Window obscuration of an imager near the focal plane

Abstract

The present disclosure relates to optical systems and methods of operation thereof. An example optical system includes an optical component and one or more light sources configured to emit a light signal. The light signal interacts with the optical component to provide an interacted light signal. The optical system also includes a detector configured to detect at least a portion of the interacted light signal as a detected light signal. The optical system additionally includes a controller configured to perform operations including causing the one or more light sources to emit the light signal and receiving the detected light signal from the detector. The operations further include determining, based on the detected light signal, one or more defects associated with the optical component.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of U.S. Patent Application No. 16 / 532,688, filed August 6, 2019, the contents of which are incorporated herein by reference. Technical Field

[0003] Example embodiments relate to methods and systems for detecting occlusions on or defects within optical components of a LIDAR device or another type of optical system. Background Art

[0004] Light detection and ranging (LIDAR) devices can estimate the distance to objects in a given environment by emitting light pulses into the environment and determining the corresponding time of flight of each light pulse. The time of flight of each light pulse can be used to estimate the distance to reflective objects in the environment and / or create a three-dimensional point cloud indicating the reflective objects in the environment. However, optical aberrations and / or defects along the optical path of the light pulses can lead to erroneous point clouds and / or distance information. Summary of the Invention

[0005] Example embodiments relate to methods and systems for detecting occlusions (e.g., the presence of debris) on or defects (e.g., cracks, impurities, scratches, voids, bubbles, etc.) within optical components of a LIDAR device or another type of optical system (e.g., a camera).

[0006] In a first aspect, an optical system is provided. The optical system includes an optical component and one or more light sources configured to emit light signals. The light signals interact with the optical component to provide interaction light signals. The optical system also includes a detector configured to detect at least a portion of the interaction light signals as detected light signals. The optical system additionally includes a controller having at least one processor and at least one memory. The at least one processor executes instructions stored in the at least one memory to perform operations. The operations include causing the one or more light sources to emit light signals and receiving detected light signals from the detector. The operations additionally include determining, based on the detected light signals, that one or more defects are associated with the optical component.

[0007] In a second aspect, a method is provided. The method includes causing one or more light sources to emit a light signal. The light signal interacts with an optical component of an optical system to provide an interaction light signal. The method also includes detecting at least a portion of the interaction light signal as a detected light signal using a detector disposed within a housing of the optical system. The method additionally includes determining, based on the detected light signal, that one or more defects are associated with the optical component.

[0008] Other aspects, embodiments, and implementations will become apparent to those of ordinary skill in the art upon reading the following detailed description in conjunction with the drawings. BRIEF DESCRIPTION OF DRAWINGS

[0009] Figure 1 An optical system interacting with an environment is shown in accordance with example embodiments.

[0010] Figure 2A An optical system is shown in accordance with example embodiments.

[0011] Figure 2B A portion of an optical system is shown in accordance with example embodiments. Figure 2A

[0012] Figure 2C A portion of an optical system is shown in accordance with example embodiments. Figure 2A

[0013] Figure 2D A portion of an optical system is shown in accordance with example embodiments. Figure 2A

[0014] Figure 2E A portion of an optical system is shown in accordance with example embodiments. Figure 2A

[0015] Figure 3A An optical system is shown in accordance with example embodiments.

[0016] Figure 3B A portion of an optical system is shown in accordance with example embodiments. Figure 3A

[0017] A portion of an optical system is shown in accordance with example embodiments. Figure 3C Figure 3A A portion of an optical system is shown in accordance with example embodiments.

[0018] Figure 4 An image of an optical system is shown in accordance with example embodiments.

[0019] Figure 5A A vehicle is shown in accordance with example embodiments.

[0020] Figure 5B A vehicle is shown in accordance with example embodiments.

[0021] Figure 5C A vehicle is shown in accordance with example embodiments.

[0022] Figure 5D A vehicle is shown in accordance with example embodiments.

[0023] Figure 5E ​​​​​A vehicle is shown in accordance with example embodiments.

[0024] Figure 6 A method is shown in accordance with example embodiments. DETAILED DESCRIPTION

[0025] Example methods, devices, and systems are described herein. It should be understood that the words “example” and “exemplary” are used herein to mean “serving as an example, instance, or illustration.” Any implementation or feature described herein as being “example” or “exemplary” is not necessarily to be construed as preferred or advantageous over other implementations or features. Other implementations can be used, and other changes can be made, without departing from the scope of the subject matter presented herein.

[0026] Accordingly, the example embodiments described herein are not meant to be limiting. The aspects of the disclosure generally described herein and illustrated in the figures can be arranged, substituted, combined, separated, and designed in various different configurations, all of which are contemplated herein.

[0027] Furthermore, the features illustrated in each figure can be used with one another in various combinations, as is understood by those skilled in the art. Thus, the figures generally should be considered in the context of the entire disclosure, and not as limitations on the scope of the disclosure. For example, while a range of values is provided, it is understood that any value within that range can be used, and that not all possible combinations are illustrated.

[0028] I. OVERVIEW

[0029] Cameras and image sensors are devices used to capture images of a scene. Some cameras (e.g., film cameras) capture images chemically on film. Other cameras (e.g., digital cameras) capture image data electrically (e.g., using a charge-coupled device (CCD) or complementary metal-oxide-semiconductor (CMOS) sensor). Images captured by a camera can be analyzed to determine their content. For example, a processor can execute a machine learning algorithm to identify objects in a scene based on a library of previously classified objects including the shape, color, size, etc. of the objects (e.g., such machine learning algorithms can be applied to computer vision in robots or other applications).

[0030] Cameras can have a variety of features that can distinguish one camera from another. For example, cameras and / or images captured by a camera can be identified by values such as aperture size, f-number, exposure time, shutter speed, depth of field, focal length, International Organization for Standardization (ISO) sensitivity (or gain), pixel size, sensor resolution, exposure distance, etc. These features can be based on the lens, image sensor, and / or other aspects of the camera. Furthermore, these features can also be adjustable within a single camera (e.g., the aperture of a lens on a camera can be adjusted between photos).

[0031] Light detection and ranging (LIDAR) devices can estimate or be used to estimate distances to objects in a given environment. For example, a transmitter subsystem of a LIDAR system can emit near-infrared light pulses that can interact with objects in the LIDAR system’s environment. At least a portion of the light pulses can be redirected back toward the LIDAR (e.g., due to reflection or scattering) and detected by a receiver subsystem. Conventional receiver subsystems can include multiple detectors and corresponding controllers configured to determine times of arrival of individual light pulses with high temporal resolution (e.g., ~400 ps). Distances between the LIDAR system and a given object can be determined based on times of flight of corresponding light pulses that interacted with the given object. Moreover, data from a LIDAR device can be used to generate a point cloud (e.g., a three-dimensional point cloud) based on pulses detected by the light detectors.

[0032] In some cases, defects in optical components within a camera or LIDAR device can cause aberrations within corresponding captured images or generated point clouds. For example, scratches, cracks, smudges, distortions, debris, voids, bubbles, impurities, deterioration, discoloration, imperfect transparency, warping, or condensation, among others, can cause light from a scene to be directed to unintended / inaccurate areas of an image sensor / light detector, can prevent light from a scene from reaching an image sensor / light detector, or can otherwise modify light from a scene before it reaches an image sensor / light detector (e.g., modify polarization or wavelength). Such aberrations can cause inaccurate object recognition, distance determinations, or other errors. In turn, such errors can impact operation of an autonomous vehicle that receives data from the camera or LIDAR device.

[0033] Example embodiments are directed to methods and systems for detecting occlusions (e.g., presence of debris) on optical components of a LIDAR device or camera or defects (e.g., cracks, impurities, scratches, voids, bubbles, etc.) within optical components. For example, example methods and systems can be directed to detecting contamination (e.g., dirt, water, ice, etc.) on an external window of a LIDAR device.

[0034] The detection techniques disclosed herein can include emitting a light signal from a light source to illuminate an optical component on which a diagnostic test is being performed. In some embodiments, the light source can illuminate one or more surfaces of the optical component. As an example, the illuminated surfaces of the optical component can be imaged by one or more cameras located at or near the focal plane of the optical system. In some embodiments, the cameras can be incorporated into the primary image sensor of the optical system. In other embodiments, the cameras can be mounted in other locations within the housing of the optical system to image the optical component to check it for obscuration features (e.g., dirt, water, ice, etc.) or other types of aberration-causing elements (e.g., cracks, scratches, etc.). Based on the images captured by the cameras, defects or obscuration can be identified.

[0035] In such scenarios, the cameras can include local or distributed groups of pixels located on the primary image sensor of the LIDAR or camera system. Further, the pixels on the primary image sensor for aberration detection can be optically coupled to the lens and / or other optical elements such that an image of the optical component can be reconstructed at the time of image capture. For example, the lens can include one or more microlenses that are coupled to the aberration sensing portion of the primary image sensor.

[0036] In other embodiments, the light emitted from the light source can be coupled into the optical component at one end of the optical component (e.g., along an edge of the optical window). Thereafter, the light can propagate through the body of the optical component via total internal reflection (TIR). If there is no obscuration on the optical component or no defect within the optical component, the light signal can propagate to the opposite end of the optical component (e.g., where it is absorbed by an absorptive baffle, coupled out of the optical component into free space, or detected by a light detector). However, if there is an obscuration on the optical component or a defect within the optical component, the light signal can be redirected (e.g., to a light detector of the camera system / LIDAR device or to a separate light detector for detecting the obscuration / defect) and / or at least partially absorbed. Based on the detection of the light signal (e.g., based on the intensity of the light signal and / or the presence of the light signal), the presence of the defect / obscuration can be identified (e.g., by a computing device executing instructions stored on a non-transitory computer-readable medium).

[0037] In some embodiments, the type of defect / debris present within / on the optical component (e.g., a crack in the optical component vs. mud on the optical component) can also be determined based on the intensity and / or presence of the optical signal. For example, the light source can include one or more light emitting diodes (LEDs) or lasers. In various embodiments, the LEDs or lasers can be positioned adjacent to the optical element (e.g., in an array) and / or embedded within the optical component. Further, the optical quality (e.g., wavelength and / or polarization) of the optical signal emitted by the light source can be predetermined to correspond to various types of debris (e.g., mud, leaves, insects, rain, snow, etc.) that can potentially obscure the optical component. For example, a wavelength can be generated by the light source that is known to reflect off of leaves or generate fluorescence in organic fluorescent compounds. Additionally or alternatively, the optical quality (e.g., wavelength and / or polarization) of the optical signal emitted by the light source can be predetermined to correspond to various types of defects (e.g., cracks, deformations, bubbles, etc.) that can potentially exist within the optical component.

[0038] To achieve total internal reflection, the optical signal can be coupled into the optical component at an angle that achieves total internal reflection based on the refractive indices of the optical component and the surrounding medium (e.g., the optical signal can be coupled into the optical component at a relatively high angle of incidence). In some embodiments, the optical component can be an external or internal lens of a camera system or a LIDAR system. Alternatively, the optical component can be an external optical window (e.g., a dome) placed between the optics of the camera / LIDAR system and the external environment. In embodiments that use an external optical window, the external optical window can be designed to enhance total internal reflection of the optical signal. For example, the external optical window can be relatively thin such that the angle of reflection of the optical signal is relatively shallow with respect to the curvature of the external optical window (e.g., thereby ensuring that the total internal reflection condition is satisfied). In various embodiments, such an external optical window can be shaped as a hemisphere or can be shaped as a semi-cylinder.

[0039] The diagnostic test can be performed at repeated intervals to ensure proper functioning of the LIDAR device / camera. For example, the diagnostic test can be performed every day, every hour, every minute, every thirty seconds, every five seconds, every second, every 500 ms, every 100 ms, every 50 ms, every 10 ms, every 5 ms, every 1 ms, etc. to determine whether a defect is present on or in the corresponding optical component. Upon detection of a defect associated with the corresponding optical component, a corrective measure can be taken. For example, the optical component can be cleaned (e.g., using a windshield wiper), repaired (e.g., by a maintenance technician), replaced (e.g., with a new optical component), realigned, etc. Further, the corrective measure taken can correspond to the type of defect detected. For example, if an obscuration on the optical component is detected, a windshield wiper can be engaged, whereas if a crack in the optical component is detected, a replacement optical component can be ordered and / or installed.

[0040] Still further, in some embodiments, an escalation scheme can also be used. For example, if a defect is detected, a cleaning routine for the optical component can be used. After using the cleaning routine, another diagnostic test can be performed. If the same defect is still present on / in the optical component, a realignment / re-calibration routine can be used. If the defect is still present on / in the optical component after performing the additional diagnostic test, a replacement optical component can be installed. If the defect is still present on / in the optical component after performing yet another diagnostic test, the LIDAR system / camera can be disabled. If the defect is detected to have been corrected during any of the intermediate diagnostic tests, the escalation scheme can be reset and no additional detection events can be performed.

[0041] II. Example Optical System

[0042] Figure 1 An optical system 100 according to an example embodiment is shown. The optical system 100 includes an optical component 110 and one or more light sources 120. In various embodiments, the optical component 110 can include a lens. In such cases, the optical component 110 can include one or more plano-convex lenses, prism lenses, cylindrical lenses, conic lenses, and / or other types of lenses. However, other types of optical components, such as filters, films, mirrors, windows, diffusers, gratings, and / or prisms are also contemplated and possible.

[0043] In example embodiments, the one or more light sources 120 can include a light emitting diode (LED), a laser, an array of LEDs, or an array of lasers. It should be appreciated that other light emitting devices are also contemplated and possible in the context of the present disclosure. In such cases, the light source 120 can be configured to emit a light signal 122. The light signal 122 interacts with the optical component 110 to provide an interacted light signal 124.

[0044] The optical system 100 also includes a detector 130. The detector 130 can be a light sensitive device configured to detect at least a portion of the interacted light signal 124 as a detected light signal 126. In some cases, the detector 130 can include at least one of: a charge-coupled device (CCD), a portion of a CCD, an image sensor of a camera, or a portion of an image sensor of a camera. Additionally or alternatively, the detector 130 can include a silicon photomultiplier (SiPM), an avalanche photodiode (APD), a single-photon avalanche detector (SPAD), a cryogenic detector, a photodiode, or a phototransistor. Other light sensitive devices or systems are also possible and contemplated herein.

[0045] In some embodiments, optical system 100 can include an image sensor 140. For example, image sensor 140 can include a plurality of charge-coupled device (CCD) elements and / or a plurality of complementary metal-oxide-semiconductor (CMOS) elements. In some embodiments, optical system 100 can include a plurality of image sensors. In example embodiments, image sensor 140 can be configured to detect light within an infrared spectrum (e.g., about 700 nanometers to about 1000 nanometers) and / or a visible spectrum (e.g., about 400 nanometers to about 700 nanometers). It is also possible and contemplated herein to use image sensor 140 to sense light within other spectral ranges (e.g., long-wavelength infrared (LWIR) light having a wavelength between 8-12 micrometers).

[0046] Image sensor 140 can be configured (e.g., sized or dimensioned) according to an image sensor format. For example, image sensor 140 can include a full-frame (e.g., 35mm) format sensor. Additionally or alternatively, image sensor 140 can include a “crop sensor” format, such as an APS-C (e.g., 28.4mm diagonal) or one-inch (e.g., 15.86mm diagonal) format. Other image sensor formats are also contemplated and possible within the scope of the present disclosure.

[0047] Optical system 100 additionally includes a controller 150. In some embodiments, controller 150 can be a readout integrated circuit (ROIC) electrically coupled to image sensor 140. Controller 150 includes at least one of a field-programmable gate array (FPGA) or an application-specific integrated circuit (ASIC). Additionally or alternatively, controller 150 can include one or more processors 152 and a memory 154. One or more processors 152 can include a general-purpose processor or a special-purpose processor (e.g., a digital signal processor, etc.). One or more processors 152 can be configured to execute computer-readable program instructions stored in memory 154. In some embodiments, one or more processors 152 can execute program instructions to provide at least some of the functionality and operations described herein.

[0048] Memory 154 can include or take the form of one or more computer-readable storage media readable and / or accessible by one or more processors 152. The one or more computer-readable storage media can include volatile and / or non-volatile storage components, such as optical, magnetic, organic, or other storage or disk storage that can be integrated in whole or in part with at least one of one or more processors 152. In some embodiments, memory 154 can be implemented using a single physical device (e.g., one optical, magnetic, organic, or other storage or disk storage unit), while in other embodiments, memory 154 can be implemented using two or more physical devices.

[0049] As described above, the memory 154 may include computer-readable program instructions related to the operation of the optical system 100. The at least one processor 152 executes the instructions stored in the at least one memory 154 to perform the operations.

[0050] The operations include causing one or more light sources 120 to emit light signals 122. In some embodiments, light signals 122 may be emitted through optical component 110 and toward environment 10 of optical system 100.

[0051] Operations also include receiving a detected light signal 126 from a detector 130 .

[0052] Operations also include determining that one or more defects 118 are associated with the optical component 110 (e.g., present in the body 116 of the optical component 110 or on a surface of the optical component 110 (including the first optical component surface 112 and / or the second optical component surface 114)) based on the detected light signal 126.

[0053] Figure 2A An optical system 200 is shown according to an example embodiment. Optical system 200 can be similar or identical to optical system 100. Some embodiments can include a small camera and LED illuminator placed at or near the focal plane of the image sensor. In such cases, the image plane may be sparse enough to provide space for the occlusion detection camera without causing substantial occlusion in the image.

[0054] For example, in some embodiments, the optical system 200 can include an optical axis 206. The optical system 200 can also include a focal length 204 along the optical axis 206 that defines a focal plane 202. In various embodiments, the optical system 200 can include a plurality of optical elements (e.g., lenses) 110b-110g. For example, the optical elements 110b-110g can include lenses of an optical lens group.

[0055] In some embodiments, image sensor 140 may be arranged along focal plane 202. In such a case, detector 130 may also be arranged along focal plane 202.

[0056] like Figure 2A As shown, in some embodiments, the detector 130 may be arranged to detect the detected light signal 126 along a light detection axis, wherein the light detection axis is arranged at a non-zero offset angle 210 relative to the optical axis 206 (eg, at least 5 degrees off-axis).

[0057] Figure 2B shows a schematic diagram according to an example embodiment Figure 2Aa portion 220 of the optical system 200. In some embodiments, the image sensor 140 can include a plurality of photodetector elements 222 (e.g., 256 pixels, 1000 pixels, up to 20 megapixels or more). In such cases, the detector 130 can include at least a portion of the photodetector elements 222. For example, the detector 130 can include 100 x 100 pixels of a megapixel-level image sensor array. It should be appreciated that the detector 130 can include more or fewer photodetector elements of the entire image sensor 140.

[0058] Figure 2C illustrates a portion 230 of the optical system 200 in accordance with example embodiments. Figure 2A Figure 2C As shown, the image sensor 140 can include a plurality of detectors (e.g., detector 130a and detector 130b). For example, the plurality of detectors can correspond to a plurality of pixels of the image sensor 140.

[0059] Figure 2D illustrates a portion 240 of the optical system 200 in accordance with example embodiments. Figure 2A Figure 2D As shown, the detector 130 can include a first optical filter 242 on a first region of the detector and a second optical filter 244 on a second region of the detector 130. In such cases, the first optical filter 242 and the second optical filter 244 can be configured to select different wavelength ranges (e.g., spectral passbands).

[0060] In some embodiments, the detector 130 can include one or more microlenses 246. The microlens(s) 246 can be optically coupled to the detector 130, the first optical filter 242, and / or the second optical filter 244.

[0061] In some embodiments, the wavelength range corresponding to the first optical filter 242 can include wavelengths of the optical signal 122. Additionally or alternatively, the wavelength range corresponding to the second optical filter 244 can be configured to not include wavelengths of the optical signal 122. In such cases, the operations performed by the controller 150 can further include comparing a first image portion provided by the first region of the detector 130 to a second image portion provided by the second region of the detector 130. Based on the comparison, a defect type of at least one of the one or more defects (e.g., a scratch, a bug, dirt, water, snow, a crack, etc.) can be determined.

[0062] Figure 2E illustrates a portion 240 of the optical system 200 in accordance with example embodiments. Figure 2A ​​a portion 250 of the optical system 200. In some embodiments, the wavelength of the optical signal 122 can correspond to an excitation wavelength of an organic fluorescent compound (e.g., a fluorophore). In such cases, the detector 130 can include a filter (e.g., a first filter 242) that passes an emission wavelength of the organic fluorescent compound while blocking the excitation wavelength of the organic fluorescent compound. In such cases, at least a portion of the detected optical signal 126 can include the emission wavelength. In some embodiments, the operations can further include determining, based on the detected optical signal 126, that one or more organic fluorescent compounds (e.g., the defect 118) are present on the surface of the optical component 110a. Such features can provide information about whether the defect 118 can be an insect (e.g., a firefly “spatter”) having a particular organic fluorescent compound.

[0063] Figure 3A An optical system 300 according to an example embodiment is shown. The optical system 300 can be similar or identical to the optical system 100 and / or the optical system 200 shown and described with reference to FIGS. 1A-1E and 2A-2E in various respects. Figure 1 and 2A In some embodiments, the optical signal 122 can be directed into the body 116 of the optical element 110a, thereby reflecting within the body 116 of the optical element 110a via total internal reflection 302. In some embodiments, the optical signal 122 can be directed into the body 116 at a desired angle to achieve the total internal reflection 302.

[0064] In example embodiments, the one or more light sources 120 can be positioned proximate to a first end 304 of the optical component 110a. In such cases, the optical signal 122 can be optically coupled into the optical component 110a via the first end 304.

[0065] Figure 3B An optical system 300 according to an example embodiment is shown. Figure 3A a portion 320 of the optical system 300. In such cases, the detector 130 can be positioned at a second end 322 of the optical component 110a opposite the first end 304 of the optical component 110a.

[0066] Additionally or alternatively, the optical component 110a can be attached to form over the one or more light sources 120 such that the one or more light sources 120 are at least partially embedded within the optical component 110a. Thus, the one or more light sources 120 can be embedded within or otherwise optically and physically coupled to the optical component 110a.

[0067] Figure 3C An optical system 300 according to an example embodiment is shown. Figure 3Apart of the optical system 300. In some examples, the optical component 110a can be an external optical window (e.g., a transparent housing). In such cases, the external optical window can be curved (e.g., hemispherical or semi-cylindrical). It should be appreciated that the external optical window can have other shapes or forms.

[0068] Figure 4 Various images 400 of optical components are shown, in accordance with example embodiments. The images 400 can include output from an image sensor (e.g., the image sensor 140) and / or a detector (e.g., the detector 130). As an example, the images 400 can include images from an interior surface of the optical component 110a. However, other optical components can be imaged, as described elsewhere herein.

[0069] In various embodiments, the images 400 can show a windowless 402, a white diffuser 404, a water droplet 406, a ruler 408, a clean window 410, a dirty window 412, and other foreign objects 414. In some embodiments, the various images 400 can be subject to image analysis by the controller 150 and / or another computing device. In such cases, the controller 150 and / or another computing device can determine a type of occlusion (e.g., water droplet, clean / dirty window, etc.) based on the image analysis.

[0070] In some embodiments, one or more sensor units in conjunction with the optical system 100, the optical system 200, and / or the optical system 300 can be attached or otherwise mounted to a vehicle, as described below.

[0071] III. Example Vehicles

[0072] Figure 5A , 5B Figures 5C, 5D, and 5E show a vehicle 500, in accordance with example embodiments. The vehicle 500 can be a semi-autonomous or fully-autonomous vehicle. While Figure 5 shows the vehicle 500 as a car (e.g., a passenger car), it should be appreciated that the vehicle 500 can include other types of autonomous vehicles, robots, or drones that are capable of navigating in their environment using sensors and other information about their environment.

[0073] The vehicle 500 can include one or more sensor systems 502, 504, 506, 508, and 510. In some embodiments, the sensor systems 502, 504, 506, 508, and 510 can include sensors that are similar to the sensors described above with respect to the optical system 100, the optical system 200, and / or the optical system 300. Figure 1 , 2A- the optical systems 100, 200, and / or 300 shown and described in connection with 2E and 3A-3C. In other words, the optical systems described elsewhere herein can be coupled to the vehicle 500 and / or can be used in conjunction with various operations of the vehicle 500. As an example, the optical systems 100, 200, and / or 300 can be implemented in or in conjunction with the sensor systems 502, 504, 506, 508, and 510, which can be used for autonomous driving or other types of navigation, planning, and / or mapping operations of the vehicle 500.

[0074] While one or more of the sensor systems 502, 504, 506, 508, and 510 are shown at certain locations on the vehicle 500, it should be understood that more or fewer sensor systems can be used for the vehicle 500. Moreover, the locations of such sensor systems can be adjusted, modified, or otherwise changed as compared to the locations of the sensor systems shown in 5A, 5B, 5C, 5D, and 5E. Figure 5A , 5B

[0075] In some embodiments, one or more of the sensor systems 502, 504, 506, 508, and 510 can additionally or alternatively include a LIDAR sensor. For example, a LIDAR sensor can include a plurality of light-emitting devices arranged at a range of angles relative to a given plane (e.g., an x-y plane). For example, one or more of the sensor systems 502, 504, 506, 508, and 510 can be configured to rotate about an axis (e.g., a z-axis) that is perpendicular to the given plane to illuminate the environment surrounding the vehicle 500 with light pulses. Based on detecting various aspects of the reflected light pulses (e.g., elapsed time of flight, polarization, intensity, etc.), information about the environment can be determined.

[0076] In example embodiments, the sensor systems 502, 504, 506, 508, and 510 can be configured to provide respective point cloud information that can be related to physical objects within the environment of the vehicle 500. While the vehicle 500 and the sensor systems 502, 504, 506, 508, and 510 are shown as including certain features, it should be understood that other types of sensor systems can be considered within the scope of the present disclosure.

[0077] ​Example embodiments can include systems having multiple light emitting devices. The system can include a transmit block of a LIDAR device. For example, the system can be or can be part of a LIDAR device of a vehicle (e.g., a car, truck, motorcycle, golf cart, aircraft, boat, etc.). Each light emitting device of the multiple light emitting devices is configured to emit light pulses along a respective beam elevation angle. The respective beam elevation angle can be based on a reference angle or a reference plane, as described elsewhere herein. In some embodiments, the reference plane can be based on an axis of motion of the vehicle 500.

[0078] While LIDAR systems having a single light emitting device are described and shown herein, LIDAR systems having multiple light emitting devices (e.g., light emitting devices having multiple laser stripes on a single laser die) can also be considered. For example, the light pulses emitted by one or more laser diodes can be controllably directed around the environment of the system. For example, the emission angle of the light pulses can be adjusted by a scanning device such as a mechanical scanning mirror and / or a rotating motor. For example, the scanning device can rotate in a reciprocating motion about a given axis and / or rotate about a vertical axis. In another embodiment, the light emitting device can emit light pulses to a spinning prism mirror that can cause the light pulses to be emitted into the environment based on the angle of the prism mirror angle as the spinning prism mirror interacts with each light pulse. Additionally or alternatively, scanning optics and / or other types of electro-optical mechanical devices can cause the light pulses to scan around the environment.

[0079] In some embodiments, as described herein, the single light emitting device can emit light pulses according to a variable emission plan and / or at variable power per emission. That is, the emission power and / or timing of each laser pulse or emission can be based on the respective elevation angle of the emission. Further, the variable emission plan can be based on providing a desired vertical spacing at a given distance from the LIDAR system or from a surface (e.g., a front bumper) of a given vehicle supporting the LIDAR system. As an example, when light pulses from the light emitting device are directed downward, the power per emission can be reduced as the expected maximum distance to a target is shorter. Conversely, light pulses emitted by the light emitting device at an elevation angle above the reference plane can have a relatively higher power per emission to provide a sufficient signal-to-noise ratio to adequately detect pulses traveling a longer distance.

[0080] In some embodiments, the power / energy per emission can be controlled in a dynamic manner per emission. In other embodiments, the power / energy per emission can be controlled for a continuous group of several pulses (e.g., 10 light pulses). That is, the characteristics of a string of light pulses can change on a per pulse basis and / or on a per several pulses basis.

[0081] While Figures 5A-5EVarious LIDAR sensors are shown attached to the vehicle 500, but it should be understood that the vehicle 500 can incorporate other types of sensors, such as cameras, ultrasonic sensors, and / or radar sensors.

[0082] IV. Example Methods

[0083] Figure 6 A method 600 according to example embodiments is shown. It should be understood that the method 600 can include fewer or more steps or blocks than those expressly shown or otherwise disclosed herein. Further, the various steps or blocks of the method 600 can be performed in any order and each step or block can be performed one or more times. In some embodiments, some or all of the blocks or steps of the method 600 can involve elements of the optical systems 100, 200, 300 and / or the vehicle 500 shown and described with respect to Figure 1 、 2A - the optical systems 100, 200, 300 and / or elements of the vehicle 500 shown and described with respect to 2E, 3A-3C, and 5A-5E.

[0084] Block 602 includes causing one or more light sources (e.g., the light source 120) to emit a light signal (e.g., the light signal 122). Causing the light source to emit the light signal can include causing a pulse generator circuit to transmit a current or voltage pulse to the light source to generate one or more light pulses. In some embodiments, the light signal 122 interacts with an optical component (e.g., the optical component 110) of an optical system (e.g., the optical system 100) to provide an interacted light signal (e.g., the interacted light signal 124).

[0085] Block 604 includes detecting, at a detector (e.g., the detector 130) disposed within an enclosure of the optical system, at least a portion of the interacted light signal as a detected light signal (e.g., the detected light signal 126). In example embodiments, receiving the detected light signal can include receiving information indicative of one or more defects on the optical component. In such cases, the information can include an image of the optical component and / or information about the intensity of photons from the environment of the optical system.

[0086] Block 606 includes determining, based on the detected light signal, that at least one defect (e.g., the defect 118) is associated with the optical component. As an example, the defect can be present in a body (e.g., the body 116) of the optical component or on a surface (e.g., the first optical component surface 112 or the second optical component surface 114) of the optical component. In some embodiments, determining the at least one defect can include performing image analysis (e.g., object recognition) on information received from the detector or image sensor. As an example, the detector or image sensor can provide an image, such as the image shown and described with respect to Figure 4

[0087] ​In some embodiments, the method 600 can additionally include taking a corrective action if it is determined that one or more defects are present in the body of the optical component or on a surface of the optical component.

[0088] In various embodiments, taking the corrective action can include at least one of cleaning, repairing, recalibrating, replacing, realigning, or deactivating the detector or the optical component.

[0089] In example embodiments, causing the one or more light sources to emit the light signal can include causing the one or more light sources to emit the light signal toward the body of the optical component at an angle such that the light signal is reflected within the body of the optical component via total internal reflection.

[0090] Additionally or alternatively, the method 600 can include determining a defect type of the at least one defect, wherein the defect type includes at least one of a scratch, a crack, a smudge, a deformation, a debris, a bubble, an impurity, a deterioration, a discoloration, an imperfect transparency, a warp, or a condensation (e.g., a water droplet).

[0091] The specific arrangements illustrated in the drawings are to be considered in a descriptive sense only and not limiting. It is to be understood that other embodiments can include the same elements as found in the drawings, without doing temporal reference thereto. Furthermore, some of the elements shown can be combined or omitted. Still further, illustrative embodiments can include elements not shown in the drawings.

[0092] Steps or blocks representing information processing can correspond to a specific logical function that can be configured to perform the methods or techniques described herein. Alternatively or additionally, steps or blocks representing information processing can correspond to a module, segment, or portion of program code including related data. Program code can include one or more instructions executable by a processor for implementing specific logical functions or actions in the methods or techniques. Program code and / or related data can be stored on any type of computer readable medium, such as a storage device including a disk, hard drive, or other storage medium.

[0093] Computer readable media can also include non-transitory computer readable media, such as computer readable media that store data for short periods of time, like register memory, processor cache, and random access memory (RAM). Computer readable media can also include non-transitory computer readable media that store program code and / or data for longer periods of time, like secondary or persistent long term storage, like read only memory (ROM), optical or magnetic disks, compact disc read only memories (CD-ROMs). Computer readable media can also be any other volatile or non-volatile storage systems. For example, computer readable media can be considered computer readable storage media or a tangible storage device.

[0094] While various examples and embodiments have been disclosed, other examples and embodiments will be apparent to those of ordinary skill in the art. The various disclosed examples and embodiments are for purposes of illustration and are not intended to be limiting, with the true scope being indicated by the appended claims.

Claims

1. An optical system comprising: Optical components; one or more light sources configured to emit light signals, wherein the light signals interact with the optical component to provide interacting light signals; and a detector configured to detect at least a portion of the interacting light signal as a detected light signal; and A controller comprising at least one processor and at least one memory, wherein the at least one processor executes instructions stored in the at least one memory to perform operations, the operations comprising: causing the one or more light sources to emit light signals; and One or more defects are determined to be associated with the optical component based on a detected optical signal from the detector, and a defect type of at least one of the one or more defects associated with the optical component is determined from a plurality of defect types based on one or more optical qualities of the detected optical signal, wherein the one or more optical qualities include intensity, wavelength, or polarization of the detected optical signal.

2. The optical system according to claim 1, wherein The optical system further comprises: optical axis; a focal length along the optical axis defining a focal plane; and An image sensor is arranged along the focal plane, wherein the detector is arranged along the focal plane.

3. The optical system according to claim 2, wherein: The image sensor comprises a plurality of photodetector elements, wherein the detector comprises at least a portion of the photodetector elements.

4. The optical system according to claim 2, wherein: The detector is arranged to detect the detected light signal along a light detection axis, wherein the light detection axis is at least 5 degrees off-axis relative to the optical axis.

5. The optical system according to claim 1, wherein The one or more light sources include a light emitting diode (LED), a laser, an LED array, or a laser array.

6. The optical system according to claim 1, wherein: The light signal is directed into the optical component at an angle such that the light signal is reflected within the optical component via total internal reflection.

7. The optical system according to claim 6, wherein: The one or more light sources are located proximate a first end of the optical component, and wherein the optical signal is coupled into the optical component via the first end.

8. The optical system according to claim 7, wherein: The detector is positioned at a second end of the optical component, wherein the second end is opposite the first end.

9. The optical system according to claim 1, wherein: The one or more light sources are at least partially embedded within the optical component.

10. The optical system according to claim 1, wherein: The optical component comprises an external optical window, wherein the external optical window has a curved shape.

11. The optical system according to claim 1, wherein: The detector includes at least one of: a charge coupled device (CCD), a portion of a CCD, an image sensor of a camera, or a portion of an image sensor of a camera.

12. The optical system according to claim 1, wherein: The detector includes a silicon photomultiplier (SiPM), an avalanche photodiode (APD), a single photon avalanche detector (SPAD), a cryogenic detector, a photodiode, or a phototransistor.

13. The optical system of claim 1 , further comprising a first filter optically coupled to a first region of the detector and a second filter optically coupled to a second region of the detector, wherein The first optical filter and the second optical filter select different wavelength ranges, wherein the wavelength range selected by the first optical filter includes the wavelength of the optical signal, wherein the wavelength range selected by the second optical filter does not include the wavelength of the optical signal, and wherein the operation further comprises: comparing a first image portion provided by a first region of the detector with a second image portion provided by a second region of the detector; and A defect type of at least one of the one or more defects is determined based on the comparison.

14. The optical system according to claim 1, wherein: The wavelength of the light signal corresponds to an excitation wavelength of an organic fluorescent compound, wherein the detector includes a filter that passes an emission wavelength of the organic fluorescent compound and blocks an excitation wavelength of the organic fluorescent compound, wherein at least a portion of the detected light signal includes the emission wavelength, and wherein the operations further comprise: The presence of one or more organic fluorescent compounds on the surface of the optical component is determined based on the detected light signal.

15. An optical detection method, comprising: causing one or more light sources to emit a light signal, wherein the light signal interacts with an optical component of the optical system to provide an interacting light signal; detecting at least a portion of the interacting light signal as a detected light signal by a detector disposed within a housing of the optical system; and One or more defects are determined to be associated with the optical component based on the detected optical signal, and a defect type of at least one of the one or more defects associated with the optical component is determined from a plurality of defect types based on one or more optical qualities of the detected optical signal, wherein the one or more optical qualities include intensity, wavelength, or polarization of the detected optical signal.

16. The method according to claim 15, further comprising: Corrective action is taken in response to determining that one or more defects are associated with the optical element.

17. The method according to claim 16, wherein Corrective actions taken include: At least one of the detector or the optical component is cleaned, repaired, recalibrated, replaced, realigned, or decommissioned.

18. The method according to claim 15, wherein Causing the one or more light sources to emit light signals includes causing the one or more light sources to emit light signals toward the optical component at an angle such that the light signals are reflected within a body of the optical component via total internal reflection.

19. The method according to claim 15, wherein The defect type includes at least one of the following: scratches, cracks, stains, deformation, chips, bubbles, impurities, deterioration, discoloration, imperfect transparency, warping, or condensation.

20. A vehicle comprising: at least one optical system, the optical system comprising: Optical components; one or more light sources configured to emit light signals, wherein the light signals interact with the optical component to provide interacting light signals; and a detector configured to detect at least a portion of the interacting light signal as a detected light signal; and A controller comprising at least one processor and at least one memory, wherein the at least one processor executes instructions stored in the at least one memory to perform operations, the operations comprising: causing the one or more light sources to emit light signals; receiving a detected light signal from the detector; and One or more defects are determined to be associated with the optical component based on the detected optical signal, and a defect type of at least one of the one or more defects associated with the optical component is determined from a plurality of defect types based on one or more optical qualities of the detected optical signal, wherein the one or more optical qualities include intensity, wavelength, or polarization of the detected optical signal.

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