shown in the figure, when the electromagnetic wave is reflected at a position away from the sensor device 10 by the distance R3 or less, the first angular range AR reaches the Y axis when the electromagnetic wave is reflected. The sensor device 10 is reached before. In other words, the following formula (4) is satisfied.

As a result, the electromagnetic wave reflected from the sensor device 10 at a position not more than a certain distance is detected by the receiver 200.

これにより、センサ装置１０から一定距離超離れた位置で反射した電磁波は、受信器２００に検出されない。 The receiver 200 cannot detect the electromagnetic wave reflected from the sensor device 10 at a position more than a certain distance, specifically, the electromagnetic wave reflected from the sensor device 10 at a position more than the distance R3. Specifically, in the case where the electromagnetic wave is emitted at the timing shown in the figure, when the electromagnetic wave is reflected at a position more than the distance R3 from the sensor device 10, the first angular range AR passes through the Y axis when the electromagnetic wave is reflected. After that, the sensor device 10 is reached. In other words, the following formula (5) is satisfied.

Thereby, the electromagnetic wave reflected from the sensor device 10 at a position more than a certain distance is not detected by the receiver 200.

  In the example shown in the figure, the electromagnetic wave from the transmitter 100 is emitted in the first direction D1, and the next electromagnetic wave from the transmitter 100 is emitted in the second direction D2. The direction in which the electromagnetic wave from the transmitter 100 can be emitted fluctuates depending on time, and specifically, is synchronized with the first angle range AR.

Similarly to the example shown in FIG. 11, the angle θ ₂ formed by the first direction D1 and the second direction D2 is wider than the first angle range AR (θ ₁ ). Thereby, even if the electromagnetic wave reflected from the first direction D1 and the electromagnetic wave reflected from the second direction D2 reach the sensor device 10 at the same time, the receiver 200 does not detect these two electromagnetic waves simultaneously.

In analogy to the example shown in FIG. 11, the first direction D1 angle theta ₂ in the second direction D2 is somewhat narrow. As a result, the number of electromagnetic waves emitted per unit time is increased.

  19-23 is a figure for demonstrating an example of operation | movement of the sensor apparatus 10 shown in FIG. 19 to 23, an arrow extending from the sensor device 10 indicates an electromagnetic wave emitted from the sensor device 10, an arrow extending from the object OB1 indicates an electromagnetic wave reflected by the object OB1, and an arrow extending from the object OB2. Indicates electromagnetic waves reflected by the object OB2. In this example, the object OB1 exists at a position 4D away from the sensor device 10 in the first direction D1. Furthermore, the object OB2 exists at a position away from the sensor device 10 by the distance D in the second direction D2. The distance D is not more than the distance R3 (D ≦ R3). The distance 4D is greater than the distance R3 (R3 <4D). In this example, the sensing method using the sensor device 10 is performed as follows.

  First, as shown in FIG. 19, at time t = 0, the electromagnetic wave from the transmitter 100 is emitted in the first direction D1. Note that, at the timing shown in the drawing, the first direction D1 overlaps the central direction of the first angle range AR.

  Next, as shown in FIG. 20, at time t = 4T, the electromagnetic wave from the transmitter 100 reaches the object OB1. In other words, in this example, the speed of the electromagnetic wave is D / T.

  Next, as shown in FIG. 21, at time t = 6T, the electromagnetic wave from the transmitter 100 is emitted in the second direction D2. Further, at time t = 6T, the electromagnetic wave reflected from the object OB1 reaches a position 2D away from the sensor device 10. Note that, at the timing shown in the drawing, the second direction D2 overlaps the central direction of the first angle range AR.

  Next, as shown in FIG. 22, at time t = 7T, the electromagnetic wave from the transmitter 100 reaches the object OB2. Further, at time t = 7T, the electromagnetic wave reflected from the object OB1 reaches a position away from the sensor device 10 by the distance D.

  Next, as shown in FIG. 23, at time t = 8T, the electromagnetic wave reflected from the object OB1 and the electromagnetic wave reflected from the object OB2 reach the sensor device 10 simultaneously. On the other hand, at time t = 8T, the first angle range AR1 has already passed through the first direction D1 and overlapped with the second direction D2. For this reason, the electromagnetic wave reflected from the object OB1 is not detected by the receiver 200, and the electromagnetic wave reflected from the object OB2 is detected by the receiver 200. In other words, the receiver 200 does not detect these two electromagnetic waves at the same time.

  As described above, according to the present embodiment, the electromagnetic wave reflected at a position somewhat close to the sensor device 10 is not detected by the receiver 200, and the electromagnetic wave reflected at a position far from the sensor device 10 is detected by the receiver 200. . For this reason, it is possible to prevent the receiver 200 from simultaneously detecting the electromagnetic wave reflected at a position close to the sensor device 10 and the electromagnetic wave reflected at a position far from the sensor device 10.

Example 1
FIG. 24 is a diagram illustrating the sensor device 10 according to the first embodiment, and corresponds to FIG. 1 of the embodiment.

  The sensor device 10 includes a transmitter 100, a receiver 200, and a movable reflector 310. The transmitter 100 is, for example, an LD. The receiver 200 is an APD, for example, and has a surface 212. The receiver 200 can detect the electromagnetic wave irradiated on the surface 212. The movable reflector 310 is a MEMS (Micro-Electro Mechanical Systems) vibrating mirror, for example, and has a first surface 312. The movable reflector 310 can reflect electromagnetic waves by the first surface 312. In one example, the angular velocity of vibration of the movable reflector 310 (first surface 312) varies depending on time as shown in the graph G1 of FIG.

  The electromagnetic wave from the transmitter 100 is reflected by the first surface 312 of the movable reflector 310 and is emitted toward the outside of the sensor device 10. The electromagnetic wave reflected by the object OB is reflected by the first surface 312 of the movable reflector 310 and received (received) by the receiver 200. Here, when the electromagnetic wave reflected by the object OB is within the first angle range AR (that is, a range that can be received by the receiver 200), the electromagnetic wave is received by the receiver 200. In other words, the receiver 200 is positioned so as to detect (receive) an electromagnetic wave from a direction different from the direction in which the electromagnetic wave from the transmitter 100 is emitted. Thereby, the electromagnetic waves from the transmitter 100 are emitted toward the outside of the first angle range AR. Further, the direction in which the electromagnetic wave from the transmitter 100 can be emitted is synchronized with the first angle range AR.

  FIG. 25 is a diagram for describing an example of a method in which the receiver 200 illustrated in FIG. 24 detects electromagnetic waves. In the example shown in the figure, the receiver 200 can detect the electromagnetic wave A and the electromagnetic wave B, but cannot detect the electromagnetic wave C. Specifically, the receiver 200 can detect an electromagnetic wave when the center of the electromagnetic wave overlaps the surface 212.

  In the example shown in the figure, the full width at half maximum of the electromagnetic wave A overlaps with the surface 212, and therefore the center of the electromagnetic wave A overlaps with the surface 212. Thereby, the receiver 200 can detect the electromagnetic wave A.

  In the example shown in the figure, a part (approximately half) of the full width at half maximum of the electromagnetic wave B does not overlap the surface 212, but the center of the electromagnetic wave B overlaps the surface 212. Thereby, the receiver 200 can detect the electromagnetic wave B.

  In the example shown in this figure, most of the full width at half maximum of the electromagnetic wave C does not overlap with the surface 212, and the center of the electromagnetic wave C does not overlap with the surface 212. As a result, the receiver 200 cannot detect the electromagnetic wave C.

  26 to 29 are diagrams for explaining an example of the operation of the sensor device 10 shown in FIG. In this example, the sensing method using the sensor device 10 is performed as follows.

  When the sensor device 10 according to the embodiment is the same as the sensor device 10 according to the present example, in the example illustrated in FIGS. 2 to 4, the sensor device 10 is illustrated in FIG. 26 at the timing illustrated in FIG. 2. 27 and operates as shown in FIG. 27 at the timing shown in FIG.

  First, as shown in FIG. 26, at time t = 0, the electromagnetic wave from the transmitter 100 is reflected by the first surface 312 of the movable reflector 310. Thereby, the electromagnetic waves from the transmitter 100 are emitted in the first direction D1.

  Next, as shown in FIG. 27, the electromagnetic wave from the first direction D1 is reflected by the first surface 312 of the movable reflector 310 at time t = 2T. This electromagnetic wave does not irradiate the surface 212 of the receiver 200 and deviates from the surface 212 toward one side of the surface 212. Thereby, this electromagnetic wave is not detected by the receiver 200. Note that the electromagnetic wave shown in FIG. 27 is when the object OB exists at a position close to the sensor device 10 (the object OB is separated by less than the distance R1 as in FIGS. 2 to 4 in the embodiment). Electromagnetic wave reflected by the object OB in the case where the object OB is present at a certain position.

  When the sensor device 10 according to the embodiment is the same as the sensor device 10 according to the present example, in the example illustrated in FIGS. 5 to 7, the sensor device 10 is illustrated in FIG. 26 at the timing illustrated in FIG. 5. 28, and operates as shown in FIG. 28 at the timing shown in FIG.

  First, as shown in FIG. 26, at time t = 0, the electromagnetic wave from the transmitter 100 is reflected by the first surface 312 of the movable reflector 310. Thereby, the electromagnetic waves from the transmitter 100 are emitted in the first direction D1.

  Next, as shown in FIG. 28, the electromagnetic wave from the first direction D1 is reflected by the first surface 312 of the movable reflector 310 at time t = 4T. This electromagnetic wave is applied to the surface 212 of the receiver 200. Thereby, this electromagnetic wave is detected by the receiver 200. Note that the electromagnetic wave shown in FIG. 28 is obtained when the object OB exists within a detectable range of the sensor device 10 (the object OB has a distance R1 as shown in FIGS. 5 to 7 in the embodiment). The electromagnetic wave reflected by the object OB in the case where it exists at a position separated by R2 or less.

  When the sensor device 10 according to the embodiment is the same as the sensor device 10 according to the present embodiment, in the example illustrated in FIGS. 8 to 10, the sensor device 10 is illustrated in FIG. 26 at the timing illustrated in FIG. 8. The operation is as shown in FIG. 29 at the timing shown in FIG.

  First, as shown in FIG. 26, at time t = 0, the electromagnetic wave from the transmitter 100 is reflected by the first surface 312 of the movable reflector 310. Thereby, the electromagnetic waves from the transmitter 100 are emitted in the first direction D1.

  Next, as shown in FIG. 29, at time t = 6T, the electromagnetic wave from the first direction D1 is reflected by the first surface 312 of the movable reflector 310. This electromagnetic wave does not irradiate the surface 212 of the receiver 200 and deviates from the surface 212 toward the other side of the surface 212. Thereby, this electromagnetic wave is not detected by the receiver 200. Note that the electromagnetic wave shown in FIG. 29 is obtained when the object OB exists at a position far away from the sensor device 10 (the object OB exceeds the distance R2 as in FIGS. 8 to 10 in the embodiment). Electromagnetic wave reflected by the object OB in the case of being present at a distant position.

  30 to 32 are diagrams for explaining an example of timing at which electromagnetic waves are emitted from the sensor device 10 shown in FIG. In this example, the sensing method using the sensor device 10 is performed as follows.

  When the sensor device 10 according to the embodiment is the same as the sensor device 10 according to the present example, in the example illustrated in FIGS. 12 to 16, the sensor device 10 is configured as illustrated at 30 at the timing illustrated in FIG. 12. It operates as shown in FIG. 31 at the timing shown in FIG. 14, and as shown in FIG. 32 at the timing shown in FIG.

  First, as shown in FIG. 30, at time t = 0, the electromagnetic wave from the transmitter 100 is reflected by the first surface 312 of the movable reflector 310. Thereby, the electromagnetic waves from the transmitter 100 are emitted in the first direction D1.

  Next, as shown in FIG. 31, the electromagnetic wave from the transmitter 100 is reflected by the first surface 312 of the movable reflector 310 at time t = 4T. Thereby, the electromagnetic waves from the transmitter 100 are emitted in the second direction D2.

  Next, as shown in FIG. 32, at time t = 6T, the electromagnetic wave from the first direction D1 and the electromagnetic wave from the second direction D2 are reflected by the first surface 312. The electromagnetic wave from the second direction D2 does not irradiate the surface 212 of the receiver 200 and deviates from the surface 212 toward one side of the surface 212. The electromagnetic wave from the first direction D1 does not irradiate the surface 212 of the receiver 200 and deviates from the surface 212 toward the other side of the surface 212. Thereby, these electromagnetic waves are not detected by the receiver 200. Note that the electromagnetic wave from the first direction D1 shown in FIG. 32 is obtained when the object OB exists at a position far away from the sensor device 10 (as in FIGS. 8 to 10 in the embodiment). The electromagnetic wave reflected by the object OB in the case where the object OB exists at a position more than the distance R2), and the electromagnetic wave from the second direction D2 shown in FIG. The electromagnetic wave reflected by the object OB when it is present at a position close to 10 (when the object OB is present at a position less than the distance R1 as in FIGS. 2 to 4 in the embodiment). It is.

(Example 2)
FIG. 33 is a diagram illustrating the sensor device 10 according to the second embodiment and corresponds to FIG. 1 of the embodiment. The sensor device 10 according to the present embodiment is the same as the sensor device 10 according to the embodiment except for the following points.

  The sensor device 10 includes a transmitter 100, a receiver 200, and a movable reflector 310. The transmitter 100 is, for example, an LD. The receiver 200 is an APD, for example, and has a surface 212. The receiver 200 can detect the electromagnetic wave irradiated on the surface 212. The movable reflector 310 is, for example, a MEMS (Micro-Electro Mechanical Systems) vibrating mirror, and has a first surface 312 and a second surface 314. The second surface 314 faces a different direction from the first surface 312. The movable reflector 310 can reflect electromagnetic waves by the first surface 312 or the second surface 314.

  The electromagnetic wave from the transmitter 100 is reflected toward the outside of the sensor device 10 by the first surface 312 of the movable reflector 310. The electromagnetic wave from the first angle range AR is reflected toward the receiver 200 by the second surface 314 of the movable reflector 310. In other words, the receiver 200 is positioned so as to be able to detect electromagnetic waves from a direction different from the direction in which the electromagnetic waves from the transmitter 100 are emitted. Thereby, the electromagnetic waves from the transmitter 100 are emitted toward the outside of the first angle range AR. Further, the direction in which the electromagnetic wave from the transmitter 100 can be emitted is synchronized with the first angle range AR.

  34 to 37 are diagrams for explaining an example of the operation of the sensor device 10 shown in FIG. In this example, the sensing method using the sensor device 10 is performed as follows.

  When the sensor device 10 according to the embodiment is the same as the sensor device 10 according to the present example, in the example illustrated in FIGS. 2 to 4, the sensor device 10 is illustrated in FIG. 34 at the timing illustrated in FIG. 2. And operates as shown in FIG. 35 at the timing shown in FIG.

  First, as shown in FIG. 34, at time t = 0, the electromagnetic wave from the transmitter 100 is reflected by the first surface 312 of the movable reflector 310. Thereby, the electromagnetic waves from the transmitter 100 are emitted in the first direction D1.

  Next, as shown in FIG. 35, the electromagnetic wave from the first direction D1 is reflected by the second surface 314 of the movable reflector 310 at time t = 2T. This electromagnetic wave does not irradiate the surface 212 of the receiver 200 and deviates from the surface 212 toward one side of the surface 212. Thereby, this electromagnetic wave is not detected by the receiver 200.

  When the sensor device 10 according to the embodiment is the same as the sensor device 10 according to the present example, in the example illustrated in FIGS. 5 to 7, the sensor device 10 is illustrated in FIG. 34 at the timing illustrated in FIG. 5. 36, and operates as shown in FIG. 36 at the timing shown in FIG.

  First, as shown in FIG. 34, at time t = 0, the electromagnetic wave from the transmitter 100 is reflected by the first surface 312 of the movable reflector 310. Thereby, the electromagnetic waves from the transmitter 100 are emitted in the first direction D1.

  Next, as shown in FIG. 36, at time t = 4T, the electromagnetic wave from the first direction D1 is reflected by the second surface 314 of the movable reflector 310. This electromagnetic wave is applied to the surface 212 of the receiver 200. Thereby, this electromagnetic wave is detected by the receiver 200.

  When the sensor device 10 according to the embodiment is the same as the sensor device 10 according to the present example, in the example illustrated in FIGS. 8 to 10, the sensor device 10 is illustrated in FIG. 34 at the timing illustrated in FIG. 8. 37 and operates as shown in FIG. 37 at the timing shown in FIG.

  First, as shown in FIG. 34, at time t = 0, the electromagnetic wave from the transmitter 100 is reflected by the first surface 312 of the movable reflector 310. Thereby, the electromagnetic waves from the transmitter 100 are emitted in the first direction D1.

  Next, as shown in FIG. 37, at time t = 6T, the electromagnetic wave from the first direction D1 is reflected by the second surface 314 of the movable reflector 310. This electromagnetic wave does not irradiate the surface 212 of the receiver 200 and deviates from the surface 212 toward the other side of the surface 212. Thereby, this electromagnetic wave is not detected by the receiver 200.

  38 to 40 are diagrams for explaining an example of timing at which electromagnetic waves are emitted from the sensor device 10 shown in FIG. In this example, the sensing method using the sensor device 10 is performed as follows.

  When the sensor device 10 according to the embodiment is the same as the sensor device 10 according to the present example, in the example illustrated in FIGS. It operates as shown in FIG. 39 at the timing shown in FIG. 14, and as shown in FIG. 40 at the timing shown in FIG.

  First, as shown in FIG. 38, at time t = 0, the electromagnetic wave from the transmitter 100 is reflected by the first surface 312 of the movable reflector 310. Thereby, the electromagnetic waves from the transmitter 100 are emitted in the first direction D1.

  Next, as shown in FIG. 39, the electromagnetic wave from the transmitter 100 is reflected by the first surface 312 of the movable reflector 310 at time t = 4T. Thereby, the electromagnetic waves from the transmitter 100 are emitted in the second direction D2.

  Next, as shown in FIG. 40, at time t = 6T, the electromagnetic wave from the first direction D1 and the electromagnetic wave from the second direction D2 are reflected by the second surface 314. The electromagnetic wave from the second direction D2 does not irradiate the surface 212 of the receiver 200 and deviates from the surface 212 toward one side of the surface 212. The electromagnetic wave from the first direction D1 does not irradiate the surface 212 of the receiver 200 and deviates from the surface 212 toward the other side of the surface 212. Thereby, these electromagnetic waves are not detected by the receiver 200.

(Example 3)
FIG. 41 is a diagram illustrating the sensor device 10 according to the third embodiment and corresponds to FIG. 1 of the embodiment. The sensor device 10 according to the present embodiment is the same as the sensor device 10 according to the embodiment except for the following points.

  The sensor device 10 includes a transmitter 100, a receiver 200, and a rotor 320. The transmitter 100 is, for example, an LD. The receiver 200 is an APD, for example. The transmitter 100 and the receiver 200 are mounted on the rotor 320. As a result, the transmitter 100 and the receiver 200 rotate at an angular velocity equal to the angular velocity of the rotor 320 with respect to the rotation axis of the rotor 320. In other words, the rotor 320 functions as a driver that rotates the transmitter 100 and the receiver 200. In this way, the direction in which the electromagnetic wave from the transmitter 100 can be emitted is synchronized with the first angle range AR. In one example, the angular velocity of the rotor 320 is constant regardless of time.

  The transmitter 100 and the receiver 200 are mounted on the rotor 320 such that the electromagnetic wave from the transmitter 100 can be emitted and the first angle range AR of the receiver 200 faces the outside of the sensor device 10. For this reason, when the rotor 320 rotates, the transmitter 100 and the receiver 200 are in a state in which the electromagnetic wave from the transmitter 100 can be emitted and the first angle range AR of the receiver 200 faces the outside of the sensor device 10. Rotate with.

  Furthermore, the transmitter 100 and the receiver 200 are mounted on the rotor 320 so that the direction in which the electromagnetic wave from the transmitter 100 can be emitted faces the outside of the first angle range AR of the receiver 200. Thereby, the electromagnetic waves from the transmitter 100 are emitted toward the outside of the first angle range AR.

  42 to 45 are diagrams for explaining an example of the operation of the sensor device 10 shown in FIG. In this example, the sensing method using the sensor device 10 is performed as follows.

  When the sensor device 10 according to the embodiment is the same as the sensor device 10 according to the present example, in the example illustrated in FIGS. 2 to 4, the sensor device 10 is illustrated in FIG. And operates as shown in FIG. 43 at the timing shown in FIG.

  First, as shown in FIG. 42, at time t = 0, the electromagnetic wave from the transmitter 100 is emitted in the first direction D1.

  Next, as shown in FIG. 43, the electromagnetic wave from the first direction D1 reaches the receiver 200 at time t = 2T. At time t = 2T, the first angle range AR has not yet reached the first direction D1. Thereby, this electromagnetic wave is not detected by the receiver 200.

  When the sensor device 10 according to the embodiment is the same as the sensor device 10 according to this embodiment, in the example illustrated in FIGS. 5 to 7, the sensor device 10 is illustrated in FIG. 42 at the timing illustrated in FIG. 44 and operates as shown in FIG. 44 at the timing shown in FIG.

  First, as shown in FIG. 42, at time t = 0, the electromagnetic wave from the transmitter 100 is emitted in the first direction D1.

  Next, as shown in FIG. 44, the electromagnetic wave from the first direction D1 reaches the receiver 200 at time t = 4T. At time t = 4T, the first angle range AR overlaps with the first direction D1. Thereby, this electromagnetic wave is detected by the receiver 200.

  When the sensor device 10 according to the embodiment is the same as the sensor device 10 according to this example, in the example illustrated in FIGS. 8 to 10, the sensor device 10 is illustrated in FIG. 42 at the timing illustrated in FIG. And operates as shown in FIG. 45 at the timing shown in FIG.

  First, as shown in FIG. 42, at time t = 0, the electromagnetic wave from the transmitter 100 is emitted in the first direction D1.

  Next, as shown in FIG. 45, the electromagnetic wave from the first direction D1 reaches the receiver 200 at time t = 6T. At time t = 6T, the first angle range AR has already passed through the first direction D1. Thereby, this electromagnetic wave is not detected by the receiver 200.

  46 to 48 are diagrams for explaining an example of timing at which electromagnetic waves are emitted from the sensor device 10 shown in FIG. In this example, the sensing method using the sensor device 10 is performed as follows.

  When the sensor device 10 according to the embodiment is the same as the sensor device 10 according to the present embodiment, in the example illustrated in FIGS. It operates as shown in FIG. 47 at the timing shown in FIG. 14, and as shown in FIG. 48 at the timing shown in FIG.

  First, as shown in FIG. 46, at time t = 0, the electromagnetic wave from the transmitter 100 is emitted in the first direction D1.

  Next, as shown in FIG. 47, at time t = 4T, the electromagnetic wave from the transmitter 100 is emitted in the second direction D2.

  Next, as shown in FIG. 48, at time t = 6T, the electromagnetic wave from the first direction D1 and the electromagnetic wave from the second direction D2 reach the receiver 200. At time t = 6T, the first angle range AR1 has already passed through the first direction D1, and has not yet reached the second direction D2. Thereby, these electromagnetic waves are not detected by the receiver 200.

  As mentioned above, although embodiment and the Example were described with reference to drawings, these are illustrations of this invention and can also employ | adopt various structures other than the above.

10 sensor device 100 transmitter 200 receiver 212 surface 310 movable reflector 312 first surface 314 second surface 320 rotor

Claims (5)

A transmitter that emits electromagnetic waves;
A receiver for receiving the electromagnetic wave;
The electromagnetic wave emitted by the transmission unit at a first timing is reflected toward the receiver so that the receiver cannot receive the first reflected wave reflected by the first reflector. A movable reflector that reflects a second reflected wave reflected by a second reflector located farther away than one reflector toward the outside of the receiver so that the receiver can receive the reflected wave;
A sensor device comprising: The sensor device according to claim 1,
The movable reflecting portion has a first surface and a second surface facing a direction different from the first surface,
The electromagnetic wave emitted by the transmission note is emitted toward the outside by being reflected by the first surface,
The first reflected wave and the second reflection are reflected by the second surface,
Sensor device. A sensing method used by a sensor device comprising a transmitter, a receiver, and a movable reflector having a first surface and a second surface facing a direction different from the first surface,
An injection process for emitting electromagnetic waves to the transmitter; and
The movable reflection unit directs the first reflected wave, which is emitted by the transmission unit at the first timing and reflected by the first reflector, to the receiver so that the receiver cannot receive the electromagnetic wave. A reflection step of reflecting the second reflected wave reflected by the second reflector existing farther than the first reflector toward the outside of the receiver so that the receiver can receive the reflected wave; , Including a sensing method.   A program for causing a computer to execute the sensing method according to claim 3.   A storage medium storing the program according to claim 4.

Images