Patent Publication Number: US-2023146505-A1

Title: Methods and Apparatuses for Testing Imaging Devices

Description:
BACKGROUND 
     Autonomous or semi-autonomous vehicles include various electronic component devices to facilitate operations of the vehicles, e.g., cameras or other light sensors to gather information about the surrounding environment, processors to process the sensor information to control steering or braking, or both, among others. For vehicle reliability over a wide range of conditions, the sensors are tested for performance in different sensing environments, such as at various temperatures. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         FIG.  1    is an example environment in which a vehicle including one or more components of an autonomous system can be implemented. 
         FIG.  2    is a diagram of one or more systems of a vehicle including an autonomous system. 
         FIG.  3    is a diagram of components of one or more devices and/or one or more systems of  FIGS.  1 - 2  and  4 - 9 B . 
         FIG.  4    is a diagram of example inputs and outputs that may be used by analysis and processing systems. 
         FIG.  5    is a diagram of an example LiDAR system. 
         FIG.  6    is a diagram of an example testing apparatus. 
         FIG.  7    is a diagram of an example temperature controller. 
         FIG.  8    is a diagram of an example testing apparatus including pressure regulation components. 
         FIGS.  9 A- 9 B  are respectively top-view and side-view diagrams of a testing apparatus. 
         FIG.  10    is a flowchart of a process for testing imaging devices. 
     
    
    
     DETAILED DESCRIPTION 
     In the following description numerous specific details are set forth in order to provide a thorough understanding of the present disclosure for the purposes of explanation. It will be apparent, however, that the implementations described by the present disclosure can be practiced without these specific details. In some instances, well-known structures and devices are illustrated in block diagram form in order to avoid unnecessarily obscuring aspects of the present disclosure. 
     Specific arrangements or orderings of schematic elements, such as those representing systems, devices, modules, instruction blocks, data elements, and/or the like are illustrated in the drawings for ease of description. However, it will be understood by those skilled in the art that the specific ordering or arrangement of the schematic elements in the drawings is not meant to imply that a particular order or sequence of processing, or separation of processes, is required unless explicitly described as such. Further, the inclusion of a schematic element in a drawing is not meant to imply that such element is required in all implementations or that the features represented by such element may not be included in or combined with other elements in some implementations unless explicitly described as such. 
     Further, where connecting elements such as solid or dashed lines or arrows are used in the drawings to illustrate a connection, relationship, or association between or among two or more other schematic elements, the absence of any such connecting elements is not meant to imply that no connection, relationship, or association can exist. In other words, some connections, relationships, or associations between elements are not illustrated in the drawings so as not to obscure the disclosure. In addition, for ease of illustration, a single connecting element can be used to represent multiple connections, relationships or associations between elements. For example, where a connecting element represents communication of signals, data, or instructions (e.g., “software instructions”), it should be understood by those skilled in the art that such element can represent one or multiple signal paths (e.g., a bus), as may be needed, to affect the communication. 
     Although the terms first, second, third, and/or the like are used to describe various elements, these elements should not be limited by these terms. The terms first, second, third, and/or the like are used only to distinguish one element from another. For example, a first unit could be termed a second unit and, similarly, a second unit could be termed a first unit without departing from the scope of the described implementations. The first unit and the second unit are both units, but they are not the same unit. 
     The terminology used in the description of the various described implementations herein is included for the purpose of describing particular implementations only and is not intended to be limiting. As used in the description of the various described implementations and the appended claims, the singular forms “a,” “an” and “the” are intended to include the plural forms as well and can be used interchangeably with “one or more” or “at least one,” unless the context clearly indicates otherwise. It will also be understood that the term “and/or” as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items. It will be further understood that the terms “includes,” “including,” “comprises,” and/or “comprising,” when used in this description specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. 
     As used herein, the terms “communication” and “communicate” refer to at least one of the reception, receipt, transmission, transfer, provision, and/or the like of information (or information represented by, for example, data, signals, messages, instructions, commands, and/or the like). For one unit (e.g., a device, a system, a component of a device or system, combinations thereof, and/or the like) to be in communication with another unit means that the one unit is able to directly or indirectly receive information from and/or send (e.g., transmit) information to the other unit. This may refer to a direct or indirect connection that is wired and/or wireless in nature. Additionally, two units may be in communication with each other even though the information transmitted may be modified, processed, relayed, and/or routed between the first and second unit. For example, a first unit may be in communication with a second unit even though the first unit passively receives information and does not actively transmit information to the second unit. As another example, a first unit may be in communication with a second unit if at least one intermediary unit (e.g., a third unit located between the first unit and the second unit) processes information received from the first unit and transmits the processed information to the second unit. In some implementations, a message may refer to a network packet (e.g., a data packet and/or the like) that includes data. 
     As used herein, the term “if” is, optionally, construed to mean “when”, “upon”, “in response to determining,” “in response to detecting,” and/or the like, depending on the context. Similarly, the phrase “if it is determined” or “if [a stated condition or event] is detected” is, optionally, construed to mean “upon determining,” “in response to determining,” “upon detecting [the stated condition or event],” “in response to detecting [the stated condition or event],” and/or the like, depending on the context. Also, as used herein, the terms “has”, “have”, “having”, or the like are intended to be open-ended terms. Further, the phrase “based on” is intended to mean “based at least partially on” unless explicitly stated otherwise. 
     Reference will now be made in detail to implementations, examples of which are illustrated in the accompanying drawings. In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the various described implementations. However, it will be apparent to one of ordinary skill in the art that the various described implementations can be practiced without these specific details. In other instances, well-known methods, procedures, components, circuits, and networks have not been described in detail so as not to unnecessarily obscure aspects of the implementations. 
     General Overview of Vehicle Systems 
     In some aspects and/or implementations, systems and methods described herein include and/or implement environmental testing procedures for testing devices under test, such as cameras, other light sensors, and other devices. An apparatus includes a test chamber with an imaging device and an optical target, with the imaging device configured to detect light associated with the optical target, for example, light originating at and/or reflected by the optical target (e.g., to capture one or more images of the optical target). The imaging device is thermally isolated from the optical target so that temperatures of the imaging device can be varied without causing variations in the operational characteristics of the optical target due to temperature changes. The tested imaging devices can be included in various systems, including vehicles. For example, the tested imaging devices can be included in autonomous vehicles to assist in entity detection. 
     In the following sections, the disclosed systems and methods are described primarily with respect to imaging devices, such as cameras, LiDAR sensors, or other light sensors, being used as one or more devices under test in the test chamber. However, the disclosed systems and methods are applicable to test other types of sensors in the test chamber, including, for example, acoustic devices such as microphones  202   d  described above. 
     By virtue of the implementation of systems, methods, and computer program products described herein, various advantages can be realized. In some implementations, a device under test (e.g., a camera or other light sensor) and an optical target (or respective receptacles to hold these components) are both positioned within a test chamber. This can reduce or avoid complications associated with an intervening test chamber wall (such as condensation and temperature-dependent transmission effects) between the device under test and the optical target. In some implementations, thermal isolation is sustained between a device under test and an optical target (or respective receptacles to receive these components) using an air curtain, allowing a temperature of the device under test to be varied while a temperature of the optical target is approximately constant or separately controlled. This allows the optical target to have uniform characteristics for various temperature-dependent optical tests of the device under test. In doing so, measurements of the characteristics of the device under test are not impacted by temperature-induced variations of the optical target characteristics, which facilitates obtaining accurate and reliable measurements about the device under test over a wide temperature range. This can result in improved sensing performance when imaging devices that are tested/calibrated using these methods and apparatuses are deployed in systems such as autonomous vehicles, compared to methods and apparatuses in which optical targets are not thermally isolated from devices under test when performing temperature-based tests. 
     Referring now to  FIG.  1   , illustrated is an example environment  100  in which vehicles that include autonomous systems, as well as vehicles that do not, are operated. As illustrated, environment  100  includes vehicles  102   a - 102   n,  objects  104   a - 104   n,  routes  106   a - 106   n,  area  108 , vehicle-to-infrastructure (V2I) device  110 , network  112 , remote autonomous vehicle (AV) system  114 , fleet management system  116 , and V2I system  118 . Vehicles  102   a - 102   n,  vehicle-to-infrastructure (V2I) device  110 , network  112 , autonomous vehicle (AV) system  114 , fleet management system  116 , and V2I system  118  interconnect (e.g., establish a connection to communicate and/or the like) via wired connections, wireless connections, or a combination of wired or wireless connections. In some implementations, objects  104   a - 104   n  interconnect with at least one of vehicles  102   a - 102   n,  vehicle-to-infrastructure (V2I) device  110 , network  112 , autonomous vehicle (AV) system  114 , fleet management system  116 , and V2I system  118  via wired connections, wireless connections, or a combination of wired or wireless connections. 
     Vehicles  102   a - 102   n  (referred to individually as vehicle  102  and collectively as vehicles  102 ) include at least one device configured to transport goods and/or people. In some implementations, vehicles  102  are configured to be in communication with V2I device  110 , remote AV system  114 , fleet management system  116 , and/or V2I system  118  via network  112 . In some implementations, vehicles  102  include cars, buses, trucks, trains, and/or the like. In some implementations, vehicles  102  are the same as, or similar to, vehicles  200 , described herein (see  FIG.  2   ). In some implementations, a vehicle  200  of a set of vehicles  200  is associated with an autonomous fleet manager. In some implementations, vehicles  102  travel along respective routes  106   a - 106   n  (referred to individually as route  106  and collectively as routes  106 ), as described herein. In some implementations, one or more vehicles  102  include an autonomous system (e.g., an autonomous system that is the same as or similar to autonomous system  202 ). 
     Objects  104   a - 104   n  (referred to individually as object  104  and collectively as objects  104 ) include, for example, at least one vehicle, at least one pedestrian, at least one cyclist, at least one structure (e.g., a building, a sign, a fire hydrant, etc.), and/or the like. Each object  104  is stationary (e.g., located at a fixed location for a period of time) or mobile (e.g., having a velocity and associated with at least one trajectory). In some implementations, objects  104  are associated with corresponding locations in area  108 . 
     Routes  106   a - 106   n  (referred to individually as route  106  and collectively as routes  106 ) are each associated with (e.g., prescribe) a sequence of actions (also known as a trajectory) connecting states along which an AV can navigate. Each route  106  starts at an initial state (e.g., a state that corresponds to a first spatiotemporal location, velocity, and/or the like) and a final goal state (e.g., a state that corresponds to a second spatiotemporal location that is different from the first spatiotemporal location) or goal region (e.g. a subspace of acceptable states (e.g., terminal states)). In some implementations, the first state includes a location at which an individual or individuals are to be picked-up by the AV and the second state or region includes a location or locations at which the individual or individuals picked-up by the AV are to be dropped-off. In some implementations, routes  106  include a plurality of acceptable state sequences (e.g., a plurality of spatiotemporal location sequences), the plurality of state sequences associated with (e.g., defining) a plurality of trajectories. In an example, routes  106  include only high level actions or imprecise state locations, such as a series of connected roads dictating turning directions at roadway intersections. Additionally, or alternatively, routes  106  may include more precise actions or states such as, for example, specific target lanes or precise locations within the lane areas and targeted speed at those positions. In an example, routes  106  include a plurality of precise state sequences along the at least one high level action sequence with a limited lookahead horizon to reach intermediate goals, where the combination of successive iterations of limited horizon state sequences cumulatively correspond to a plurality of trajectories that collectively form the high level route to terminate at the final goal state or region. 
     Area  108  includes a physical area (e.g., a geographic region) within which vehicles  102  can navigate. In an example, area  108  includes at least one state (e.g., a country, a province, an individual state of a plurality of states included in a country, etc.), at least one portion of a state, at least one city, at least one portion of a city, etc. In some implementations, area  108  includes at least one named thoroughfare (referred to herein as a “road”) such as a highway, an interstate highway, a parkway, a city street, etc. Additionally, or alternatively, in some examples area  108  includes at least one unnamed road such as a driveway, a section of a parking lot, a section of a vacant and/or undeveloped lot, a dirt path, etc. In some implementations, a road includes at least one lane (e.g., a portion of the road that can be traversed by vehicles  102 ). In an example, a road includes at least one lane associated with (e.g., identified based on) at least one lane marking. 
     Vehicle-to-Infrastructure (V2I) device  110  (sometimes referred to as a Vehicle-to-Infrastructure (V2X) device) includes at least one device configured to be in communication with vehicles  102  and/or V2I infrastructure system  118 . In some implementations, V2I device  110  is configured to be in communication with vehicles  102 , remote AV system  114 , fleet management system  116 , and/or V2I system  118  via network  112 . In some implementations, V2I device  110  includes a radio frequency identification (RFID) device, signage, cameras (e.g., two-dimensional (2D) and/or three-dimensional (3D) cameras), lane markers, streetlights, parking meters, etc. In some implementations, V2I device  110  is configured to communicate directly with vehicles  102 . Additionally, or alternatively, in some implementations V2I device  110  is configured to communicate with vehicles  102 , remote AV system  114 , and/or fleet management system  116  via V2I system  118 . In some implementations, V2I device  110  is configured to communicate with V2I system  118  via network  112 . 
     Network  112  includes one or more wired and/or wireless networks. In an example, network  112  includes a cellular network (e.g., a long term evolution (LTE) network, a third generation (3G) network, a fourth generation (4G) network, a fifth generation (5G) network, a code division multiple access (CDMA) network, etc.), a public land mobile network (PLMN), a local area network (LAN), a wide area network (WAN), a metropolitan area network (MAN), a telephone network (e.g., the public switched telephone network (PSTN), a private network, an ad hoc network, an intranet, the Internet, a fiber optic-based network, a cloud computing network, etc., a combination of some or all of these networks, and/or the like. 
     Remote AV system  114  includes at least one device configured to be in communication with vehicles  102 , V2I device  110 , network  112 , remote AV system  114 , fleet management system  116 , and/or V2I system  118  via network  112 . In an example, remote AV system  114  includes a server, a group of servers, and/or other like devices. In some implementations, remote AV system  114  is co-located with the fleet management system  116 . In some implementations, remote AV system  114  is involved in the installation of some or all of the components of a vehicle, including an autonomous system, an autonomous vehicle computer, software implemented by an autonomous vehicle computer, and/or the like. In some implementations, remote AV system  114  maintains (e.g., updates and/or replaces) such components and/or software during the lifetime of the vehicle. 
     Fleet management system  116  includes at least one device configured to be in communication with vehicles  102 , V2I device  110 , remote AV system  114 , and/or V2I infrastructure system  118 . In an example, fleet management system  116  includes a server, a group of servers, and/or other like devices. In some implementations, fleet management system  116  is associated with a ridesharing company (e.g., an organization that controls operation of multiple vehicles (e.g., vehicles that include autonomous systems and/or vehicles that do not include autonomous systems) and/or the like). 
     In some implementations, V2I system  118  includes at least one device configured to be in communication with vehicles  102 , V2I device  110 , remote AV system  114 , and/or fleet management system  116  via network  112 . In some examples, V2I system  118  is configured to be in communication with V2I device  110  via a connection different from network  112 . In some implementations, V2I system  118  includes a server, a group of servers, and/or other like devices. In some implementations, V2I system  118  is associated with a municipality or a private institution (e.g., a private institution that maintains V2I device  110  and/or the like). 
     The number and arrangement of elements illustrated in  FIG.  1    are provided as an example. There can be additional elements, fewer elements, different elements, and/or differently arranged elements, than those illustrated in  FIG.  1   . Additionally, or alternatively, at least one element of environment  100  can perform one or more functions described as being performed by at least one different element of  FIG.  1   . Additionally, or alternatively, at least one set of elements of environment  100  can perform one or more functions described as being performed by at least one different set of elements of environment  100 . 
     Referring now to  FIG.  2   , illustrated is a diagram of one or more systems of a vehicle  200  including an autonomous system  202 . The vehicle  200  includes autonomous system  202 , powertrain control system  204 , steering control system  206 , and brake system  208 . In some implementations, vehicle  200  is the same as or similar to vehicle  102  (see  FIG.  1   ). In some implementations, vehicle  102  has autonomous capability (e.g., implement at least one function, feature, device, and/or the like that enable vehicle  200  to be partially or fully operated without human intervention including, without limitation, fully autonomous vehicles (e.g., vehicles that forego reliance on human intervention), highly autonomous vehicles (e.g., vehicles that forego reliance on human intervention in certain situations), and/or the like). For a detailed description of fully autonomous vehicles and highly autonomous vehicles, reference may be made to SAE International&#39;s standard J3016: Taxonomy and Definitions for Terms Related to On-Road Motor Vehicle Automated Driving Systems, which is incorporated by reference in its entirety. In some implementations, vehicle  200  is associated with an autonomous fleet manager and/or a ridesharing company. 
     Autonomous system  202  includes a sensor suite that includes one or more devices such as cameras  202   a,  LiDAR sensors  202   b,  radar sensors  202   c,  and microphones  202   d.  In some implementations, autonomous system  202  can include more or fewer devices and/or different devices (e.g., ultrasonic sensors, inertial sensors, GPS receivers (discussed below), odometry sensors that generate data associated with an indication of a distance that vehicle  200  has traveled, and/or the like). In some implementations, autonomous system  202  uses the one or more devices included in autonomous system  202  to generate data associated with environment  100 , described herein. The data generated by the one or more devices of autonomous system  202  can be used by one or more systems described herein to observe the environment (e.g., environment  100 ) in which vehicle  200  is located. In some implementations, autonomous system  202  includes communication device  202   e,  autonomous vehicle computer  202   f,  and drive-by-wire (DBW) system  202   h.    
     Cameras  202   a  include at least one device configured to be in communication with communication device  202   e,  autonomous vehicle computer  202   f,  and/or safety controller  202   g  via a bus (e.g., a bus that is the same as or similar to bus  302  of  FIG.  3   ). Cameras  202   a  include at least one imaging device or optical sensor, such as one camera (e.g., a digital camera using a light sensor such as a charge-coupled device (CCD), a thermal camera, an infrared (IR) camera, an event camera, and/or the like) to capture images including physical objects (e.g., cars, buses, curbs, people, and/or the like). In some implementations, camera  202   a  generates camera data as output. In some examples, camera  202   a  generates camera data that includes image data associated with an image. In this example, the image data may specify at least one parameter (e.g., image characteristics such as exposure, brightness, etc., an image timestamp, and/or the like) corresponding to the image. In such an example, the image may be in a format (e.g., RAW, JPEG, PNG, and/or the like). In some implementations, camera  202   a  includes a plurality of independent cameras configured on (e.g., positioned on) a vehicle to capture images for the purpose of stereopsis (stereo vision). In some examples, camera  202   a  includes a plurality of cameras that generate image data and transmit the image data to autonomous vehicle computer  202   f  and/or a fleet management system (e.g., a fleet management system that is the same as or similar to fleet management system  116  of  FIG.  1   ). In such an example, autonomous vehicle computer  202   f  determines depth to one or more objects in a field of view of at least two cameras of the plurality of cameras based on the image data from the at least two cameras. In some implementations, cameras  202   a  is configured to capture images of objects within a distance from cameras  202   a  (e.g., up to 100 meters, up to a kilometer, and/or the like). Accordingly, cameras  202   a  include features such as sensors and lenses that are optimized for perceiving objects that are at one or more distances from cameras  202   a.    
     In an implementation, camera  202   a  includes at least one camera configured to capture one or more images associated with one or more traffic lights, street signs and/or other physical objects that provide visual navigation information. In some implementations, camera  202   a  generates traffic light data associated with one or more images. In some examples, camera  202   a  generates TLD data associated with one or more images that include a format (e.g., RAW, JPEG, PNG, and/or the like). In some implementations, camera  202   a  that generates TLD data differs from other systems described herein incorporating cameras in that camera  202   a  can include one or more cameras with a wide field of view (e.g., a wide-angle lens, a fish-eye lens, a lens having a viewing angle of approximately 120 degrees or more, and/or the like) to generate images about as many physical objects as possible. 
     Laser Detection and Ranging (LiDAR) sensors  202   b  include at least one device configured to be in communication with communication device  202   e,  autonomous vehicle computer  202   f,  and/or safety controller  202   g  via a bus (e.g., a bus that is the same as or similar to bus  302  of  FIG.  3   ). LiDAR sensors  202   b  include a system configured to transmit light from a light emitter (e.g., a laser transmitter). Light emitted by LiDAR sensors  202   b  includes light (e.g., infrared light and/or the like) that is outside of the visible spectrum. In some implementations, during operation, light emitted by LiDAR sensors  202   b  encounters a physical object (e.g., a vehicle) and is reflected back to LiDAR sensors  202   b.  In some implementations, the light emitted by LiDAR sensors  202   b  does not penetrate the physical objects that the light encounters. LiDAR sensors  202   b  also include at least one light detector (e.g., at least one light sensor) which detects the light that was emitted from the light emitter after the light encounters a physical object. In some implementations, at least one data processing system associated with LiDAR sensors  202   b  generates an image (e.g., a point cloud, a combined point cloud, and/or the like) representing the objects included in a field of view of LiDAR sensors  202   b.  In some examples, the at least one data processing system associated with LiDAR sensor  202   b  generates an image that represents the boundaries of a physical object, the surfaces (e.g., the topology of the surfaces) of the physical object, and/or the like. In such an example, the image is used to determine the boundaries of physical objects in the field of view of LiDAR sensors  202   b.    
     Radio Detection and Ranging (radar) sensors  202   c  include at least one device configured to be in communication with communication device  202   e,  autonomous vehicle computer  202   f,  and/or safety controller  202   g  via a bus (e.g., a bus that is the same as or similar to bus  302  of  FIG.  3   ). Radar sensors  202   c  include a system configured to transmit radio waves (either pulsed or continuously). The radio waves transmitted by radar sensors  202   c  include radio waves that are within a predetermined spectrum. In some implementations, during operation, radio waves transmitted by radar sensors  202   c  encounter a physical object and are reflected back to radar sensors  202   c.  In some implementations, the radio waves transmitted by radar sensors  202   c  are not reflected by some objects. In some implementations, at least one data processing system associated with radar sensors  202   c  generates signals representing the objects included in a field of view of radar sensors  202   c.  For example, the at least one data processing system associated with radar sensor  202   c  generates an image that represents the boundaries of a physical object, the surfaces (e.g., the topology of the surfaces) of the physical object, and/or the like. In some examples, the image is used to determine the boundaries of physical objects in the field of view of radar sensors  202   c.    
     Microphones  202   d  includes at least one device configured to be in communication with communication device  202   e,  autonomous vehicle computer  202   f,  and/or safety controller  202   g  via a bus (e.g., a bus that is the same as or similar to bus  302  of  FIG.  3   ). Microphones  202   d  include one or more microphones (e.g., array microphones, external microphones, and/or the like) that capture audio signals and generate data associated with (e.g., representing) the audio signals. In some examples, microphones  202   d  include transducer devices and/or like devices. In some implementations, one or more systems described herein can receive the data generated by microphones  202   d  and determine a position of an object relative to vehicle  200  (e.g., a distance and/or the like) based on the audio signals associated with the data. 
     Communication device  202   e  include at least one device configured to be in communication with cameras  202   a,  LiDAR sensors  202   b,  radar sensors  202   c,  microphones  202   d,  autonomous vehicle computer  202   f,  safety controller  202   g,  and/or DBW system  202   h.  For example, communication device  202   e  may include a device that is the same as or similar to communication interface  314  of  FIG.  3   . In some implementations, communication device  202   e  includes a vehicle-to-vehicle (V2V) communication device (e.g., a device that enables wireless communication of data between vehicles). 
     Autonomous vehicle computer  202   f  includes at least one device configured to be in communication with cameras  202   a,  LiDAR sensors  202   b,  radar sensors  202   c,  microphones  202   d,  communication device  202   e,  safety controller  202   g,  and/or DBW system  202   h.  In some examples, autonomous vehicle computer  202   f  includes a device such as a client device, a mobile device (e.g., a cellular telephone, a tablet, and/or the like), a server (e.g., a computing device including one or more central processing units, graphical processing units, and/or the like), and/or the like. In some implementations, autonomous vehicle computer  202   f  is the same as or similar to autonomous vehicle computer  400 , described herein. Additionally, or alternatively, in some implementations autonomous vehicle computer  202   f  is configured to be in communication with an autonomous vehicle system (e.g., an autonomous vehicle system that is the same as or similar to remote AV system  114  of  FIG.  1   ), a fleet management system (e.g., a fleet management system that is the same as or similar to fleet management system  116  of  FIG.  1   ), a V2I device (e.g., a V2I device that is the same as or similar to V2I device  110  of  FIG.  1   ), and/or a V2I system (e.g., a V2I system that is the same as or similar to V2I system  118  of  FIG.  1   ). 
     Safety controller  202   g  includes at least one device configured to be in communication with cameras  202   a,  LiDAR sensors  202   b,  radar sensors  202   c,  microphones  202   d,  communication device  202   e,  autonomous vehicle computer  202   f,  and/or DBW system  202   h.  In some examples, safety controller  202   g  includes one or more controllers (electrical controllers, electromechanical controllers, and/or the like) that are configured to generate and/or transmit control signals to operate one or more devices of vehicle  200  (e.g., powertrain control system  204 , steering control system  206 , brake system  208 , and/or the like). In some implementations, safety controller  202   g  is configured to generate control signals that take precedence over (e.g., override) control signals generated and/or transmitted by autonomous vehicle computer  202   f.    
     DBW system  202   h  includes at least one device configured to be in communication with communication device  202   e  and/or autonomous vehicle computer  202   f.  In some examples, DBW system  202   h  includes one or more controllers (e.g., electrical controllers, electromechanical controllers, and/or the like) that are configured to generate and/or transmit control signals to operate one or more devices of vehicle  200  (e.g., powertrain control system  204 , steering control system  206 , brake system  208 , and/or the like). Additionally, or alternatively, the one or more controllers of DBW system  202   h  are configured to generate and/or transmit control signals to operate at least one different device (e.g., a turn signal, headlights, door locks, windshield wipers, and/or the like) of vehicle  200 . 
     Powertrain control system  204  includes at least one device configured to be in communication with DBW system  202   h.  In some examples, powertrain control system  204  includes at least one controller, actuator, and/or the like. In some implementations, powertrain control system  204  receives control signals from DBW system  202   h  and powertrain control system  204  causes vehicle  200  to start moving forward, stop moving forward, start moving backward, stop moving backward, accelerate in a direction, decelerate in a direction, perform a left turn, perform a right turn, and/or the like. In an example, powertrain control system  204  causes the energy (e.g., fuel, electricity, and/or the like) provided to a motor of the vehicle to increase, remain the same, or decrease, thereby causing at least one wheel of vehicle  200  to rotate or not rotate. 
     Steering control system  206  includes at least one device configured to rotate one or more wheels of vehicle  200 . In some examples, steering control system  206  includes at least one controller, actuator, and/or the like. In some implementations, steering control system  206  causes the front two wheels and/or the rear two wheels of vehicle  200  to rotate to the left or right to cause vehicle  200  to turn to the left or right. 
     Brake system  208  includes at least one device configured to actuate one or more brakes to cause vehicle  200  to reduce speed and/or remain stationary. In some examples, brake system  208  includes at least one controller and/or actuator that is configured to cause one or more calipers associated with one or more wheels of vehicle  200  to close on a corresponding rotor of vehicle  200 . Additionally, or alternatively, in some examples brake system  208  includes an automatic emergency braking (AEB) system, a regenerative braking system, and/or the like. 
     In some implementations, vehicle  200  includes at least one platform sensor (not explicitly illustrated) that measures or infers properties of a state or a condition of vehicle  200 . In some examples, vehicle  200  includes platform sensors such as a global positioning system (GPS) receiver, an inertial measurement unit (IMU), a wheel speed sensor, a wheel brake pressure sensor, a wheel torque sensor, an engine torque sensor, a steering angle sensor, and/or the like. 
     Referring now to  FIG.  3   , illustrated is a diagram of a device  300  that can correspond to components of one or more devices and/or one or more systems of  FIGS.  1 - 2  and  4 - 9 B . As illustrated, device  300  includes processor  304 , memory  306 , storage component  308 , input interface  310 , output interface  312 , communication interface  314 , and bus  302 . In some implementations, device  300  corresponds to at least one device of vehicles  102  (e.g., at least one device of a system of vehicles  102 ), at least one device of remote AV system  114 , at least one device of fleet management system  116 , at least one device of vehicle-to-infrastructure system  118 , a vehicle-to-infrastructure device  110 , and/or one or more devices of network  112  (e.g., one or more devices of a system of network  112 ). In some implementations, device  300  corresponds to at least one device included in cameras  202   a,  LiDAR sensors  202   b,  radar sensors  202   c,  microphones  202   d,  communication device  202   e,  autonomous vehicle computer  202   f,  safety controller  202   g,  and/or another device of autonomous system  202 . In some implementations, device  300  corresponds to at least one device included in brake system  208 , powertrain control system  204 , drive-by-wire system  202   h,  steering control system  206 , and/or another device of vehicle  200 . In some implementations, device  300  corresponds to at least one device included in control system  618 , temperature controller  616 , temperature control system  712 , control system  824 , temperature controller  812 , and/or device under test  602 ,  702 ,  802 , and/or  904 . 
     Bus  302  includes a component that permits communication among the components of device  300 . In some implementations, processor  304  is implemented in hardware, software, or a combination of hardware and software. In some examples, processor  304  includes a processor (e.g., a central processing unit (CPU), a graphics processing unit (GPU), an accelerated processing unit (APU), and/or the like), a microphone, a digital signal processor (DSP), and/or any processing component (e.g., a field-programmable gate array (FPGA), an application specific integrated circuit (ASIC), and/or the like) that can be programmed to perform at least one function. Memory  306  includes random access memory (RAM), read-only memory (ROM), and/or another type of dynamic and/or static storage device (e.g., flash memory, magnetic memory, optical memory, and/or the like) that stores data and/or instructions for use by processor  304 . 
     Storage component  308  stores data and/or software related to the operation and use of device  300 . In some examples, storage component  308  includes a hard disk (e.g., a magnetic disk, an optical disk, a magneto-optic disk, a solid state disk, and/or the like), a compact disc (CD), a digital versatile disc (DVD), a floppy disk, a cartridge, a magnetic tape, a CD-ROM, RAM, PROM, EPROM, FLASH-EPROM, NV-RAM, and/or another type of computer readable medium, along with a corresponding drive. 
     Input interface  310  includes a component that permits device  300  to receive information, such as via user input (e.g., a touchscreen display, a keyboard, a keypad, a mouse, a button, a switch, a microphone, a camera, and/or the like). Additionally or alternatively, in some implementations input interface  310  includes a sensor that senses information (e.g., a global positioning system (GPS) receiver, an accelerometer, a gyroscope, an actuator, and/or the like). Output interface  312  includes a component that provides output information from device  300  (e.g., a display, a speaker, one or more light-emitting diodes (LEDs), and/or the like). 
     In some implementations, communication interface  314  includes a transceiver-like component (e.g., a transceiver, a separate receiver and transmitter, and/or the like) that permits device  300  to communicate with other devices via a wired connection, a wireless connection, or a combination of wired and wireless connections. In some implementations, communication interface  314  permits device  300  to receive information from another device and/or provide information to another device. In some implementations, communication interface  314  includes an Ethernet interface, an optical interface, a coaxial interface, an infrared interface, a radio frequency (RF) interface, a universal serial bus (USB) interface, a WiFi® interface, a cellular network interface, and/or the like. 
     In some implementations, device  300  performs one or more processes described herein. Device  300  performs these processes based on processor  304  executing software instructions stored by a computer-readable medium, such as memory  305  and/or storage component  308 . A computer-readable medium (e.g., a non-transitory computer readable medium) is defined herein as a non-transitory memory device. A non-transitory memory device includes memory space located inside a single physical storage device or memory space spread across multiple physical storage devices. 
     In some implementations, software instructions are read into memory  306  and/or storage component  308  from another computer-readable medium or from another device via communication interface  314 . When executed, software instructions stored in memory  306  and/or storage component  308  cause processor  304  to perform one or more processes described herein. Additionally or alternatively, in some implementations hardwired circuitry is used in place of or in combination with software instructions to perform one or more processes described herein. Thus, implementations described herein are not limited to any specific combination of hardware circuitry and software unless explicitly stated otherwise. 
     Memory  306  and/or storage component  308  includes data storage or at least one data structure (e.g., a database and/or the like). Device  300  is capable of receiving information from, storing information in, communicating information to, or searching information stored in the data storage or the at least one data structure in memory  306  or storage component  308 . In some examples, the information includes network data, input data, output data, or any combination thereof. 
     In some implementations, device  300  is configured to execute software instructions that are either stored in memory  306  and/or in the memory of another device (e.g., another device that is the same as or similar to device  300 ). As used herein, the term “module” refers to at least one instruction stored in memory  306  and/or in the memory of another device that, when executed by processor  304  and/or by a processor of another device (e.g., another device that is the same as or similar to device  300 ) cause device  300  (e.g., at least one component of device  300 ) to perform one or more processes described herein. In some implementations, a module is implemented in software, firmware, hardware, and/or the like. 
     The number and arrangement of components illustrated in  FIG.  3    are provided as an example. In some implementations, device  300  can include additional components, fewer components, different components, or differently arranged components than those illustrated in  FIG.  3   . Additionally or alternatively, a set of components (e.g., one or more components) of device  300  can perform one or more functions described as being performed by another component or another set of components of device  300 . 
     Referring now to  FIG.  4   , illustrated is an example of inputs  402   a - d  (e.g., sensors  202   a - 202   c  shown in  FIG.  2   ) and outputs  404   a - d  (e.g., sensor data) that are used by analysis and processing systems, such as the autonomous vehicle computer  202   f  ( FIG.  2   ), in some implementations. Analysis and processing systems need not have each of these inputs  402   a - 402   d;  rather, some implementations of analysis and processing systems have zero, one, two, or more of the inputs  402   a - 402   d,  in some implementations in addition to other input types. 
     One input  402   a  is a LiDAR system (e.g., LiDAR sensors  202   b  shown in  FIG.  2   ). As described in reference to  FIG.  2   , LiDAR is a technology that uses light (e.g., bursts of light such as infrared light) to obtain data about physical objects in its line of sight. A LiDAR system produces LiDAR data as output  404   a.  For example, in some implementations LiDAR data includes collections of 3D or 2D points (also known as a point clouds) that are used to construct a representation of the environment  100 . 
     Another input  402   b  is a radar system (e.g., radar sensors  202   c  shown in  FIG.  2   ). As described in reference to  FIG.  2   , radar is a technology that uses radio waves to obtain data about nearby physical objects. Radars can obtain data about objects not within the line of sight of a LiDAR system. A radar system  402   b  produces radar data as output  404   b.  For example, in some implementations radar data includes one or more radio frequency electromagnetic signals that are used to construct a representation of the environment  100 . 
     Another input  402   c  is a camera system (e.g., included in cameras  202   a  shown in  FIG.  2   ). As described in reference to  FIG.  2   , a camera system uses one or more cameras (e.g., digital cameras using a light sensor such as a charge-coupled device [CCD]) to obtain information about nearby physical objects. A camera system produces camera data as output  404   c.  Camera data often takes the form of image data (e.g., data in an image data format such as RAW, JPEG, PNG, etc.). In some examples, the camera system has multiple independent cameras, e.g., for the purpose of stereopsis (stereo vision), which enables the camera system to perceive depth. Although the objects perceived by the camera system are described here as “nearby,” this is relative to an autonomous vehicle or other system in which the camera system is located. In use, the camera system may be configured to “see” objects far, e.g., up to a kilometer or more ahead of the autonomous vehicle or other system in which the camera system is located. Accordingly, the camera system may have features such as sensors and lenses that are optimized for perceiving objects that are far away. 
     Another input  402   d  is a traffic light detection (TLD) system. A TLD system uses one or more cameras to obtain information about traffic lights, street signs, and other physical objects that provide visual navigation information. A TLD system produces TLD data as output  404 d. TLD data often takes the form of image data (e.g., data in an image data format such as RAW, JPEG, PNG, etc.). In some implementations, a TLD system differs from a generic system incorporating a camera in that a TLD system uses one or more cameras (e.g., cameras included in cameras  202   a  shown in  FIG.  2   ) with a wide field of view (e.g., using a wide-angle lens or a fish-eye lens) in order to obtain information about as many physical objects providing visual navigation information as possible, so that the vehicle  200  has access to all relevant navigation information provided by these objects. For example, the viewing angle of a camera in the TLD system may be about  120  degrees or more. 
     In some implementations, outputs  404   a - d  are combined using a sensor fusion technique. Thus, either the individual outputs  404   a - d  are provided to other systems of the vehicle  200  (e.g., provided to an autonomous vehicle computer  202   f  as shown in  FIG.  2   ), and/or the combined output can be provided to the other systems, either in the form of a single combined output or multiple combined outputs of the same type (e.g., using the same combination technique or combining the same outputs or both) or different types (e.g., using different respective combination techniques or combining different respective outputs or both). In some implementations, an early fusion technique is used. An early fusion technique is characterized by combining outputs before one or more data processing steps are applied to the combined output. In some implementations, a late fusion technique is used. A late fusion technique is characterized by combining outputs after one or more data processing steps are applied to the individual outputs. 
     Referring now to  FIG.  5   , illustrated is an example of a LiDAR system  502  (e.g., the input  402   a  shown in  FIG.  4   ). The LiDAR system  502  emits light  504   a - c  from a light emitter  506  (e.g., a laser transmitter). Light emitted by a LiDAR system is typically not in the visible spectrum; for example, infrared light is often used. Some of the light  504   b  emitted encounters a physical object  508  (e.g., a vehicle) and reflects back to the LiDAR system  502 . (Light emitted from a LiDAR system typically does not penetrate physical objects, e.g., physical objects in solid form.) The LiDAR system  502  also has one or more light detectors  510  (e.g., one or more light sensors), which detect the reflected light. In some implementations, one or more data processing systems associated with the LiDAR system generates an image  512  representing the field of view  514  of the LiDAR system. The image  512  includes information that represents the boundaries  516  of a physical object  508 . In this way, the image  512  is used to determine the boundaries  516  of one or more physical objects near an AV. 
     In the interests of user safety and system effectiveness, sensor devices (e.g., one or more of cameras  202   a,    402   c,  or  402   d,  LiDAR sensors  202   b,  or  404   a,  or other suitable imaging devices or other light sensors) should be reliable over a wide range of environmental conditions. For example, accurate sensor outputs (e.g., image data) should be provided over a wide temperature range, such as −40° C. to 85° C. or another temperature range. Accordingly, in some implementations sensor devices are tested for performance in these environmental conditions before being deployed to assist in operations of larger systems such as the vehicle  200  or the LiDAR system  502 . For example, results of the testing can be used to calibrate the sensor devices and/or processing systems, such as the autonomous vehicle computer  202   f,  to improve accuracy of the sensor devices over the temperature range, for example, by applying offsets and/or coefficients to account for changing characteristic(s) of the sensor devices as a function of temperature. As described in greater detail below, in some implementations, the testing is performed in specially-configured test chambers that thermally isolate the sensor devices from optical targets. 
     Testing Apparatuses 
     Referring now to  FIG.  6   , illustrated is an example testing apparatus  600  that includes a test chamber  624 . The test chamber  624  includes a device receptacle  606  and at least one target receptacle  608 . The device receptacle  606  is configured to hold a sensor or imaging device being tested (also referred to as the “device under test”) in a particular position in the test chamber. The target receptacle  608  is configured to hold an optical target in a different particular position in the test chamber. The illustrated example includes a device under test (“DUT”)  602  mounted in the device receptacle  606  and optical targets  604   a,    604   b,    604   c  (referred to collectively as optical targets  604 ) mounted in the target receptacle  608 . The test chamber  624  is sealed to maintain desired temperatures and gas compositions in the test chamber  624  compared to outside the test chamber  624 . 
     The DUT  602  and the optical targets  604  are mounted such that the optical targets  604  are within a field of view  622  of the DUT  602 . A position and/or orientation of the DUT  602  is determined at least in part by a configuration of the device receptacle  606 , and positions and/or orientations of the optical targets  604  are determined at least in part by a configuration of the target receptacle  608 . Accordingly, in some implementations the field of view  622  is determined at least in part by relative positions and respective configurations of the device receptacle  606  and the target receptacle  608 . 
     One purpose of the testing apparatus  600  is to obtain images or other sensed representations of the optical targets  604  as captured by the DUT  602 , while a temperature of the DUT  602  is varied. For example, as described in more detail below, the optical targets  604  can present a slant-edge pattern to the DUT  602 , and images of the slant-edge pattern, which are captured by the DUT  602  as the temperature of the device under test  602  is varied, allow for determination of a modulation transfer function (MTF) of the DUT  602  as a function of temperature. In some cases, the MTF and/or other determined optical parameters guide incorporation of the tested devices into autonomous vehicles and related systems, such as vehicles  102 , vehicle  200 , and LiDAR system  502 . 
     In some implementations, an air curtain controller  610  is configured to generate an air curtain  612  between a location of the device receptacle  606  and/or DUT  602  and locations of target receptacle  608  and/or the optical targets  604 . The air curtain  612  is a controlled stream of gas that flows from the air curtain controller  610  across at least a portion of the test chamber  624 . The dynamics of gas flow around the air curtain  612  thermally isolate the DUT  602  and/or the device receptacle  606  from the optical targets  604  and/or the target receptacle  608 . When the testing apparatus  600  is in use with both the DUT  602  and the optical targets  604  inside the test chamber  624 , and with the air curtain controller  610  generating the air curtain  612 , environmental conditions of the DUT  602  can be varied without causing variations in the operational characteristics of the optical targets  604  due to temperature changes. This can be useful because the optical targets  604 , in some implementations, do not have the same temperature resilience that the DUT  602  does, such that, for example, the optical targets  604  might be damaged or altered if exposed to the same environmental testing conditions as the DUT  602  (e.g., high or low temperatures). For example, a testing pattern presented by the optical targets  604  might have a different visual appearance at high or low temperatures than at moderate temperatures, and/or the optical targets  604  themselves might simply cease to function at high or low temperatures. By use of the air curtain  612 , the DUT  602  is thermally isolated from the optical targets  604  so that the temperature of the DUT  602  can be varied while the temperature of the optical targets is maintained substantially constant and/or is controlled independently of the temperature of the DUT  602 . 
     In some implementations, the gas emitted by the air curtain controller  610  is an inert gas (e.g., nitrogen). In some implementations, the gas emitted by the air curtain controller is low-humidity (e.g., with less than 1% water vapor, less than 0.1% water vapor, or less than 0.01% water vapor). An inert and/or low-humidity gas forming the air curtain  612  can reduce or prevent condensation and other undesirable effects on the DUT  602  and the optical targets  604 . 
     As shown in  FIG.  6   , in some implementations the testing apparatus  600  is realized such that an optical path (e.g., a straight-line optical path  630 ) from the DUT  602  to the optical targets  604  is free of intervening components, such as walls or barriers, at least because both the DUT  602  and the optical targets  604  are inside the test chamber  624 . This allows the DUT  602  to detect light associated with the optical targets  604  (e.g., for the DUT  602  to capture an image of the optical targets  604  using light originating at and/or reflected by the optical targets  604 ) with fewer or no temperature-dependent confounding factors. For example, if the DUT  602  was positioned inside the test chamber  624  while the optical targets  604  were positioned outside the test chamber  624 , walls of the test chamber  624  might modify images of the optical targets  604  as the temperature of the DUT  602  were varied, e.g., because a refractive index of the walls might change as a function of temperature and/or because condensation might form on outer surfaces of the walls as the temperature of the DUT  602  is varied. In some implementations, positioning both the DUT  602  and the optical targets  604  inside the test chamber  624  avoids or reduces these complicating factors, and the simultaneous inclusion of the air curtain controller  610  allows for thermal isolation even with the DUT  602  and the optical targets  604  both inside the test chamber  624 . 
     “Thermally isolated,” as used in this disclosure, refers to two components (e.g., the device receptacle  606  and/or the DUT  602  vis-a-vis the target receptacle  608  and/or the optical targets  604 ) that are substantially thermally decoupled from one another, when the air curtain controller  610  is generating the air curtain  612  and configured to thermally isolate the two components. In some implementations, two components are thermally isolated when a first of the components can have its temperature varied over a given range without operational characteristics of the second component being modified, e.g., without optical or mechanical parameters of the second component being substantially modified. For example, in some implementations, the first component is a DUT or a holder of a DUT, and the first component can have its temperature varied over a range (e.g., −40° C. to 85° C.) without optical or mechanical parameters of the second component (an optical target or a holder of an optical target) being modified to an extent detectable using the DUT. In some implementations, the second component&#39;s temperature is maintained within 5° C. or within 10° C. of an intermediate value due to the air curtain  612  while the first component&#39;s temperature is varied over the range of −40° C. to 85° C. When a first component is thermally isolated from a second component, it can be described that a temperature of the first or the second component can be adjusted substantially independently of a temperature of the other component. 
     In some implementations, the DUT  602  includes at least one light sensor. A device including at least one light sensor can be referred to as an “imaging device.” For example, the DUT  602  can include a camera or a LiDAR sensor, such as cameras  202   a,    402   c,    402   d,  and/or LiDAR sensors  202   b,    402   a.  “Light sensor” includes at least any device that is sensitive to light and that produces and/or that is configurable to produce one or more outputs (e.g., signals such as currents and/or voltages) responsive to the light. In some implementations, the DUT  602  includes multiple individual light sensors (e.g., pixels), outputs of which are indicative of an image sensed by the DUT  602 . In some implementations, the DUT  602  includes a small number of light sensors (e.g., one light sensor), such as in some (but not all) implementations of a LiDAR sensor as the DUT  602 . Types of light sensed by the at least one light sensor can include, in various implementations, visible light, infrared light, ultraviolet light, and/or terahertz-frequency light. In some implementations, the DUT  602  includes a light source (e.g., the light emitter  506 ), such as an incandescent light bulb, a light-emitting diode, and/or a laser, which can emit light in any or all of the wavelength ranges noted for the at least one light sensor. For example, in cases where the DUT  602  includes a LiDAR sensor, a laser of the DUT  602  can illuminate the optical targets  604  for subsequent detection of reflected laser light by the LiDAR sensor. In some implementations, a wavelength detected by a light sensor of the DUT  602  is a wavelength detected by a light source of the DUT  602 . In some implementations, the DUT  602  includes a computer device (e.g., device  300 ) configured to receive (e.g., from another computer system) a command to capture an image and/or detect light, and/or configured to transmit data representative of captured images and/or detected light to the other computer system. 
     The optical targets  604 , in some implementations, include or present patterns that, when analyzed in images captured by the DUT  602 , allow for the determination of optical parameters of the DUT  602  under a given set of environmental conditions. Various implementations of the optical targets  604  are within the scope of this disclosure. For example, optical parameters determinable based on images of the optical targets  604  can include focal length, field curvature, chromatic aberration of at least one type, astigmatism, depth of focus, rotational symmetry, relative illumination and/or sharpness, and the optical targets  604  can be configured differently (e.g., in number, appearance, and/or device type) based on the type of optical parameter(s) to be determined. For example, in some implementations, when determining MTF (which characterizes sharpness), the optical targets  604  include a spatial frequency response (SFR) target, such as a slanted edge pattern, a wedge pattern, and/or a Siemens star pattern. 
     The physical form of the optical targets  604  can also vary depending on the implementation. In some implementations, the optical targets  604  include at least one test pattern printed on paper or another physical medium, at least one test pattern on glass (e.g., as a chrome or other material pattern formed lithographically on the glass), at least one test pattern displayed on a display (e.g., on a computer monitor), and/or at least one test pattern projected from the optical targets  604  to the DUT  602 . The optical targets  604  need not present/display an imaging pattern; for example, in some implementations, the optical targets  604  include a physical object having a known outer topology, e.g., for testing LiDAR sensors that measure boundaries of the physical object by detecting light reflected by the physical object. For projection, in some implementations the optical targets  604  include at least one collimator arranged to project a test pattern into an input pupil of the DUT  602 . The collimators can be fixed-focus with preset infinity or finite object distances, and/or they can be motorized for variable object distances. In some implementations, multiple collimators are employed (e.g., optical targets  604   a,    604   b,    604   c ). For example, each collimator can be used to measure an MTF for a particular field point in a field of view of the DUT, e.g., at multiple spacings from a center of the field of view, such as 0.0F (center of the field of view), 0.5F (50% away from the center of the field of view), and 0.85F (85% away from the center of the field of view). MTF for each field point can have different temperature-dependencies that can be measured separately using separate respective optical targets. Although  FIG.  6    shows three optical targets  604 , a number of the optical targets  604  can, in various implementations, be one, two, or more than three. 
     In some implementations, as shown in  FIG.  6   , the DUT  602  is mounted in/on a device receptacle  606 , and the optical targets  604  are mounted in/on at least one target receptacle  608 . The receptacles  606 ,  608  can include optical mounts (e.g., fixed, kinematic, and/or gimbal mounts), screw-holes such as optical table-standard tapped holes (e.g., M6 and/or ¼-20″ UNC holes), movable mounts able to translate and/or rotate (e.g., optical rails), or any other mechanical device or set of devices able to receive and hold the DUT  602  or optical targets  604  in position for imaging. In implementations that include multiple optical targets  604 , a single target receptacle  608  can receive and hold multiple optical targets  604 , and/or separate target receptacles  608  can hold individual optical targets  604 . Moreover, some implementations do not include either or both of the device receptacle  606  and the at least one target receptacle  608 . For example, the DUT  602  and/or the optical targets  604  can be placed on two respective sides of the air curtain  612  even in the absence of specific receptacle components. 
     To vary temperatures of the DUT  602 , in some implementations the testing apparatus  600  includes a temperature controller  616 . The temperature controller  616  is configured and arranged to adjust a temperature proximate to the device receptacle  606  so as to adjust the temperature of the DUT  602 . In various implementations, the temperature proximate to the device receptacle  606  can be a temperature of the device receptacle  606  itself, a temperature of another component in thermal contact with the DUT  602  when the DUT  602  is positioned in the device receptacle  606 , a temperature of the DUT  602  itself when the DUT  602  is positioned in the device receptacle  606 , and/or an atmospheric temperature (e.g., ambient temperature) in the test chamber  624  that is representative of the temperature of the DUT  602 , such as a temperature of a zone in which the DUT  602  is located. 
     Referring now to  FIG.  7   , illustrated is a diagram of an example temperature controller  700  (e.g., the temperature controller  616 ) that includes at least one temperature adjustment device configured to apply heat and/or remove heat so as to adjust the temperature proximate to the device receptacle. In this example, a heating element  708  includes an inductive coil  706  through which current can be passed to heat a DUT  702  (e.g., DUT  602 ). A cooling element  704  includes a gas jet configured and arranged to spray the DUT  702  with a cold gas (e.g., a gas that is cooler than the DUT  702 ), so as to cool the DUT  702 . In some implementations, the sprayed gas is an inert gas (e.g., nitrogen). In some implementations, the sprayed gas is low-humidity (e.g., with less than 1% water vapor, less than 0.1% water vapor, or less than 0.01% water vapor). An inert and/or low-humidity sprayed gas can reduce or prevent condensation and other undesirable effects on the DUT  702 . 
     Implementations of the temperature controller  700  can instead or additionally include other types of temperature adjustment devices, such as resistive heaters, gas jets configured to spray the DUT  702  with hot gas (e.g., a gas that is warmer than the DUT  702 ), and/or Peltier devices in thermal contact with the DUT  702  and/or a device receptacle (not shown). A Peltier device can, in some implementations, both heat and cool the DUT  702  depending on a direction and magnitude of current/voltage applied to the Peltier device. In some implementations, the temperature controller  700  is configured to adjust the temperature proximate to the device receptacle within a range of −40° C. to 85° C., or another range. 
     A temperature control system  712  is in communication with (e.g., electronically coupled) at least one temperature sensor  710  arranged to measure the temperature proximate to the device receptacle, and to the at least one temperature adjustment device (in this example, the heating element  708  and the cooling element  704 ). The at least one temperature sensor  710  can include a thermocouple, a resistive sensor, a diode-based sensor, an optical sensor, and/or another type of temperature sensor. 
     The temperature control system  712  includes at least one computer device, e.g., device  300 . In some implementations, the temperature control system  712  receives a stream of data indicative of the measured temperature proximate to the device receptacle from the temperature sensor  710  and adjusts operations of the heating element  708  and/or the cooling element  704  to cause the temperature proximate to the device receptacle to reach a target temperature. For example, if the measured temperature is different from the target temperature, the temperature control system  712  can increase or decrease a current flowing through the inductive coil  706 , and/or increase or decrease a rate of gas sprayed by the gas jet of the cooling element  704 , to cause a current temperature proximate to the device receptacle to match or become closer to (e.g., within a defined temperature difference from) the target temperature. In some implementations, the temperature control system  712  includes a PID module  714  configured to apply a proportional-integral-derivative-type algorithm to perform temperature control. In some implementations, at least one other algorithm is instead or additionally employed. 
     In some implementations, the temperature control system  712  includes at least some components configured to measure and/or adjust one or more temperatures besides the temperature proximate to the device receptacle. For example, in some implementations the temperature control system  712  includes a temperature sensor arranged to measure a temperature proximate to a target receptacle (e.g., a temperature of the target receptacle itself, a temperature of another component in thermal contact with an optical target when the optical target is positioned in the target receptacle, a temperature of the optical target itself when the optical target is positioned in the target receptacle, and/or an atmospheric temperature in the test chamber (e.g., ambient temperature) that is representative of the temperature of the optical target, such as a temperature of a zone in which the optical target is located). In some implementations, the temperature control system  712  includes at least one heating and/or cooling element (e.g., as described for heating element  708  and cooling element  704 ) arranged and configured to adjust the temperature proximate to the target receptacle, e.g., based on a target temperature proximate to the target receptacle set by the temperature control system  712 . These capabilities can supplement the thermal isolation provided by the air curtain, such as by setting the target temperature proximate to the target receptacle to room temperature and using at least one heating and/or cooling element to adjust the temperature proximate to the target receptacle to room temperature. 
     Referring again to  FIG.  6   , in some implementations a control system  618  is in communication with (e.g., electrically coupled) at least one other component of the testing apparatus  600  and is configured to control operations of the testing apparatus  600 . For example, in some implementations the control system  618  includes the temperature controller  616  or is in communication with the temperature controller  616 . The control system  618  is configured to perform temperature regulation using the temperature controller  616 , e.g., by providing a target temperature and commands to the temperature controller  616 . The control system  618  includes at least one computer device, e.g., device  300 . In various implementations, the control system  618  can be local to the test chamber  624  and outside the test chamber  624 , within the test chamber  624 , and/or remote from the test chamber  624 , e.g., at least partially as a cloud-based or server-based control system. 
     In some implementations, the control system  618  is configured to cause test operations to be performed. For example, in some implementations the control system  618  is in communication with (e.g., electrically coupled to) the DUT  602 , and the control system  618  is configured to send at least one signal to the DUT  602  to cause the DUT  602  to capture an image of the optical targets  604  and/or otherwise detect light originating at and/or reflected by the optical targets  604 . For example, the control system  618  can be configured to send the at least one signal in response to a user input received at the control system  618 , a signal received at the control system  618  from a remote source, and/or in response to determining, based on at least one temperature data stream from the temperature controller  616 , that the temperature proximate to the device receptacle  606  is at or within a defined difference from a target temperature. 
     In some implementations, the control system  618  is configured to cause a multi-temperature testing routine. The control system  618  sets a target temperature in a sequence of multiple target temperatures, and the temperature controller  616  controls the temperature proximate to the device receptacle  606  to be at or within a predetermined difference from the target temperature. The control system  618  causes the air curtain controller  610  to create an air curtain  612 , such that the DUT  602  is thermally isolated from the optical targets  604 . In response to receiving temperature data from the temperature controller indicating that the temperature proximate to the device receptacle  606  is at or within the defined difference from the target temperature, the control system  618  causes the DUT  602  to capture at least one corresponding image of the optical targets  604 . In some implementations, the control system  618  is configured to receive data representative of images captured by the DUT  602 . This process can be repeated for subsequent target temperatures in the sequence of multiple target temperatures. 
     In some implementations, the testing apparatus  600  includes at least one component configured to control an atmosphere and pressure within the test chamber  624 . In this example, the testing apparatus  600  includes two pressure sensors  614   a,    614   b,  an outlet valve  620 , and a gas inlet  628 , the operations of which are described in further detail in reference to  FIG.  8   . 
     Referring now to  FIG.  8   , illustrated is a diagram of an example testing apparatus  800  (e.g., the testing apparatus  600 , with, in some implementations, at least one component elided for clarity) that includes pressure regulation components. The testing apparatus  800  includes a control system  824  (e.g., control system  618 , including a computer device such as device  300 ), a DUT  802  (e.g., DUT  602 ), at least one optical target  804  (e.g., optical targets  604 ), an air curtain controller  822  configured to generate an air curtain  806  (e.g., air curtain  612 ), a temperature controller  812  (e.g., temperature controller  616 ), a test chamber  828  (e.g., test chamber  624 ), two pressure sensors  818   a,    818   b  (e.g., pressure sensors  614   a,    614   b ), an outlet valve  814  (e.g., outlet valve  620 ) in fluidic communication with a pump  816 , and a gas inlet  826  (e.g., gas inlet  628 ). 
     Although the DUT  802  and the optical target  804  are both within the test chamber  828 , the air curtain  806 , in some implementations, provides a strong enough gaseous barrier to sustain a steady-state pressure difference between a first zone  808  on a first side of the air curtain  806  (including the optical target  804 ) and a second zone  810  on a second side of the air curtain  806  (including the DUT  802 ). A first pressure sensor  818   a  is configured and arranged to sense a first pressure of the first zone  808 , while a second pressure sensor  818   b  is configured and arranged to sense a second pressure of the second zone  810 . The first zone  808  and the second zone  810  are separated by the air curtain  806 . Although this example includes the two pressure sensors  818   a,    818   b,  in some implementations no pressure sensors, one pressure sensor, or more than two pressure sensors are included. 
     The control system  824  is configured to perform operations and control other components of the testing apparatus  800  based on pressures sensed by the pressure sensors  818   a,    818   b  and/or based on temperatures sensed by a temperature sensor (e.g., temperature sensor  710 ) of the temperature controller  812 . In general, these operations fulfill at least one of two purposes. First, thermal isolation is maintained between the first zone  808  and the second zone  810  (e.g., between the DUT  802  and the optical target  804 ), which depends on a configuration of the air curtain controller  822 , e.g., that the air curtain  806  includes a sufficiently high flow of gas. Second, one or more pressures within the test chamber  828  are maintained at or within certain levels, in absolute terms and/or relatively, e.g., so as not to exceed a limit beyond which operations of the air curtain  806  will be disrupted. In some implementations, these operations and controls are performed by a pressure control system (not shown), which can be a module of the control system  824  and/or a distinct system in communication with the control system  824 . 
     Controlling at least one of the outlet valve  814 , the gas inlet  826 , or the pump  816  allows the control system  824  to set pressures within the test chamber  828 , e.g., either or both of pressures of the first zone  808  and the second zone  810 . The gas inlet  826  provides gas into the test chamber  828  separately from the air curtain controller  822  and temperature-regulating air jets (if present). As described for the air curtain controller and air jets, in some implementations the gas provided by the gas inlet  826  is inert and/or low-humidity. In some implementations, the gas inlet  826  is controllable in a binary manner, e.g., to either provide or not provide gas at any given time. In some implementations, the gas inlet  826  is controllable in an adjustable manner to set one of multiple non-zero flow rates of gas into the test chamber  828 . Note that although  FIG.  8    shows one gas inlet  826  that provides gas into the second zone  810 , in some implementations a gas inlet additionally or instead provides gas into the first zone  808 . Some implementations include multiple gas inlets and some implementations do not include a gas inlet, e.g., gas is provided into the test chamber  828  primarily in the form of the air curtain  806 . 
     The outlet valve  814  (e.g., a one-way valve) provides a path through which gas in the test chamber  828  flows out of the test chamber  828 . Because gas will generally be provided constantly into the testing apparatus  800  by the air curtain controller  822  when the testing apparatus  800  is in operation, in some implementations maintenance of steady-state pressure(s) in the test chamber necessitates corresponding ongoing removal of gas, such as through the outlet valve  814 . In some implementations, the outlet valve  814  is controllable in a binary manner, e.g., to either release or not release gas at any given time. In some implementations, the outlet valve  814  is controllable in an adjustable manner to set one of multiple non-zero flow rates of gas out of the test chamber  828 . In some implementations, the outlet valve  814  is in fluidic communication with (e.g., through pipes  830 ) a pump  816 . The pump  816 , when present, can be controllable in either or both of a binary manner or an adjustable manner (e.g., an adjustable pumping strength and/or speed). Control of either or both of the outlet valve  814  or the pump  816  allows the control system  824  to control a rate of gas removal from the test chamber  828 . Note that although  FIG.  8    shows one outlet valve  814  in the first zone  808 , in some implementations an outlet valve is instead or additionally in the second zone  810 , and some implementations include multiple outlet valves. 
     In some implementations, the control system  824  is in communication with the temperature controller  812 , for example, configured to receive a stream of temperature data indicative of at least one temperature from at least one temperature sensor (e.g., temperature sensor  710 ) of the temperature controller  812 . In some implementations, the at least one temperature includes a temperature proximate to a device receptacle and/or a temperature proximate to a target receptacle. These and other temperatures can be used as bases for pressure and atmospheric control operations. 
     In some implementations, pressure and atmospheric control operations of the control system  824  include at least one of the following example operations. In some implementations, the control system  824  is configured to adjust at least one of a pressure of the first zone  808  or a pressure of the second zone  810  such that a difference between the pressure of the first zone  808  and the pressure of the second zone  810  is within a defined limit. For example, the defined limit can be a limit beyond which gas flow of the air curtain  806  would be disrupted, such as 10 Pa, 20 Pa, 30 Pa, 50 Pa, or another defined limit. In some implementations, the defined limit is at least partially based on a current configuration of the air curtain controller  822 , e.g., a current rate of gas provided to form the air curtain  806  and/or a current velocity of the gas forming the air curtain  806 . The current configuration of the air curtain controller  822  can be obtained by the control system  824  from the air curtain controller. 
     The pressure difference can be adjusted by at least one of adjusting a rate of gas flow through the gas inlet  826 , adjusting a rate of gas flow through the outlet valve  814 , and/or adjusting a rate of gas removed by the pump  816 . For example, if the pressure difference is determined to be too high (e.g., because an air jet of the temperature controller is elevating the pressure of the second zone  810  compared to the pressure of the first zone  808 ), the control system  824  can reduce a rate of gas input by the gas inlet  826  and/or reduce a rate of gas leaving through the outlet valve  814 . 
     In some implementations, the control system  824  is configured to adjust at least one of a pressure of the first zone  808  or a pressure of the second zone  810  such that the pressure of the first zone  808  and/or the pressure of the second zone  810  is within a defined limit with respect to an ambient pressure outside the test chamber  828 . In various implementations, the defined limit can be  1500  Pa,  1000 , Pa,  500  Pa, or another value, and the defined limit can include either or both of an upper limit (for a pressurized test chamber  828 ) or a lower limit (for a test chamber  828  at a partial vacuum with respect to ambient). The pressure difference can be adjusted by at least one of adjusting a rate of gas flow through the gas inlet  826 , adjusting a rate of gas flow through the outlet valve  814 , and/or adjusting a rate of gas removed by the pump  816 . 
     In some implementations, the control system  824  is configured to control a configuration of the air curtain controller  822  based on temperature data. The temperature data can include at least one of (i) a target temperature for the temperature controller  812  to set, or (ii) at least one temperature measured by the temperature controller  812 . In some implementations, the target temperature corresponds to a configuration of the air curtain controller  822  that will provide thermal isolation when the temperature proximate to the device receptacle is at the target temperature, e.g., a rate of gas provided to form the air curtain  806  and/or a velocity of the gas forming the air curtain  806 . In some implementations, the air curtain controller  822  is configured to access a stored relationship between target temperatures and configurations of the air curtain controller  822 , and to configure the air curtain controller  822  to have a configuration matching a current target temperature. For example, larger deviations of the target temperature from room temperature can correspond to more gas flow and/or faster gas flow to form the air curtain  806 . In some implementations, the same or similar control operations are instead or additionally performed based on at least one temperature measured by the temperature controller  812 , e.g., a temperature proximate to a device receptacle and/or a temperature proximate to a target receptacle. For example, the at least one temperature can correspond to a configuration of the air curtain controller  822  that will provide thermal isolation given the at least one temperature. In some implementations, the air curtain controller  822  is configured to access a stored relationship between the at least one temperature measured by the temperature controller  812  and configurations of the air curtain controller  822 , and configure the air curtain controller  822  to have a configuration matching the at least one temperature. 
     Referring now to  FIGS.  9 A- 9 B , illustrated are top-view and side-view diagrams, respectively, of a testing apparatus  900  in two respective configurations, the two configurations corresponding to two angles of emission of an air curtain. The testing apparatus  900  includes a DUT  904  (e.g., DUT  602 ) mounted on a device receptacle  930  (e.g., device receptacle  606 ); an optical target  906  (e.g., optical target  604 ) mounted on a target receptacle  932  (e.g., target receptacle  608 ); a test chamber  902  (e.g., test chamber  624 ) enclosing the device receptacle  930  and target receptacle  932 , among other components; and an air curtain controller  908  configured to generate air curtain  914  in  FIG.  9 A  and air curtain  926  in  FIG.  9 B . 
     In some implementations, the air curtain controller  908 , and/or other air curtain controllers described in this disclosure, includes at least one component  918  that moves and/or treats gas to form the air curtains  914 ,  926 . In some implementations, the at least one component  918  includes a fan, pump, and/or other type of gas mover that emits gas into the test chamber  902  to form the air curtains  914 ,  926 . In some implementations, the at least one component  918  includes a plenum that distributes the emitted gas evenly across a width of the air curtains  914 ,  926 . In some implementations, the at least one component  918  includes a dehumidifier to reduce the humidity of the emitted gas. In some implementations, the at least one component  918  includes a computer device (e.g., device  300 ) configured to control generation of the air curtains  914 ,  926 , e.g., in response to commands sent by a control unit. In some implementations, the computer device of the air curtain controller is wholly or partially included (e.g., as a module) in a broader control system of the testing apparatus  900 , such as control system  618  or control system  824 . In some implementations, the at least one component  918  includes at least one temperature adjustment device to control a temperature of the emitted gas, e.g., to maintain the temperature of the emitted gas within a defined range, such as within a determined temperature difference from room temperature. In some implementations, the at least one component  918  includes a filter configured to remove dirt, dust, and other possible contaminants from the emitted gas. These components  918 , and other components, can be present in any combination, in various implementations. In some implementations, the emitted gas is provided into the air curtain controller  908  from an external source (e.g., a gas tank). In some implementations, the emitted gas is at least partially drawn from within the test chamber  902  itself, e.g., as recirculated air. 
     The physical arrangement of the air curtain controller  908 , and accordingly the direction of flow of the air curtains  914  or  926 , can vary depending on the implementation. In some implementations, for effective thermal isolation, the stream of gas forming the air curtain is directed in a substantially transverse direction between the device receptacle  930  and/or the DUT  904  and the target receptacle  932  and/or the optical target  906 . “Substantially transverse,” as used in this disclosure, refers to angles, in various implementations, within 45°, within 30°, within 20°, or within 10° of a line perpendicularly bisecting a line segment between the two components. In the example of  FIG.  9 A , the air curtain controller  908  is positioned at a sidewall  938  of the test chamber  902 , and the air curtain  914  is a stream of gas directed in the direction  912  which is at a substantially transverse lateral angle  916  with respect to a lateral line  910  perpendicularly bisecting a vertical line segment (not shown) between the device receptacle  930  and/or the DUT  904  and the target receptacle  932  and/or the optical target  906 . In the example of  FIG.  9 B , the air curtain controller  908  is positioned at a ceiling  936  of the test chamber  902 , and the air curtain  926  is a stream of gas directed in the direction  924  which is at a substantially transverse vertical angle  928  with respect to a vertical line  922  bisecting a lateral line segment (not shown) between the device receptacle  930  and/or the DUT  904  and the target receptacle  932  and/or the optical target  906  “Lateral” here refers to a direction parallel to a ground surface (e.g., ground surface  940  in  FIG.  9 B ), and “vertical” here refers to a direction parallel to a sidewall surface perpendicular to the ground surface (e.g., sidewall surface  942  in  FIG.  9 A ). In some implementations, the angle is tilted towards the device receptacle  930  and/or the DUT  904  and away from the target receptacle  932  and/or the optical target  906 . 
     Example Processes For Test Image Capture 
     Referring now to  FIG.  10   , illustrated is a flowchart of a process  1000  for testing imaging devices, and specifically an example process  1000  for detecting light associated with an optical target using a DUT. In some implementations, the process  1000  is performed at least in part by the control system  618  that is coupled to various components of the testing apparatus  600 . However, as described above, in some implementations the testing apparatus  600  is the same as, includes, or is in communication with (e.g., controllable communication with) other systems including, in some implementations, the temperature control systems  712 ,  812  and/or control system  824 . Accordingly, in describing the process  1000 , references are made to components shown in  FIGS.  6 - 9 B  where applicable. References to specific example components in describing process  1000  does not mean that other components could not perform the same or similar functions, in keeping with the above disclosure. Moreover, in some implementations at least some of the process  1000  (e.g., arrangement of components) is performed by a user and/or a manipulating tool. 
     The process  1000  starts with arranging of an imaging device in a test chamber and an optical target in the test chamber, such that the optical target is within a field of view of the imaging device ( 1002 ). For example, the imaging device (the DUT  602 ) is positioned in the device receptacle  606 , and the DUT  602  is positioned in the target receptacle  608 , e.g., by a user or by at least one movable component (e.g., a gimbal) of the device receptacle  606  and/or target receptacle  608 . For example, the field of view (e.g., field of view  622 ) can be a field of view that can be captured by the imaging device as an image and/or a field of view within which the imaging device can detect light. 
     The process  1000  continues with the generation of an air curtain in a region of the test chamber between a location of the optical target a and a location of the imaging device, the air curtain configured to thermally isolate the imaging device from the optical target ( 1004 ). For example, the air curtain is generated by the air curtain controller  822  or  908 . For example, a configuration of the air curtain (e.g., a flow rate or flow speed) is set by a control system that includes at least part of and/or is in communication with the air curtain controller, such as control system  618  or control system  824 . For example, the control system transmits an instruction to the air curtain controller to cause the air curtain controller to generate the air curtain. 
     A temperature of the imaging device is adjusted ( 1006 ). For example, temperature control system  712  receives a target temperature from control system  618  and uses one or both of cooling element  704  or heating element  708  to cause a temperature of the imaging device (as sensed using temperature sensor  710 ) to approach the target temperature. 
     Light associated with the optical target is detected using the imaging device ( 1008 ). For example, control system  618  receives, from the temperature controller  616 , an indication that the temperature of the imaging device is at or within a defined distance from the target temperature, and, in response, the control system  618  provides an instruction to the imaging device to cause the imaging device to capture an image of the optical target. 
     In some cases, the air curtain controller  822  generates the air curtain by directing a stream of gas in a substantially transverse direction between the imaging device and the optical target. For example, the substantially transverse direction has an a laterally- and/or vertically-defined angle as described in reference to  FIGS.  9 A- 9 B . 
     In some cases, cooling element  704  sprays the imaging device with gas to cool the imaging device. In some cases, heating element  708  heats the imaging device with an inductive coil in thermal contact with the imaging device. 
     In some cases, a collimator within the test chamber projects the optical target to the imaging device. For example, the collimator can project a slanted edge pattern, a wedge pattern, and/or a Siemens star pattern. 
     In some cases, at least one of (i) a first pressure of a first chamber zone that includes the location of the imaging device, or (ii) a second pressure of a second chamber zone that includes the location of the optical target, is regulated such that a difference between the first pressure and the second pressure is within a defined limit. For example, the control system  824  receives respective streams of data from either or both of pressure sensors  818   a,    818   b,  and reconfigures at least one of the gas inlet  826 , the outlet valve  814 , or the pump  816  to cause the difference between pressures to be within the defined limit. 
     In some cases, the device under test includes a light sensor. For example, the device under test includes a camera such as cameras  202   a,    402   c,  or  402   d,  or a LiDAR sensor such as LiDAR sensor  202   b  or  402   a.  For example, the camera captures an image of the optical target by detecting light originating at and/or reflected by the optical target. For example, light is emitted towards the optical target, and the LiDAR sensor detects the light reflected by the optical target. 
     In the foregoing description, aspects and implementations of the present disclosure have been described with reference to numerous specific details that can vary from implementation to implementation. Accordingly, the description and drawings are to be regarded in an illustrative rather than a restrictive sense. The sole and exclusive indicator of the scope of the invention, and what is intended by the applicants to be the scope of the invention, is the literal and equivalent scope of the set of claims that issue from this application, in the specific form in which such claims issue, including any subsequent correction. Any definitions expressly set forth herein for terms included in such claims shall govern the meaning of such terms as used in the claims. In addition, when we use the term “further comprising,” in the foregoing description or following claims, what follows this phrase can be an additional step or entity, or a sub-step/sub-entity of a previously-recited step or entity.