WO2019017379A1

WO2019017379A1 - Sensor device and sensing method

Info

Publication number: WO2019017379A1
Application number: PCT/JP2018/026887
Authority: WO
Inventors: 真生大関; 祥太椙村; 松田　武浩; 健一花田; 吉田　裕司; 陽河野
Original assignee: パイオニア株式会社
Priority date: 2017-07-19
Filing date: 2018-07-18
Publication date: 2019-01-24

Abstract

In the present invention, a movable reflector (300) can reflect, in one direction toward an object (O), electromagnetic waves emitted from a transmitter (100), and can reflect, toward a direction different from the one direction, electromagnetic waves reflected from the object (O). A receiver (200) includes a first receiving element (210) and a second receiving element (220), and the first receiving element (210) and the second receiving element (220) are mutually offset to opposite sides with respect to a virtual axis (A). The virtual axis (A) is an axis along which can pass the electromagnetic waves that were reflected from the object (O) and then reflected by the movable reflector (300) oriented in the one direction.

Description

Sensor device and sensing method

The present invention relates to a sensor device and a sensing method.

The sensor arrangement may measure the distance to the object, in particular light may be used to measure the distance to the object. Patent Document 1 describes that light is emitted from a transmitter (laser light source) toward an object, and light reflected from the object is received by a receiver (for example, an avalanche photodiode (APD)). ing. In this case, the distance from the sensor device to the object can be measured based on the time required for the light to be emitted from the transmitter and to be received by the receiver. In an example of Patent Document 1, light emitted from a transmitter is reflected toward a target by a movable reflector (for example, a MEMS (Micro Electro Mechanical Systems) mirror), and light reflected from the target is reflected. It is reflected towards the receiver by the same movable reflector.

JP 2011-95208 A

The inventor of the present invention is to reflect the electromagnetic wave (for example, light) emitted from the transmitter and the electromagnetic wave (for example, light) reflected from the object by a common movable reflector as in the above-mentioned example of Patent Document 1. In particular, it was considered to measure the distance from the sensor device to an object that was somewhat large distance away. The inventor of the present invention can move the electromagnetic wave emitted from the transmitter to the movable reflector when the object is at a certain distance (that is, the time required for the electromagnetic wave to be emitted from the sensor device to return to the sensor device is somewhat long). It has been found that the direction of the movable reflector changes between the time when the movable reflector reflects and the time when the movable reflector reflects the electromagnetic wave reflected from the object. The inventor examined a structure capable of widening the range in which the receiver can receive an electromagnetic wave even if the orientation of the movable reflector changes in this manner.

One of the problems to be solved by the present invention is to widen the range in which the receiver can receive an electromagnetic wave even if the object is far from the sensor device by a certain distance.

The invention according to claim 1 is
A transmitter,
A receiver,
The movable electromagnetic wave emitted from the transmitter can be reflected in one direction toward an object, and the electromagnetic wave reflected from the object can be reflected in a direction different from the one direction. A reflector,
Equipped with
The receiver is disposed at a position opposite to each other across an imaginary axis through which an electromagnetic wave reflected from the object and reflected by the movable reflector facing the one direction can pass. It is a sensor apparatus containing a part and a 2nd receiving part.

The invention according to claim 4 is
A transmitter that emits an electromagnetic wave,
An electromagnetic wave emitted from the transmitter can be reflected in one direction toward an object, and a movable reflection capable of reflecting the electromagnetic wave reflected from the object in a direction different from the one direction can be reflected. And the
A reflector for reflecting the electromagnetic wave reflected by the object;
A receiver for receiving the electromagnetic wave reflected by the object and the electromagnetic wave reflected by the reflector;
Equipped with
The receiver and the reflector are disposed at mutually opposing positions with an imaginary axis through which an electromagnetic wave reflected from the object and reflected by the movable reflector facing the one direction can pass. Sensor device.

The invention according to claim 5 is
A transmitter,
A receiver,
A first reflector,
A second reflector,
The movable electromagnetic wave emitted from the transmitter can be reflected in one direction toward an object, and the electromagnetic wave reflected from the object can be reflected in a direction different from the one direction. A reflector,
Equipped with
The first reflector and the second reflector are opposed to each other across an imaginary axis through which the electromagnetic wave reflected from the object and reflected by the movable reflector facing the one direction can pass. Are located in
The receiver is a sensor device capable of receiving the electromagnetic wave reflected by the first reflector and the second reflector from the movable reflector.

The invention according to claim 6 is
A transmitter capable of emitting an electromagnetic wave in one direction,
A receiver capable of receiving electromagnetic waves from two directions shifted from the one direction to the other side;
Equipped with
At the first timing, the receiver directs one of the two directions to an object, and receives an electromagnetic wave emitted from the transmitter and reflected from the object,
At the second timing, the receiver is a sensor device that directs the other of the two directions to the object, and receives an electromagnetic wave emitted from the transmitter and reflected from the object.

The invention according to claim 7 is
A transmitter, a receiver, and a movable reflector are prepared, and an electromagnetic wave emitted from the transmitter is reflected toward the object by the movable reflector, and is reflected from the object to be reflected by the movable reflector. Receiving by the receiver the electromagnetic wave reflected by
The movable reflector can reflect the electromagnetic wave emitted from the transmitter in one direction toward the object, and can reflect the electromagnetic wave reflected from the object in a direction different from the one direction. Facing and reflecting,
The receiver is disposed at a position opposite to each other across an imaginary axis through which an electromagnetic wave reflected from the object and reflected by the movable reflector facing the one direction can pass. A sensing method including a unit and a second receiving unit.

The invention according to claim 8 is
A transmitter, a receiver, a reflector, and a movable reflector are provided, and an electromagnetic wave emitted from the transmitter is reflected by the movable reflector toward the object, and is reflected from the object. Receiving the electromagnetic wave reflected by the movable reflector by the receiver;
The movable reflector can reflect the electromagnetic wave emitted from the transmitter in one direction toward the object, and can reflect the electromagnetic wave reflected from the object in a direction different from the one direction. Facing and reflecting,
The receiver and the reflector are disposed at mutually opposing positions with an imaginary axis through which an electromagnetic wave reflected from the object and reflected by the movable reflector facing the one direction can pass. Yes,
The receiver is a sensing method capable of receiving the electromagnetic wave reflected by the movable reflector from the movable reflector and the electromagnetic wave reflected by the reflector from the movable reflector.

The invention according to claim 9 is
A transmitter, a receiver, a first reflector, a second reflector, and a movable reflector are provided, and an electromagnetic wave emitted from the transmitter is reflected toward the object by the movable reflector. Receiving by the receiver the electromagnetic waves reflected from the object and reflected by the movable reflector,
The movable reflector can reflect the electromagnetic wave emitted from the transmitter toward the one direction toward the object, and the electromagnetic wave reflected from the object may face the direction different from the one direction. Can be reflected,
The first reflector and the second reflector are opposed to each other across an imaginary axis through which the electromagnetic wave reflected from the object and reflected by the movable reflector facing the one direction can pass. Are located in
The receiver may be a sensing method capable of receiving the electromagnetic wave reflected by the first reflector and the second reflector from the movable reflector.

The invention according to claim 10 is
Preparing a transmitter and a receiver, emitting an electromagnetic wave from the transmitter to an object, and receiving the electromagnetic wave reflected from the object by the receiver;
The transmitter can emit the electromagnetic wave in one direction,
The receiver can receive electromagnetic waves from two directions shifted from the one direction to the opposite side,
At the first timing, the receiver directs one of the two directions to an object, and receives an electromagnetic wave emitted from the transmitter and reflected from the object,
At a second timing, the receiver is a sensing method in which the other of the two directions is directed to the object, and the receiver receives an electromagnetic wave emitted from the transmitter and reflected from the object.

The objects described above, and other objects, features and advantages will become more apparent from the preferred embodiments described below and the following drawings associated therewith.

FIG. 2 is a view for explaining a sensor device according to Embodiment 1. FIG. 2 is a view for explaining a sensor device according to Embodiment 1. FIG. 2 is a view for explaining a sensor device according to Embodiment 1. It is a figure for demonstrating an example of the function of the sensor apparatus shown to FIGS. 1-3. It is a diagram for explaining the relationship between the functions of the movable reflectors of the resonant frequency f ₀ and the sensor device. It is a diagram for explaining the relationship between the functions of the movable reflectors of the resonant frequency f ₀ and the sensor device. It is a diagram for explaining the relationship between the functions of the movable reflectors of the resonant frequency f ₀ and the sensor device. It is a figure for demonstrating an example of the function of the sensor apparatus shown to FIGS. 1-3. It is a figure for demonstrating the 1st example of the detail of a receiver. It is a figure for demonstrating the 2nd example of the detail of a receiver. It is a figure for demonstrating the 3rd example of the detail of a receiver. FIG. 6 is a view for explaining a sensor device according to a second embodiment. FIG. 6 is a view for explaining a sensor device according to a second embodiment. FIG. 6 is a view for explaining a sensor device according to a second embodiment. It is a figure for demonstrating the sensor apparatus which concerns on Embodiment 3. FIG. It is a figure for demonstrating the sensor apparatus which concerns on Embodiment 3. FIG. It is a figure for demonstrating the sensor apparatus which concerns on Embodiment 3. FIG. FIG. 14 is a view for explaining a sensor device according to a fourth embodiment. FIG. 14 is a view for explaining a sensor device according to a fourth embodiment. FIG. 14 is a view for explaining a sensor device according to a fourth embodiment. It is a figure for demonstrating the sensor apparatus which concerns on an Example. It is a figure for demonstrating the sensor apparatus which concerns on an Example. It is a figure for demonstrating the sensor apparatus which concerns on an Example. It is a figure for demonstrating the sensor apparatus which concerns on an Example. It is a figure for demonstrating the sensor apparatus which concerns on an Example.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, the same components are denoted by the same reference numerals, and the description thereof will be appropriately omitted.

(Embodiment 1)
FIGS. 1, 2 and 3 are diagrams for explaining the sensor device 10 according to the first embodiment.

The sensing method used by the sensor device 10 will be described. The sensor device 10 comprises a transmitter 100, a receiver 200, a movable reflector 300, a beam splitter (BS) 400 and a lens 500. The transmitter 100 can transmit an electromagnetic wave. The electromagnetic waves transmitted from the transmitter 100 are reflected by the BS 400 and reach the movable reflector 300. The movable reflector 300 is rockable, and can deflect the electromagnetic wave reflected by the movable reflector 300. The electromagnetic wave reflected by the movable reflector 300 passes through the lens 500 and reaches the object O. The electromagnetic wave reflected from the object O passes through the lens 500, is reflected by the movable reflector 300, passes through the BS 400, and reaches the receiver 200. That is, this sensing method has a receiving step, in which the electromagnetic wave emitted from the transmitter 100 is reflected toward the object O by the movable reflector 300 and reflected from the object O An electromagnetic wave is received by the receiver 200. The receiver 200 includes a first receiving element 210 and a second receiving element 220, and the first receiving element 210 and the second receiving element 220 can receive an electromagnetic wave.

The transmitter 100 can emit electromagnetic waves, in particular light or radio waves. When the transmitter 100 emits light, the sensor device 10 can function as a LiDAR (Light Detection And Ranging), and when the sensor device 10 emits a radio wave, the sensor device 10 may be an RADAR (RAdio Detection And Ranging). Can function as The transmitter 100 can be, for example, a laser light source, in particular a laser diode (LD).

Each of the first receiving element 210 and the second receiving element 220 can receive the electromagnetic wave emitted from the transmitter 100 and reflected from the object O. Each of the first receiving element 210 and the second receiving element 220 can be, for example, a light receiving element, in particular, an avalanche photodiode (APD).

The movable reflector 300 can be periodically rocked, and in particular, the swing angle of the movable reflector 300 may change sinusoidally. The angular velocity of the deflection angle of the movable reflector 300 is somewhat high. Specifically, after the movable reflector 300 reflects the electromagnetic wave toward the object O, the electromagnetic wave reflected from the object O is movablely reflected. The deflection angle θ of the movable reflector 300 is changed until the reflector 300 is reflected. The movable reflector 300 can be, for example, a MEMS (Micro Electro Mechanical Systems) mirror.

The sensor device 10 can measure the distance from the sensor device 10 to the object O based on the time required for the electromagnetic wave to be emitted from the transmitter 100 and to be received by the receiver 200. In the following, the time required for the electromagnetic wave to be reflected by the movable reflector 300 after the electromagnetic wave is emitted from the transmitter 100 (FIG. 1) and from the electromagnetic wave being reflected by the movable reflector 300 to reach the receiver 200 The time required (FIGS. 2 and 3) is both very short and considered zero.

FIG. 1 shows an example in which the electromagnetic wave emitted from the transmitter 100 is reflected by the movable reflector 300 at a timing of zero per swing angle θ of the movable reflector 300.

FIG. 2 shows an example where the movable reflector 300 is rotated clockwise in the figure after the timing of FIG. The object O is at a relatively large distance from the sensor device 10 (that is, the time required for the electromagnetic wave to be returned to the sensor device 10 after the electromagnetic wave is emitted from the sensor device 10 is somewhat long). The deflection angle θ of the movable reflector 300 of the sensor device 10 from the time when it is reflected towards the object O by (FIG. 1) and when it is reflected by the movable reflector 300 towards the receiver 200 (FIG. 2) , Has changed from zero to + α. Thus, the movable reflector 300 can reflect the electromagnetic wave emitted from the transmitter 100 toward the object O in one direction (FIG. 1), and reflects the electromagnetic wave reflected from the object O , It is possible to reflect in a direction different from the one direction (FIG. 2).

FIG. 3 shows an example where the movable reflector 300 is rotated counterclockwise in the figure after the timing of FIG. The object O is at a relatively large distance from the sensor device 10 (that is, the time required for the electromagnetic wave to be returned to the sensor device 10 after the electromagnetic wave is emitted from the sensor device 10 is somewhat long). The deflection angle θ of the movable reflector 300 of the sensor device 10 from the time when it is reflected towards the object O by (FIG. 1) and when it is reflected by the movable reflector 300 towards the receiver 200 (FIG. 3) , Has changed from zero to -α. Thus, the movable reflector 300 can reflect the electromagnetic wave emitted from the transmitter 100 toward the object O in one direction (FIG. 1), and reflects the electromagnetic wave reflected from the object O , It is possible to reflect in a direction different from the one direction (FIG. 3).

The receiver 200 includes a first receiving element 210 (first receiving unit) and a second receiving element 220 (second receiving unit), and the first receiving element 210 and the second receiving element 220 are virtual in the figure. They are offset from axis A in opposite directions. In particular, in the examples shown in FIGS. 1 to 3, the first receiving element 210 and the second receiving element 220 are disposed at mutually opposing positions with the virtual axis A in between. The virtual axis A is an axis through which the electromagnetic wave reflected by the movable object 300 reflected from the object O and directed to the one direction (the direction in which the movable reflector 300 is directed at the timing in FIG. 1) can pass. .

According to the configuration described above, even when the object O is separated from the sensor device 10 by a certain distance, it is possible to widen the range in which the receiver 200 can receive the electromagnetic wave. Specifically, as shown in FIGS. 1 and 2, when the movable reflector 300 is rotated clockwise in the figure, as shown in FIG. 2, the electromagnetic wave reflected by the movable reflector 300 is subjected to the first reception. It can be received by the element 210, ie a receiver offset from the virtual axis A to one side. On the other hand, when the movable reflector 300 rotates counterclockwise in the figure as shown in FIGS. 1 and 3, the electromagnetic wave reflected by the movable reflector 300 is received by the first receiving element 210. I can not However, as shown in FIG. 3, the electromagnetic wave reflected by the movable reflector 300 can be received by the second receiving element 220, that is, a receiving unit shifted from the virtual axis A to the other side. In this way, it is possible to widen the range in which the receiver 200 can receive an electromagnetic wave.

Although the virtual axis A in the example shown in FIGS. 1 to 3 is an axis through which the electromagnetic wave reflected by the movable reflector 300 at a shake angle θ of zero can pass, the virtual axis A is a shake angle θ May be an axis through which the electromagnetic wave reflected by the movable reflector 300 at an angle other than zero can pass.

FIG. 4 is a diagram for explaining an example of the function of the sensor device 10 shown in FIGS. 1 to 3. The shake angle θ in FIG. 4 indicates the shake angle θ of the movable reflector 300 in FIGS. 1 to 3, and the plot on the curve showing the shake angle θ in FIG. 4 is an electromagnetic wave emitted from the transmitter 100. The timing reflected by the movable reflector 300 is shown.

The curve representing the swing angle θ can be divided into two phases P1 and P2. In the phase P1, the swing angle θ monotonously increases (that is, the derivative θ ′ (t) of the swing angle θ is positive). On the other hand, at the phase P2, the shake angle θ monotonously decreases (that is, the derivative θ ′ (t) of the shake angle θ is negative).

The electromagnetic wave reflected towards the object O by the movable reflector 300 in the phase P1 can be received by the first receiving element 210, as shown in FIG.

The electromagnetic wave reflected towards the object O by the movable reflector 300 at the phase P2 can be received by the second receiving element 220, as shown in FIG.

The receiver 200 can receive electromagnetic waves in a wide range, ie, both of the phases P1 and P2. Specifically, if the receiver 200 includes only the first receiving element 210 of the first receiving element 210 and the second receiving element 220, it is reflected toward the object O by the movable reflector 300 in phase P1. Even if the electromagnetic wave can be received by the first receiving element 210, the electromagnetic wave reflected toward the object O by the movable reflector 300 in the phase P2 can not be received by the first receiving element 210. Similarly, if the receiver 200 includes only the second receiving element 220 among the first receiving element 210 and the second receiving element 220, the light is reflected toward the object O by the movable reflector 300 at phase P2. Although the electromagnetic wave can be received by the second receiving element 220, the electromagnetic wave reflected toward the object O by the movable reflector 300 in the phase P1 can not be received by the second receiving element 220. On the other hand, when the receiver 200 includes both the first receiving element 210 and the second receiving element 220, the receiver 200 can receive electromagnetic waves in both phases P1 and P2.

FIGS. 5 to 7 are diagrams for explaining the relationship between the resonance frequency f ₀ of the movable reflector 300 and the function of the sensor device 10.

In the sensor device 10 shown in FIGS. 1 to 3, the resonance frequency f ₀ of the movable reflector 300 can be reduced, as will be described in detail with reference to FIGS. 5 to 7. As the resonance frequency f ₀ decreases, the amplitude A of the movable reflector 300 (that is, the FOV (Field Of View) of the sensor device 10) can be increased, and the measurable distance range L of the sensor device 10 is widened. Thus, the measurable distance of the sensor device 10 can be increased.

The reason why the resonant frequency f ₀ of the movable reflector 300 can be reduced in the sensor device 10 shown in FIGS. 1 to 3 will be described using FIG. 5. FIG. 5 shows the arrangement of pixels in one frame. In FIG. 5, the sensor device 10 performs raster scanning, and in particular, the electromagnetic waves reflected by the movable reflector 300 are applied to the plots in FIG. 5 along the curves in FIG. There is.

The resonant frequency f ₀ of the movable reflector 300 is as shown in the following equation (1).

Here, p indicates the pitch of the scan, and R _f indicates the frame rate.

The number n in equation (1) indicates the number of lines scanned while the movable reflector 300 oscillates once. The number n is 1 when scanning is performed in only one of the oscillations of the movable reflector 300, as shown in FIG. On the other hand, the number n is 2 if scanning is performed in both directions of the vibration of the movable reflector 300 as shown in FIG.

As apparent from the equation (1), by performing scanning in both directions of the vibration of the movable reflector 300, the resonance frequency f ₀ can be reduced.

Next, the relationship between the resonance frequency f ₀ of the movable reflector 300 and the amplitude A of the movable reflector 300 (that is, the FOV of the sensor device 10) will be described using FIG.

The swing angle θ of the movable reflector 300 is as shown in the following equation (2).

However, A shows the amplitude of the movable reflector 300.

The maximum value F _{max of the} force acting on the movable reflector 300 is as shown in the following equation (3), and must be equal to or less than the allowable value F _acc .

Here, m represents the mass of the movable reflector 300.

As is apparent from equation (3), by reducing the resonant frequency _{f 0,} it is possible to increase the amplitude A of the movable reflector 300 (i.e., FOV of the sensor device 10).

Next, the relationship between the resonant frequency f ₀ of the movable reflector 300 and the measurable distance range L of the sensor device 10 will be described using FIG. 7.

The relationship between the swing angle Δθ of the movable reflector 300 and the diameter D _APD of the first receiving element 210 is as shown in the following equation (4).

However, S indicates the sensitivity of the movable reflector 300.

The time Δt required for the movable reflector 300 to rotate the swing angle Δθ is as shown in the following equation (5).

The measurable distance range L of the sensor device 10 is cΔt / 2 (c: speed of light), and is expressed by the following equation (6).

As apparent from the equation (6), the measurable distance range L of the sensor device 10 becomes wider as the resonance frequency f ₀ becomes smaller.

Next, the relationship between the resonant frequency f ₀ of the movable reflector 300 and the longest measurable distance of the sensor device 10 will be described.

The power of the electromagnetic wave reflected toward the object O by the movable reflector 300 is determined by the transmission interval Δt _min of the electromagnetic wave from the viewpoint of eye safety. The transmission interval Δt _{min of the} electromagnetic wave is expressed by the following equation (7), and the power of the electromagnetic wave can be increased as the transmission interval Δt _min is longer.

As apparent from the equation (7), the power of the electromagnetic wave reflected by the movable reflector 300 toward the object O (corresponding to the farthest measurable distance of the sensor device 10) is the resonant frequency of the movable reflector As f ₀ is smaller, it can be larger.

The power that can be received by the first receiving element 210 for the electromagnetic wave reflected from the object O is as shown in the following equation (8).

However, ρ indicates the surface density of the material of the movable reflector 300, E indicates the area of the movable reflector 300, and m = ρE.

As apparent from the equation (8), the power (corresponding to the longest measurable distance of the sensor device 10) that can be received by the first receiving element 210 for the electromagnetic wave reflected from the object O The smaller the resonance frequency f _{0, the} larger the frequency.

FIG. 8 is a diagram for explaining an example of the function of the sensor device 10 shown in FIGS. 1 to 3.

As described with reference to FIG. 4, in the sensor device 10 shown in FIGS. 1 to 3, the electromagnetic wave is reflected toward the object O by the movable reflector 300 in both directions of the vibration of the movable reflector 300. (The lower graph in Figure 8). Furthermore, in the sensor device 10 shown in FIG. 1 to FIG. 3, one of the vibrations of the movable reflector 300 is achieved by halving the transmission interval of the electromagnetic waves while keeping the resonance frequency f ₀ constant. Only in direction can electromagnetic waves be reflected by the movable reflector 300 towards the object O (upper graph in FIG. 8).

FIG. 9 is a diagram for explaining a first example of the details of the receiver 200. As shown in FIG.

The receiver 200 includes a first receiving element 210, a second receiving element 220, and a differential amplifier 230. The signal Vin + from the first receiving element 210 is input to the non-inverting input terminal (+) of the differential amplifier 230, and the signal from the second receiving element 220 is input to the inverting input terminal (-) of the differential amplifier 230. Vin- is input. The differential amplifier 230 outputs a difference Vout between the signal Vin + and the signal Vin−.

In this configuration, even if a noise signal (for example, clock noise) is generated from the first receiving element 210 and the second receiving element 220 when the first receiving element 210 and the second receiving element 220 do not receive an electromagnetic wave. The noise signal is canceled in the signal Vout output from the differential amplifier 230, and the noise signal is removed.

FIG. 10 is a diagram for explaining a second example of the details of the receiver 200. As shown in FIG.

The receiver 200 includes a first receiving element 210, a second receiving element 220, and an integrating circuit 240.

In FIG. 10A, the difference between the output signal of the second receiving element 220 and the target value r is input to the integrating circuit 240, and the output signal of the integrating circuit 240 is input to the first receiving element 210. An output signal of the element 210 is output to the outside of the receiver 200. Therefore, it is possible to optimize the first receiving element 210 based on the output signal of the integrating circuit 240 (especially, adjust the gain of the first receiving element 210 when the first receiving element 210 is an APD). . In particular, at timing when the first receiving element 210 receives an electromagnetic wave reflected from the object O (for example, the phase P1 in FIG. 4), the receiver 200 can function as shown in FIG. . That is, the receiving unit (first receiving element 210) for receiving the electromagnetic wave reflected from the object O using the output signal of the receiving unit (second receiving element 220) not receiving the electromagnetic wave reflected from the object O It can be optimized.

In FIG. 10B, the difference between the output signal of the first receiving element 210 and the target value r is input to the integrating circuit 240, and the output signal of the integrating circuit 240 is input to the second receiving element 220. An output signal of the element 220 is output to the outside of the receiver 200. Therefore, it is possible to optimize the second receiving element 220 based on the output signal of the integration circuit 240 (especially, adjust the gain of the second receiving element 220 when the second receiving element 220 is an APD). . In particular, at timing when the second receiving element 220 receives an electromagnetic wave reflected from the object O (for example, phase P1 in FIG. 4), the receiver 200 can function as shown in FIG. . That is, using the output signal of the receiving unit (first receiving element 210) that does not receive the electromagnetic wave reflected from the object O, the receiving unit (second receiving element 220) that receives the electromagnetic wave reflected from the object O It can be optimized.

In the configuration described above, the first receiving element 210 and the second receiving element 220 can be optimized based on the surrounding environment of the receiver 200. In particular, when the first receiving element 210 and the second receiving element 220 can receive background noise (for example, sunlight), the first receiving element 210 and the second receiving element 220 are optimized based on the background noise. Can be

FIG. 11 is a diagram for explaining a third example of the details of the receiver 200. As shown in FIG.

The receiver 200 comprises a first receiving element 210, a second receiving element 220 and a controller 250. The controller 250 operates only one or both of the first receiving element 210 and the second receiving element 220 based on the state of the first receiving element 210 and the state of the second receiving element 220.

In the first example of the controller 250, when an abnormality (for example, an error or a failure) is detected in one of the first reception element 210 and the second reception element 220, the controller 250 operates the operation of the reception element having the abnormality. May be stopped to operate only the normal receiving element. Even in this case, the sensor device 10 can function only with the receiving element without any abnormality.

In the second example of the controller 250, the controller 250 operates only one or both of the first reception element 210 and the second reception element 220 according to the specification (for example, resolution) required of the sensor device 10. You may do so. In particular, when the resolution required for the sensor device 10 is high, the controller 250 can cause both the first receiving element 210 and the second receiving element 220 to operate, and the resolution required for the sensor device 10 When low, the controller 250 may cause only one of the first receiving element 210 and the second receiving element 220 to operate. By operating only one of the first reception element 210 and the second reception element 220, power consumption of the sensor device 10 can be suppressed.

In the third example of the controller 250, depending on the internal temperature of the sensor device 10 or the ambient temperature, the controller 250 may operate only one or both of the first reception element 210 and the second reception element 220. Good. In particular, when the internal temperature or ambient temperature of the sensor device 10 is low, the controller 250 can cause both the first receiving element 210 and the second receiving element 220 to operate, and the internal temperature of the sensor device 10 or When the ambient temperature is high, the controller 250 may cause only one of the first receiving element 210 and the second receiving element 220 to operate. By operating only one of the first receiving element 210 and the second receiving element 220, heat generation from the sensor device 10 can be suppressed, and the sensor device 10 operates even if the internal temperature or ambient temperature of the sensor device 10 is high. It can be done.

As described above, according to the present embodiment, it is possible to widen the range in which the receiver 200 can receive an electromagnetic wave even if the object O is separated from the sensor device 10 by a certain distance.

Second Embodiment
12, 13 and 14 are views for explaining the sensor device 10 according to the second embodiment, and correspond to FIGS. 1, 2 and 3 of the first embodiment, respectively. The sensor device 10 according to the present embodiment is the same as the sensor device 10 according to the first embodiment except for the following points.

The sensor device 10 includes a shielding member 600. The shielding member 600 separates the movable reflector 300 from the receiver 200. The shielding member 600 has a first stop 610 and a second stop 620, and the first stop 610 and the second stop 620 are located on opposite sides of the imaginary axis A. A part (first receiver) of the receiver 200 can receive the electromagnetic wave that has passed through the first diaphragm 610, and another part (second receiver) of the receiver 200 can receive the second electromagnetic wave. The electromagnetic waves having passed through the aperture 620 can be received.

When the movable reflector 300 is rotated clockwise in the drawing as shown in FIGS. 12 and 13, the electromagnetic wave reflected by the movable reflector 300 is the first stop 610, that is, the virtual, as shown in FIG. It passes through an aperture which is offset from axis A to one side and is received by a part (first receiver) of the receiver 200.

When the movable reflector 300 is rotated counterclockwise in the drawing as shown in FIGS. 12 and 14, the electromagnetic wave reflected by the movable reflector 300 is second diaphragm 620, ie, as shown in FIG. It passes through the diaphragm, which is offset from the virtual axis A to the other side, and is received by the other part of the receiver 200 (second receiver).

According to this embodiment, as in the first embodiment, even when the object O is separated from the sensor device 10 by a large distance to some extent, it is possible to widen the range in which the receiver 200 can receive the electromagnetic wave.

(Embodiment 3)
15, 16 and 17 are diagrams for explaining the sensor device 10 according to the third embodiment, and correspond to FIGS. 1, 2 and 3 of the first embodiment, respectively. The sensor device 10 according to the present embodiment is the same as the sensor device 10 according to the first embodiment except for the following points.

The sensor device 10 comprises a receiver 200 and a reflector 700. The receiver 200 is offset from virtual axis A to one side, and the reflector 700 is offset from virtual axis A to the other side. In particular, in the examples shown in FIGS. 15 to 17, the receiver 200 and the reflector 700 are disposed at mutually opposing positions with the imaginary axis A in between.

When the movable reflector 300 rotates clockwise in the drawing as shown in FIGS. 15 and 16, the electromagnetic wave reflected by the movable reflector 300 is reflected by the reflector 700, ie, the imaginary axis, as shown in FIG. It is incident on an optical element shifted from A to one side, reflected by the reflector 700 towards the receiver 200 and received by the receiver 200. That is, the receiver 200 can receive the electromagnetic wave reflected by the reflector 700 from the movable reflector 300.

When the movable reflector 300 rotates counterclockwise in the figure as shown in FIGS. 15 and 17, the electromagnetic wave reflected by the movable reflector 300 is a receiver 200, ie, a virtual, as shown in FIG. It is incident on an optical element offset from the axis A to the other side and received by the receiver 200. That is, the receiver 200 can receive the electromagnetic wave reflected by the movable reflector 300 from the movable reflector 300.

(Embodiment 4)
18, 19 and 20 are views for explaining the sensor device 10 according to the fourth embodiment, and correspond to FIG. 1, FIG. 2 and FIG. 3 of the first embodiment, respectively. The sensor device 10 according to the present embodiment is the same as the sensor device 10 according to the first embodiment except for the following points.

The sensor device 10 comprises a first reflector 710 and a second reflector 720. The first reflector 710 is offset to one side from the imaginary axis A, and the second reflector 720 is offset to the other side from the imaginary axis A. In particular, in the example shown in FIGS. 18 to 20, the first reflector 710 and the second reflector 720 are disposed at mutually opposing positions with the imaginary axis A in between.

When the movable reflector 300 rotates clockwise in the drawing as shown in FIGS. 18 and 19, the electromagnetic wave reflected by the movable reflector 300 is the first reflector 710, ie, as shown in FIG. It is reflected by a reflector that is offset from virtual axis A to one side and received by receiver 200.

When the movable reflector 300 rotates counterclockwise in the drawing as shown in FIGS. 18 and 20, the electromagnetic wave reflected by the movable reflector 300 is a second reflector 720, ie, as shown in FIG. , Reflected by the reflector offset from the virtual axis A to the other side and received by the receiver 200.

21 to 25 are views for explaining the sensor device 10 according to the embodiment.

The sensor device 10 comprises a transmitter 100 and a receiver 200. In the figure, the sensor device 10 is placed at the origin of XY coordinates.

The transmitter 100 can emit an electromagnetic wave in the direction TD. The direction TD is rockable with respect to the origin of XY coordinates. The direction TD may depend, in particular, on embodiment 1 (FIGS. 1 to 3), embodiment 2 (FIGS. 12 to 14), embodiment 3 (FIGS. 15 to 17) and embodiment 4 (FIG. 18) according to various methods. In FIG. 20), the movable reflector 300 enables rocking.

The receiver 200 can receive electromagnetic waves from two directions, direction RD1 and direction RD2. The direction RD1 and the direction RD2 are mutually offset from the direction TD, and interlocking with the direction TD, the direction RD1 and the direction RD2 can swing with respect to the origin of the XY coordinates. Direction RD1 and direction RD2 depend in particular on the various embodiments, embodiment 1 (FIGS. 1 to 3), embodiment 2 (FIGS. 12 to 14), embodiment 3 (FIGS. 15 to 17) and embodiment 4 In FIGS. 18 to 20, the movable reflector 300 is capable of rocking, and electromagnetic waves from two directions can be transmitted by various methods, particularly in the first embodiment (FIGS. 1 to 3). In the second embodiment (FIGS. 12 to 14) by the first receiving element 210 and the second receiving element 220, the third embodiment (FIGS. 15 to 17) by the first diaphragm 610 and the second diaphragm 620 of the shielding member 600. Receiver 200 and reflector 700 enable embodiment 4 (FIGS. 18-20) to be received by first reflector 710 and second reflector 720.

FIG. 21 shows an example in which an electromagnetic wave is emitted from the transmitter 100 toward the object O at time t = 0. At the timing of FIG. 21, the direction TD is along the Y direction.

22 and 23 show an example in which the direction TD, the direction RD1, and the direction RD2 rotate clockwise in the drawing after the timing of FIG. 22, the electromagnetic wave emitted from the transmitter 100 (in the figure, the electromagnetic wave is indicated by an arrow) reaches the object O at time t = Δt, and in FIG. 23, the electromagnetic wave reflected from the object O ( In the figure, an electromagnetic wave is shown by an arrow.) Reaches the receiver 200 at time t = 2Δt.

FIGS. 24 and 25 show an example in which the direction TD, the direction RD1, and the direction RD2 rotate counterclockwise in the drawing after the timing of FIG. In FIG. 24, the electromagnetic wave emitted from the transmitter 100 (in the figure, the electromagnetic wave is indicated by the arrow) reaches the object O at time t = Δt, and in FIG. 25 the electromagnetic wave reflected from the object O ( In the figure, an electromagnetic wave is shown by an arrow.) Reaches the receiver 200 at time t = 2Δt.

At timing (first timing) in FIG. 23, the receiver 200 directs the direction RD1 to the object O, and receives the electromagnetic wave reflected from the object O.

At timing (second timing) in FIG. 25, the receiver 200 directs the direction RD2 to the object O, and receives the electromagnetic wave reflected from the object O.

According to the configuration described above, even when the object O is separated from the sensor device 10 by a certain distance, it is possible to widen the range in which the receiver 200 can receive the electromagnetic wave. Specifically, as shown in FIG. 21, FIG. 22 and FIG. 23, when the movable reflector 300 rotates clockwise in the figure, as shown in FIG. 23, the electromagnetic wave reflected from the object O has a direction RD1 can be received by receiver 200 from a direction that is offset to one side of direction TD. On the other hand, when the movable reflector 300 rotates counterclockwise in the figure as shown in FIGS. 21, 24 and 25, the electromagnetic wave reflected from the object O is received by the receiver 200 from the direction RD1. I can not receive. However, as shown in FIG. 25, the electromagnetic wave reflected from the object O can be received by the receiver 200 from the direction RD2, that is, the direction shifted from the direction TD to the other side. In this way, it is possible to widen the range in which the receiver 200 can receive an electromagnetic wave.

As mentioned above, although an embodiment and an example were described with reference to drawings, these are the illustrations of the present invention and can also adopt various composition except the above.

This application claims priority based on Japanese Patent Application No. 2017-139681 filed on Jul. 19, 2017, the entire disclosure of which is incorporated herein.

Claims

A transmitter,
A receiver,
The movable electromagnetic wave emitted from the transmitter can be reflected in one direction toward an object, and the electromagnetic wave reflected from the object can be reflected in a direction different from the one direction. A reflector,
Equipped with
The receiver is disposed at a position opposite to each other across an imaginary axis through which an electromagnetic wave reflected from the object and reflected by the movable reflector facing the one direction can pass. A sensor device comprising a unit and a second receiving unit.
In the sensor device according to claim 1,
A blocking member having a first aperture and a second aperture;
The first receiving unit is capable of receiving the electromagnetic wave that has passed through the first aperture of the blocking member,
The sensor device capable of receiving the electromagnetic wave that has passed through the second diaphragm of the blocking member.
In the sensor device according to claim 1 or 2,
A sensor device in which the swing angle of the movable reflector changes in a sinusoidal manner.
A transmitter that emits an electromagnetic wave,
An electromagnetic wave emitted from the transmitter can be reflected in one direction toward an object, and a movable reflection capable of reflecting the electromagnetic wave reflected from the object in a direction different from the one direction can be reflected. And the
A reflector for reflecting the electromagnetic wave reflected by the object;
A receiver for receiving the electromagnetic wave reflected by the object and the electromagnetic wave reflected by the reflector;
Equipped with
The receiver and the reflector are disposed at mutually opposing positions with an imaginary axis through which an electromagnetic wave reflected from the object and reflected by the movable reflector facing the one direction can pass. Sensor device.
A transmitter,
A receiver,
A first reflector,
A second reflector,
The movable electromagnetic wave emitted from the transmitter can be reflected in one direction toward an object, and the electromagnetic wave reflected from the object can be reflected in a direction different from the one direction. A reflector,
Equipped with
The first reflector and the second reflector are opposed to each other across an imaginary axis through which the electromagnetic wave reflected from the object and reflected by the movable reflector facing the one direction can pass. Are located in
The sensor device, wherein the receiver can receive the electromagnetic wave reflected by the first reflector and the second reflector from the movable reflector.
A transmitter capable of emitting an electromagnetic wave in one direction,
A receiver capable of receiving electromagnetic waves from two directions shifted from the one direction to the other side;
Equipped with
At the first timing, the receiver directs one of the two directions to an object, and receives an electromagnetic wave emitted from the transmitter and reflected from the object,
In the second timing, the receiver directs the other of the two directions to the object and receives an electromagnetic wave emitted from the transmitter and reflected from the object.
A transmitter, a receiver, and a movable reflector are prepared, and an electromagnetic wave emitted from the transmitter is reflected toward the object by the movable reflector, and is reflected from the object to be reflected by the movable reflector. Receiving by the receiver the electromagnetic wave reflected by
The movable reflector can reflect the electromagnetic wave emitted from the transmitter in one direction toward the object, and can reflect the electromagnetic wave reflected from the object in a direction different from the one direction. Facing and reflecting,
The receiver is disposed at a position opposite to each other across an imaginary axis through which an electromagnetic wave reflected from the object and reflected by the movable reflector facing the one direction can pass. A sensing method, comprising: a unit and a second receiver.
A transmitter, a receiver, a reflector, and a movable reflector are provided, and an electromagnetic wave emitted from the transmitter is reflected by the movable reflector toward the object, and is reflected from the object. Receiving the electromagnetic wave reflected by the movable reflector by the receiver;
The movable reflector can reflect the electromagnetic wave emitted from the transmitter in one direction toward the object, and can reflect the electromagnetic wave reflected from the object in a direction different from the one direction. Facing and reflecting,
The receiver and the reflector are disposed at mutually opposing positions with an imaginary axis through which an electromagnetic wave reflected from the object and reflected by the movable reflector facing the one direction can pass. Yes,
The sensing method is capable of receiving the electromagnetic wave reflected by the movable reflector from the movable reflector and the electromagnetic wave reflected by the reflector from the movable reflector.
A transmitter, a receiver, a first reflector, a second reflector, and a movable reflector are provided, and an electromagnetic wave emitted from the transmitter is reflected toward the object by the movable reflector. Receiving by the receiver the electromagnetic waves reflected from the object and reflected by the movable reflector,
The movable reflector can reflect the electromagnetic wave emitted from the transmitter toward the one direction toward the object, and the electromagnetic wave reflected from the object may face the direction different from the one direction. Can be reflected,
The first reflector and the second reflector are opposed to each other across an imaginary axis through which the electromagnetic wave reflected from the object and reflected by the movable reflector facing the one direction can pass. Are located in
The sensing method may be such that the receiver can receive the electromagnetic wave reflected by the first reflector and the second reflector from the movable reflector.
Preparing a transmitter and a receiver, emitting an electromagnetic wave from the transmitter to an object, and receiving the electromagnetic wave reflected from the object by the receiver;
The transmitter can emit the electromagnetic wave in one direction,
The receiver can receive electromagnetic waves from two directions shifted from the one direction to the opposite side,
At the first timing, the receiver directs one of the two directions to an object, and receives an electromagnetic wave emitted from the transmitter and reflected from the object,
In the second timing, the receiver directs the other of the two directions to the object, and receives an electromagnetic wave emitted from the transmitter and reflected from the object.