Classifications

• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
  • G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
  • G01S7/48—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S17/00
  • G01S7/481—Constructional features, e.g. arrangements of optical elements
  • G01S7/4816—Constructional features, e.g. arrangements of optical elements of receivers alone
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
  • G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
  • G01S7/48—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S17/00
  • G01S7/481—Constructional features, e.g. arrangements of optical elements
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q3/00—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system
  • H01Q3/12—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system using mechanical relative movement between primary active elements and secondary devices of antennas or antenna systems
  • H01Q3/14—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system using mechanical relative movement between primary active elements and secondary devices of antennas or antenna systems for varying the relative position of primary active element and a refracting or diffracting device

Definitions

• the invention relates to a LIDAR device for scanning a scanning angle and to a method for scanning a scanning angle with a LIDAR device.
• LI DAR light detection and ranging
• the transmitting device generates and emits continuously or pulsed electromagnetic radiation. If this electromagnetic radiation strikes a movable or stationary object, the electromagnetic radiation from the object in the direction of
• the receiving device can detect the reflected electromagnetic radiation and assign it a reception time. This can be done as part of a "time of flighf analysis for a
• Determining a distance of the object to the LIDAR device can be used. Depending on the application, high demands are placed on the
• the signal quality determines up to which distance, under which angle and with which accuracy or probability objects can be detected.
• This signal quality results to a large extent from the quality of the optical filtering of the received reflected radiation.
• the decisive factor here is the width of the spectral bandpass of a filter that can be used. The narrower the spectral bandwidth of the filter, the less interference or ambient light falls on the detector and the better the signal quality. Since this passband with increasing angle of incidence of the received radiation to smaller Wavelengths is shifted, the filter must have a certain width in order to be able to transmit the received radiation even at large angles.
• the angle of incidence-dependent shift of the transmission window of the filters represents a physical limit of LIDAR devices.
• the object underlying the invention can be seen to provide a method and a LIDAR device having at least one filter which, despite a varying angle of incidence of an incident beam always has an optimal transmission characteristic.
• a LIDAR device for scanning a scan angle.
• the LIDAR device has at least one radiation source for generating at least one electromagnetic beam, a rotatable mirror for deflecting the at least one
• the LIDAR device has a receiving unit for receiving at least one incoming electromagnetic beam and for deflecting the at least one incoming electromagnetic beam to at least one detector and at least one filter, wherein the at least one filter is adaptable to the at least one incoming electromagnetic beam.
• Such a LIDAR device has a dynamic optical filter that can compensate for an incident angle-dependent wavelength shift of an incoming beam. Especially with larger angles of incidence, a transmission range of the filter for a particular
• the filter can be adjusted to a limited extent or not at all. This can be done, for example realize an adaptation of a position of the filter or by adjusting at least one material property of the filter. This allows the
• Receiver unit be customizable.
• the filter can be any type of media
• the transmission ranges here refer to a wavelength or frequency of an electromagnetic beam.
• the electromagnetic beam may, for example, be a laser beam or light beam in the visible or invisible wavelength range.
• the at least one filter is rotatable along the scanning angle.
• the filter is rotatable or rotatably mounted, so that its orientation can be changed.
• the wavelength of the incoming beam can always be in at least one
• Transmissions Kunststoff the filter and pass as low loss filter.
• An optimal angle of incidence is ideally 0 °.
• the angle of incidence may vary depending on a transmission characteristic of the filter and the
• Wavelength shift of the incident beam also deviate from 0 °.
• the at least one filter is angularly offset or angle-synchronized relative to the rotatable mirror.
• the filter can be adjusted or adjusted in its orientation depending on the mirror.
• the filter can also be rotated or pivoted independently of the mirror for deflecting the generated electromagnetic beam.
• the filter can be adapted, for example, time-dependent, so that an angular offset between the filter and the mirror can be realized.
• the entire receiving device or parts of the receiving device can be rotatable or pivotable parallel to the filter.
• the at least one filter is an adjustable Fabry-Perot cavity.
• the filter may be a conventional optical filter or an optical resonator.
• the Fabry-Perot cavity corresponds to an optical resonator, which consists of at least two semitransparent mirrors. Depending on a distance or a
• Cavity length of the two partially transmissive mirror to each other can only happen incoming electromagnetic radiation of a certain wavelength.
• the partially transmissive mirror may have a low reflectivity.
• the at least one filter has an adjustable cavity length. The distance between the two semitransparent mirrors can be changed so that the
• Transmission wavelength of the Fabry-Perot cavity can be adjusted.
• Piezo actuators or electrostatic or electromagnetic linear actuators are adjusted. By adjusting the partially transparent mirror cavity length can be changed or adjusted and thus the
• the cavity length is adjustable depending on an orientation of the rotatable mirror.
• Cavity length of the Fabry-Perot cavity corresponding to the deflection of the mirror to deflect the generated beam can be reduced or increased.
• the reflected electromagnetic beam has a similar
• Transmission range can be adapted to the angle of incidence. This ensures that the incoming beam can always pass through the filter.
• the at least one filter has an adjustable refractive index. A change of the
• Refractive indices can be done for example by dynamic alignment of liquid crystals by electrical or magnetic fields.
• the wavelength shift of the incoming beam the
• Transmission range of the filter can be dependent on its temperature, This effect can be used to set the transmission range or the
• the refractive index is dependent on a density of the material and thus also dependent on the temperature.
• the refractive index can also be adjusted by a temperature of the filter or a part of the filter.
• the partially transmissive mirrors are vapor deposited or deposited on a glass or transparent substrate.
• This carrier material can experience a change in the refractive index by application of temperature and / or electrical or magnetic fields.
• the refractive index can also have an influence on the transmission range.
• the filter or at least a portion of the filter may be cooled or heated to undesirable effects
• the temperature can be any suitable temperature that compensate or adjust the filter.
• the temperature can be any suitable temperature that compensate or adjust the filter.
• the filter can be lowered for example by air or water cooling.
• the filter can be heated by heated water or heated air.
• the heating of the filter can be carried out by an electrically conductive layer or coating.
• one or more glass elements of the filter can be heated by Joule heat.
• the LIDAR device is the
• Refractive index adjustable depending on the orientation of the rotatable mirror is adjusted such that the transmission range of the filter to the wavelength shift or the
• Incident angle of the incoming beam is adjusted.
• the refractive index of the filter or a part of a filter such as glass the transmission range can be tracked so that the incoming beam as completely as possible and loss-free can pass through the filter.
• At least two filters for filtering the at least one incoming electromagnetic beam are arranged angularly offset from one another.
• a plurality of filters may be used, which are arranged at an angle to each other. This allows each filter to react less dynamically to an incoming beam since the angle of incidence can not be as great as with a single static filter.
• the angle of incidence of the incoming beam is relative to a filter increasing number of static or dynamic filters, which are set up, for example, semi-circular increasingly reduced.
• each filter can be adaptable or changeable depending on the angle of incidence or at least one adjacent filter.
• all or some of the filters may be regular optical filters that do not have dynamic matching.
• the at least one filter for filtering the at least one incoming electromagnetic beam has a curvature.
• a filter may be used which has a curvature which at least partially covers a scanning angle of the LIDAR device and thus covers an angular range at which an incoming reflected beam can strike the filter.
• the filter may be oriented such that, regardless of the angle of incidence of the
• the filter can additionally provide a dynamic adjustment of the
• Such a filter may alternatively have a curvature which is a
• the filter may be advantageous to move the filter along at least one length in order to adapt the filter to an incoming beam.
• a method of scanning a scan angle with a LIDAR device In one step, at least one electromagnetic beam is generated and along the
• the at least one deflected electromagnetic beam can be reflected at an object positioned at the scanning angle.
• the at least one reflected electromagnetic beam becomes at least one incoming beam and is received and filtered.
• the at least one incoming beam is detected, wherein at least one filter is adjusted according to a wavelength and / or an angle of incidence of the at least one incoming beam.
• the filter may be adapted to a wavelength of the incoming beam depending on an angle of incidence of the incoming beam. It is thus possible to move or rotate the filter so that an incoming beam in as small as possible Incident angle relative to the filter meets this.
• material properties of the filter can be adapted.
• a cavity length can be dynamically varied by one adapted to the wavelength of the incoming beam
• the adaptation can be carried out continuously in accordance with a sampling rate of the method.
• FIG. 1 is a schematic representation of a LIDAR device according to a first embodiment
• FIG. 2 is a schematic representation of a receiving unit of the LIDAR device according to the first embodiment
• FIG. 3 is a schematic representation of the receiving unit of the LIDAR device according to a second embodiment
• FIG. 4 shows a schematic representation of the receiving unit of the LIDAR device according to a third exemplary embodiment
• 5a, b is a schematic representation of the receiving unit of the LIDAR device according to a fourth embodiment
• Fig. 6 is a schematic representation of the receiving unit of the LIDAR device according to a fifth embodiment.
• Fig. 7 is a schematic representation of the receiving unit of the LIDAR device according to a sixth embodiment.
• FIG. 1 shows a first exemplary embodiment of a LIDAR device 1.
• the LIDAR device 1 has a radiation source 2 for generating an electromagnetic beam 4.
• the radiation source 2 is in accordance with
• a laser 2 is used to generate a beam 4 with a wavelength in the non-visible infrared ready.
• the wavelength can be greater than 800 nm, for example.
• the beam 4 generated by the laser 2 is from a rotatable mirror. 6 distracted.
• the mirror 6 is in this case pivotable along a rotation axis R.
• the mirror 6 can deflect the generated beam 4 along a defined horizontal scanning angle H.
• the mirror 6 is orthogonal to the horizontal scanning angle H pivotally and thus covers a vertical scanning angle V from. This allows the LIDAR device 1 a solid angle
• the generated beam 4 is at least partially reflected by the object 8 and becomes the reflected or incoming beam 10.
• the incoming beam 10 is received by a receiving unit 12.
• FIG. 2 shows a schematic representation of the receiving unit 12 of the LIDAR device 1 according to the first exemplary embodiment. To illustrate the embodiments auxiliary objects 8 are also shown.
• the receiving unit 12 is shown in an x-y plane. Through the x-y plane, the rotation axis R is orthogonal.
• the receiving unit 2 has a filter 14 which preferably allows the incoming beam 10 to pass through and blocks stray light or interfering reflections. Since a transmission range of such filters 14 with increasing angle of incidence towards smaller
• the filter 14 is rotatably mounted and is rotated or periodically pivoted by a piezoelectric actuator, not shown, in synchronism with the mirror 6 along a rotation axis which is parallel to the axis of rotation R.
• the filter 14 is adjusted in such a way that an incoming beam 10 hits the filter 14 as perpendicularly as possible. In this way, a narrow transmission range of the filter 14 can be selected, since an angle-dependent wavelength change of the incoming beam 10 is not or only slightly present.
• the dashed line filter 14 has no adjustment of its angle when an object 8 is arranged frontally or slightly offset from an optical axis A. For an object 8 located farther from the optical axis A, an incoming beam 10 has a larger angle of incidence ⁇ .
• the filter 14 Since the filter 14 is pivoted synchronously with the mirror 6, while the angle of incidence ⁇ is large relative to the optical axis A, For example, greater than 20 °, relative to the tracked filter 14 corresponds to the angle of incidence ⁇ , however, 0 °.
• the incoming beam 10 can thus transmit through the filter 14 and reach a receiving optical system 16.
• Receiving optical system 16 directs the incoming beam 10 onto a detector 18.
• the detector 18 registers the incoming beam 10 and provides it, for example, with a reception time and a scanning angle H, V of the mirror 6.
• FIG. 3 shows a schematic representation of the receiving unit 12 of the LIDAR device 1 according to a second embodiment.
• the receiving unit 12 has a
• adjustable filter 14 which consists of a Fabry-Perot cavity 20.
• the Fabry-Perot cavity 20 has two partially transparent mirrors 22, 24.
• Each of the partially transmissive mirrors 22, 24 consists of a glass substrate 26 and a partially transparent coating 28.
• a first partially transmissive mirror 22 is stationary and can not be misplaced.
• a second semitransparent mirror 24 is slidably disposed by an actuator, not shown.
• incoming rays 10 can pass if they have a certain wavelength relative to the cavity length 30.
• a transmission range for incoming beams 10 having a particular wavelength can be generated. For example
• FIG. 4 is a schematic representation of the receiving unit 12 of FIG.
• the receiving unit 12 has a fan 32, which can cool the Fabry-Perot cavity 20. Furthermore, the fan 32 is a heating element 34 for heating the generated by the fan 32
• the arrows illustrate the air flow generated by the fan 32.
• a temperature of the partially permeable Mirror 22, 24 set by the pressurizing air flow is set by the pressurizing air flow.
• partially transparent mirrors 22, 24 are acted upon by the temperature of the air flow. As a result, a density of the fluid or the
• Components of the Fabry-Perot cavity 20 are dependent on the density, can be adjusted by changing the temperature of the refractive index.
• the transmission range of the Fabry-Perot cavity 20 can be adjusted by adjusting the temperature or adapted to an incoming beam 10.
• FIGS. 5a and 5b show a schematic representation of
• the receiving unit 12 is rotatably mounted integral with the axis of rotation R and may correspond to the deflection of the mirror 6 and thus according to an incident angle ß of the incoming beam 10 are tracked by an actuator, not shown.
• FIG. 6 shows a schematic representation of the receiving unit 12 of the LIDAR device 1 according to a fifth exemplary embodiment.
• the receiving unit 12 has three stationary filters 14.
• the filters 14 are arranged at a relative angle to each other.
• the filters 14 are arranged approximately semicircular with the axis of rotation R as a center. As a result, incoming beams 10 have a small relative
• FIG. 7 is a schematic representation of the receiving unit 12 of
• the receiving unit 12 has a filter 14 which has a curvature.
• the filter 14 is made in one piece and has a curvature such that incoming beams 10 have a relative angle of incidence ⁇ of 0 ° relative to the filter 14.

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• 2017
  • 2017-04-04 DE DE102017205685.1A patent/DE102017205685A1/de active Pending
• 2018
  • 2018-03-27 US US16/499,918 patent/US11531091B2/en active Active
  • 2018-03-27 JP JP2019554636A patent/JP6941182B2/ja active Active
  • 2018-03-27 WO PCT/EP2018/057777 patent/WO2018184915A1/de unknown
  • 2018-03-27 EP EP18713908.4A patent/EP3607342A1/de active Pending
  • 2018-03-27 CN CN201880023434.XA patent/CN110520752A/zh active Pending

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