Patent Description:
The solid-state Lidar system may be mounted on a vehicle to detect objects in the environment surrounding the vehicle and to detect distances of those objects for environmental mapping. The output of the solid-state Lidar system may be used, for example, to autonomously or semi-autonomously control operation of the vehicle, e.g., propulsion, braking, steering, etc. Specifically, the system may be a component of or in communication with an advanced driver-assistance system (ADAS) of the vehicle.

Since the solid-state Lidar system is fixed in place relative to the vehicle, ride-height and/or angle of the vehicle can change the aim of the field of view. The ride-height and/or angle of the vehicle may change, e.g., from changes in weight and/or center of gravity. This may be caused by, for example, varying weight, location, and/or age of occupants, varying weight and/or location of cargo, changes in an active-suspension system of the vehicle, changes in an active-ride-handling system of the vehicle, etc. Difficulties can arise in properly aiming the vertically-narrow field of view during such changes in the vehicle and over the lifetime of the vehicle.

Document <CIT> discloses an active illumination 3D imaging system with a range camera operable to determine distances to features in a scene. The system comprises an illumination system and an imaging system simultaneously controllable to provide a field of illumination and a field of view that coincide and are substantially coextensive with a region of interest in a portion of the scene an track the region of interest as its moves. Both the field of illumination and the field of view are moved at the same time to track region of interest.

With reference to the Figures, wherein like numerals indicate like parts throughout the several views, a system <NUM> is generally shown. Specifically, the system <NUM> is a light detection and ranging (Lidar) system <NUM>. The system <NUM> includes a light emitter <NUM> that emits light into a field of illumination FOI and a photodetector <NUM> that has a field of view FOV that overlaps the field of illumination FOI. For the purpose of this disclosure "photodetector" includes a single photodetector or an array of photodetectors (including 1D arrays, 2D arrays, etc). The system <NUM> detects the emitted light that is reflected by an object in the fields of view, e.g., pedestrians, street signs, vehicles, etc..

The system <NUM> independently adjusts the vertical and/or horizontal aim of the field of illumination FOI and the vertical aim of the field of view FOV to align the field of illumination FOI and the field of view FOV. This alignment may be performed repeatedly and in the field, i.e., during use of the system <NUM>, such that the system <NUM> can recalibrate the relative positions of the field of illumination FOI and field of view FOV in the field, e.g., before, during, and/or after operation. For example, the system <NUM> may be mounted on a vehicle <NUM> and the alignment of the field of illumination FOI and the field of view FOV may be performed at any suitable time, e.g., before, during, and/or after operation of the vehicle <NUM>. As examples, changes in the ride-height and/or angle of the vehicle <NUM> may be caused by changes in weight, center of gravity of the vehicle <NUM>. This may be cause by, for example, varying weight, location, and/or age of occupants, varying weight and/or location of cargo, changes in an active-suspension system of the vehicle <NUM>, changes in an active-ride-handling system of the vehicle <NUM>, etc. In such an event, the field of view FOV may be adjusted to a desired vertical position, and the field of illumination FOI may be independently adjusted to align the field of illumination FOI with the field of view FOV. Specifically, due to the requirement of a high-resolution Lidar system, the height of the vertical aim of the field of view FOV may be limited, and the system <NUM> allows for adjustment of the vertical aim of the system <NUM>. This improves the system requirements on the field of view FOV. The system <NUM> adjusts the field of illumination FOI to align with the field of view FOV.

In the examples shown in <FIG>, the system <NUM> includes a casing <NUM>. The light emitter <NUM> is stationary relative to the casing <NUM>. A beam-steering device <NUM> is configured to adjustably reflect light from the light emitter <NUM> into the field of illumination FOI. The photodetector <NUM> is pivotally supported by the casing <NUM>. An actuator <NUM> is between the casing <NUM> and the photodetector <NUM> and is configured to pivot the photodetector <NUM> relative to the casing <NUM>, i.e., to vertically adjust the photodetector <NUM>. For example, the system <NUM> may include a housing <NUM> that supports the photodetector <NUM> and is movable relative to the casing <NUM>, and the actuator <NUM> moves the housing <NUM> relative to the casing <NUM>.

The system <NUM> is shown in <FIG> as being mounted on a vehicle <NUM>. In such an example, the system <NUM> is operated to detect objects in the environment surrounding the vehicle <NUM> and to detect distance of those objects for environmental mapping. The output of the system <NUM> may be used, for example, to autonomously or semi-autonomously control operation of the vehicle <NUM>, e.g., propulsion, braking, steering, etc. Specifically, the system <NUM> may be a component of or in communication with an advanced driver-assistance system <NUM> (ADAS) of the vehicle <NUM>. The system <NUM> may be mounted on the vehicle <NUM> in any suitable position (as one example, the system <NUM> is shown on the front of the vehicle <NUM> and directed forward). The vehicle <NUM> may have more than one system <NUM> and/or the vehicle <NUM> may include other object detection systems, including other Lidar systems. The vehicle <NUM> is shown in <FIG> as including a single system <NUM> aimed in a forward direction merely as an example. The vehicle <NUM> shown in the Figures is a passenger automobile. As other examples, the vehicle <NUM> may be of any suitable manned or un-manned type including a plane, satellite, drone, watercraft, etc..

The system <NUM> may be a solid-state Lidar system. In such an example, the system <NUM> is stationary relative to the vehicle <NUM>. For example, the casing <NUM> that is fixed relative to the vehicle <NUM>, i.e., does not move relative to the component of the vehicle to which the casing <NUM> is attached, and a silicon substrate of the system <NUM> is supported by the casing <NUM>.

As a solid-state Lidar system, the system <NUM> may be a Flash Lidar system. In such an example, the system <NUM> emits pulses of light into the field of illumination FOI. More specifically, the system <NUM> may be a 3D Flash Lidar system that generates a 3D environmental map of the surrounding environment, as shown in part in <FIG>. An example of a compilation of the data into a 3D environmental map is shown in the field of view FOV and the field of illumination FOI in <FIG>.

With reference to <FIG>, the system <NUM> includes a controller <NUM>, i.e., a computer, in communication with the light emitter <NUM> and the photodetector <NUM>. The light emitter <NUM> is a component of a light source <NUM> of the system <NUM>, and the photodetector <NUM> is a component of a receiving unit <NUM> of the system <NUM>. The system <NUM> may include any suitable number of light sources and receiving units, i.e., one or more in the casing <NUM>.

The controller <NUM> may be a microprocessor-based controller or field programmable gate array (FPGA) implemented via circuits, chips, and/or other electronic components. In other words, the controller <NUM> is a physical, i.e., structural, component of the system <NUM>. For example, the controller <NUM> may include a processor, memory, etc. The memory of the controller <NUM> may store instructions executable by the processor, i.e., processor-executable instructions, and/or may store data. The controller <NUM> may be in communication with a communication network of the vehicle <NUM> to send and/or receive instructions from the vehicle <NUM>, e.g., components of the ADAS.

As described further below, the controller <NUM> (as shown in <FIG>) communicates with the light source <NUM> and the photodetector <NUM>. Specifically, the controller <NUM> instructs the light source <NUM> to emit light and substantially simultaneously initiates a clock. When the light is reflected, i.e., by an object in the first field of view FOV, the photodetector <NUM> detects the reflected light and communicates this detection to the controller <NUM>, which the controller <NUM> uses to identify object location and distance to the object (based time of flight of the detected photon using the clock initiated at the emission of light from the light source <NUM>). The controller <NUM> uses these outputs from the photodetector <NUM> to create the environmental map and/or communicates the outputs from the photodetector <NUM> to the vehicle <NUM>, e.g., components of the ADAS, to create the environmental map. Specifically, the controller <NUM> continuously repeats the light emission and detection of reflected light for building and updating the environmental map.

The light source <NUM> emits light into the field of illumination FOI for detection by the photodetector <NUM> when the light is reflected by an object in the field of view FOV, as shown in <FIG>. With reference to <FIG>, <FIG>, and <FIG>, the light source <NUM> may include the light emitter <NUM>. For example, the light emitter <NUM> may be a laser. The light emitter <NUM> may be, for example, a semiconductor laser. In one example, the light emitter <NUM> is a vertical-cavity surface-emitting laser (VCSEL). As another example, the light emitter <NUM> may be a diode-pumped solid-state laser (DPSSL). As another example, the light emitter <NUM> may be an edge emitting laser diode. The light source <NUM> may be designed to emit a pulsed flash of light, e.g., a pulsed laser light. Specifically, the light emitter <NUM>, e.g., the VCSEL or DPSSL or edge emitter, is designed to emit a pulsed laser light. The light emitted by the light emitter <NUM> may be, for example, infrared light. Alternatively, the light emitted by the light emitter <NUM> may be of any suitable wavelength.

With continued reference to <FIG>, <FIG>, and <FIG>, the light source <NUM> may include the beam-steering device <NUM>. A "beam-steering device" is a structural component of a Lidar system. The beam-steering device <NUM> is controlled by the controller <NUM>, i.e., the controller <NUM> instructs the beam-steering device <NUM> to move to adjust the field of illumination FOI. Light is reflected by the beam-steering device <NUM> into the field of illumination FOI. As set forth above, the beam-steering device <NUM> adjustably reflects the light emitted from the light emitter <NUM>. In other words, a position of the beam-steering device <NUM> is adjusted to adjust the position of the field of illumination FOI. The adjustment of the beam-steering device <NUM> may include a vertical component and/or a horizontal component.

As one example, the beam-steering device <NUM> includes an active mirror <NUM>, i.e., a movable mirror, that is adjustable to aim light from the light emitter <NUM> into the field of illumination FOI. In other words, the light emitter <NUM> (and potentially other components of the light source <NUM>) is positioned to emit light at the active mirror <NUM> directly from the light emitter <NUM> or indirectly from the light emitter <NUM> through intermediate components.

Specifically, the active mirror <NUM> may be a micromirror. For example, the beam-steering device <NUM> may be a micro-electro-mechanical systems (MEMS) mirror. As an example, the beam-steering device <NUM> may be a digital micromirror device (DMD). The MEMS mirror may include one mirror or may include an array of mirrors that are capable of being tilted to deflect light. As another example, the MEMS mirror may include one or more mirrors each on a gimbal that is tilted, e.g., by application of voltage.

In addition to or in the alternative to the MEMS mirror, the beam-steering device <NUM> may include a diffuser. As another example, the beam-steering device <NUM> may be a liquid-crystal solid-state device, which can steer the light beam through a change in index of refraction due to an applied voltage.

The field of illumination FOI is the area exposed to light that is emitted from the light source <NUM>. In one example, as shown in <FIG>, the field of illumination FOI may be smaller than the field of view FOV. Alternatively, the field of illumination FOI may be larger than the field of view FOV or the field of illumination FOI and the field of view FOV may substantially match ("substantially match" is based on manufacturing capabilities and tolerances of the light source <NUM> and the photodetector <NUM>). As set forth above, the field of illumination FOI overlaps the field of view FOV, and vice-versa. In other words, as least part of the field of view FOV and at least part of the Field of illumination FOI occupy the same space such that an object in the overlap will reflect light from the field of illumination FOI back to the photodetector <NUM>.

As set forth above, the system <NUM> aligns the field of view FOV and the field of illumination FOI. In other words, the system <NUM> positions the field of view FOV and the field of illumination FOI to a desired relative position, vertically and optionally horizontally. As one example, the field of view FOV and the field of illumination FOI are "aligned" when positioned such that the maximum intensity of reflected light in the field of view FOV is detected by the photodetector <NUM>. The field of view FOV and the field of illumination FOI may be centered to the positions that provide the maximum detected intensity. As another example, the field of illumination FOI and the field of view FOV may be centered in order to optimize the horizon at the desired level of the scene.

With continued reference to <FIG>, <FIG>, and <FIG>, in addition to the beam-steering device <NUM>, the light source <NUM> may include any suitable number of stationary mirrors and/or diffusers in the casing <NUM> that direct light. In the example shown in <FIG>, the light beams are emitted from the system <NUM> to flash the entire field of illumination FOI. As another example, the light beams are emitted from the system <NUM> as horizontal lines and, in such an example, the beam-steering device <NUM>, the stationary mirrors, and/or the diffusers may emit the light as the horizontal beam.

Three examples of the light source <NUM> are shown in <FIG>, <FIG>, and <FIG>, respectively, and common numerals are used to identify common features in the Figures. The three examples show various arrangements of the light source <NUM>. These three examples are provided as examples, and the system <NUM> may have any suitable light source <NUM>.

With reference to <FIG>, the light emitter <NUM> is positioned in a bottom front corner of the casing <NUM> and is aimed at a stationary mirror <NUM>. The stationary mirror <NUM> is stationary relative to the casing <NUM>, i.e., is passive. The stationary mirror <NUM> reflects the light from the light emitter <NUM> to the beam-steering device <NUM>. The beam-steering device <NUM> reflects the light through two diffusers <NUM>, <NUM> and into the field of illumination FOI. The diffusers <NUM>, <NUM> are stationary relative to the casing <NUM>.

In the example shown in <FIG>, the light emitter <NUM> is positioned in a bottom rear corner of the casing <NUM> and is aimed at a stationary mirror <NUM>. The stationary mirror <NUM> is stationary relative to the casing <NUM>, i.e., is passive. The stationary mirror <NUM> reflects light from the light emitter <NUM> to the beam-steering device <NUM>. The beam-steering device <NUM> reflects the light through a diffuser <NUM> and into the field of illumination FOI. Specifically, the beam-steering device <NUM> steers the light vertically and horizontally based on the position of the beam-steering device <NUM>. The diffuser <NUM> is stationary relative to the casing <NUM>.

In the example shown in <FIG> and <FIG>, the system <NUM> includes a second light source <NUM> and a second photodetector <NUM>. Specifically, the system <NUM> in <FIG> and <FIG> includes a second light emitter <NUM> and a second beam-steering device <NUM>. The second photodetector <NUM> supported by the housing <NUM>, i.e., is movable with the housing <NUM> relative to the casing <NUM> as a unit. In the example shown in <FIG> and <FIG>, the light emitter <NUM>, photodetector <NUM>, and beam-steering device <NUM> may be in mirror-image positions of the second light emitter <NUM>, the second photodetector <NUM>, and the second beam-steering device <NUM>, respectively, about the horizontal axis A.

The second light emitter <NUM> is stationary relative to the casing <NUM> and the second beam-steering device <NUM> is configured to direct light from the second light emitter <NUM> into a second field of illumination. The second photodetector <NUM> is pivotally supported by the housing <NUM> and has a second field of view overlapping the second field of illumination. In other words, the second photodetector <NUM> detects light that was emitted by the second light emitter <NUM> and reflected by an object in the second field of view. The field of view FOV and field of illumination FOI may be different than the second field of view and second field of illumination, respectively. As an example, the field of view FOV/field of illumination FOI may be shorter and/or wider than the second field of view/field of illumination FOI, e.g., for short-range and long-range detection.

With continued reference to <FIG> and <FIG>, since both the photodetector <NUM> and the second photodetector <NUM> are supported by the housing <NUM>, movement of the housing <NUM> relative to the casing <NUM> simultaneously moves both the field of view FOV of the photodetector <NUM> and the field of view FOV of the second photodetector <NUM>, i.e., the second field of view. The beam-steering device <NUM> and the second beam-steering device <NUM> may be independently operable such that the beam-steering device <NUM> aligns the field of illumination FOI with the field of view FOV and such that the second beam-steering device <NUM> aligns the second field of illumination with the second field of view. Specifically, the beam-steering device <NUM> and the second beam-steering device <NUM> independently steer the respective light beams vertically and horizontally based on the position of the beam-steering device <NUM>.

With reference to <FIG>, the light emitter <NUM> is positioned at a bottom corner of the casing <NUM> and the second light emitter <NUM> is positioned at a top corner of the casing <NUM>. The light source <NUM> in <FIG> may have the same arrangement as shown in the top views of <FIG> or <FIG>, and the second light source <NUM> may have a mirror-image arrangement. For example, light from the light emitter <NUM> may be reflected from the beam-steering device <NUM> to a diffuser <NUM> and light from the second light emitter <NUM> may be reflected from the second beam-steering device <NUM> to a second diffuser <NUM>. Light from the diffuser <NUM> and the second diffuser <NUM> goes through a common diffuser <NUM> to the field of illumination FOI and second field of illumination, respectively.

The receiving unit <NUM> includes the photodetector <NUM> and may include receiving optics <NUM>. The photodetector <NUM> may be, for example, an avalanche photodiode detector or PIN detector. As one example, the photodetector <NUM> may be a single-photon avalanche diode (SPAD). The field of view FOV is the area in which reflected light may be sensed by the photodetector <NUM>. Light reflected in the field of view FOV is reflected to receiving optics <NUM>. The receiving optics <NUM> may include any suitable number of lenses, filters, etc..

With reference to <FIG>, the casing <NUM> may, for example, enclose the other components of the system <NUM> and may include mechanical attachment features to attach the casing <NUM> to the vehicle <NUM> and electronic connections to connect to and communicate with electronic systems of the vehicle <NUM>, e.g., components of the ADAS. The casing <NUM>, for example, may be plastic or metal and may protect the other components of the system <NUM> from environmental precipitation, dust, etc. The system <NUM> may be a unit. In other words, the light source <NUM>, the photodetector <NUM>, and the system <NUM> controller <NUM> may be supported by casing <NUM>.

Specifically, the light emitter <NUM> is stationary relative to the casing <NUM>. In other words, the light emitter <NUM> does not move relative to the casing <NUM> during operation of the system <NUM>. The light emitter <NUM> may be mounted to the casing <NUM> in any suitable fashion such that the light emitter <NUM> and the casing <NUM> move together as a unit.

The system <NUM> includes a heat sink <NUM> on the casing <NUM> adjacent the light emitter <NUM>. The heat sink <NUM> may include, for example, a wall <NUM> adjacent the light emitter <NUM> and fins <NUM> extending away from the wall <NUM> exterior to the casing <NUM> for dissipating heat away from the light emitter <NUM>. The wall <NUM> and/or fins <NUM>, for example, may be material with relatively high heat conductivity. The light emitter <NUM> may, for example, abut the wall <NUM> to encourage heat transfer. The first light emitter <NUM> and second light emitter <NUM> may also include additional cooling methods, e.g. thermal electric coolers TEC.

The stationary mirrors and diffusers are supported by the casing <NUM>. Specifically, the stationary mirrors and diffusers are stationary relative to the casing <NUM>. The stationary mirrors and diffusers may be mounted to the casing <NUM> in any suitable fashion so as to move with the casing <NUM> as a unit.

The beam-steering device <NUM> is supported by the casing <NUM>. In the example in which the beam-steering device <NUM> includes a micromirror, the micromirror may be movable relative to the casing <NUM> to direction the reflection of the light emitted from the light emitter <NUM>.

As set forth above, the housing <NUM> supports the photodetector <NUM>, <NUM> and is pivotally supported by the casing <NUM> for pivoting (i.e., tilting, swiveling, etc.) the photodetector <NUM>, <NUM>. Specifically, the housing <NUM> may be pivotally engaged with the casing <NUM>, i.e., directly in contact with the housing <NUM>, or may be coupled to the housing <NUM> through an intermediate component. The photodetector <NUM>, <NUM> is stationary relative to the housing <NUM>, i.e., moves as a unit with the housing <NUM>, such that the housing <NUM> can be pivoted relative to the casing <NUM> to adjust the field of view FOV of the photodetector <NUM>, <NUM>.

The housing <NUM> is pivotable relative to the casing <NUM> about a horizontal axis A, i.e., can swivel, tilt, etc., about the horizontal axis A. Specifically, horizontal pivot points <NUM>, i.e., pivot points <NUM> that allow for pivoting about a horizontal axis A, connect the housing <NUM> to the casing <NUM>. The horizontal pivot points <NUM> are spaced from each other along a horizontal axis A. The casing <NUM> and/or the housing <NUM> may include brackets <NUM> that support the horizontal pivot points <NUM>. The housing <NUM> may be horizontally fixed to the casing <NUM>, i.e., does not move relative to the casing <NUM> about a vertical axis. As another example, the housing may be movable relative to the casing about a vertical axis to horizontally selectively steer the field of illumination FOI, and in such an example, the housing may be moveble through a fixed range of angles, e.g., less than <NUM>°. In other words, system <NUM> is not a <NUM> ° scanning system.

The actuator <NUM> is between the housing <NUM> and the casing <NUM> for pivoting the housing <NUM> relative to the casing <NUM>. For example, the actuator <NUM> may be fixed to the casing <NUM> and the housing <NUM> to move the casing <NUM> and the housing <NUM> relative to each other about the horizontal pivot points <NUM>.

The actuator <NUM> may be, for example, an electric motor. As one example, the motor may include a base <NUM> fixed to one of the casing <NUM> and the housing <NUM> and a plunger <NUM> fixed to the other of the casing <NUM> and the housing <NUM>. The motor may be powered to retract the plunger <NUM> into the base <NUM> or extend the plunger <NUM> from the base <NUM> to move the housing <NUM> relative to the casing <NUM>. In such an example, the actuator <NUM> is spaced from the horizontal pivot points <NUM> such that force exerted between the casing <NUM> and the housing <NUM> by the actuator <NUM> moves the casing <NUM> and the housing <NUM> about the horizontal pivot points <NUM>. As another example, the motor may provide a rotary input to the housing <NUM>. For example, the motor may be between the housing <NUM> and the casing <NUM> at one or both horizontal pivot points <NUM> and may exert a rotational force at the pivot point to rotate the housing <NUM> relative to the casing <NUM>.

As set forth above, the controller <NUM> is schematically shown in <FIG>. The controller <NUM>, i.e., the processor of the controller <NUM>, is programmed to execute instructions stored in memory of the controller <NUM>. Two example methods performed by the controller <NUM> are in <FIG> and <FIG>.

The controller <NUM> is programmed to receive indication that the field of view FOV needs adjustment. It is detected that the field of view FOV is vertically offset from a horizontal position, e.g., horizon, to a degree that the field of view FOV needs to be readjusted. As an example, the field of view FOV may change when the ride-height and/or angle of the vehicle <NUM> change, as described above. In response to such an indication, the controller <NUM> adjusts the position of the photodetector <NUM>. The controller <NUM> pivots the photodetector <NUM> to vertically position the field of view FOV to a desired position, e.g., to a horizontal position. Specifically, the controller <NUM> may pivot the housing <NUM> relative to the casing <NUM>, which adjusts the field of view FOV of the photodetector <NUM> because the photodetector <NUM> moves as a unit with the housing <NUM>. For example, the controller <NUM> may be programmed to power the actuator <NUM> to pivot the housing <NUM>. In the example in which the actuator <NUM> is the motor, the actuator <NUM> may be powered to extend or retract the plunger <NUM> to move the housing <NUM> relative to the casing <NUM>.

After adjustment of the field of view FOV, the field of illumination FOI is adjusted to align the field of view FOV and the field of illumination FOI. In other words, the beam-steering device <NUM> is adjusted in response to adjustment of the field of view FOV to align the field of view FOV and the field of illumination FOI. Specifically, the field of illumination FOI may be adjusted vertically and/or horizontally to align the field of view FOV and the field of illumination FOI.

Specifically, the controller <NUM> is programmed to activate the light emitter <NUM>, i.e., to instruct the light emitter <NUM> to emit light. Similarly, with reference to the example in <FIG>, the controller <NUM> is programmed to activate the second light emitter <NUM>. The controller <NUM> may activate the light emitter <NUM> and the second light emitter <NUM> independently or dependently and may activate the light emitter <NUM> and the second light emitter <NUM> simultaneously or at different times.

The controller <NUM> is programmed to receive data from the photodetector <NUM> indicating detection of light from the light emitter <NUM> that was reflected by an object in a field of view FOV of the photodetector <NUM>. Similarly, in the example shown in <FIG>, the controller <NUM> is also programmed to receive data from the second photodetector <NUM> indicating detection of light from the second light emitter <NUM> that was reflected by an object in the field of view FOV of the second photodetector <NUM>, i.e., the second field of view.

After the position of the photodetector <NUM> has been set for the new vehicle position (e.g., in block <NUM> in <FIG> as described below), the controller <NUM> is programmed to adjust the beam-steering device <NUM> and/or the position of the photodetector <NUM> to align the field of illumination FOI with the field of view FOV, i.e., adjusting the vertical positions of the field of view FOV and/or the vertical and/or horizonal position of the field of illumination FOI to align the field of view FOV and the field of illumination FOI. As one example, the controller <NUM> may set the position of the field of view FOV and adjust the field of illumination FOI (vertically adjustment and/or horizontal adjustment) to align the two. In addition to adjusting the beam-steering device <NUM> in such an example, the controller <NUM> may adjust the position of the photodetector <NUM>, e.g., +/- a predetermined angle from the position setting in block <NUM> in <FIG>, to align the field of view FOV with the field of illumination FOI. This predetermined angle may be based on acceptable deviation from the horizontal position set in block <NUM> in <FIG>.

In the example where the beam-steering device <NUM> is the micro-electro-mechanical systems mirror, the controller <NUM> is programmed to adjust the voltage supplied to the micro-electro-mechanical systems mirror to adjust the vertical and/or horizontal position of the field of illumination FOI. Specifically, the change in voltage turns the active mirror <NUM>, e.g., about a gimbal, to adjust the position of the field of illumination FOI.

As set forth above, the alignment of the field of view FOV and the field of illumination FOI may be based on maximum detection of reflected light on an object in the field of view FOV. In other words, the controller <NUM> is programmed to adjust the beam-steering device <NUM> (vertically and//or horizontally) and the photodetector <NUM> to align the field of view FOV and the field of illumination FOI to the position that provides the maximum intensity of light reflected by an object in the field of view FOV.

In such an example, the controller <NUM> is programmed to identify changes in intensity of light reflected by an object in the field of view FOV as the beam-steering device <NUM> and/or photodetector <NUM> are adjusted. As an example, the controller <NUM> may be programmed to set the position of the field of view FOV and scan through various vertical and/or horizontal positions of the field of illumination FOI to identify the position of the field of view FOV that provides the maximum intensity of detected reflections. In the example in which the position of the photodetector <NUM> is also adjusted to align the field of view FOV and the field of illumination FOI, the field of view FOV may be set to several other positions and controller <NUM> scans through the various vertical positions of the field of illumination FOI at each of these positions of the field of view FOV. In addition to scanning through the various vertical positions of the field of illumination FOI, the controller <NUM> may scan through various horizontal positions of the field of illumination FOI. During the scanning of the various vertical positions of the field of view FOV and the various vertical and/or horizontal positions of the field of illumination FOI, the combination of position of the field of view FOV (i.e., the vertical position) and the position of the field of illumination FOI (the vertical and/or horizontal positions) that provide the maximum illumination of reflections in the field of view FOV may be identified. In other words, the controller <NUM> is programmed to determine the position of the beam-steering device <NUM> and the photodetector <NUM> that provide the maximum intensity of light reflected by an object in the field of view FOV. Once these positions are identified, the processor is programmed to adjust the beam-steering device <NUM> and the photodetector <NUM> to these positions, i.e., to center the field of illumination FOI on the field of view FOV based on the changes in intensity.

A method <NUM> of operating the examples shown in <FIG> is shown in <FIG>. The controller <NUM> may be programmed to perform the method shown in <FIG>.

In block <NUM>, the method includes receiving an indication that the field of view FOV needs vertical adjustment. As set forth above, the field of view FOV needs to be adjusted when the field of view FOV is vertically offset from a horizontal position, e.g., the horizon, to a degree that the field of view FOV needs to be readjusted. The detection that the field of view FOV needs vertical adjustment may be made by the system <NUM> itself and/or by other components of the vehicle <NUM>, e.g., components that monitor ride characteristics of the vehicle <NUM>.

In block <NUM>, the method includes, in response the indication that the field of view FOV needs vertical adjustment, adjusting the position of the photodetector <NUM>. Block <NUM> includes pivoting the housing <NUM> relative to the casing <NUM>, which adjusts the field of view FOV of the photodetector <NUM> because the photodetector <NUM> moves as a unit with the housing <NUM>. Specifically, the method includes powering the motor to extend or retract the plunger <NUM> to move the housing <NUM> relative to the casing <NUM>. The system <NUM> itself may determine the desired position to be set in block <NUM> and/or the desired position may be based on data and/or instruction from other components of the vehicle <NUM>.

The method includes activating a light emitter <NUM>, receiving data from the photodetector <NUM> indicating detection of light from the light emitter <NUM> that was reflected by an object in a field of view FOV, and adjusting the beam-steering device <NUM> to ( vertically and/or horizontally) align the field of view FOV with the field of illumination FOI. Specifically, in blocks <NUM>, <NUM>, and <NUM>, the method includes setting the position of the field of view FOV and scanning through various positions of the field of illumination FOI. This data is used to identify the position of the field of view FOV that provides the maximum intensity of detected reflections.

In decision block <NUM>, the method includes determining whether the scan in blocks <NUM>, <NUM>, and <NUM> is to be repeated for another position of the photodetector <NUM>. As set forth above, the photodetector <NUM> may be adjusted within a predetermined acceptable deviation from the position set in block <NUM>. In such an example, the method may repeat blocks <NUM>, <NUM>, and <NUM> for a predetermined number of sample angles, i.e., if the answer is yes in block <NUM>. In other words, the method may include scanning several positions of the photodetector <NUM> at several positions of the beam-steering device <NUM>. If blocks <NUM>, <NUM>, and <NUM> are to be repeated, block <NUM> includes adjusting the position of the photodetector <NUM> before block <NUM> is performed again.

If the answer is no in decision block <NUM>, the method includes determining the position of the beam-steering device <NUM> and/or the photodetector <NUM> that provide the maximum intensity reflection. In block <NUM>, the method includes adjusting the beam-steering device <NUM> (i.e., vertically and/or horizontally) and/or the position of the photodetector <NUM> (i.e., vertically) to the position that provides the maximum intensity reflection.

A method <NUM> of operating the example shown in <FIG> is shown in <FIG>. The controller <NUM> may be programmed to perform the method shown in <FIG>. Similar to blocks <NUM> and <NUM> in <FIG> and described above, the block <NUM> includes receiving an indication that the field of view FOV needs adjustment and block <NUM> includes adjusting the position of the photodetector <NUM> to a desired position in response the indication that the field of view FOV needs vertical adjustment.

Similar to blocks <NUM>, <NUM>, and <NUM> in <FIG>, blocks <NUM>, <NUM>, and <NUM> include setting the position of the field of view FOV (i.e., the vertical position) and scanning through various positions of the field of illumination FOI (i.e., vertical position and/or horizontal position). This data is used to identify the position of the field of view FOV that provides the maximum intensity of detected reflections. Similarly, blocks <NUM>, <NUM>, and <NUM> perform the same steps for the second field of view and second field of illumination. In other words, the method <NUM> includes setting the position of the second photodetector <NUM> and scanning through various positions of the second beam-steering device <NUM> (i.e., vertical and/or horizontal positions).

Claim 1:
A system (<NUM>) comprising:
a casing (<NUM>);
a light emitter (<NUM>) stationary relative to the casing (<NUM>);
a beam-steering device (<NUM>) configured to adjustably reflect light from the light emitter (<NUM>) into a field of illumination (FOI);
a photodetector (<NUM>) pivotally supported by the casing (<NUM>) and having a field of view (FOV) overlapping the field of illumination (FOI);
an actuator (<NUM>) between the casing (<NUM>) and the photodetector (<NUM>) and configured to pivot the photodetector (<NUM>) relative to the casing (<NUM>);
a controller (<NUM>) programmed to:
receive an indication that the field of view (FOV) needs adjustment when the field of view (FOV) is vertically offset from a horizontal position,
adjust the position of the photodetector (<NUM>) to vertically position the field of (FOV) to a desired position,
adjust the field of illumination (FOI) to align the field of illumination (FOI) with the field of view (FOV).