FOCAL PLANE ARRAY

In some implementations, a light blocking material may be applied to a photodetector comprising a microlens array (MLA) component and a photodiode array (PDA) component. The light blocking material may be applied to a first distal end of the MLA component and a second distal end of the MLA component.

BACKGROUND

An autonomous vehicle (or AV) is a vehicle having a processor, programming instructions, and drivetrain components that are controllable by the processor without requiring a human operator. An autonomous vehicle may be fully autonomous in that the autonomous vehicle does not require a human operator for most or all driving conditions and functions, or an autonomous vehicle may be semi-autonomous in that a human operator may be required in certain conditions or for certain operations, or that a human operator may override the autonomous vehicle's autonomous system and may take control of the autonomous vehicle.

SUMMARY

In some implementations, a photodetector includes a microlens array (MLA) component; a photodiode array (PDA) component; and light blocking material applied at a first distal end of the MLA component, and a second distal end of the MLA component.

In some implementations, a method includes attaching a photodetector to an interposer, the photodetector comprising: an MLA component, and a PDA component; applying a light blocking material to a first distal end of the MLA component; and applying the light blocking material to a second distal end of the MLA component.

In some implementations, a lidar system includes a photodetector, comprising: an MLA component, a PDA component, and light blocking material applied at a first distal end of the MLA component, and a second distal end of the MLA component; a memory; and at least one processor coupled to the memory and configured to: receive input from the photodetector; and generate a lidar point cloud based at least in part on the input.

DETAILED DESCRIPTION

The following detailed description of example implementations refers to the accompanying drawings, which are incorporated herein and form a part of the specification. The same reference numbers in different drawings may identify the same or similar elements. In general, the left-most digit(s) of a reference number identifies the drawing in which the reference number first appears.

Photodetectors, or focal plane arrays, are sensors that may be used to receive light and convert the light into electrical signals. Photodetectors may be used in a variety of contexts, including within a lidar system that may be included in an autonomous vehicle to facilitate control and navigation of the autonomous vehicle. A lidar system may emit pulses of light, receive reflected light, analyze the received light, and provide output that may be further processed or otherwise used by other systems associated with the autonomous vehicle. In some situations, stray light may be detected by a photodetector of a lidar system (e.g., due to reflections from out-of-field objects, internal lidar system components, and/or the like), which may cause the photodetector to produce output associated with unwanted stray light. For example, stray light may cause artifacts, bloom, false objects, and/or other unwanted noise in the photodetector output. Accordingly, stray light may reduce the accuracy and usefulness of the output produced by a photodetector and/or lidar system, which may lead to a variety of issues for the analysis and use of the output, including false object detection, lower object detection accuracy and/or precision, and/or the like.

Some implementations described herein prevent stray light from entering or otherwise interfering with a photodetector, or focal plane array. For example, and as described further herein, a photodetector may include a microlens array (MLA) component and a photodiode array (PDA) component, and a light blocking material may be applied at distal ends of at least the MLA component. The light blocking material may block stray light from entering the MLA and/or PDA. This may prevent the photodetector, and any associated lidar system, from sensing and producing output associated with the stray light, which may reduce, for example, unwanted coupling and the appearance of artifacts, false objects, and/or other unwanted noise in a lidar point cloud output from the lidar system. As a result, by preventing stray light from being detected by the photodetector, a lidar system (or other system receiving output from the photodetector) may have improved accuracy, fewer false object detections, higher precision, and/or the like. When used in the context of autonomous vehicles, this may lead to safer, more precise, and more accurate control, navigation, and/or collision avoidance, among other examples.

FIG.1is a diagram of an example environment100in which an autonomous vehicle may operate, in accordance with some aspects of the disclosure. The environment100may include, for example, a vehicle102, an on-board system104of the vehicle102, a remote computing device106, and/or a network108. As further shown, the environment100may include one or more objects110that the vehicle102is configured to detect.

The vehicle102may include any moving form of conveyance that is capable of carrying one or more human occupants and/or cargo and that is powered by any form of energy. The vehicle102may include, for example, a land vehicle (e.g., a car, a truck, a van, or a train), an aircraft (e.g., an unmanned aerial vehicle or a drone), or a watercraft. In the example ofFIG.1, the vehicle102is a land vehicle and is shown as a car. Furthermore, the vehicle102is an autonomous vehicle in the example ofFIG.1. An autonomous vehicle (or AV) is a vehicle having a processor, programming instructions, and drivetrain components that are controllable by the processor without requiring a human operator. An autonomous vehicle may be fully autonomous in that the autonomous vehicle does not require a human operator for most or all driving conditions and functions, or an autonomous vehicle may be semi-autonomous in that a human operator may be required in certain conditions or for certain operations, or that a human operator may override the autonomous vehicle's autonomous system and may take control of the autonomous vehicle.

As shown inFIG.1, the vehicle102may include an on-board system104that is integrated into and/or coupled with the vehicle102. In general, the on-board system104may be used to control the vehicle102, to sense information about the vehicle102and/or an environment in which the vehicle102operates, to detect one or more objects110in the proximity of the vehicle, to provide output to or receive input from an occupant of the vehicle102, and/or to communicate with one or more devices remote from the vehicle102, such as another vehicle and/or the remote computing device106. The on-board system104is described in more detail below in connection withFIG.2.

In some implementations, the vehicle102may travel along a road in a semi-autonomous or autonomous manner. The vehicle102may be configured to detect objects110in proximity of the vehicle102. An object110may include, for example, another vehicle (e.g., an autonomous vehicle or a non-autonomous vehicle that requires a human operator for most or all driving conditions and functions), a cyclist (e.g., a rider of a bicycle, electric scooter, or motorcycle), a pedestrian, a road feature (e.g., a roadway boundary, a lane marker, a sidewalk, a median, a guard rail, a barricade, a sign, a traffic signal, a railroad crossing, or a bike path), and/or another object that may be on a roadway or in proximity of a roadway, such as a tree or an animal.

To detect objects110, the vehicle102may be equipped with one or more sensors, such as a lidar system, as described in more detail elsewhere herein. The lidar system may be configured to transmit a light pulse112to detect objects110located within a distance or range of distances of the vehicle102. The light pulse112may be incident on an object110and may be reflected back to the lidar system as a reflected light pulse114. The reflected light pulse114may be incident on the lidar system and may be processed to determine a distance between the object110and the vehicle102. The reflected light pulse114may be detected using, for example, a photodetector or an array of photodetectors, which may include a focal plane array, positioned and configured to receive the reflected light pulse114. In some implementations, a lidar system may be included in another system other than a vehicle102, such as a robot, a satellite, and/or a traffic light, or may be used as a standalone system. Furthermore, implementations described herein are not limited to autonomous vehicle applications and may be used in other applications, such as robotic applications, radar system applications, metric applications, and/or system performance applications.

The lidar system may provide lidar data, such as information about a detected object110(e.g., information about a distance to the object110, a speed of the object110, and/or a direction of movement of the object110), to one or more other components of the on-board system104. Additionally, or alternatively, the vehicle102may transmit lidar data to the remote computing device106(e.g., a server, a cloud computing system, and/or a database) via the network108. The remote computing device106may be configured to process the lidar data and/or to transmit a result of processing the lidar data to the vehicle102via the network108.

The network108may include one or more wired and/or wireless networks. For example, the network108may include a wireless wide area network (e.g., a cellular network or a public land mobile network), a local area network (e.g., a wired local area network or a wireless local area network (WLAN), such as a Wi-Fi network), a personal area network (e.g., a Bluetooth network), a near-field communication network, a telephone network, a private network, the Internet, and/or a combination of these or other types of networks. The network108enables communication among the devices of environment100.

As indicated above,FIG.1is provided as an example. Other examples may differ from what is described with regard toFIG.1. The number and arrangement of devices shown inFIG.1are provided as an example. In practice, there may be additional devices, fewer devices, different devices, or differently arranged devices than those shown inFIG.1. Furthermore, two or more devices shown inFIG.1may be implemented within a single device, or a single device shown inFIG.1may be implemented as multiple, distributed devices. Additionally, or alternatively, a set of devices (e.g., one or more devices) shown inFIG.1may perform one or more functions described as being performed by another set of devices shown inFIG.1.

FIG.2is a diagram of an example on-board system200of an autonomous vehicle, in accordance with some aspects of the disclosure. In some implementations, the on-board system200may correspond to the on-board system104included in the vehicle102, as described above in connection withFIG.1. As shown inFIG.2, the on-board system200may include one or more of the illustrated components202-256. The components of the on-board system200may include, for example, a power system202, one or more sensors204, one or more controllers206, and/or an on-board computing device208. The components of the on-board system200may communicate via a bus (e.g., one or more wired and/or wireless connections), such as a controller area network (CAN) bus.

The power system202may be configured to generate mechanical energy for the vehicle102to move the vehicle102. For example, the power system202may include an engine that converts fuel to mechanical energy (e.g., via combustion) and/or a motor that converts electrical energy to mechanical energy.

The one or more sensors204may be configured to detect operational parameters of the vehicle102and/or environmental conditions of an environment in which the vehicle102operates. For example, the one or more sensors204may include an engine temperature sensor210, a battery voltage sensor212, an engine rotations per minute (RPM) sensor214, a throttle position sensor216, a battery sensor218(to measure current, voltage, and/or temperature of a battery), a motor current sensor220, a motor voltage sensor222, a motor position sensor224(e.g., a resolver and/or encoder), a motion sensor226(e.g., an accelerometer, gyroscope and/or inertial measurement unit), a speed sensor228, an odometer sensor230, a clock232, a position sensor234(e.g., a global navigation satellite system (GNSS) sensor and/or a global positioning satellite (GPS) sensor), one or more cameras236, a lidar system238, one or more other ranging systems240(e.g., a radar system and/or a sonar system), and/or an environmental sensor242(e.g., a precipitation sensor and/or ambient temperature sensor).

The one or more controllers206may be configured to control operation of the vehicle102. For example, the one or more controllers206may include a brake controller244to control braking of the vehicle102, a steering controller246to control steering and/or direction of the vehicle102, a throttle controller248and/or a speed controller250to control speed and/or acceleration of the vehicle102, a gear controller252to control gear shifting of the vehicle102, a routing controller254to control navigation and/or routing of the vehicle102(e.g., using map data), and/or an auxiliary device controller256to control one or more auxiliary devices associated with the vehicle102, such as a testing device, an auxiliary sensor, and/or a mobile device transported by the vehicle102.

The on-board computing device208may be configured to receive sensor data from one or more sensors204and/or to provide commands to one or more controllers206. For example, the on-board computing device208may control operation of the vehicle102by providing a command to a controller206based on sensor data received from a sensor204. In some implementations, the on-board computing device208may be configured to process sensor data to generate a command. The on-board computing device208may include memory, one or more processors, an input component, an output component, and/or a communication component, as described in more detail elsewhere herein.

As an example, the on-board computing device208may receive navigation data, such as information associated with a navigation route from a start location of the vehicle102to a destination location for the vehicle102. In some implementations, the navigation data is accessed and/or generated by the routing controller254. For example, the routing controller254may access map data and identify possible routes and/or road segments that the vehicle102can travel to move from the start location to the destination location. In some implementations, the routing controller254may identify a preferred route, such as by scoring multiple possible routes, applying one or more routing techniques (e.g., minimum Euclidean distance, Dijkstra's algorithm, and/or Bellman-Ford algorithm), accounting for traffic data, and/or receiving a user selection of a route, among other examples. The on-board computing device208may use the navigation data to control operation of the vehicle102.

As the vehicle travels along the route, the on-board computing device208may receive sensor data from various sensors204. For example, the position sensor234may provide geographic location information to the on-board computing device208, which may then access a map associated with the geographic location information to determine known fixed features associated with the geographic location, such as streets, buildings, stop signs, and/or traffic signals, which may be used to control operation of the vehicle102.

In some implementations, the on-board computing device208may receive one or more images captured by one or more cameras236, may analyze the one or more images (e.g., to detect object data), and may control operation of the vehicle102based on analyzing the images (e.g., to avoid detected objects). Additionally, or alternatively, the on-board computing device208may receive object data associated with one or more objects detected in a vicinity of the vehicle102and/or may generate object data based on sensor data. The object data may indicate the presence of absence of an object, a location of the object, a distance between the object and the vehicle102, a speed of the object, a direction of movement of the object, an acceleration of the object, a trajectory (e.g., a heading) of the object, a shape of the object, a size of the object, a footprint of the object, and/or a type of the object (e.g., a vehicle, a pedestrian, a cyclist, a stationary object, or a moving object). The object data may be detected by, for example, one or more cameras236(e.g., as image data), the lidar system238(e.g., as lidar data) and/or one or more other ranging systems240(e.g., as radar data or sonar data). The on-board computing device208may process the object data to detect objects in proximity of the vehicle102and/or to control operation of the vehicle102based on the object data (e.g., to avoid detected objects).

In some implementations, the on-board computing device208may use the object data (e.g., current object data) to predict future object data for one or more objects. For example, the on-board computing device208may predict a future location of an object, a future distance between the object and the vehicle102, a future speed of the object, a future direction of movement of the object, a future acceleration of the object, and/or a future trajectory (e.g., a future heading) of the object. For example, if an object is a vehicle and map data indicates that the vehicle is at an intersection, then the on-board computing device208may predict whether the object will likely move straight or turn. As another example, if the sensor data and/or the map data indicates that the intersection does not have a traffic light, then the on-board computing device208may predict whether the object will stop prior to entering the intersection.

The on-board computing device208may generate a motion plan for the vehicle102based on sensor data, navigation data, and/or object data (e.g., current object data and/or future object data). For example, based on current locations of objects and/or predicted future locations of objects, the on-board computing device208may generate a motion plan to move the vehicle102along a surface and avoid collision with other objects. In some implementations, the motion plan may include, for one or more points in time, a speed of the vehicle102, a direction of the vehicle102, and/or an acceleration of the vehicle102. Additionally, or alternatively, the motion plan may indicate one or more actions with respect to a detected object, such as whether to overtake the object, yield to the object, pass the object, or the like. The on-board computing device208may generate one or more commands or instructions based on the motion plan, and may provide those command(s) to one or more controllers206for execution.

As indicated above,FIG.2is provided as an example. Other examples may differ from what is described with regard toFIG.2. The number and arrangement of components shown inFIG.2are provided as an example. In practice, there may be additional components, fewer components, different components, or differently arranged components than those shown inFIG.2. Furthermore, two or more components shown inFIG.2may be implemented within a single components, or a single components shown inFIG.2may be implemented as multiple, distributed components. Additionally, or alternatively, a set of components (e.g., one or more components) shown inFIG.2may perform one or more functions described as being performed by another set of components shown inFIG.2. For example, although some components ofFIG.2are primarily associated with land vehicles, other types of vehicles are within the scope of the disclosure. As an example, an on-board system of an aircraft may not include the brake controller244and/or the gear controller252, but may include an altitude sensor. As another example, an on-board system of a watercraft may include a depth sensor.

FIG.3is a diagram of an example lidar system300, in accordance with some aspects of the disclosure. In some implementations, the lidar system300may correspond to the lidar system238ofFIG.2. As shown inFIG.3, the lidar system may include a housing302, a light emitter system304, a light detector system306, an optical element structure308, a motor310, and an analysis device312.

The housing302may be rotatable (e.g., by 360 degrees) around an axle314(or hub) of the motor310. The housing302may include an aperture316(e.g., an emitter and/or receiver aperture) made of a material transparent to light. Although a single aperture316is shown inFIG.3, the housing302may include multiple apertures316in some implementations. The lidar system300may emit light through one or more apertures316and may receive reflected light back through one or more apertures316as the housing302rotates around components housed within the housing302. Alternatively, the housing302may be a stationary structure (e.g., that does not rotate), at least partially made of a material that is transparent to light, with rotatable components inside of the housing302.

The housing302may house the light emitter system304, the light detector system306, and/or the optical element structure308. The light emitter system304may be configured and/or positioned to generate and emit pulses of light through the aperture316and/or through transparent material of the housing302. For example, the light emitter system304may include one or more light emitters, such as laser emitter chips or other light emitting devices. The light emitter system304may include any number of individual light emitters (e.g., 8 emitters, 64 emitters, or 128 emitters), which may emit light at substantially the same intensity or of varying intensities. The light detector system306may include a photodetector or an array of photodetectors, such as a photodiode array or focal plane array, configured and/or positioned to receive light reflected back through the housing302and/or the aperture316.

The optical element structure308may be positioned between the light emitter system304and the housing302, and/or may be positioned between the light detector system306and the housing302. The optical element structure308may include one or more lenses, waveplates, and/or mirrors that focus and direct light that passes through the optical element structure308. The light emitter system304, the light detector system306, and/or the optical element structure308may rotate with a rotatable housing302or may rotate inside of a stationary housing302.

The analysis device312may be configured to receive (e.g., via one or more wired and/or wireless connections) sensor data collected by the light detector system306, analyze the sensor data to measure characteristics of the received light, and generate output data based on the sensor data. In some implementations, the analysis device312may provide the output data to another system that can control operations and/or provide recommendations with respect to an environment from which the sensor data was collected. For example, the analysis device312may provide the output data to the on-board system104(e.g., the on-board computing device208) of the vehicle102to enable the on-board system104to process the output data and/or use the output data (or the processed output data) to control operation of the vehicle102. The analysis device312may be integrated into the lidar system300or may be external from the lidar system300and communicatively connected to the lidar system300via a network. The analysis device312may include memory, one or more processors, an input component, an output component, and/or a communication component, as described in more detail elsewhere herein.

As indicated above,FIG.3is provided as an example. Other examples may differ from what is described with regard toFIG.3. The number and arrangement of components shown inFIG.3are provided as an example. In practice, there may be additional components, fewer components, different components, or differently arranged components than those shown inFIG.3. Furthermore, two or more components shown inFIG.3may be implemented within a single components, or a single components shown inFIG.3may be implemented as multiple, distributed components. Additionally, or alternatively, a set of components (e.g., one or more components) shown inFIG.3may perform one or more functions described as being performed by another set of components shown inFIG.3.

FIG.4is a diagram depicting a side-view400of example components of a lidar system (e.g., lidar system300) with light incident thereon, in accordance with some aspects of the disclosure. As shown inFIG.4, example400depicts a microlens array (MLA)402(e.g., an optical element structure308), a photodiode array (PDA)404(e.g., a light detector system306), a standoff406between the MLA402and PDA404, an interposer component408, and other components410. The standoff406may be a component to facilitate a connection between the MLA402and PDA404, such as a polymer (e.g., a photolithographic polymer). In some aspects, the standoff406may be included in a gap, trench, or other feature(s) of the MLA402and/or PDA404that facilitates connecting the MLA402and the PDA404. The interposer component408may be any suitable component to provide mechanical support for and/or an electrical interface between the various components of the lidar system300, and the interposer408may be formed of silicon, glass, and/or an organic substrate, among other examples.

As described herein, a lidar system300may emit pulses of light, receive reflected light (e.g., via MLA and PDA), analyze the received light, and provide output that may be processed or otherwise used by other systems (e.g., in a vehicle). In some situations, light412, which may include reflected light and/or other light entering an aperture of the lidar system300, may be incident on and/or reflected by other components410of the lidar system300. This may cause stray light414to enter the MLA and/or PDA, which may cause the lidar system300to sense and produce output associated with the unwanted light. For example, some lidar systems300may produce output in the form of a lidar point cloud indicating the intensity of reflected light, and stray light414may cause artifacts, false objects, and/or other unwanted noise in the lidar point cloud output. In some lidar systems, even a single photon of unwanted stray light414may cause false objects to appear in a lidar point cloud or other output produced by the lidar system300. Accordingly, stray light414may reduce the accuracy and usefulness of the output produced by the lidar system300, which may lead to a variety of issues for the analysis and use of the output, including false object detection, lower object detection accuracy and/or precision, and/or the like.

As indicated above,FIG.4is provided as an example. Other examples may differ from what is described with regard toFIG.4. The number and arrangement of devices shown inFIG.4are provided as an example. In practice, there may be additional devices, fewer devices, different devices, or differently arranged devices than those shown inFIG.4.

FIG.5is a diagram of an example implementation500associated with blocking stray light associated with a lidar system (e.g., lidar system300), in accordance with some aspects of the disclosure. As shown inFIG.5, example implementation500depicts an MLA402(e.g., an optical element structure308), a PDA404(e.g., a light detector system306), a standoff406between the MLA402and PDA404, an interposer component408, other components410, and a light blocking material502.

In some aspects, the light blocking material502may include any material capable of blocking infrared light. For example, the light blocking material502may include a solid or viscous material. In some aspects, the light blocking material502is capable of blocking short-wave infrared light (e.g., 1400 nm to 3000 nm wavelength), among other examples. In some aspects, the light blocking material502may comprise a viscous and adhesive ultraviolet (UV) curable polymer.

In some aspects, the light blocking material502is applied to an end of the MLA402. For example, the light blocking material502may be applied on top of the MLA402and to an end face of the MLA402, as shown in the example implementation500. In some aspects, the light blocking material502may extend further in the X direction, such that the light blocking material502is applied across a top surface of the PDA404. In some aspects, the light blocking material502may not extend, in the X direction, to cover a side face of the MLA402, PDA404, and/or the standoff406, such that side faces of the MLA402, PDA404, and/or standoff406remain clear of the light blocking material502. In some aspects, the light blocking material502may extend further in the Y direction, such that the light blocking material502extends over the end face of the MLA402, the PDA404, and/or the standoff406. In some aspects, the light blocking material502may not extend in the +Y direction to come into contact with any of the other components410of the lidar system300, or in the −Y direction to cover a microlens and/or pixel region of the MLA402. In some aspects, the light blocking material502may extend further in the Z direction, such that the light blocking material502is applied to an end face of the PDA404and/or the standoff406and may further extend to the interposer408.

In some aspects, the light blocking material502may be applied to avoid covering fiducials of the MLA402, PDA404, or other components. For example, and as depicted in further detail inFIGS.6-8, various features of the MLA402and/or PDA404may be covered by the light blocking material502, while some features are left uncovered. In some aspects, the light blocking material502may be disposed within a gap between the MLA402and PDA404. For example, the MLA402and/or PDA404may include a trench or other feature that results in a gap between the MLA402and PDA404. At least a portion of the gap may be filled with the standoff406, and other portions of the gap may be filled with the light blocking material502. In some aspects, the light blocking material502within the gap may come into contact with the standoff406, preventing the light blocking material502from seeping into contact with portions of the MLA402and/or PDA404that would interfere with the functionality of the components.

In some cases, such as when the light blocking material502is a solid material, the light blocking material502may be pre-formed and attached to the MLA402and/or PDA404during or after assembly of the lidar system. For example, a solid light-blocking material502may be fastened to one or more components of the lidar system with one or more physical fasteners and/or an adhesive material, among other examples. In some cases, such as when the light blocking material502is viscous, the light blocking material502may be applied via a dispenser, brush, or other form of applicator, manually or via electro-mechanical means, during or after assembly of the lidar system. For example, the light blocking material502may be applied, starting at a top surface of the MLA402, by dragging an applicator in the +Y direction, allowing the viscous light blocking material to flow over the edge face of the MLA402and, in some aspects, over portions of the PDA404, standoff406, and/or interposer408, as described herein. In this example, the light blocking material502may be cured using UV light after it is applied.

As shown in the example embodiment500, the light blocking material502may block stray light414from entering the MLA402and/or PDA404. This may prevent the lidar system from sensing and producing output associated with the unwanted light (e.g., stray light414), which may reduce, for example, unwanted coupling and the appearance of artifacts, false objects, and/or other unwanted noise in a lidar point cloud output from the lidar system. As described herein, even a single photon of stray light414may cause false objects to appear in a lidar point cloud or other output produced by the lidar system. Accordingly, by preventing stray light414from being detected by the lidar system, the lidar system may have improved accuracy, fewer false object detections, higher precision, and/or the like. When used in the context of autonomous vehicles, this may lead to safer and more accurate control, navigation, and/or the like.

As indicated above,FIG.5is provided as an example. Other examples may differ from what is described with regard toFIG.5. The number and arrangement of devices shown inFIG.5are provided as an example. In practice, there may be additional devices, fewer devices, different devices, or differently arranged devices than those shown inFIG.5. WhileFIG.5only depicts one edge of an MLA402and PDA404, light blocking material502may also be applied to other portions of the lidar system, such as on another edge of the MLA402and/or PDA404opposite the depicted edge.

FIGS.6A-6Care diagrams of example implementations associated with application of a light blocking material to edges of an MLA402and/or PDA404, in accordance with some aspects of the disclosure. As shown in the example600ofFIG.6A, a light blocking material602is depicted as being applied to both a first distal end612and a second distal end614of an MLA402, such that the light blocking material602is on top of a portion of each end of the MLA402and flows over an edge of the MLA402, over an edge of the PDA404, and onto a portion of interposer408. As described herein, the light blocking material602may prevent unwanted stray light, such as light reflecting off of another component (e.g., component610) of the lidar system, from entering the MLA402and/or PDA404. Similarly,FIG.6Bdepicts a first light blocking material604applied to a first distal end620of the MLA402, PDA404, and interposer408, whileFIG.6Cdepicts a second light blocking material606applied to a second distal end630of the MLA402, PDA404, and interposer408. As shown inFIGS.6A-6C, the light blocking material (e.g.,602,604, and/or606) may be applied to the top of the MLA402, without covering a pixel region608of the MLA402, and flow over edge faces of the MLA402, PDA404, and on to the interposer408without coming into contact with fiducials of the various components of the lidar system.

As indicated above,FIGS.6A-6Care provided as examples. Other examples may differ from what is described with regard toFIGS.6A-6C. The number and arrangement of devices shown inFIGS.6A-6Care provided as examples. In practice, there may be additional devices, fewer devices, different devices, or differently arranged devices than those shown inFIGS.6A-6C.

FIG.7is an isometric diagram of an example implementation700associated with blocking stray light associated with a lidar system, in accordance with some aspects of the disclosure. As shown inFIG.7, example implementation700depicts an MLA402, a PDA404, an interposer component408, another component410, and a light blocking material702. In this example, the light blocking material702is depicted as being applied on top of the MLA402and flowing over the edge faces of the MLA402and the PDA404onto the interposer408. In some situations, the light blocking material may flow into a gap between the MLA402and the PDA404until it reaches a standoff or other feature between the components, further shielding the MLA402and the PDA404from stray light.

As indicated above,FIG.7is provided as an example. Other examples may differ from what is described with regard toFIG.7. The number and arrangement of devices shown inFIG.7are provided as an example. In practice, there may be additional devices, fewer devices, different devices, or differently arranged devices than those shown inFIG.7.

FIG.8is a diagram of an example end face800of an MLA and PDA, in accordance with some aspects of the disclosure. As shown inFIG.8, there are four bands, or zones, identified by numerals 1, 2, 3, and 4, which indicate portions of the lidar system components extending from a pixel region804of the MLA402in the negative Y direction. Each of the identified bands may correspond to features of one or more lidar system components that might cause reflections and stray light. Accordingly, covering one or more of the four bands with light blocking material802may facilitate the prevention of stray light from entering the MLA402and/or PDA404. As indicated, in some aspects, a center of the first band (1) may be approximately 0.13 mm (in the −Y direction) from the last pixel of the pixel region804, a center of the second band (2) may be approximately 0.38 mm (in the −Y direction) from the last pixel of the pixel region804, a center of the third band (3) may be approximately 0.62 mm (in the −Y direction) from the last pixel of the pixel region804, and a center of the fourth band (4) may be approximately 1.0 mm (in the −Y direction) from the last pixel of the pixel region804.

As indicated above,FIG.8is provided as an example. Other examples may differ from what is described with regard toFIG.8. The number and arrangement of devices shown inFIG.8are provided as an example. In practice, there may be additional devices, fewer devices, different devices, or differently arranged devices than those shown inFIG.8.

FIG.9is a diagram representing an example900point cloud output that may be produced by a lidar system. As shown inFIG.9, an example of a log10plot of a normal (e.g., not covered by light blocking material) point cloud output is shown, with the number of pixels along the X axis and a horizontal step along the Y axis. As seen in the example900, there are four artifacts (e.g., false objects, noise, and/or the like) shown and identified by numerals 1, 2, 3, and 4. In some aspects, the artifacts may correspond to stray light reflected from the bands described herein in association withFIG.8. In some aspects, the artifacts may correspond to stray light generally, with no known source.

FIG.10is a diagram representing an example1000point cloud output associated with a lidar system using light blocking material, in accordance with some aspects of the disclosure. As shown inFIG.10, an example of a log10plot of a blackened (e.g., covered by light blocking material) point cloud output is shown, with the number of pixels along the X axis and a horizontal step along the Y axis. As seen in the example1000, there is one artifact (e.g., false object, noise, and/or the like) shown and identified by numeral 1. In comparison to the plot shown inFIG.9, the example1000has significantly less noise, or artifacts, due to application of the light blocking material.

As indicated above,FIG.10is provided as an example. Other examples may differ from what is described with regard toFIG.10.

FIG.11is a flowchart of an example process1100associated with applying light blocking material to a focal plane array. In some implementations, one or more process blocks ofFIG.11are performed automatically by a device (e.g., a manufacturing device) for fabrication and/or assembly of focal plane arrays and/or lidar system components. In some implementations, one or more process blocks ofFIG.11are performed by another device or a group of devices separate from or including the device. Additionally, or alternatively, one or more process blocks ofFIG.11may be performed manually (e.g., by hand).

As shown inFIG.11, process1100may include attaching a photodetector to an interposer, the photodetector comprising an MLA component and a PDA component (block1110). For example, the device may attach a photodetector to an interposer, as described above.

As further shown inFIG.11, process1100may include applying a light blocking material to a first distal end of the MLA component (block1120). For example, the device may apply a light blocking material to a first distal end of the MLA component, as described above.

As further shown inFIG.11, process1100may include applying the light blocking material to a second distal end of the MLA component (block1130). For example, the device may apply the light blocking material to a second distal end of the MLA component, as described above.

In a first implementation, applying the light blocking material to the first distal end of the MLA component comprises applying, using an applicator, the light blocking material to a top surface of the MLA component, proximate to a pixel region between the first distal end of the MLA component and the second distal end of the MLA component, and dragging, using the applicator, at least a portion of the light blocking material toward the first distal end of the MLA component, to cause the portion of the light blocking material to cover at least a portion of an edge face of the MLA.

In a second implementation, alone or in combination with the first implementation, the light blocking material comprises UV curable polymer, and the method further comprises curing the light blocking material.

AlthoughFIG.11shows example blocks of process1100, in some implementations, process1100includes additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted inFIG.11. Additionally, or alternatively, two or more of the blocks of process1100may be performed in parallel.

Aspect 1: A photodetector, comprising: an MLA component; a PDA component; and light blocking material applied at a first distal end of the MLA component, and a second distal end of the MLA component.

Aspect 2: The photodetector of Aspect 1, wherein the MLA component is arranged on top of the PDA component.

Aspect 3: The photodetector of any of Aspects 1-2, wherein the light blocking material is applied to a first distal end of the PDA component and a second distal end of the PDA component.

Aspect 4: The photodetector of Aspect 3, wherein a first portion of the light blocking material is applied to the first distal end of the PDA component and the first distal end of the MLA component, and wherein a second portion of the light blocking material is applied to the second distal end of the PDA component and the second distal end of the MLA component. wherein a second portion of the light blocking material is applied to the second distal end of the PDA component and the second distal end of the MLA component.

Aspect 5: The photodetector of any of Aspects 1-4, wherein the light blocking material covers a portion of a top surface of the MLA and at least a portion of an edge face of the MLA.

Aspect 6: The photodetector of Aspect 5, wherein the light blocking material covers at least a portion an edge face of the PDA.

Aspect 7: The photodetector of any of Aspects 1-6, wherein the light blocking material is disposed in a gap between the MLA component and the PDA component.

Aspect 8: The photodetector of Aspect 7, wherein a portion of the light blocking material is in contact with a standoff disposed between the MLA component and the PDA component.

Aspect 9: The photodetector of Aspect 8, wherein the standoff comprises a photolithographic polymer.

Aspect 10: The photodetector of any of Aspects 1-9, wherein the light blocking material covers a trench feature located between the MLA component and the PDA component.

Aspect 11: The photodetector of any of Aspects 1-10, wherein the light blocking material blocks short-wave infrared light.

Aspect 12: The photodetector of any of Aspects 1-11, wherein the light blocking material comprises an adhesive material.

Aspect 13: The photodetector of Aspect 12, wherein the adhesive material comprises a UV curable polymer.

Aspect 14: The photodetector of any of Aspects 1-13, wherein the light blocking material comprises a solid structure.

Aspect 15: The photodetector of any of Aspects 1-14, wherein the MLA comprises a pixel region between the first distal end of the MLA component and the second distal end of the MLA component; and wherein the light blocking material does not cover the pixel region. wherein the light blocking material does not cover the pixel region.

Aspect 16: The photodetector of any of Aspects 1-15, further comprising an interposer component to which the PDA component is attached, wherein the light blocking material is in contact with the interposer component. wherein the light blocking material is in contact with the interposer component.

Aspect 17: A method, comprising: attaching a photodetector to an interposer, the photodetector comprising: an MLA component, and a PDA component; applying a light blocking material to a first distal end of the MLA component; and applying the light blocking material to a second distal end of the MLA component.

Aspect 18: The method of Aspect 17, wherein applying the light blocking material to the first distal end of the MLA component comprises: applying, using an applicator, the light blocking material to a top surface of the MLA component, proximate to a pixel region between the first distal end of the MLA component and the second distal end of the MLA component; and dragging, using the applicator, at least a portion of the light blocking material toward the first distal end of the MLA component, to cause the portion of the light blocking material to cover at least a portion of an edge face of the MLA. applying, using an applicator, the light blocking material to a top surface of the MLA component, proximate to a pixel region between the first distal end of the MLA component and the second distal end of the MLA component; and dragging, using the applicator, at least a portion of the light blocking material toward the first distal end of the MLA component, to cause the portion of the light blocking material to cover at least a portion of an edge face of the MLA.

Aspect 19: The method of any of Aspects 17-18, wherein the light blocking material comprises a UV curable polymer; and wherein the method further comprises: curing the light blocking material. wherein the method further comprises: curing the light blocking material.

Aspect 20: A lidar system, comprising: a photodetector, comprising: an MLA component, a PDA component, and light blocking material applied at a first distal end of the MLA component, and a second distal end of the MLA component; a memory; and at least one processor coupled to the memory and configured to: receive input from the photodetector; and generate a lidar point cloud based at least in part on the input.

Aspect 21: A system configured to perform one or more operations recited in one or more of Aspects 17-19.

Aspect 22: An apparatus comprising means for performing one or more operations recited in one or more of Aspects 17-19.

Aspect 23: A non-transitory computer-readable medium storing a set of instructions, the set of instructions comprising one or more instructions that, when executed by a device, cause the device to perform one or more operations recited in one or more of Aspects 17-19.

Aspect 24: A computer program product comprising instructions or code for executing one or more operations recited in one or more of Aspects 17-19.

Although particular combinations of features are recited in the claims and/or disclosed in the specification, these combinations are not intended to limit the disclosure of various implementations. Features from different implementations and/or aspects disclosed herein can be combined. For example, one or more features from a method implementations may be combined with one or more features of a device, system, or product implementation. Features described herein may be combined in ways not specifically recited in the claims and/or disclosed in the specification. Although each dependent claim listed below may directly depend on only one claim, the disclosure of various implementations includes each dependent claim in combination with every other claim in the claim set. As used herein, a phrase referring to “at least one of” a list of items refers to any combination and permutation of those items, including single members. As an example, “at least one of: a, b, or c” is intended to cover a, b, c, a-b, a-c, b-c, and a-b-c, as well as any combination with multiple of the same item. As used herein, the term “and/or” used to connect items in a list refers to any combination and any permutation of those items, including single members (e.g., an individual item in the list). As an example, “a, b, and/or c” is intended to cover a, b, c, a-b, a-c, b-c, and a-b-c.