WO2019172166A1

WO2019172166A1 - Scanning device and distance measuring device

Info

Publication number: WO2019172166A1
Application number: PCT/JP2019/008322
Authority: WO
Inventors: 孝典落合; 佐藤　充; 柳澤　琢麿; 小笠原　昌和; 亮出田
Original assignee: パイオニア株式会社
Priority date: 2018-03-05
Filing date: 2019-03-04
Publication date: 2019-09-12

Abstract

This scanning device comprises: a light source unit; a first filter which transmits only light in a partial wavelength band, among emitted light from the light source unit, as first transmitted light; a deflecting unit which projects the first transmitted light toward a prescribed region as scanned light; a second filter which transmits, as second transmitted light, light in a wavelength band overlapping the wavelength band of the first transmitted light, among reflected light obtained by the scanned light being reflected by a target object in the prescribed region; and a receiving unit which receives the second transmitted light.

Description

Scanning device and distance measuring device

The present invention relates to a scanning device that performs optical scanning and a ranging device that performs optical ranging.

2. Description of the Related Art Conventionally, distance measuring devices that measure the distance to an object by irradiating the object with light and detecting the light reflected by the object are known. There is also known an optical scanning type distance measuring device that performs optical scanning of an object and obtains information related to the shape and orientation of the object in addition to the distance to the object.

For example, the scanning type distance measuring device includes, as a scanning device, a MEMS (Micro Electro Mechanical Systems) mirror, a light source that emits light toward the mirror, and a light receiving unit that receives reflected light from an object. Have. For example, Patent Document 1 discloses a distance measuring unit that measures a distance to an object to be measured based on an elapsed time from when light is emitted from a light projecting unit to when reflected light is received by a light receiving unit, An optical radar device is disclosed that includes a bandpass filter that guides light of a certain wavelength to a light receiving unit.

JP 2007-85832 A

A scanning distance measuring device projects, for example, a pulsed laser beam toward a scanning region, and receives and detects reflected light (light pulse) from an object, thereby optically detecting in the scanning region. Get information. Considering that accurate scanning information (light information) is obtained, the light received by the device has little noise light, for example, light that is not caused by light emitted from the device such as ambient light is reflected in the reflected light. On the other hand, a small amount is preferable. Therefore, for example, it is conceivable to use high output light for scanning.

On the other hand, for example, when a scanning device or a distance measuring device is mounted on a moving body, for example, it is required to satisfy the safety standards for laser products defined in JIS C 6802 / IEC 60825-1. Thus, even when the light output from the apparatus is increased in order to obtain an optical signal with a small noise component, there may be a restriction condition on the amount of light that can be emitted, for example.

Also, the characteristics of a light source that generates light emitted from the apparatus often change depending on the usage environment (for example, temperature, humidity, usage time, etc.). Therefore, for example, even when a part of the received optical signal is removed by a filter, not only the noise component but also the signal component (pulse component) may be removed, or the noise component may not be sufficiently removed.

The present invention has been made in view of the above points, and projects an appropriate amount of light onto an object and appropriately removes a noise component of the received light so that accurate light within a scanning region can be obtained. An object is to provide a scanning device and a distance measuring device capable of performing scanning.

The invention according to claim 1 is a light source unit, a first filter that transmits only a part of the wavelength band of light emitted from the light source unit as the first transmitted light, and the first transmitted light. Of the wavelength region that overlaps the wavelength region of the first transmitted light among the reflected light reflected by the object in the predetermined region It has the 2nd filter which permeate | transmits light as 2nd transmitted light, and the light-receiving part which light-receives 2nd transmitted light, It is characterized by the above-mentioned.

The invention according to claim 9 includes the scanning device according to claim 1, and a distance measuring unit that measures the distance to the object based on the result of receiving the second transmitted light by the light receiving unit. It is characterized by that.

According to a tenth aspect of the present invention, there is provided a light source unit, a deflecting unit for projecting light emitted from the light source unit toward a predetermined region while deflecting light emitted from the light source unit in a variable direction, and the scanning light in a predetermined region. And a light receiving unit that receives reflected light reflected by the object inside, and a filter provided on the optical path of the emitted light and on the optical path of the reflected light.

FIG. 3 is a diagram illustrating an arrangement example of distance measuring apparatuses according to the first embodiment. 1 is a diagram illustrating a configuration example of a scanning device in a distance measuring device according to Embodiment 1. FIG. It is a figure which shows the example of a characteristic of the emitted light from the light source part in the ranging apparatus which concerns on Example 1. FIG. FIG. 6 is a diagram illustrating an example of characteristics of light transmitted through a first filter in the distance measuring apparatus according to the first embodiment. It is a figure which shows the example of a characteristic of the light which the ranging apparatus which concerns on Example 1 light-receives. It is a figure which shows the characteristic of the light which permeate | transmitted the 2nd filter in the ranging apparatus which concerns on Example 1. FIG. It is a figure which shows the example of a characteristic of the emitted light from the light source part in the ranging apparatus which concerns on Example 1. FIG. FIG. 6 is a diagram illustrating an example of characteristics of light transmitted through a first filter in the distance measuring apparatus according to the first embodiment. It is a figure which shows the example of a characteristic of the light which the ranging apparatus which concerns on Example 1 light-receives. It is a figure which shows the characteristic of the light which permeate | transmitted the 2nd filter in the ranging apparatus which concerns on Example 1. FIG. It is a figure which shows the example of a characteristic of the emitted light from the light source part in the ranging apparatus which concerns on Example 1. FIG. FIG. 6 is a diagram illustrating an example of characteristics of light transmitted through a first filter in the distance measuring apparatus according to the first embodiment. It is a figure which shows the example of a characteristic of the emitted light from the light source part in the ranging apparatus which concerns on Example 1. FIG. 6 is a top view of a deflecting unit in the distance measuring apparatus according to Embodiment 1. FIG. 3 is a cross-sectional view of a deflection unit in the distance measuring apparatus according to Embodiment 1. FIG. It is a figure which shows the structural example of the scanning apparatus in the ranging apparatus which concerns on the modification of Example 1. FIG. FIG. 10 is a diagram illustrating an arrangement example of distance measuring apparatuses according to a second embodiment. It is a figure which shows the example of a characteristic of the emitted light from the light source part in the ranging apparatus which concerns on Example 2. FIG. FIG. 10 is a diagram illustrating an example of characteristics of light transmitted through a first filter in the distance measuring apparatus according to the second embodiment. It is a figure which shows the example of a characteristic of the light which the ranging device which concerns on Example 2 receives. It is a figure which shows the characteristic of the light which permeate | transmitted the 2nd filter in the ranging apparatus which concerns on Example 2. FIG.

Hereinafter, embodiments of the present invention will be described in detail.

FIG. 1 is a schematic layout diagram of the distance measuring apparatus 10 according to the first embodiment. The distance measuring device 10 is a scanning distance measuring device that performs optical scanning of a predetermined region (hereinafter referred to as a scanning region) R0 and measures the distance to the object OB existing in the scanning region R0. The distance measuring device 10 will be described with reference to FIG. For clarity of illustration, FIG. 1 schematically shows the scanning region R0 and the object OB.

First, the distance measuring device 10 includes a light source unit 11 that generates and emits pulsed light (hereinafter referred to as emission light) L1. In the present embodiment, the light source unit 11 generates pulsed laser light having a peak wavelength in the infrared region as the emitted light L1.

The distance measuring device 10 includes a filter (hereinafter referred to as a first filter) 12 that transmits a part of the wavelength range of the outgoing light L1 from the light source unit 11 as the first transmitted light L11. In the present embodiment, the first filter 12 is a variable wavelength band-pass filter capable of changing the transmission wavelength region (the wavelength region of the first transmitted light L11 in the present embodiment).

For example, the first filter 12 has a pair of reflective films (not shown) that face each other and whose facing interval changes. The pair of reflective films constitutes a Fabry-Perot etalon. The 1st filter 12 permeate | transmits the light of the wavelength range according to the space | interval of the said pair of reflective film as the 1st transmitted light L11.

The distance measuring device 10 includes a light projecting unit 13 that projects the first transmitted light L11 toward the scanning region R0 as the scanning light (light projection signal) L2. In the present embodiment, the light projecting unit 13 is a deflecting unit that generates the scanning light L2 by changing the emission direction of the first transmitted light L11 and projects the scanning light L2 toward the scanning region R0. is there. Hereinafter, a case where the distance measuring device 10 includes a deflecting unit as the light projecting unit 13 will be described.

In this embodiment, the deflecting unit 13 includes a movable mirror having a movable light reflecting surface 13A that reflects the first transmitted light L11 toward the scanning region R0. The deflecting unit 13 changes the direction in which the first transmitted light L11 is reflected continuously and periodically by changing the direction of the light reflecting surface 13A. In this embodiment, the deflecting unit 13 functions as a scanning unit (sweep unit) that scans (sweeps) the scanning region R0 with the scanning light L2. The scanning region R0 is a virtual three-dimensional space having a width and a height corresponding to the movable range of the light reflecting surface 13A. In FIG. 1, the outer edge of the scanning region R0 is schematically shown by a broken line.

For example, as shown in FIG. 1, when the object OB is present on the optical path of the scanning light L2 in the scanning region R0, the object OB is irradiated with the scanning light L2, and the scanning light L2 is reflected by the object OB ( Scatter).

The distance measuring device 10 includes light (hereinafter, referred to as reflected light) L3 reflected by the object OB when the scanning light L2 is applied to the object OB (light incident on the distance measuring device 10, hereinafter referred to as “light”). A filter (hereinafter referred to as a second filter) 14 that performs filtering on the LS (referred to as incident light) and transmits light in a part of the wavelength band included in the incident light LS as the second transmitted light L31. . In the following, the incident light LS refers to light incident on the second filter 14.

In the present embodiment, the second filter 14 has the same configuration as the first filter 12. In the present embodiment, the second filter 14 is a wavelength-variable type bandpass filter capable of changing the transmission wavelength region (that is, the wavelength region of the second transmitted light L31). However, the 2nd filter 14 should just be comprised so that the light of all or one part wavelength range of the light which permeate | transmits the 1st filter 12 may be permeate | transmitted, The concrete structure is not limited. .

The second filter 14 is configured to transmit, as the second transmitted light L31, light in a wavelength range in which at least a part of the reflected light L3 overlaps the wavelength range of the first transmitted light L11. For example, in the present embodiment, the second filter 14 has the same transmission wavelength range as the first filter 12, or is included in the transmission wavelength range of the first filter 12 and narrower than this. The light transmission characteristic is changed in conjunction with the first filter 12 so as to have

The distance measuring device 10 includes a light receiving unit 15 that receives and detects the second transmitted light L31. For example, the light receiving unit 15 performs photoelectric conversion on the second transmitted light L31 and generates an electrical signal (a signal indicating a scanning result, hereinafter referred to as a scanning information signal) SR according to the second transmitted light L31. To do.

In the present embodiment, the second filter 14 receives the light including the reflected light L3 reflected by the object OB and returned to the deflecting unit 13 as the incident light LS, and the second light 14 is generated from the incident light LS. The transmitted light L31 is generated.

Specifically, in this embodiment, the distance measuring device 10 is provided on the optical path of the first transmitted light L11 between the first filter 12 and the light reflecting surface 13A of the deflecting unit 13, and the deflecting unit 13 includes a light projecting / receiving separation unit BS that guides the incident light LS having passed through 13 to the second filter 14. In the present embodiment, the light projecting / receiving separation unit BS is a beam splitter. Hereinafter, a case where the distance measuring device 10 has a beam splitter as the light projecting / receiving separation unit BS will be described.

In the distance measuring device 10, the first transmitted light L11, which is the emitted light L1 that has passed through the first filter 12, passes through the beam splitter BS and travels toward the deflecting unit 13, and as the scanning light L2, the scanning region R0. Will be flooded.

On the other hand, the scanning light L2 is reflected by the object OB existing in the scanning region R0 to become reflected light L3, and a part thereof returns toward the light reflecting surface 13A of the deflecting unit 13. The reflected light L3 is reflected by the light reflecting surface 13A, then reflected by the beam splitter BS, and enters the second filter 14. Therefore, in this embodiment, the light receiving unit 15 receives the reflected light L3 transmitted through the deflecting unit 13 and the second filter 14 as the second transmitted light L31.

The distance measuring device 10 includes a distance measuring unit 16 that measures the distance to the object OB based on the scanning information signal SR. In the present embodiment, the distance measuring unit 16 detects the pulse of the second transmitted light L31 from the scanning information signal SR, and performs the object OB (or its object) by the time-of-flight method based on the time difference from the emission of the emission light L1. Measure the distance to some surface area. The distance measuring unit 16 generates data (ranging data) indicating the measured distance information.

In this specification, for the sake of explanation, a virtual scanned surface that is a predetermined distance away from the distance measuring device 10 in the scanning region R0 may be referred to as a scanning surface R1. FIG. 1 exemplarily shows the scanning plane R1. Scanning and ranging of the scanning region R0 by the distance measuring device 10 are performed using the scanning light L2 emitted toward the scanning surface R1 with the scanning surface R1 as a target.

In the present embodiment, the distance measuring unit 16 generates data (ranging image data) for imaging the scanning region R0 based on the distance measurement data obtained by the scanning light L2 that is pulsed and projected. . For example, the distance measurement unit 16 has one distance measurement image data for every change period of the light projecting direction of the scanning light L2 by the deflecting unit 13, that is, every period of scanning the scanning region R0 (hereinafter sometimes referred to as a scanning period). Is generated.

The scanning cycle is, for example, in the case where light sweeping is periodically performed on the scanning region R0, from the time of an arbitrary device state (for example, the direction of the light reflecting surface 13A in the deflection unit 13), and then the device state again. The period up to the point of returning to.

In the present embodiment, the distance measurement unit 16 associates the distance measurement data with information indicating the direction of the light reflecting surface 13A, and forms an image as a two-dimensional or three-dimensional map. In the present embodiment, the distance measuring unit 16 generates the map image for each scanning cycle. The distance measuring unit 16 may include a display unit (not shown) that displays a plurality of map images as moving images in time series.

Further, the distance measuring device 10 includes a control unit 17 that performs operation control of the light source unit 11, the first filter 12, the deflecting unit 13, the second filter 14, the light receiving unit 15, and the distance measuring unit 16. For example, in the present embodiment, the control unit 17 supplies a drive signal DL to the light source unit 11 to drive and control the light source unit 11. In addition, the control unit 17 supplies the drive signal DF to the first and

second filters

12 and 14 and controls the transmission wavelength ranges of the first and

second filters

12 and 14. Further, the control unit 17 supplies drive signals DX and DY to the deflecting unit 13 and controls the displacement of the light reflecting surface 13 </ b> A in the deflecting unit 13.

FIG. 2 is a diagram illustrating a detailed configuration example of the distance measuring device 10. First, in the present embodiment, the light source unit 11 includes a light emitting element 11A that generates laser light and a shaping lens 11B that condenses and shapes the laser light. The light emitting element 11A is made of, for example, a semiconductor laser. The light receiving unit 15 includes a condenser lens 15A that receives and collects the second transmitted light L2, and a detection element 15B that detects the collected second transmitted light L2. The detection element 15B includes, for example, at least one photoelectric conversion element.

Next, in this embodiment, the distance measuring device 10 includes a wavelength monitoring unit M1 that monitors the wavelength of the emitted light L1. The wavelength monitoring unit M1 includes, for example, a device (not shown) that detects and stores the spectrum of the emitted light L1 and changes thereof. In the present embodiment, the distance measuring device 10 includes a light amount monitoring unit M2 that monitors the light amount of the first transmitted light L11. The light quantity monitoring unit M2 includes, for example, a device (not shown) that calculates and stores a light quantity (total light quantity) per unit time of the first transmitted light L11.

In this embodiment, as shown in FIG. 2, the outgoing light L1 is separated and guided to the wavelength monitoring unit M1 on the optical path of the outgoing light L1 between the light source unit 11 and the first filter 12. A beam splitter is provided. A beam splitter is provided on the optical path of the first transmitted light L11 between the first filter 12 and the beam splitter BS to separate the first transmitted light L11 and guide it to the light quantity monitoring unit M2. .

Next, the control unit 17 includes a light source control unit 17A that controls the light source unit 11 so as to adjust the light amount of the emitted light L1 based on the wavelength of the emitted light L1 and the light amount of the first transmitted light L11. For example, the light source control unit 17A acquires the wavelength of the emitted light L1 and the monitoring result of the first transmitted light L11 from the wavelength monitoring unit M1 and the light amount monitoring unit M2, respectively. Then, the light source control unit 17A adjusts the drive signal DL that drives the light emitting element 11A in the light source unit 11 based on the monitoring result. Thereby, for example, the output of the emitted light L1 changes.

Further, the control unit 17 controls the light transmission characteristics of the first and

second filters

12 and 14 based on the wavelength of the emitted light L1 and the light amount of the first transmitted light L11, thereby the first and second filters. The filter control unit 17B adjusts the wavelength range of the transmitted light L11 and L31. For example, the filter control unit 17B changes the transmission wavelength region of the first filter 12 based on the change in the wavelength of the emitted light L1. As a result, the wavelength range of the first transmitted light L11 changes.

2, for example, the light source unit 11, the first filter 12, the deflection unit 13, the beam splitter BS, the second filter 14, the light receiving unit 15, the wavelength monitoring unit M1, the light amount monitoring unit M2, and the like. The control unit 17 constitutes the scanning device SC.

Next, basic operations of the first and

second filters

12 and 14 will be described with reference to FIGS. 3A to 3D. First, FIG. 3A, FIG. 3B, FIG. 3C, and FIG. 3D are diagrams showing examples of spectra of the emitted light L1, the first transmitted light L11 (light projection signal), the incident light LS, and the second transmitted light L31, respectively. It is. In FIGS. 3A to 3D, the portions corresponding to the respective light amounts are hatched.

First, the case where the wavelength monitoring unit M1 detects that the emitted light L1 has the spectrum shown in FIG. 3A will be described. In this case, the first filter 12 transmits only part of the wavelength range of the outgoing light L1 including, for example, the peak wavelength (wavelength value corresponding to the maximum intensity) of the outgoing light L1 by the filter control unit 17B. It is adjusted to the wavelength band B1. Therefore, the first transmitted light L11 has a spectrum indicated by a solid line in FIG. 3B, for example.

Next, when the object OB is irradiated with the first transmitted light L11 having the spectrum illustrated in FIG. 3B as the scanning light L2, the incident light LS including the reflected light L3 may exhibit the spectrum illustrated in FIG. 3C, for example. is assumed.

Specifically, the incident light LS to the second filter 14 is a signal component that is a component corresponding to the reflected light L3 from the object OB, that is, a light component resulting from the reflection of the scanning light L2 by the object OB. Include as. Further, the incident light LS includes a component irrelevant to the reflected light L3, for example, a component corresponding to the environmental light L0 such as sunlight as a noise component. In many cases, the incident light LS is, for example, an optical signal in which these lights are superimposed.

Next, the second filter 14 is adjusted to the transmission wavelength band B2 corresponding to the transmission wavelength band B1 of the first filter 12 by the filter control unit 17B. For example, in the present embodiment, the second filter 14 is adjusted to a transmission wavelength band B2 that transmits only a part of the wavelength band of the first transmission light L11 as the second transmission light L31. ing. Accordingly, the second transmitted light L31 has a spectrum indicated by a solid line in FIG. 3D. Such second transmitted light L31 is incident on the light receiving unit 15.

Next, the operation of the first and

second filters

12 and 14 when the characteristics of the light source unit 11, that is, the characteristics of the emitted light L1, change will be described with reference to FIGS. 4A to 4D. 4A, FIG. 4B, FIG. 4C, and FIG. 4D respectively show the emitted light L1 and the first transmitted light L11 after the timing t1 when the wavelength (spectrum) of the emitted light L1 is different between the timing t0 and the timing t1. It is a figure which shows the example of the spectrum of incident light LS and the 2nd transmitted light L31.

First, consider a case where the outgoing light L1 is shifted to the long wavelength side. In this case, the emitted light L1 (t0) at the timing t0 and the emitted light L1 (t1) at the timing t1 have a spectrum as shown in FIG. 4A, for example. In FIG. 4A, the spectrum of the emitted light L1 (t0) is indicated by a broken line.

In this case, for example, the first filter 12 receives the wavelength change of the emitted light L1 from the wavelength monitoring unit M1, and for example, transmits the transmission wavelength band B1 by the wavelength change of the emitted light L1 (on the long wavelength side). To shift). Accordingly, at the predetermined timing t2 after the timing t1, the first filter 12 converts, for example, light in a predetermined wavelength range including the peak wavelength of the emitted light L1 (t1) after the wavelength change into the first transmitted light L11. (T2) is adjusted to be a transmission wavelength region B1 (t2) to be transmitted. Therefore, for example, at the timing t2, the first transmitted light L11 (t2) has a spectrum as shown in FIG. 4B.

In addition, when the first transmitted light L11 (t2) is projected as the scanning light L2, the incident light LS (caused by the first transmitted light L11 (t2) received at the timing t31 after the timing t2 It is assumed that t31) shows the spectrum shown in FIG. 4C. That is, the incident light LS (t31) is reflected light L3 (t31) caused by the first transmitted light L11 (t2), and the ambient light L0 (t0) incident on the second filter 14 simultaneously with the reflected light L3 (t31). t31).

In FIG. 4C, the spectrum of the incident light LS (t30) incident on the second filter 14 at the timing t30 due to the emitted light L1 (t0) at the timing t0, which is the timing before the change, is indicated by a broken line. .

In the present embodiment, the transmission wavelength band B2 of the second filter 14 is also set by the filter control unit 17B at the timing t2 (that is, the timing at which the transmission wavelength band B1 of the first filter 12 is adjusted) or the subsequent timing. Adjusted. For example, in the second filter 14, the transmission wavelength band B2 is adjusted to the long wavelength side at a timing immediately after the timing t2. Therefore, at the timing t31 when the incident light LS enters the second filter 14, the second transmitted light L31 (t31) has a spectrum as shown in FIG. 4D.

Thus, in this embodiment, for example, when the characteristic of the light source unit 11 (the light emission characteristic of the light emitting element 11A) changes, the first and

second filters

12 and 14 are transmitted through the transmission wavelength region according to the characteristic change. B1 and B2 are changed. Further, the transmission wavelength ranges B1 and B2 of the first and

second filters

12 and 14 are adjusted as needed in accordance with the characteristic change of the light source unit 11.

Therefore, even when the characteristics of the emitted light L1 change, the light quantity of the first transmitted light L11 (that is, the scanning light L2) can be stabilized by adjusting the characteristics of the first filter 12.

Further, by adjusting the characteristics of the second filter 14 in accordance with the adjustment of the characteristics of the first filter 12, the incident light LS including the reflected light L3 (signal component) and the ambient light L0 (noise component) can be appropriately selected. The ambient light L0 can be removed. For example, in this embodiment, as shown in FIGS. 3D and 4D, the transmission wavelength band B2 of the second filter 12 is completely included in the transmission wavelength band B1 of the first filter 12, and the first filter 12 is used. The transmission wavelength region B2 of the second filter 12 is adjusted so as to be narrower than the transmission wavelength region B1.

In other words, in the present embodiment, the second filter 12 transmits only light in a part of the wavelength band B1 of the first filter 12 as the second transmitted light L31. Have As a result, almost all the environmental light L0 having a wavelength different from that of the reflected light L3 can be removed. Therefore, the reflected light L3 can be extracted appropriately, and the scanning accuracy and distance measurement accuracy are improved.

Note that the transmission wavelength region B2 of the second filter 12 and the transmission wavelength region B1 of the first filter 12 may be completely the same.

In consideration of adjusting the transmission wavelength region B2 of the second filter 14 more accurately, the distance measuring device 10 has a wavelength monitoring unit (not shown) that monitors the wavelength of the second transmitted light L31. You may do it. In this case, the filter control unit 17B may control the first and

second filters

12 and 14 while monitoring the wavelengths of the first and second transmitted lights L11 and L31.

Next, the output adjustment operation of the light source unit 11 will be described with reference to FIGS. 5A to 5C. For ease of understanding, in FIGS. 5A to 5C, when only the light amount of the emitted light L1 is adjusted by the light source unit 11 and the characteristics of the first filter 12 are not adjusted (that is, the wavelength of the emitted light L1 is (Assuming no change). In addition, here, as an example, a case where the light amount adjustment of the emitted light L1 is performed as an initial setting before actual scanning is performed will be described.

FIG. 5A is a diagram showing an example of the spectrum of the outgoing light L1 before adjustment. First, consider a case where the emitted light L1 (t01) has a light amount AM1 (t01) corresponding to the area indicated by hatching in FIG. 5A at the timing t01 before adjustment.

FIG. 5B is a diagram illustrating an example of a spectrum of the first transmitted light L11 (t0) when the emitted light L1 (t01) is incident on the first filter 12. For example, when the first filter 12 is set to the transmission wavelength region B1 shown in FIG. 3B as an initial setting, the light amount AM11 (t01) of the first transmitted light L11 (t01) is the area shown by hatching in FIG. 5B. The amount corresponds to.

In the present embodiment, the light source control unit 17A drives the light source unit 11 so that the light amount AM (t01) of the first transmitted light L11 (t01) becomes a light amount (predetermined light amount) that satisfies safety standards. Take control. That is, the light source unit 11 is driven so as to emit the emitted light L1 controlled based on the light amount AM11 of the first transmitted light L11.

Specifically, in this embodiment, the scanning light L2 projected onto the scanning region R0 has a light amount corresponding to the first transmitted light L11 that is a part of the emitted light L1 from the light source unit 11. It becomes. Therefore, for example, the restriction condition of the light quantity of the scanning light L2, such as the safety standard of the laser light, may be calculated based on the first transmitted light L11. For example, the light quantity of the 1st transmitted light L11 should just satisfy | fill safety standards.

For example, when the light amount AM11 (t01) of the first transmitted light L11 (t01) at the timing t01 detected (calculated) by the light amount monitoring unit M2 is sufficiently small with respect to the safety standard, The output of the light source unit 11 is adjusted so that the light amount AM1 of the emitted light L1 is increased.

In this case, for example, at the adjusted timing t02, as shown in FIG. 5C, the light source unit 11 emits the emitted light L1 (t02) having a higher output than the emitted light L1 (t01) at the timing t01. . Therefore, the light amount AM1 (t02) of the emitted light L1 (t02) is larger than the light amount AM1 (t02) of the emitted light L1 (t01) at the timing t01.

Thus, in the present embodiment, the light source unit 11 is configured to adjust the light amount of the emitted light L1 based on the light amount AM11 of the first transmitted light L11 that has passed through the first filter 12. . Therefore, for example, the scanning region R0 can be scanned with the scanning light L2 having a sufficient amount of light within a range that satisfies the constraint conditions such as safety standards.

The light source unit 11 may adjust the light amount AM1 of the emitted light L1 even during the operation of the distance measuring device 10 (scanning device SC). For example, the light amount adjustment of the emitted light L1 by the light source unit 11 is performed when the light amount AM1 of the first transmitted light L11 changes by a predetermined amount or more, such as when the transmission wavelength range B1 of the first filter 12 is adjusted. May be performed again. Further, for example, when the light amount AM1 of the emitted light L1 is expected to approach the upper limit of the safety standard by adjusting the transmission wavelength band B1, the light source unit 11 may perform adjustment to lower the output by the light source control unit 17A. Good.

In the above description, the case where the transmission wavelength ranges B1 and B2 of the first and

second filters

12 and 14 are adjusted has been described. Further, a case has been described in which the light amount monitoring unit M2 measures (calculates) the light amount AM11 of the first transmitted light L11 and the light amount AM1 of the emitted light L1 is adjusted so that the result is fed back to the light source unit 11.

That is, in the present embodiment, the first filter 12 is a wavelength tunable filter that changes the transmission wavelength band B1 according to the wavelength of the outgoing light L1. The second filter 14 is a wavelength tunable filter that changes the transmission wavelength range B2 based on the transmission wavelength range B1 of the first filter 12. In addition, the light source unit 11 emits light of the light amount AM1 based on the light amount AM11 of the first transmitted light L11 as the emitted light L1.

However, the first and

second filters

12 and 14 are not limited to being wavelength tunable filters. For example, as long as the light source unit 11 is used in a design environment (within an assumed range), the wavelength characteristics are often hardly changed. Therefore, for example, if the characteristics of the emitted light L1 from the designed light source unit 11 are acquired in advance, the first and

second filters

12 and 14 correspond to the characteristics of the designed emitted light L1. A fixed wavelength filter having transmission wavelength ranges B1 and B2 may be used.

In other words, the first filter 12 is a filter configured to transmit only light in a partial wavelength region of the emitted light (pulse light) L1 from the light source unit 11 as the first transmitted light L11. If it is. Further, the second filter 14 emits light in a wavelength region that overlaps or coincides with the wavelength region of the first transmitted light L11 out of the reflected light L3 reflected by the scanning light L2 from the object OB in the scanning region R0. Any filter configured to transmit the second transmitted light L31 may be used.

For example, when the first filter 12 is a fixed wavelength filter, the light amount AM11 of the first transmitted light L11 can be calculated without actually measuring if the wavelength (spectrum) of the emitted light L1 is known. be able to. Accordingly, in consideration of projecting a sufficient amount of scanning light L2, for example, the light source unit 11 is configured to emit light having a light amount corresponding to the wavelength region of the emitted light L1 as the emitted light L1. Also good.

In the present embodiment, the case where the characteristics of the light source unit 11, the first filter 12, and the second filter 14 are adjusted by the control unit 17 has been described. However, the light source unit 11, the first filter 12, or the second filter 14 may be configured to independently adjust the characteristics without being controlled by the control unit 17. For example, the control program of the control unit 17 may be installed in the light source unit 11, the first filter 12, or the second filter 14.

In the present embodiment, all the characteristics of the light source unit 11, the first filter 12, and the second filter 14 may be fixed. Specifically, as described above, it is assumed that the characteristics of the light source unit 11 hardly change under a design environment. Therefore, each of the light source unit 11, the first filter 12, and the second filter 14 may be fixed to design characteristics. That is, the light source unit 11 may be a light source configured to emit the emitted light L1.

Next, an example of the configuration of the deflection unit 13 will be described with reference to FIGS. 6A and 6B. FIG. 6A is a schematic top view of the deflecting unit 13. FIG. 6B is a cross-sectional view of the deflection unit 13. 6B is a cross-sectional view taken along line VV in FIG. 6A. In this embodiment, the deflecting unit 13 is a MEMS (Micro Electro Mechanical Systems) mirror that includes a oscillating mirror 24 having a light reflecting surface 13A and that the oscillating mirror 24 oscillates.

In this embodiment, the deflecting unit 13 is configured to electromagnetically oscillate the oscillating mirror 24. More specifically, the deflection unit 13 includes a fixed unit (base unit) 21, a swing unit (movable unit) 22, a driving force generation unit 23, and a swing mirror 24. In the present embodiment, the deflection unit 13 is configured such that the oscillating mirror 24 oscillates around two oscillating shafts (first and second oscillating shafts) AX and AY orthogonal to each other. ing.

In this embodiment, the fixing portion 21 includes a fixed substrate B1 and an annular fixed frame B2 formed on the fixed substrate B1. The swing part 22 includes a pair of torsion bars (first torsion bars) TX each having one end fixed inside the fixed frame B2. Each of the pair of torsion bars TX is composed of a rod-shaped elastic member having at least circumferential elasticity, and is aligned along the swing axis AX. Further, the swing part 22 has an annular swing frame (movable frame) SX whose outer peripheral side surface is connected to the other end of each of the pair of torsion bars TX.

Each of the swinging portions 22 is connected to a side surface of the inner peripheral portion of the swinging frame SX and has a pair of torsion lines aligned in a direction perpendicular to the pair of torsion bars TX (a direction along the swinging axis AY). It has a bar (second torsion bar) TY and a swing plate (movable plate) SY whose outer peripheral side surface is connected to the other end of each of the pair of torsion bars TY. Each of the pair of torsion bars TY is composed of a rod-like elastic member having at least circumferential elasticity.

In this embodiment, the swing frame SX swings about the swing axis AX (with the swing center), and the swing plate SY swings about the swing axes AX and AY. A swing mirror 24 is formed on the swing plate SY. For example, the oscillating mirror 24 is a light reflective film formed on the oscillating plate SY. The light reflecting surface 13A of the oscillating mirror 24 oscillates around the oscillating axes AX and AY orthogonal to each other together with the oscillating plate SY.

The driving force generation unit 23 includes a magnet MG disposed on the fixed substrate B1, a metal wiring (first coil) CX wired along the outer periphery of the swing frame SX on the swing frame SX, and a swing And a metal wiring (second coil) CY wired along the outer periphery of the swing plate SY on the plate SY.

In the present embodiment, the magnet MG is composed of a plurality of magnet pieces provided in the outer region of the fixed frame B2 on the fixed substrate B1. In the present embodiment, four magnet pieces are respectively disposed along the swing axes AX and AY and at positions outside the pair of torsion bars TX and TY.

Further, the two magnet pieces facing each other in the direction along the swing axis AX are arranged so that portions having opposite polarities face each other. Similarly, the two magnet pieces facing each other in the direction along the swing axis AY are arranged so that the portions having opposite polarities face each other.

In the present embodiment, when a current flows through the metal wiring CX, the pair of torsion bars TX are rotated by the interaction with the magnetic field generated by the two magnet pieces of the magnet MG aligned in the direction along the swing axis AY. The swing frame SX swings about the swing axis AX. Similarly, the pair of torsion bars TY is twisted and the swing plate SY swings due to the electric field generated by the current flowing through the metal wiring CY and the magnetic field generated by the two magnet pieces of the magnet MG aligned in the direction along the swing frame AX. It swings around the axis AY.

Further, as shown in FIG. 6A, the metal wirings CX and CY are connected to the control unit 17. The control unit 17 supplies drive signals DX and DY to the metal wirings CX and CY. The driving force generation unit 23 generates an electromagnetic force that swings the swinging unit 22 and the swinging mirror 24 by applying the drive signals DX and DY.

In this embodiment, the oscillating mirror 24 has a disk shape. The oscillating mirror 24 has a central axis AC orthogonal to the oscillating axes AX and AY. The oscillating portion 22 and the oscillating mirror 24 are formed to be 90-degree rotationally symmetric with respect to the central axis AC of the oscillating mirror 24.

Referring to FIG. 6B, in the present embodiment, the fixed substrate B1 of the fixed portion 21 has a recess. The fixed frame B2 is fixed to the fixed substrate B1 so that the swinging portion 22 is suspended in the concave portion of the fixed substrate B1. Further, the fixed frame B2 and the swinging portion 22 (the swinging frame SX, the swinging plate SY, and the torsion bars TX and TY) are portions of the semiconductor substrate formed by processing the semiconductor substrate, for example.

The oscillating mirror 24 is suspended (supported) together with the oscillating plate SY so as to be able to oscillate in the concave portion of the fixed substrate B1. Moreover, the magnet MG is formed outside the concave portion on the fixed substrate B1. Further, in the present embodiment, the torsion bars TX and TY are twisted, so that both ends of the swinging part 22 sandwiching the torsion bars TX and TY are directed toward the recesses of the fixed substrate B1 inside the fixed frame B2. Swings away. Further, the oscillating mirror 24 oscillates so as to be inclined with respect to the fixed frame B2 with one point on the central axis AC as the oscillating center.

When the oscillating mirror 24 (light reflecting surface 13A) oscillates, the reflection direction of the first transmitted light L11, that is, the light projecting direction of the scanning light L2 changes. In this way, the deflecting unit 13 (light projecting unit) includes the oscillating mirror 24 that deflects the first transmitted light L11 in a variable direction, and the deflected first transmitted light L11 is used as the scanning light L2. Light is projected toward the scanning region R0.

That is, in the present embodiment, the deflecting unit 13 includes the oscillating mirror 24 that reflects the first transmitted light L11 and oscillates around the oscillating axes AX and AY orthogonal to each other. For example, the deflecting unit 13 oscillates the oscillating mirror 24 so as to project the scanning light L2 onto the scanning region R0 in a manner according to a scanning method such as raster scanning or Lissajous scanning.

In addition, when the deflection | deviation part 13 contains a MEMS mirror, the rocking | fluctuation mirror 24 is not limited to the case where it rock | fluctuates around the rocking axes AX and AY orthogonal to each other. For example, the swing axes AX and AY do not have to be orthogonal to each other, and may be axes that are along different directions. Further, the oscillating mirror 24 is not limited to oscillating around the two oscillating axes AX and AY. For example, the oscillating mirror 24 oscillates around one oscillating axis (for example, only the oscillating axis AX). It may be configured. In other words, the deflecting unit 13 may have, for example, the oscillating mirror 24 that reflects the first transmitted light L11 and oscillates around at least one axis.

As described above, the distance measuring device 10 includes the light source unit 11 and the first filter 12 that transmits only light in a partial wavelength region of the emitted light L1 from the light source unit 11 as the first transmitted light L11. A light projecting unit 13 that projects the first transmitted light L11 as the scanning light L2 toward the predetermined region R0, and the reflected light L3 reflected by the object OB in the predetermined region R0. Among them, the second filter 14 that transmits the light in the wavelength region overlapping the wavelength region of the first transmitted light L11 as the second transmitted light L31, the light receiving unit 15 that receives the second transmitted light L31, and the light reception And a distance measuring unit 16 that measures the distance to the object OB based on the light reception result of the second transmitted light L31 by the unit 15. Therefore, a scanning type measurement capable of performing accurate optical scanning in the scanning region R0 by projecting an appropriate amount of light onto the object OB and appropriately removing noise components of the received light. A distance device 10 can be provided.

Also, the scanning information signal SR generated by the light receiving unit 15 can be used for purposes other than ranging. That is, the distance measuring device 10 operates as the scanning device SC when the distance measuring unit 15 is not provided.

Accordingly, the scanning device SC includes, for example, the light source unit 11, the first filter 12 that transmits only the light in the partial wavelength region of the emitted light L1 from the light source unit 11 as the first transmitted light L11, Of the light projecting unit 13 that projects the first transmitted light L11 toward the predetermined region R0 as the scanning light L2, and the reflected light L3 reflected by the object OB in the predetermined region R0, It has the 2nd filter 14 which permeate | transmits the light of the wavelength range which overlaps with the wavelength range of the 1st transmitted light L11 as the 2nd transmitted light L31, and the light-receiving part 15 which receives the 2nd transmitted light L31. Accordingly, the scanning device SC capable of performing accurate optical scanning in the scanning region R0 by projecting an appropriate amount of light onto the object OB and appropriately removing noise components of the received light. Can be provided.

FIG. 7 is a diagram illustrating a schematic configuration example of a distance measuring apparatus 10A according to a modification of the first embodiment. FIG. 7 shows only the configuration of the scanning device SC1 included in the distance measuring device 10A. The distance measuring device 10A has a single filter 18 provided on a common optical path for the emitted light L1 and the reflected light L3 in place of the first and

second filters

12 and 14, and the configuration of the control unit 19 The configuration is the same as that of the distance measuring device 10 except for.

In other words, the scanning device SC1 of the distance measuring device 10A includes the light source unit 11 and a deflecting unit that projects the emitted light L1 from the light source unit 11 toward the predetermined region R0 as the scanning light L2 while deflecting the emitted light L1 in a variable direction. 13 and the light receiving unit 15 that receives the reflected light L3 reflected by the object OB in the predetermined region R0, and the optical path of the outgoing light L1 and the optical path of the reflected light L3. One filter 18.

In the present modification, the scanning device SC1 is provided on the optical path of the outgoing light L1 between the light source unit 11 and the deflecting unit 13, and is reflected light L3 that has passed through the deflecting unit 13 (reflected light returning to the deflecting unit 13). A beam splitter BS is provided as a light projecting / receiving separation unit for guiding L3) to the light receiving unit 15. The filter 18 is provided on a common optical path for the outgoing light L1 and the reflected light L3 between the beam splitter BS and the deflecting unit 13.

For example, the filter 18 has the same configuration as the first filter 12 in the distance measuring device 10. For example, the filter 18 is a wavelength tunable filter that changes the transmission wavelength band B <b> 1 according to the wavelength of the emitted light L <b> 1 from the light source unit 11. The filter 18 is controlled by a filter control unit 19A of the control unit 19.

As in this modification, a common optical path is provided for the optical path of the emitted light L1 between the light source unit 11 and the deflecting unit 13 and the optical path of the reflected light L3 between the deflecting unit 13 and the light receiving unit 15. In this case, the same operation as that of the scanning device SC can be performed by arranging one filter 18 in the common optical path.

The scanning device SC1 can perform the same operation with a simple configuration as compared with the case where the scanning device SC1 has two filters (first and second filters 12 and 14) as in the scanning device SC.

As shown in the present embodiment and its modification, the emitted light L1 from the light source unit 11 is deflected by the deflecting unit 13 (or before being projected toward the scanning region R0 as the scanning light L2). It is converted into first transmitted light L11 which is light in a part of the wavelength range. Further, the incident light LS including the reflected light L3 from the object OB is converted into the second transmitted light L31 that is light in a part of the wavelength region before being received by the light receiving unit 15. Moreover, according to the wavelength of the emitted light L1 from the light source part 11, the wavelength range and the light quantity of the 1st and 2nd transmitted light L11 and L31 are adjusted. Accordingly, it is possible to perform optical scanning and ranging using the scanning light L2 having the optimum characteristics in accordance with the scanning environment (ranging environment) and the characteristic change of the light source unit 11.

FIG. 8 is a diagram illustrating a schematic configuration example of the distance measuring device 30 according to the second embodiment. The distance measuring device 30 has the same configuration as the distance measuring device 10 except for the configurations of the first and

second filters

31 and 33, the deflecting unit (light projecting unit) 32, and the control unit 34. FIG. 8 shows only the configuration of the scanning device SC2 included in the distance measuring device 30.

In the present embodiment, the scanning device SC2 transmits only light in a part of the wavelength region of the emitted light L1 from the light source unit 11 as the first transmitted light L11 and periodically the first transmitted light L1. The first filter 31 is continuously changed. That is, the first filter 31 is a wavelength variable filter that continuously changes the transmission wavelength range.

For example, the first filter 31 sets the transmission wavelength region so that the wavelength region λ0 is the central wavelength region, and the wavelength of the first transmitted light L11 is continuously changed between the wavelength region λ1 and the wavelength region λ2. Change.

In the scanning device SC2, the deflecting unit 32 includes a diffraction grating 32A that emits light in different directions according to the wavelength of the first transmitted light L11. In the present embodiment, the diffraction surface of the diffraction grating 32 </ b> A is fixed with respect to the first filter 31. That is, the present embodiment is an example of a device configuration when the deflecting unit 32 includes an optical element other than the MEMS mirror as a deflecting element.

In the scanning device SC2, the first filter 31 causes the light whose wavelength is continuously and periodically changed to enter the diffraction grating 32A as the first transmitted light L11. Then, the direction of emission from the diffraction grating 32A changes for each wavelength of the first transmitted light L11, whereby the first transmitted light L11 is deflected. Thereby, the deflected light is projected toward the scanning region R0 as the scanning light L2.

That is, in the present embodiment, the first filter 31 and the deflecting unit 32 (diffraction grating 32A) function as a scanning unit (sweep unit) that sweeps the scanning region R0 with the scanning light L2. The width of the transmission wavelength region of the first filter 31 can be determined based on, for example, the grating constant (grating interval) of the diffraction grating 32A.

The second filter 33 is a wavelength tunable filter that changes the transmission wavelength range according to the transmission wavelength range of the first filter 31. In the present embodiment, the second filter 33 is configured to periodically change the transmission wavelength range between the wavelength range λ1 and the wavelength range λ2 in conjunction with the first filter 31.

The control unit 34 also controls the light source control unit 34A that controls the light source unit 11 and the first and

second filters

31 and 33 based on the monitoring results of the wavelength monitoring unit M1 and the light amount monitoring unit M2. Part 34B.

Next, the operation of the first and

second filters

31 and 33 will be described with reference to FIGS. 9A to 9D. 9A, 9B, 9C, and 9D are diagrams illustrating examples of spectra of the emitted light L1, the first transmitted light L11 (projection signal), the incident light LS, and the second transmitted light L31, respectively. .

The first filter 31 has a transmission wavelength band B3 (λ1) that transmits light in the wavelength band λ1 and a transmission wavelength band B3 (λ2) that transmits light in the wavelength band λ2 with a predetermined bandwidth by the filter control unit 34B. The transmission wavelength band B3 is periodically changed between For example, when the transmission wavelength region B3 of the first filter 31 is the intermediate wavelength region λ0 between the wavelength region λ1 and the wavelength region λ2, the first transmitted light L11 (λ0) has the spectrum shown in FIG. 9B. Show. Further, the light amount AM11 (λ0) of the first transmitted light L11 (λ0) is a portion indicated by hatching in FIG. 9B.

Note that, as shown in FIG. 9B, it is assumed that the light amount AM11 of the first transmitted light L11 varies depending on the wavelength region (for example, between the wavelength regions λ0, λ1, and λ2). Therefore, for example, when it is detected from the monitoring result of the light amount monitoring unit M2 that the light amount AM11 of the first transmitted light L11 changes by a predetermined amount or more depending on the wavelength range, the light source control unit 34A performs the first transmitted light L11. The light amount AM1 of the emitted light L1 may be adjusted by controlling the light source unit 11 so that the light amount AM11 falls within a predetermined range (for example, constant).

Moreover, when the object OB is irradiated with the first transmitted light L11 (λ0) having the spectrum illustrated in FIG. 9B as the scanning light L2, the incident light LS including the reflected light L3 (λ0) is, for example, illustrated in FIG. 9C. It is assumed to show a spectrum. Further, the incident light LS includes a component (signal component) corresponding to the reflected light L3 (λ0) and a component (noise component) corresponding to the environmental light L0.

The second filter 33 is adjusted to a transmission wavelength band B4 corresponding to the transmission wavelength band B3 of the first filter 31 by the filter control unit 34B. For example, when the transmission wavelength range B3 of the first filter 31 is adjusted to the transmission wavelength range B3 (λ0), the second filter 33 is reached by the timing at which the incident light LS corresponding to this is assumed to be received. The transmission wavelength band B4 is adjusted to the transmission wavelength band B4 (λ0). For example, the transmission wavelength range B4 (λ0) of the second filter 33 is adjusted to be the same as the transmission wavelength range B3 (λ0) of the first filter 31. Therefore, the second transmitted light L31 (λ0) has a spectrum indicated by a solid line in FIG. 9D.

In the present embodiment, the first filter 31 has a wavelength of the first transmitted light L11 within the range of the direction of the scanning light L2 to be projected, that is, within the range of the wavelength region to be incident on the diffraction grating 32A. The transmission wavelength region B3 is changed so as to adjust the width of the region. In the present embodiment, the light source unit 11 emits, for example, light having a light amount AM1 corresponding to the light amount AM11 of the first transmitted light L11 as the emitted light L1. Accordingly, it is possible to project an appropriate amount of light as the scanning light L2, and to appropriately remove noise components in the incident light LS. Further, the light amount of the scanning light L2 is stabilized. Therefore, accurate scanning and ranging can be performed.

In this embodiment, the diffraction grating 32A functioning as the deflecting unit 32 does not need to be operated like the oscillating mirror 24 of the deflecting unit 13. Therefore, the same scanning information can be obtained by controlling the first and

second filters

31 and 33. Therefore, the operation quality and stability of the scanning device SC2 or the distance measuring device 30 are improved.

In the present embodiment, the case where the scanning device SC2 includes the first and

second filters

31 and 33 has been described. However, the scanning device SC2 is not limited to the case where the first and

second filters

31 and 33 are included. For example, like the scanning device SC1 according to the modification of the first embodiment, a common optical path may be provided for the emitted light L1 and the reflected light L3, and one filter may be disposed on the common optical path.

10, 10A, 30 Ranging devices SC, SC1, SC2 Scanning device 11

Light source unit

12, 31

First filter

13, 32 Deflection unit (light projection unit)
14, 33 Second filter 18 Filter 15 Light receiving portion

Claims

A light source unit;
A first filter that transmits only a part of the wavelength region of the emitted light from the light source unit as the first transmitted light;
A light projecting unit that projects the first transmitted light toward a predetermined region as scanning light;
A second filter that transmits, as second transmitted light, light in a wavelength region that overlaps with the wavelength region of the first transmitted light among reflected light that is reflected by the object in the predetermined region of the scanning light; ,
And a light receiving portion that receives the second transmitted light.
2. The scanning device according to claim 1, wherein the first filter is a wavelength tunable filter that changes a transmission wavelength region in accordance with a wavelength of the emitted light from the light source.
3. The scanning device according to claim 2, wherein the second filter is a wavelength tunable filter that changes a transmission wavelength range according to the transmission wavelength range of the first filter.
The said 2nd filter permeate | transmits only the light of the one part wavelength range of said 1st transmitted light among said reflected lights as said 2nd transmitted light, Any one of Claim 1 thru | or 3 characterized by the above-mentioned. A scanning device according to claim 1.
5. The scanning device according to claim 1, wherein the light source unit emits light having a light amount based on a light amount of the first transmitted light as the emitted light.
The scanning device according to claim 1, wherein the light source unit emits light having a light amount corresponding to a wavelength range of the emitted light as the emitted light.
The light projecting unit includes an oscillating mirror that reflects the first transmitted light and oscillates around at least one axis to deflect the first transmitted light in a variable direction. The scanning device according to claim 1.
The first filter is a wavelength tunable filter that changes a transmission wavelength range;
The scanning device according to claim 1, wherein the light projecting unit includes a diffraction grating that emits light in different directions according to the wavelength of the first transmitted light.
A scanning device according to any one of claims 1 to 8,
A distance measuring device comprising: a distance measuring unit that measures a distance to the object based on a result of receiving the second transmitted light by the light receiving unit.
A light source unit;
A deflecting unit that projects light toward a predetermined region as scanning light while deflecting light emitted from the light source unit in a variable direction;
A light receiving unit that receives the reflected light reflected by the object in the predetermined region, and
And a filter provided on the optical path of the outgoing light and on the optical path of the reflected light.
A light projecting / receiving separation unit that is provided on an optical path of the emitted light between the light source unit and the deflecting unit and guides the reflected light that has passed through the deflecting unit to the light receiving unit;
The scanning device according to claim 10, wherein the one filter is provided on an optical path common to the emitted light and the reflected light between the deflecting unit and the light projecting and receiving separation unit.
The scanning device according to claim 11, wherein the light projecting / receiving separation unit is a beam splitter.