Illumination control for imaging systems with multiple image sensors

Abstract

The present invention is entitled "Illumination Control for Imaging Systems with Multiple Image Sensors". Embodiments of the present disclosure generally relate to illumination synchronization in a multi-imager environment. Embodiments include systems, methods, computer program products, and apparatus configured to operate a near-field illumination source associated with a near-field image sensor based on a first illumination pulse train. An exposure period for a far-field image sensor is determined and one or more characteristics of the first illumination pulse train are modified to accommodate the exposure period for the far-field image sensor.

Description

Technical Field

[0001] Embodiments of the present disclosure relate generally to imaging systems having multiple image sensors, and more particularly to illumination control of image sensors for imaging systems. Background Art

[0002] Imaging devices and systems have found applications in areas more complex and advanced than simple photography. There is a constant need to improve the imaging capabilities of these devices and systems to accommodate supporting new capabilities. With currently available imaging systems, factors such as miniaturized form factors have led to an increase in interference between the components of the imaging systems. In such systems, it remains challenging to operate these components in a synchronized manner to prevent any adverse effects on each other's capabilities. Summary of the invention

[0003] In general, the embodiments of the present disclosure provided herein are configured for illumination control and synchronization in a multi-imager environment. Other specific implementations of one or more of the alternative illuminator assemblies and / or alternative illumination imaging systems and devices will be or will become apparent to those skilled in the art by examining the following drawings and detailed description. All such additional specific implementations included within this specification are intended to be within the scope of the present disclosure and are protected by the following claims.

[0004] According to some exemplary embodiments, an imaging system is provided herein. In an exemplary embodiment, the imaging system includes a first illumination source associated with a first image sensor, the first illumination source being configured to operate based on a first illumination pulse train. The imaging system also includes a second image sensor and a controller, the controller being communicatively coupled to each of the first illumination source, the first image sensor, and the second image sensor. In some exemplary embodiments, the controller is configured to determine a first exposure period of the second image sensor and modify one or more characteristics of the first illumination pulse train to accommodate the first exposure period of the second image sensor.

[0005] Additionally or alternatively, in some embodiments of the imaging system, in order to modify the one or more characteristics of the first illumination pulse train, the controller is further configured to insert at least one additional illumination pulse into the first illumination pulse train so that one of the start time period or the end time period of the illumination cycle of the at least one additional illumination pulse is aligned with a corresponding one of the start time period or the end time period of the first exposure cycle of the second image sensor.

[0006] Additionally or alternatively, in some embodiments of the imaging system, in order to modify the one or more characteristics of the first illumination pulse train, the controller is further configured to insert at least one additional illumination pulse into the first illumination pulse train such that the illumination of the first image sensor corresponding to the at least one additional illumination pulse overlaps in time with the autofocus period of the second image sensor.

[0007] Additionally or alternatively, in some embodiments of the imaging system, in order to modify the one or more characteristics of the first illumination pulse train, the controller is further configured to increase a timing delay between a pair of temporally subsequent illumination pulses of the first illumination pulse train so that one of the start time period or the end time period of the first exposure period is aligned with a corresponding one of the start time period or the end time period of the increased timing delay.

[0008] Additionally or alternatively, in some embodiments of the imaging system, the first image sensor is exposed during at least a second exposure period. In some exemplary embodiments, the exposure of the first image sensor during the second exposure period begins simultaneously with the start time period of the first illumination pulse of the first illumination pulse train, and the end time period of the second exposure period extends beyond the end time period of the first illumination pulse of the first illumination pulse train.

[0009] Additionally or alternatively, in some embodiments of the imaging system, the controller is further configured to obtain an image frame captured by the exposure of the second image sensor during the first exposure period. In some exemplary embodiments, the controller is further configured to determine a brightness of the image frame and activate a second illumination source associated with the second image sensor based on the determined brightness of the image frame, wherein the second illumination source is configured to operate based on a second illumination pulse train.

[0010] Additionally or alternatively, in some embodiments of the imaging system, exposure of the first image sensor begins simultaneously with activation of the first illumination source.

[0011] Additionally or alternatively, in some embodiments of the imaging system, the second image sensor remains deactivated during a first illumination period of a first illumination pulse of the first illumination pulse train. Additionally or alternatively, in some embodiments, the second image sensor is exposed during a portion of a second illumination period of a second illumination pulse of the first illumination pulse train.

[0012] In some exemplary embodiments, an imaging method is provided. The method can be implemented using any of numerous implementations, such as via hardware, software, and / or firmware of a multi-sensor imaging engine and / or a multi-sensor imaging device as described herein. In some exemplary implementations of the method, the exemplary method includes operating a first illumination source associated with a first image sensor based on a first illumination pulse train. The exemplary method also includes determining a first exposure period of a second image sensor and modifying one or more characteristics of the first illumination pulse train to accommodate the first exposure period of the second image sensor.

[0013] Additionally or alternatively, in some embodiments of the method, modifying the one or more characteristics of the first illumination pulse train includes inserting at least one additional illumination pulse into the first illumination pulse train so that one of the start time period or the end time period of the illumination cycle of the at least one additional illumination pulse is aligned with a corresponding one of the start time period or the end time period of the first exposure cycle of the second image sensor.

[0014] Additionally or alternatively, in some embodiments of the method, modifying the one or more characteristics of the first illumination pulse train includes inserting at least one additional illumination pulse into the first illumination pulse train such that illumination of the first image sensor corresponding to the at least one additional illumination pulse temporally overlaps with an autofocus period of the second image sensor.

[0015] Additionally or alternatively, in some embodiments of the method, modifying the one or more characteristics of the first illumination pulse train includes increasing a timing delay between a pair of temporally subsequent illumination pulses of the first illumination pulse train so that one of the start time period or the end time period of the first exposure period is aligned with a corresponding one of the start time period or the end time period of the increased timing delay.

[0016] Additionally or alternatively, in some embodiments of the method, the method further comprises causing exposure of the first image sensor during at least a second exposure period. In some exemplary embodiments, exposure of the first image sensor during the second exposure period begins simultaneously with a start time period of a first illumination pulse of the first illumination pulse train. In some exemplary embodiments, an end time period of the second exposure period extends beyond an end time period of the first illumination pulse of the first illumination pulse train.

[0017] Additionally or alternatively, in some embodiments of the method, the method further comprises obtaining an image frame captured by the exposure of the second image sensor during the first exposure period. The exemplary method further comprises determining a brightness of the image frame and activating a second illumination source associated with the second image sensor based on the determined brightness of the image frame, the second illumination source being configured to operate based on a second illumination pulse train.

[0018] In some exemplary embodiments, an apparatus is provided. In an exemplary embodiment, the apparatus includes a memory configured to store executable instructions; and one or more processors. In some exemplary embodiments, the one or more processors are configured to execute the executable instructions to control the operation of a first illumination source associated with a first image sensor based on a first illumination pulse train. In some exemplary embodiments, the one or more processors are further configured to determine a first exposure period of a second image sensor and modify one or more characteristics of the first illumination pulse train to accommodate the first exposure period of the second image sensor.

[0019] Additionally or alternatively, in some embodiments of the device, in order to modify the one or more characteristics of the first illumination pulse train, the one or more processors are further configured to insert at least one additional illumination pulse into the first illumination pulse train so that one of the start time period or the end time period of the illumination cycle of the at least one additional illumination pulse is aligned with a corresponding one of the start time period or the end time period of the first exposure cycle of the second image sensor.

[0020] Additionally or alternatively, in some embodiments of the device, in order to modify the one or more characteristics of the first illumination pulse train, the one or more processors are further configured to insert at least one additional illumination pulse into the first illumination pulse train so that the illumination of the first image sensor corresponding to the at least one additional illumination pulse overlaps in time with the autofocus period of the second image sensor.

[0021] Additionally or alternatively, in some embodiments of the device, in order to modify the one or more characteristics of the first illumination pulse train, the one or more processors are further configured to increase a timing delay between a pair of temporally subsequent illumination pulses of the first illumination pulse train so that one of the start time period or the end time period of the first exposure period is aligned with a corresponding one of the start time period or the end time period of the increased timing delay.

[0022] Additionally or alternatively, in some embodiments of the apparatus, the one or more processors are further configured to obtain an image frame captured by the exposure of the second image sensor during the first exposure period. In some exemplary embodiments of the apparatus, the one or more processors are further configured to determine a brightness of the image frame and activate a second illumination source associated with the second image sensor based on the determined brightness of the image frame, wherein the second illumination source is configured to operate based on a second illumination pulse train. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Having thus generally described embodiments of the present disclosure, reference will now be made to the accompanying drawings, which are not necessarily drawn to scale, and in which:

[0024] Figure 1A shows a block diagram of an exemplary multi-sensor imaging system according to an exemplary embodiment of the present disclosure;

[0025] Figure 1B shows a block diagram of an exemplary multi-sensor imaging engine according to an exemplary embodiment of the present disclosure;

[0026] Figure 2 A block diagram of an exemplary multi-sensor imaging device according to an exemplary embodiment of the present disclosure is shown;

[0027] Figure 3 shows a visualization of a field of view associated with an exemplary multi-sensor imaging device according to an exemplary embodiment of the present disclosure;

[0028] Figure 4 shows a visualization of a first illumination produced by an exemplary multi-sensor imaging system according to an exemplary embodiment of the present disclosure;

[0029] Figure 5 shows a visualization of a second illumination produced by an exemplary multi-sensor imaging system according to an exemplary embodiment of the present disclosure;

[0030] Figure 6 illustrates a timing diagram associated with operational functionality of an exemplary multi-sensor imaging system according to an exemplary embodiment of the present disclosure;

[0031] Figure 7 A flow chart depicting exemplary operations of a process for lighting control in a multi-imager environment is shown according to an exemplary embodiment of the present disclosure;

[0032] Figure 8A flow chart depicting exemplary operations of a process for modifying one or more characteristics of a first illumination pulse train to accommodate a first exposure period of a second image sensor of an exemplary multi-sensor imaging system is shown in accordance with an exemplary embodiment of the present disclosure;

[0033] Fig. 9 A flow chart depicting exemplary operations of another process for modifying one or more characteristics of a first illumination pulse train to accommodate a first exposure period of a second image sensor of an exemplary multi-sensor imaging system is shown in accordance with an exemplary embodiment of the present disclosure;

[0034] Fig.10 A flow chart depicting exemplary operations of another process for modifying one or more characteristics of a first illumination pulse train to accommodate a first exposure period of a second image sensor of an exemplary multi-sensor imaging system is shown in accordance with an exemplary embodiment of the present disclosure;

[0035] Fig.11 illustrates a timing diagram associated with operational functionality of an exemplary multi-sensor imaging system for flicker reduction according to an exemplary embodiment of the present disclosure;

[0036] Fig. 12A , Fig. 12B and Fig. 12C An exemplary workflow of a symbol decoding process according to an exemplary embodiment of the present disclosure is shown;

[0037] Fig.13 An exemplary workflow of a flicker reduction process according to an exemplary embodiment of the present disclosure is shown; and

[0038] Fig.14 An exemplary workflow of a flicker reduction process for extended far-field exposure of an imaging device according to an exemplary embodiment of the present disclosure is shown. DETAILED DESCRIPTION

[0039] Embodiments of the present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all, embodiments of the present disclosure are shown. Indeed, embodiments of the present disclosure can be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that the present disclosure will satisfy applicable legal requirements. Throughout the text, like reference numerals refer to like elements.

[0040] Imaging devices, such as tag readers, are used in a variety of scenarios, each of which requires a set of specific imaging requirements to be met so that operations associated with the tag reader, such as symbol decoding, can be performed continuously. Additionally, certain safety requirements, such as those related to the operator of the tag reader, must be met to ensure compliance with statutory regulations. Tag readers typically need to scan symbols attached to surfaces from a close range to successfully decode them. However, in some environments, such as warehouses, it is not possible to scan and successfully decode symbols attached to packages and consignments by reaching each consignment from a close range. Therefore, an extended range tag reader is provided that does not require an operator to individually reach each consignment from a close range. Due to the far-field scanning capabilities of the extended range reader, such an extended range tag reader is able to scan multiple symbols from a single operator position. Such tag readers include multiple image sensors and associated optical devices to provide these capabilities.

[0041] The lighting requirements of these sensors may vary greatly. For example, one or more image sensors of a tag reader may require illumination even during data readout, while other sensors may not have such a requirement. Therefore, keeping the light source of one image sensor activated for a longer period may result in interference with the exposure period of another sensor that is not expected to be illuminated. Such interference may produce images that are defective in terms of one or more imaging characteristics, thereby adversely affecting the resulting image processing task. This problem is particularly prevalent in miniaturized imaging devices, in which sensors, illumination sources, and other optical devices and components are closely arranged. In addition, in the context of a multi-imager environment (e.g., including multiple imagers and / or multiple light sources), original specific implementations such as capturing images by alternating between imagers and / or light sources exacerbate the flicker effect, and therefore exacerbate the negative effects associated therewith.

[0042] Often in scenarios where the image sensors are of different types, it is difficult to synchronize the illumination of the sensors for successful operation. For example, when a tag reader includes a rolling shutter sensor for imaging in the far field and a global shutter sensor for imaging in the near field, it is difficult to ensure optimal illumination conditions for the global shutter sensor due to the extended illumination time of the rolling shutter during data readout. This results in undesirable effects such as the snappiness of the image captured by the global shutter sensor. In addition, the extended illumination time can also cause heat generation, thereby affecting the thermal management system in the barcode scanner. Furthermore, in outdoor environments, illumination may not always be required for far field imaging because there is sufficient ambient light available. As a result, the aimer of the imaging system may not be distinguishable from the background, requiring rapid focusing to adjust the focus position of the image sensor.

[0043] Additionally, controlling the illumination of such devices can be used to provide a more pleasing visual appearance to the operator. For example, if the illumination pulses are within a certain frequency range (e.g., below a certain threshold frequency), the operator may experience headaches and / or seizures due to visual exposure to the illumination. In a multi-imager context with multiple illumination sources, each illumination source should be configured accordingly to prevent such negative health effects and undesirable visual appearances. Regardless, if these illumination sources are cycled through and / or otherwise frequently switched between, the operator may experience a "flicker" effect that may be undesirable or also harmful.

[0044] Some embodiments described herein relate to a dual illumination framework for a multi-sensor imaging system, the multi-sensor imaging system comprising multiple illumination sources and multiple image sensors. Some embodiments described herein utilize a first illumination source and a first image sensor to capture an image during one or more illumination pulses of an illumination pulse train associated with the first illumination source. The embodiments also utilize a second image sensor to capture an image, wherein an exposure period of the second image sensor is taken into account to modify the first illumination pulse train so that the illumination of the first illumination source does not introduce any undesirable effects in the image captured by the second image sensor. In addition, the illumination of the second image sensor is timed in a manner that does not affect the image captured by the first image sensor.

[0045] In some embodiments, one or more events may be triggered indicating a situation requiring activation of a second illumination source. In this regard, the second illumination source may generate a second illumination for illuminating a second field of view associated with a second image sensor. In one such exemplary context, activation of the second illumination source is triggered after determining that an object is not detected within an image captured in a first field of view using the first illumination source and / or in a second field of view illuminated using ambient light, and thus the object may be at a greater distance from the imaging device. Activation of the second illumination source may be triggered in response to detection of one or more events and / or situations, such as in response to processing one or more previously captured images to determine that a threshold number of images have been captured, and that an object is not detected within an image captured under very low lighting conditions (e.g., below a certain whiteness value threshold).

[0046] In such cases, changing to another illumination source enables triggering of the second image sensor during the illumination pulse of the newly activated second illumination source to improve the effective read range of the device. In embodiments with more than two illumination sources, the same considerations may continue to apply for cycling through more than two illumination sources, such as to narrow the field of view illuminated by each illumination source and extend the effective range of each cycle. Alternatively, one or more illumination sources may be skipped, such as in this case immediately cycling from the widest illumination source to the narrowest illumination source without using one or more intermediate illumination sources.

[0047] Such embodiments provide effective synchronization of illumination sources and flicker reduction and / or flicker elimination while enabling effective and efficient capture of images for processing. Operation of such embodiments captures images in a manner likely to enable successful completion of image processing tasks (such as mark or symbol scanning) while increasing the likelihood that images will be captured within a desired operating timeframe that includes sufficient data for successful processing. By implementing the various exemplary embodiments described herein, the operating efficiency of an imaging device is maintained or improved while addressing challenges caused by the use of multiple sensors and illumination sources.

[0048] In some embodiments, some of the operations described above may be modified or further amplified. In addition, in some embodiments, additional optional operations may also be included. The modification, amplification or addition of the operations described above may be performed in any order and in any combination.

[0049] The technical personnel in the field of the present disclosure will think of many modifications and other embodiments of the present disclosure set forth herein after benefiting from the teachings presented in the foregoing description and the related drawings. Therefore, it should be understood that the embodiments are not limited to the specific embodiments disclosed, and modifications and other embodiments are intended to be included within the scope of the appended claims. In addition, although the above description and the related drawings describe example embodiments in the context of certain example combinations of elements and / or functions, it should be understood that different combinations of elements and / or functions can be provided by alternative embodiments without departing from the scope of the appended claims. In this regard, for example, it is also conceivable to combine elements and / or functions different from those explicitly described above, as can be shown in some of the appended claims. Although specific terms are used herein, they are used only in a general and descriptive sense, not for the purpose of limitation.

[0050] [ definition ]

[0051] The term "illumination" refers to one or more rays of light generated by an illumination source within a defined field of view. In at least one exemplary context, illumination includes one or more illumination pulses generated by a corresponding illumination source. In some embodiments, illumination is generated based on a "defined pulse frequency", which "defined pulse frequency" refers to the rate of illumination pulses generated by the illumination source. Additionally or alternatively, in some embodiments, illumination is generated based on a "defined pulse phase", which "defined pulse phase" refers to an activation period during which the illumination source generates the corresponding illumination.

[0052] Thus, a plurality of illumination pulses having a defined pulse frequency may together constitute an "illumination pulse train". Each illumination pulse may extend in the time domain for a duration called an "illumination period". Thus, an illumination period may refer to a duration during which the amplitude of an illumination pulse remains non-zero. That is, an illumination period of an illumination pulse refers to a period during which the illumination source corresponding to the illumination pulse remains activated.

[0053] In at least one exemplary context, an illumination pulse is associated with an "illumination pulse start time," which refers to electronic management data indicating a time at which a corresponding illumination source will begin to generate an illumination pulse. Additionally or alternatively, in at least one such context, an illumination pulse is associated with an "illumination pulse end time," which refers to electronic management data indicating a time at which a corresponding illumination source will stop generating an illumination pulse.

[0054] The term "start time period of a lighting cycle" refers to a time period of a threshold duration starting from a lighting pulse start time, where the threshold duration may have a configurable value. In at least one exemplary context, the threshold duration may be zero, and thus, the terms start time period of a lighting cycle and lighting pulse start time may refer to the same time instance. Each lighting pulse may have a separate start time period.

[0055] The term "end time period of a lighting cycle" refers to a time period of a threshold duration that ends at a lighting pulse end time, where the threshold duration may have a configurable value. In at least one exemplary context, the threshold duration may be zero, and thus, the terms end time period of a lighting cycle and lighting pulse end time may refer to the same time instance. Each lighting pulse may have a separate end time period.

[0056] The term "illumination source" (also referred to as "illuminator source" or "illuminator") refers to one or more light generating hardware, devices, and / or components configured to produce illumination within a desired field of view. Non-limiting examples of illumination sources include one or more light emitting diodes (LEDs), lasers, and the like.

[0057] The term "near-field illumination source" refers to an illumination source configured to generate illumination to illuminate a near field of view associated with a near-field image sensor. In at least one exemplary context, the near-field illumination source is configured to generate illumination in a wider field of view than a far-field illumination source.

[0058] The term "far-field illumination source" refers to an illumination source configured to generate illumination to illuminate a far field of view associated with a far-field imager. In at least one exemplary context, the far-field illumination source is configured to generate illumination in a narrower field of view than a near-field illumination source.

[0059] The term "near-field illumination" refers to a specific illumination generated by a near-field illumination source. In some embodiments, the near-field illumination is associated with the illumination of the near field of view captured by the near-field image sensor. The term "near-field illumination pulse" refers to an illumination pulse of the near-field illumination associated with the near-field sensor.

[0060] The term "far-field illumination" refers to a specific illumination generated by a far-field illumination source. In some embodiments, the far-field illumination is associated with the illumination of a far field of view captured by a far-field image sensor. The term "far-field illumination pulse" refers to an illumination pulse of the far-field illumination.

[0061] The term "imager" refers to one or more components configured to capture an image representing a particular field of view. In at least one exemplary context, the imager includes at least one optical component (e.g., a lens and / or associated housing) that defines the particular field of view. Additionally or alternatively, in at least one exemplary context, the imager includes an image sensor configured to output an image based on light, such as that engaged with the image sensor via the optical component.

[0062] The term "image sensor" refers to one or more components configured to generate an image represented by a data object based on light incident on the image sensor. In some such exemplary contexts, the image sensor converts light waves interacting with the image sensor into signals representing an image output by the sensor.

[0063] The term "near field image sensor" refers to an image sensor configured to capture an image of a near field of view. In at least one context, the near field image sensor includes at least one near field optical component that defines the near field of view, and an electronic sensor. In at least one exemplary context, the near field image sensor may include a global shutter. In some exemplary contexts, the near field image sensor may include a rolling shutter. The term "near field image" refers to electronic data generated by the near field image sensor, the electronic data embodying a captured representation of the near field of view.

[0064] The term "far field image sensor" refers to an image sensor configured to capture an image of a far field of view. In at least one context, the far field image sensor includes at least one far field optical component defining the far field of view, and an electronic sensor. In at least one exemplary context, the far field image sensor may include a rolling shutter. In some exemplary contexts, the far field image sensor may include a global shutter. The term "far field image" refers to electronic data generated by the far field image sensor, the electronic data embodying a captured representation of the far field of view.

[0065] The term "exposure period" refers to electronic data representing the length of time that an image sensor is configured to be exposed to oncoming light. In at least one exemplary embodiment, the image sensor of the imager is configured to utilize a variable exposure time that can be set to a specific exposure time value.

[0066] The term "start time period of the exposure period" refers to a time period of a threshold duration starting from the start of the exposure period. The threshold duration may have a configurable value. In one example, the threshold duration may be zero, and thus, the terms start time period of the exposure period and the start of the exposure period may refer to the same time instance.

[0067] The term "end time period of the exposure period" refers to a time period of a threshold duration that ends at the end of the exposure period, where the threshold duration may have a configurable value. In one example, the threshold duration may be zero, and thus, the terms end time period of the exposure period and the end of the exposure period may refer to the same instance in time.

[0068] Figure 1A 1 is a block diagram of an exemplary multi-sensor imaging system 10 (hereinafter, also referred to as imaging system 10) according to an exemplary embodiment of the present disclosure. The multi-sensor imaging system 10 includes an imaging engine 100 communicatively coupled to a controller 20, a communication interface 40, an activation component 60, and one or more peripheral components 80. In some exemplary embodiments, the imaging system 10 may include a plurality of Figure 1A The imaging system 10 may include fewer or more components as shown. The imaging system 10 is configured to capture one or more images of a target in one or more fields of view using one or more illumination sources. The imaging system 10 processes the one or more images to perform one or more image processing tasks, such as indicia reading. Thus, in some exemplary embodiments of the present disclosure, the imaging system 10 may be partially or fully embodied as a indicia or symbol reader or a handheld device capable of reading indicia and similar symbols. Figure 2 An exemplary embodiment of the imaging system 10 is shown in FIG. 1 , the details of which will be described in subsequent portions of this disclosure.

[0069] The controller 20 may be configured to perform one or more control operations associated with the imaging system 10. For example, the controller 20 may control the imaging engine 100 to cause an image capture of a target in the field of view of the imaging engine 100. Additionally, the controller 20 may process the captured image to perform one or more image processing tasks. The controller 20 may be embodied as a central processing unit (CPU) including one or more processors and a memory. In some exemplary embodiments, the controller 20 may be implemented as one or more of various hardware processing devices using one or more microcontroller units (MCUs), such as a coprocessor, a microprocessor, a digital signal processor (DSP), a processing element with or without an accompanying DSP, or various other processing circuits, including integrated circuits, such as, for example, ASICs (application specific integrated circuits), FPGAs (field programmable gate arrays), hardware accelerators, dedicated computer chips, etc. In some embodiments, the processor of the controller 20 may include one or more processing cores that are configured to operate independently. A multi-core processor may implement multiple processing within a single physical package. Additionally or alternatively, the processor may include one or more processors configured in tandem via the bus to enable independent execution of instructions, pipelining, and / or multithreading.

[0070] The memory may be non-transitory and may include, for example, one or more volatile memories and / or non-volatile memories. For example, the memory may be an electronic storage device (e.g., a computer-readable storage medium) comprising a gate configured to store data (e.g., bits) that can be retrieved by a machine (e.g., a computing device such as a processor). The memory may be configured to store information, data, content, applications, instructions, etc. for enabling the device to perform various functions according to exemplary embodiments of the present invention. For example, the memory may be configured to buffer data for processing by the processor. Additionally or alternatively, the memory may be configured to store instructions for execution by the processor.

[0071] The processor (and / or a coprocessor or any other processing circuit that assists the processor or is otherwise associated with the processor) can communicate with the memory via a bus for transferring information between components of the imaging system 10. The processor can be configured to execute instructions stored in the memory or otherwise accessible to the processor. Additionally or alternatively, the processor can be configured to perform hard-coded functions. Therefore, whether configured by hardware methods or software methods, or by a combination of them, the processor can represent an entity (e.g., physically embodied in the form of a circuit) that can perform operations according to an embodiment of the present invention while being configured accordingly. Therefore, for example, when the processor is embodied as an ASIC, FPGA, etc., the processor can be a specially configured hardware for performing the operations described herein. Alternatively, for example, when the processor is embodied as an executor of software instructions, the instructions can specifically configure the processor to perform the algorithms and / or operations described herein when executing the instructions. Among other things, the processor may also include a clock, an arithmetic logic unit (ALU), and logic gates configured to support the operation of the controller 20.

[0072] The communication interface 40 may include an input interface and an output interface for supporting communication to and from the imaging system 10. The communication interface 40 may be any device, such as a device or circuit embodied in hardware or a combination of hardware and software, which is configured to receive and / or transmit data to / from a communication device that communicates with the imaging system 10. In this regard, the communication interface 40 may include, for example, an antenna (or multiple antennas) and support hardware and / or software for implementing communication with a wireless communication network. Additionally or alternatively, the communication interface 40 may include circuits for interacting with the antenna to cause the transmission of signals via the antenna or processing the reception of signals received via the antenna. In some environments, the communication interface 40 may alternatively or additionally support wired communication. Thus, for example, the communication interface 40 may include a communication modem and / or other hardware and / or software for supporting communication via cable, digital subscriber line (DSL), universal serial bus (USB) or other mechanisms.

[0073] The activation component 60 may include hardware, software, firmware, and / or a combination thereof configured to instruct a user to initiate (and / or terminate) a desired function. For example, the activation component 60 may transmit an activation signal to cause the controller 20 to start the operation of the imaging engine 100, such as starting to be illuminated by one or more illumination sources, and / or capturing one or more images by the image sensor. Additionally or alternatively, the activation component 60 may transmit a deactivation signal to the controller 20 to terminate the corresponding function, such as stopping scanning via the image sensor. In some embodiments, the activation component 60 is embodied as one or more buttons, triggers, and / or other physical components disposed in or on the body of the base. For example, in at least one exemplary context, the activation component 60 is embodied as one or more "trigger" components, and when the operator engages these trigger components (e.g., when the operator squeezes the trigger), the trigger component transmits a signal to the controller 20 to initiate the corresponding function. In some such embodiments, when the operator disengages the component (e.g., when the operator releases the trigger), the activation component may transmit a deactivation signal to the controller 20 to stop such function. Alternatively or additionally, in at least some embodiments, the activation component 60 is embodied without any components that are directly engaged by an operator. For example, when the imaging system 10 is embodied as an imaging device, the activation component 60 may be embodied as hardware and / or software, or a combination thereof, for detecting that the imaging device has been raised and / or positioned to a predefined "scanning" position, and / or lowered from that position to trigger deactivation. Alternatively or additionally, the activation component 60 may be embodied as a user interface element of the imaging system 10. In such embodiments, the activation component 60 embodied as a user interface element may be configured to receive input from a user on the user interface, and then transmit a corresponding command to the controller 20.

[0074] The one or more peripheral components 80 include other structural and functional elements of the imaging system 10, such as, for example, a display device, a user interface, a housing, a base, a power supply, etc. One or more of the peripheral components 80 may be controlled by the controller and may operate according to instructions or controls provided by the controller 20.

[0075] Figure 1BAn exemplary multi-sensor imaging engine (hereinafter also referred to as an "imaging engine") according to an exemplary embodiment of the present disclosure is shown. Specifically, as shown in the figure, the exemplary multi-sensor imaging engine is embodied as a multi-sensor imaging engine 100. The multi-sensor imaging engine 100 includes a plurality of image sensors, in particular near-field image sensors and / or far-field image sensors, which are configured to capture image data objects in a near field of view associated with the near-field image sensor and a far field of view associated with the far-field image sensor, respectively. In at least one exemplary context, the multi-sensor imaging engine 100 is configured to capture images for the purpose of tag reading in different ranges, such as a close-range range using a near-field image sensor and a long-range range using a far-field image sensor.

[0076] As shown, the multi-sensor imaging engine 100 includes a near-field image capture optical device 104A. The near-field capture optical device 104A may be embodied as one or more lenses and / or other optical components that are configured to enable light to laterally transmit through and interact with a corresponding image sensor (specifically, the near-field image sensor 102A). In this regard, the near-field image capture optical device 104A may define a specific field of view that can be captured by the near-field image sensor 102A. In some embodiments, the near-field image capture optical device 104A defines a near field of view associated with a first focus range, so that objects located at the first focus range and / or within a determinable offset can be clearly visible in an image captured by the near-field image sensor 102A.

[0077] In addition, as shown, the multi-sensor imaging engine 100 includes a far-field image capture optical device 104B. The far-field image capture optical device 104B may be embodied as one or more lenses and / or other optical components, which are configured to enable light to laterally penetrate and interact with the corresponding image sensor (specifically, the far-field image sensor 102B). In this regard, the far-field image capture optical device 104B may define a second field of view that can be captured by the far-field image sensor 102B. In some embodiments, the far-field image capture optical device 104B defines a far field of view associated with a second focus range, so that objects located at the second focus range and / or within a determinable offset can be clearly visible in the image captured by the far-field image sensor 102B. In some such embodiments, the near field of view is wider than the far field of view, so that the captured data is more representative of the environment within the field of view of the multi-sensor imaging engine 100. The far field of view may be narrower than the near field of view and focus on a farther range to enable objects located at a larger range than those that can be clearly captured in the near field of view to be more clearly captured. The physical layout of the illumination source and image sensor can be changed in different applications.

[0078] In some exemplary embodiments, the near-field imaging sensor 102A may include a global shutter to provide enhanced motion tolerance. The near-field imaging sensor 102A may use a large field of view (FOV), which enables applications such as but not limited to optical character recognition (OCR), image reconstruction, machine learning, etc. In some embodiments, the far-field sensor 102B may include a rolling shutter. The far-field image sensor 102B uses a small FOV to improve the sampling of the far field. Additionally, each of the near-field image sensor 102A and the far-field image sensor 102B may have an associated focusing mechanism. The focusing mechanism may include a focusing scheme that controls the movement of one or more focusing lenses along the optical axis direction of the image sensor (102A or 102B). To this end, in some embodiments, the focusing scheme may include one or more motors, such as stepper motors. The focusing scheme may provide multiple discrete focus positions in each field of view, and the motor may move the focusing optics of a particular image sensor to each discrete focus position in the discrete focus positions to exhibit a focusing mechanism. For example, in some exemplary embodiments, to change the focus of far-field imaging sensor 102B, a corresponding motor may move the associated focusing optics of far-field imaging sensor 102B to three discrete focus positions in the far field. The operation of each focusing mechanism may be controlled by a processing component such as Figure 1A Controlled by controller 20 or processor 202).

[0079] In some embodiments, for example, as shown in the figure, each image sensor (or a subset thereof) is associated with one or more components for generating illumination, which is configured to illuminate the field of view defined by the image sensor. For example, as shown in the figure, the multi-sensor imaging engine 100 further includes a near-field illumination source 106A and a corresponding near-field projection optical device 108A. The near-field illumination source 106A can generate illumination pulses constituting a near-field illumination pulse train. That is, the activation of the near-field illumination source 106A is performed for a certain time period, and then the near-field illumination source 106A remains deactivated for a set time period before the next activation. The near-field illumination source 106A is configured to generate light in the direction of the optical axis of the near-field projection optical device 108A. The light is refracted through the near-field projection optical device 108A to generate near-field illumination, which can be generated as a desired pattern based on the configuration and design of the near-field projection optical device 108A. In this regard, the illumination generated by the light exiting the near-field projection optics 108A may illuminate a particular field of view, such as a near field of view that may be captured by the near-field image sensor 102A. It should be appreciated that in some embodiments, the near-field illuminator 106A and / or the near-field projection optics 108A may be designed such that the near-field illumination specifically illuminates the near field of view and may affect the functionality of the far-field image sensor 102B without adversely affecting the functionality of the near-field image sensor 102A. For example, due at least in part to the close proximity between the components, reflected light may interact with the far-field image sensor 102B and adversely affect an image created via the far-field image sensor 102B. In some exemplary embodiments, the near-field illumination source 106A may generate the near-field illumination based on one or more illumination pulses that constitute a near-field illumination pulse train.

[0080] Similarly, the multi-sensor imaging engine 100 further includes a far-field illumination source 106B and a corresponding far-field projection optical device 108B. The far-field illumination source 106B generates far-field illumination pulses that constitute a far-field illumination pulse train. The far-field illumination source 106B is configured to generate light in the direction of the far-field projection optical device 108B. The light is refracted through the far-field projection optical device 108B to generate far-field illumination, which can be generated as a desired pattern based on the configuration and design of the far-field projection optical device 108B. In this regard, the far-field illumination can illuminate a specific field of view, such as a far field of view that can be captured by the far-field image sensor 102B. It should be understood that the far-field illumination source 106B and / or the far-field projection optical device 108B can be designed so that the far-field illumination specifically illuminates the far field of view without generating reflections sufficient to adversely affect the operation of the near-field image sensor 102A and / or the far-field image sensor 102B.

[0081] Additionally or alternatively, optionally in some embodiments, the multi-sensor imaging engine 100 also includes an aimer illumination source 110. The aimer illumination source 110 is configured to generate light in the direction of the aimer projection optics 112. For example, the aimer illumination source includes one or more laser diodes and / or high-intensity LEDs that are configured to generate sufficiently powerful and / or concentrated light. The light is refracted through the aimer projection optics 112 to generate aimer illumination, which can be generated as a desired pattern based on the configuration and design of the aimer projection optics 112. In one exemplary context, the aimer pattern can be generated as a laser line pattern for purposes such as barcode scanning.

[0082] The multi-sensor imaging engine 100 also includes a protective window 114. The protective window 114 includes one or more optical components configured to enable generated light to exit the engine 100 and to enable incident light to be received through the image capture optics 104A and 104B to interact with the corresponding image sensors 102A and 102B. In some contexts, the protective window 114 reflects at least a portion of the illumination projected by the far-field projection optics 108B and / or the near-field projection optics 108A, and it may interact with the image sensors 102A and / or 102B by leaking light or through the corresponding image capture optics 104A and / or 104B. For example, at least a portion of the near-field illumination may be reflected toward the far-field image sensor 102B, and if the far-field image sensor 102B is triggered when the illumination pulse occurs, at least a portion of the near-field illumination adversely affects the operation of the far-field image sensor. In at least one exemplary context, far-field illuminator source 106B produces concentrated light and / or otherwise sufficiently designed light such that the far-field illumination produced by far-field projection optics 108B is not sufficiently reflected to adversely affect near-field image sensor 102A.

[0083] It should be understood that in other embodiments, the multi-sensor imaging engine may include any number of image capture optics, image sensors, illumination sources, and / or any combination thereof. In this regard, the imaging engine 100 may be expanded to capture any number of fields of view, each of which may be associated with a corresponding illuminator designed to specifically illuminate the corresponding field of view. One or more of the illumination sources may adversely affect the operation of another illuminator. In such cases, when one such illumination source is activated, the adversely affected image sensor may be activated between illumination pulses of the illumination source, as described herein. Such operations may be implemented in any combination of illumination sources and image sensors.

[0084] In some embodiments, the multi-sensor imaging engine 100 includes one or more processing components (e.g., processors and / or other processing circuits) for controlling activation of one or more components of the multi-sensor imaging engine 100. For example, in at least one exemplary embodiment, the multi-sensor imaging engine 100 includes a processor configured to time illumination pulses of the near-field illumination source 106A and / or the far-field illumination source 106B, and / or control exposure of the near-field image sensor 102A and / or the far-field image sensor 102B. In some such contexts, the processor is embodied as any of a myriad of processing circuit implementations, such as an FPGA, an ASIC, a microprocessor, a CPU, and the like. In at least some embodiments, the processor may communicate with one or more memory devices having computer coded instructions that, when executed by the processor, implement such functions. In some embodiments, it should be understood that the processor may include one or more sub-processors, remote processors (e.g., "cloud" processors), and the like, and / or may communicate with one or more additional processors for performing such functions. For example, in at least one embodiment, the processor may communicate with another processor within the imaging device (e.g., relative to a processor in the image sensor). Figure 2 The processor 202) shown and described above can communicate with and / or operate in conjunction with the other processor.

[0085] Figure 2 An exemplary multi-sensor imaging device according to an exemplary embodiment of the present disclosure is shown. Specifically, Figure 2 An exemplary multi-sensor imaging device 200 is shown. As shown, the multi-sensor imaging device 200 includes a device base 210 for housing various components of the device. In this regard, it should be understood that the device base may be embodied in any of a myriad of base designs, using any of a myriad of materials, etc. to suit positioning the various components of the multi-sensor imaging device 200 for operation. In at least one exemplary context, the device base 210 may be embodied as a handheld device base, a wearable base, etc.

[0086] The multi-sensor imaging device 200 includes the Figure 1B The multi-sensor imaging engine 100 described above. The multi-sensor imaging device 200 also includes a processor 202. The processor 202 (and / or any other co-processor and / or processing circuitry assisting the processor 202 and / or otherwise associated with the processor 202) may provide processing functionality to the multi-sensor imaging device 200. In this regard, the processor 202 may be configured as described above. Figure 1A The controller 20 may be embodied in any of the numerous ways discussed above.

[0087] In some exemplary embodiments, the processor 202 is configured to provide functionality for operating one or more components of the multi-sensor imaging device 200. For example, the processor 202 may be configured to activate the far-field illumination source 106B, the near-field illumination source 106A, and / or the aimer illumination source 110. Additionally or alternatively, in some embodiments, the processor 202 is configured to activate the near-field image sensor 102A and / or the far-field image sensor 102B to expose the corresponding image sensor, and / or to read out the captured data to generate an image based on the captured data during the exposure. Additionally or alternatively, in some embodiments, the processor 202 is configured to process the captured image, for example, based on one or more image processing tasks. In one such exemplary context, the processor 202 is configured to perform an attempt to detect and decode visual markers (such as 1D and / or 2D barcodes) from the captured image. In this regard, the processor 202 may be configured to provide such functionality using a visual marker parsing algorithm and / or a visual marker decoding algorithm.

[0088] Additionally or alternatively, optionally in some embodiments, the multi-sensor imaging device 200 further includes an activation component 206. The activation component 206 may be as described with respect to Figure 1A The activation component 60 may be embodied in numerous ways as discussed above.

[0089] Additionally or alternatively, optionally in some embodiments, the imaging device 200 further includes a display 208. The display 208 may be embodied as an LCD, LED, and / or other screen device configured for data provided by one or more components of the device 200. For example, in some embodiments, the display 208 is configured to render a user interface that includes text, images, control elements, and / or other data provided by the processor 202 for rendering. In some embodiments, for example, the display 208 is embodied as an LCD and / or LED monitor that is integrated with the surface of the device base 210 and visible to the operator, for example to provide information decoded from a barcode and / or information associated with such information decoded from a barcode. In one or more embodiments, the display 208 may be configured to receive user engagement, and / or may transmit one or more corresponding signals to the processor 202 based on the user engagement to trigger a function. In some such embodiments, the display 208 provides user interface functionality that embodies the activation component 206, for example to enable the operator to initiate and / or terminate a scanning function via interaction with the user interface.

[0090] Additionally or alternatively, optionally in some embodiments, the dual imaging device 200 also includes a memory 204. The memory 204 may provide storage functionality, for example to store data processed by the multi-sensor imaging device 200 and / or instructions for providing the functionality described herein. In some embodiments, the processor 202 may communicate with the memory 204 via a bus to transfer information between components of the device and / or retrieve instructions for execution. The memory 204 may refer to Figure 1A The memory 204 may be embodied in numerous ways discussed above with respect to the controller 20 of the embodiment. The memory 204 may be configured to store information, data, content, applications, instructions, etc. for enabling the imaging device 200 to perform various functions according to some exemplary embodiments. In some embodiments, the memory 204 includes computer-coded instructions for execution by the processor 202, for example to perform the functions described herein and / or in conjunction with hard-coded functions executed via the processor 202. For example, when the processor 202 is embodied as an executor of software instructions, these instructions may specifically configure the processor 202 to perform the algorithms and / or operations described herein when executing these instructions. Non-limiting exemplary implementations of the multi-sensor imaging engine 100 and the multi-sensor imaging device 200 are described in U.S. patent application Ser. No. 16 / 684,124, filed on Nov. 14, 2019, entitled “INTEGRATED ILLUMINATION-AIMER IMAGING APPARATUSES”, the contents of which are incorporated herein by reference in their entirety. It should be understood that one or more of such components may be configured to provide illumination synchronization, as described herein.

[0091] In some exemplary embodiments of the present disclosure, the processor 202 and the memory 204 may be embodied together as an imaging control device or a lighting control device, and thus may be fixedly or detachably coupled to the imaging device 200, or may be partially or completely located outside the imaging device 200. In some embodiments, the imaging control device may be embodied as an integrated circuit operatively coupled to the imaging device 200.

[0092] Figure 3 1 shows a visualization of a field of view that may be captured by an exemplary multi-sensor imaging device. Figure 3 , there is shown a near field of view 302 and a far field of view 304 that can be captured by the multi-sensor imaging device 200. As shown, the near field of view 302 is wider than the far field of view, so that more of the environment can be captured within the near field of view 302 than the far field of view 304.

[0093] Furthermore, as shown, the far field of view 304 extends further than the near field of view 302. In this regard, the narrow nature of the far field of view 304 can enable a more detailed representation of a particular portion of an environment to be captured as compared to the near field of view 302. In some embodiments, a corresponding near-field image sensor and a corresponding far-field image sensor of the multi-sensor imaging device 200 can capture the near field of view 302 and the far field of view 304. The near field of view 302 can be associated with a near focus range at a particular distance from a corresponding image sensor in the multi-sensor imaging device 200. Additionally or alternatively, the far field of view 304 can be associated with a far focus range at another distance from a corresponding image sensor in the multi-sensor imaging device 200. In this regard, the near-field focus range can be closer than the far-field focus range, such that objects farther away from the multi-sensor imaging device 200 than from the near-field image sensor have better focus when captured via the far-field image sensor, thereby allowing for an extended range.

[0094] The multi-sensor imaging device 200 may be configured to provide illumination specifically for illuminating each of the fields of view 302 and 304. In this regard, the illumination source may be specifically designed to match the field of view of the corresponding image sensor such that the illumination appropriately illuminates the corresponding field of view without overflow or underillumination. Producing illumination during an illumination period using another illumination source and capturing during a non-corresponding image sensor may result in overflow (e.g., when capturing using a far-field image sensor during a near-field illumination pulse) and / or underillumination (e.g., when capturing using a near-field image sensor during a far-field illumination pulse), which may affect the quality of data in the captured image, such as due to overillumination and / or underillumination, as described. For example, Figure 4 A visualization of near-field illumination generated by a multi-sensor imaging device, such as the multi-sensor imaging device 200, is shown in accordance with an exemplary embodiment of the present disclosure. In this regard, the near-field illumination 402 may be generated so as to substantially or completely illuminate the near field of view 302. The near-field illumination 402 may be generated according to an illumination pattern that sufficiently illuminates the entire near field of view 302 for capture.

[0095] Figure 5A visualization of far-field illumination generated by an exemplary multi-sensor imaging device (e.g., multi-sensor imaging device 200) according to an exemplary embodiment of the present disclosure is shown. In this regard, far-field illumination 404 may be generated so as to substantially or completely illuminate the far field of view 304. Far-field illumination 504 may be generated according to an illumination pattern that sufficiently illuminates the entire far field of view 304 for capture by a corresponding far-field image sensor. Far-field illumination 504 may illuminate only a certain percentage of the near field of view 302, such as a central percentage of the near field of view 302 (e.g., 25%, 50%, etc.). In this regard, activating far-field illumination may be problematic for capturing sufficient images of certain visual markers, such as those extending beyond the boundaries of the far field of view 304 at a particular distance. Therefore, it is desirable to utilize an appropriate illuminator for each image sensor while minimizing flicker and minimizing operating time to increase the likelihood and efficiency of successful visual marker detection and decoding.

[0096] Figure 6 A timing diagram 600 associated with the operational functionality of an exemplary multi-sensor imaging system is shown in accordance with an exemplary embodiment. The timing diagram 600 illustrates the activation and deactivation timing of various components of the multi-sensor imaging device 200 (e.g., but not limited to, near-field illumination source, near-field image sensor, far-field illumination source, far-field image sensor, focus mechanism). Figure 6 The pulses in the timing diagram 600 of the imaging system 10 / imaging device 200 are used to illustrate several separate processes associated with the imaging system 10 / imaging device 200. The vertical extension of the pulses in the timing diagram does not necessarily specify the amplitude of the pulse. According to some exemplary embodiments, each pulse in the timing diagram 600 may be defined by the length of the active time of the associated component / process, followed by the length of the inactive time of the associated component / process. Each pulse may have a corresponding period, which may be defined as the duration during which the amplitude of the pulse remains non-zero. The period of the pulse may start at the start time instance (pulse start time) and end at the end time instance (pulse end time). As used herein, the start time period of the period of the term pulse may refer to a time period of a threshold duration starting from the pulse start time, wherein the threshold duration may have a configurable value. In one example, the threshold duration may be zero, and therefore, the start time period of the period and the pulse start time may refer to the same time instance. Similarly, the end time period of the period of the term pulse may refer to a time period of a threshold duration ending at the pulse end time, wherein the threshold duration may have a configurable value. In at least one exemplary context, the threshold duration may be zero, and thus, the end time of the cycle and the pulse end time may refer to the same time instance. In some exemplary embodiments, the corresponding threshold duration may be configured according to one or more performance parameters of the controller 20 and / or the imaging engine 100.

[0097] As shown in timing diagram 600, some pulses associated with a particular operation of a particular component of imaging system 10 / imaging device 200 may be aligned in time, partially or completely overlapped, or may not overlap with one or more other pulses associated with one or more operations of another component of imaging system 10 / imaging device 200. For example, the start of near-field illumination pulse 602A and the start of pulse 604 associated with exposure of a near-field image sensor (also referred to as near-field exposure pulse 604) are aligned in time. For another example, near-field illumination pulse 602A may not overlap with pulse 606 associated with readout of a near-field image sensor (also referred to as near-field readout pulse 606). For another example, pulse 614A associated with exposure of a far-field image sensor (also referred to as far-field exposure pulse 614A) overlaps with near-field readout pulse 606.

[0098] The imaging system / imaging device may utilize executable instructions corresponding to the operations shown in the timing diagram 600 to perform smooth execution of one or more imaging or image processing tasks. For example, each image sensor activation may include two steps to capture the corresponding image: exposing the image sensor, and reading out from the image sensor. In this regard, it should be understood that the processor 202 may be configured to enable activation of various components based on the timing diagram, for example. According to some exemplary embodiments, the image sensors (102A, 102B) may be operated in a certain manner so that the exposure period of the far-field image sensor 102B is adjusted or adapted to the illumination pulse train of the near-field illumination source 106A. Such modification of the illumination pulse train of the near-field illumination source 106A to accommodate the exposure period of the far-field image sensor 102B may be accomplished in various ways, some examples of which will be referred to. Figures 8 to 10 Have a discussion.

[0099] As shown, the timing diagram 600 includes a near-field illumination pulse train 602 used by the near-field illumination source 106A to generate near-field illumination. The near-field illumination pulse train 602 includes a plurality of illumination pulses, such as illumination pulses 602A, 602B, 602C, 602D, and 602E. It should be noted that in an unmodified form, the near-field illumination pulses may only include illumination pulses similar to the illumination pulse 602A generated at a certain fixed frequency. The controller 20 or processor 202 may add illumination pulses similar to the additional illumination pulses 602B to 602E to adapt the exposure pulse 614 of the far-field image sensor 102B to the near-field illumination pulse train 602, thereby alleviating illumination issues associated with the multi-sensor imaging device 200 / system 10. In this regard, each near-field illumination pulse may be defined by a length of active time (e.g., near-field illumination source 106A on time) followed by a length of inactive time (e.g., near-field illumination source 106A off time). In an exemplary context, the multi-sensor imaging device 200 may be configured to periodically generate near-field illumination pulses 602A with an on-time of 1.5 milliseconds ("ms"), followed by an off-time of 14.5 ms. In this regard, each illumination pulse 602A may begin, last for 1.5 ms, then end, and then another illumination pulse 602A begins after 14.5 ms has elapsed. To avoid obscuration, only one illumination pulse 602A is shown in the near-field illumination pulse train 602. However, it is contemplated that the near-field illumination pulse train 602 in its unmodified form includes a plurality of such illumination pulses 602A in accordance with the exemplary embodiments described herein. The near-field illumination source 106A may generate additional illumination pulses 602B to 602E in a similar manner as described above with the same or different on-times and off-times. Each of the illumination pulses 602A to 602E may extend a duration in the time domain referred to as an illumination period. In the exemplary embodiments described above, for example, each illumination pulse 602A may have an illumination period equal to 1.5 milliseconds. The illumination period of the illumination pulse may start at a first time instance and end at a second time instance. Thus, the first time instance may correspond to an illumination pulse start time of the illumination pulse and the second time instance may correspond to an illumination pulse end time of the illumination pulse.

[0100] In some exemplary embodiments, when near-field illumination is generated, both the near-field image sensor 102A and the far-field image sensor 102B may be activated. As shown, the exposure pulse 604 of the near-field image sensor may be completely or substantially aligned with the near-field illumination pulse 602A of the near-field illumination pulse train 602. That is, the exposure of the near-field image sensor during the exposure pulse 604 may start simultaneously with the start time period of the near-field illumination pulse 602A of the near-field illumination pulse train 602. In some exemplary embodiments, the end time period of the near-field exposure pulse 604 may extend beyond the end time period of the near-field illumination pulse 602A of the near-field illumination pulse train 602. For example, as shown, the near-field image sensor exposure starts at the rising edge of the exposure pulse 604, which is aligned with the rising edge of the first near-field illumination pulse 602A. The exposure of the near-field image sensor 102A ends at a time instance beyond the falling edge of the first near-field illumination pulse 602A. In this regard, near-field image sensor 102A is exposed during the entire (or nearly the entire) first near-field illumination pulse 602A to maximize the likelihood of capturing sufficient data to successfully complete an image processing task, such as barcode scanning.

[0101] It should be understood that in some embodiments, when it is desired to expose the image sensor during an illumination pulse, the illumination pulse may occur at any point during the exposure of the image sensor. For example, where the near-field image sensor 102A is to be exposed during a near-field illumination pulse, the exposure may begin before the illumination pulse, or the illumination pulse may occur at a later time during the exposure. As one such example, in the context of near-field image sensor 102A being associated with a 4.5 ms exposure time value and each near-field illumination pulse lasting 1.5 ms, the exposure of the near-field image sensor 102A may begin at any time between the start of the illumination pulse and 3 ms before the illumination pulse start time, such that the entire illumination pulse occurs during the exposure. It should be understood that the specific timing may be different for any combination of differently configured image sensors and / or illumination sources.

[0102] As shown, near field image sensor 102A is then read out in pulse 606 to generate and / or process a corresponding image (e.g., a first near field image) in pulse 608. In parallel with the start of readout from near field image sensor 102A in pulse 606, exposure of far field sensor 102B may begin in pulse 614. Then, as exposure of far field sensor 102B in far field exposure pulse 614 ends, readout from the far field sensor may begin in pulse 616 to generate and / or process a corresponding image (e.g., a first far field image) in pulse 618.

[0103] It should be noted that in some exemplary embodiments, the start time period of the exposure period of far-field exposure pulse 614 can be completely or substantially aligned with the start time period of the readout period of pulse 606. In addition, the end time period of the exposure period of far-field exposure pulse 614 can be completely or substantially aligned with the start time period of the readout period of pulse 616.

[0104] The timing of the illumination pulses, corresponding exposures, readouts, and / or processing may be determined in any of a myriad of ways. For example, in at least one exemplary embodiment, the timing for activating the illumination pulses and / or exposure of the image sensor may be predetermined and / or hard-coded for execution by one or more associated processors. Additionally or alternatively, in some embodiments, a timing offset until the next illumination pulse may be determined based on the pulse frequency of the illumination generated and / or the start time of the illumination pulse (e.g., the time at which the first illumination pulse is generated). The exposure of one or more image sensors may be appropriately timed based on a known and / or determinable current time, illumination pulse frequency, a determined offset, and / or an exposure time value of the image sensor to be exposed. For example, based on such data, exposure of the image sensor may be triggered such that the image sensor remains exposed for the entire illumination pulse in some cases, and / or remains exposed for all or part of the time between illumination pulses in other cases.

[0105] Each illumination source is used to illuminate a desired field of view for capture by a corresponding image sensor, thereby increasing the likelihood of successfully completing an image processing task such as barcode scanning.

[0106] Figure 7 A flowchart depicting exemplary operations of a process 700 for lighting control in a multi-imager environment is shown in accordance with an exemplary embodiment of the present disclosure. Figure 6 The timing diagram 600 is shown to describe Figure 7 The process 700 may be referred to as Figure 1A and Figure 2 The process 700 includes, at 702, operating, by the controller 20 / processor 202, a first illumination source based on a first illumination pulse train. The first illumination source may correspond to a light source associated with a near-field sensor. For example, the first illumination source may be a reference Figure 1B to Figure 2 The first illumination source may illuminate the near field of view of the near field image sensor according to a first illumination pulse train. The first illumination pulse train may correspond to Figure 6602. In some exemplary embodiments, the first illumination pulse train may have a constant pulse frequency of about 60 to 90 Hz to generate short, bright illumination pulses. In some sensitive applications, the pulse frequency may be set to a constant value exceeding 90 Hz.

[0107] The process 700 also includes, at 704, determining, by the controller 20 / processor 202, a first exposure period for the second image sensor. In some exemplary embodiments, the second image sensor may be a far-field image sensor 102B, and therefore, the first exposure period may correspond to an exposure period of the far-field sensor 102B. The illumination and exposure of the second image sensor may be controlled or caused by a control or processing medium such as the controller 20 or the processor 202. Therefore, the first exposure period of the second image sensor may be predetermined and / or hard-coded for execution by one or more associated processors. In some exemplary embodiments, the exposure period may be dynamically calculated based on one or more imaging parameters associated with the second image sensor.

[0108] Process 700 also includes, at 706, modifying, by the controller 20 / processor 202, one or more characteristics of the first illumination pulse train to accommodate the first exposure period of the second image sensor. By modifying the one or more characteristics, such as the pulse frequency of the first illumination pulse train, process 700 provides an effective measure for suppressing "illumination spillover" from the far-field image sensor into the near-field image sensor (and vice versa). Modifying the one or more characteristics of the first illumination pulse train may be performed with the purpose of reducing illumination interference between image sensors of the imaging system. Thus, the one or more characteristics of the first illumination pulse train may be modified in a myriad of ways. In some exemplary embodiments, one or more additional illumination pulses may be added or inserted into the first illumination pulse train to avoid illumination interference with the exposure of the second image sensor, as described in detail with reference to each. Figure 8 and Fig. 9 Additionally or alternatively, in some exemplary embodiments, a timing delay between a pair of temporally subsequent illumination pulses of the first illumination pulse train may be increased to avoid illumination interference with the exposure of the second image sensor, which has been described in detail with reference to Fig.10 The process 706C is provided.

[0109] Process 700 includes, at 708, operating, by controller 20 / processor 202, a first illumination source associated with a first image sensor based on the modified first illumination pulse train. Thus, controller 20 / processor 202 controls subsequent activation of the near-field illumination source based on the modified near-field illumination pulse train. Exposure of the near-field image sensor is accordingly aligned with the illumination pulses of the modified near-field illumination pulse train to perform image capture by the near-field image sensor. Since the modified near-field illumination pulse train is generated with consideration of the exposure cycle of the far-field image sensor, the possibility of illumination spillover between the two sensors is reduced or, in some cases, eliminated. Thus, process 700 provides an efficient means of operating a multi-sensor imaging system / device. Thus, a device performing or utilizing process 700 produces improvements in imaging and / or subsequent image processing tasks.

[0110] Figure 8 A flow chart depicting exemplary operations of a process 706A for modifying one or more characteristics of a first illumination pulse train to accommodate a first exposure period of a second image sensor of an exemplary multi-sensor imaging system is shown in accordance with at least one exemplary embodiment of the present disclosure. In some exemplary embodiments, process 706A may be triggered in a scene where illumination synchronization and flicker control or elimination are desired.

[0111] Process 706A includes, at 802, determining, by the controller 20 / processor 202, a start time period and an end time period of a first exposure period of a second image sensor. As previously described, the second image sensor may be the far-field image sensor 102B. Thus, the controller 20 / processor 202 may determine the limits of the exposure period of the far-field image sensor. In addition, as described in reference Figure 7 As discussed in step 704 of , the first exposure period of the second image sensor may be predetermined and / or hard-coded for execution by one or more associated processors. In some exemplary embodiments, the exposure period may be dynamically calculated based on one or more imaging parameters associated with the second image sensor. The controller 20 / processor 202 may obtain data related to the exposure period of the far-field image sensor from any of the sources mentioned above and determine the start time period and the end time period of the exposure period.

[0112] At step 804, process 706A includes generating, by controller 20 / processor 202, at least one additional illumination pulse of the first illumination pulse train of the first image sensor. The at least one additional illumination pulse may be generated so as to be inserted into the first illumination pulse train. Thus, process 706A also includes, at 806, inserting, by controller 20 / processor 202, the at least one additional illumination pulse into the first illumination pulse train such that a start time period and / or an end time period of an illumination cycle of the at least one additional illumination pulse is aligned with a start time period and / or an end time period of a first exposure cycle of the second image sensor. That is, the at least one additional illumination pulse may be added or inserted into one or more "random regions" of a pulse corresponding to an exposure cycle of the second image sensor. A "random region" may correspond to such a portion of an exposure cycle in which an object or a portion thereof is not captured. As discussed, the second image sensor may be a far-field image sensor, and in typical scenarios, an initial window and a terminal window associated with a pulse corresponding to an exposure cycle of the far-field image sensor may not be associated with the capture of an object because an object is typically captured within a center window of an exposure cycle of the far-field image sensor. Thus, in the examples shown herein, the initial window and the terminal window of the exposure period may correspond to the arbitrary region. However, it is contemplated that, additionally or alternatively, any other portion of the exposure period may also be defined as an arbitrary region within the scope of the present disclosure.

[0113] like Figure 6 As shown, the one or more additional illumination pulses 602B and 602E (shown in thin dashed lines) are generated and inserted into the near-field illumination pulse train 602 so that the start time period of the illumination cycle of illumination pulse 602B is aligned with the start time period of the exposure pulse 614A of the far-field image sensor, and the start time period of the illumination cycle of illumination pulse 602E is aligned with the start time period of the exposure pulse 614B of the far-field image sensor.

[0114] Fig. 9 Flowchart 706B is shown, which depicts exemplary operations of another process for modifying one or more characteristics of a first illumination pulse train to accommodate a first exposure period of a second image sensor of an exemplary multi-sensor imaging system, in accordance with at least one exemplary embodiment of the present disclosure. In some exemplary embodiments, process 706B may be triggered in a scene where illumination synchronization and flicker elimination are desired.

[0115] Process 706B includes determining, at 902, by the controller 20 / processor 202, an autofocus period for the second image sensor. During operation of the second image sensor for imaging in the far field, the image sensor is required to move to one of several focus positions. The shift from an initial position of the image sensor (and / or associated optics) to one of the focus positions occurs during the autofocus period. The autofocus period may be predefined and stored in a memory of the imaging engine, or may be dynamically calculated based on one or more imaging parameters. In either case, the controller 20 / processor 202 may obtain or otherwise calculate the autofocus period.

[0116] At step 904, process 706B includes generating, by controller 20 / processor 202, at least one additional illumination pulse of the first illumination pulse train for the first image sensor. The at least one additional illumination pulse may be generated so as to be inserted into the first illumination pulse train. Thus, process 706B also includes inserting, by controller 20 / processor 202, at 906, the at least one additional illumination pulse into the first illumination pulse train such that illumination of the first image sensor corresponding to the at least one additional illumination pulse overlaps in time with an autofocus cycle of the second image sensor. That is, the at least one additional illumination pulse may be added or inserted into the first illumination pulse train at a position aligned with a cycle of motor movement of the second image sensor.

[0117] like Figure 6 As shown, the one or more additional illumination pulses 602D (shown in bold dashed lines) are generated and inserted into the near-field illumination pulse train 602 such that an illumination period of the illumination pulse 602D overlaps with the auto-focus motor movement pulse 610 .

[0118] Fig.10 A flow chart is shown that depicts exemplary operations of another process 706C for modifying one or more characteristics of a first illumination pulse train to accommodate a first exposure period of a second image sensor of an exemplary multi-sensor imaging system in accordance with at least one exemplary embodiment of the present disclosure. Process 706C includes, at 1002, determining, by the controller 20 / processor 202, a start time period and an end time period of the first exposure period of the second image sensor. As previously described, the second image sensor may be a far-field image sensor 102B. Thus, the controller 20 / processor 202 may determine the limits (start time period and end time period) of the exposure period of the far-field image sensor. Additionally, as described in reference Figure 7As discussed in step 704 of , the first exposure period of the second image sensor may be predetermined and / or hard-coded for execution by one or more associated processors. In some exemplary embodiments, the exposure period may be dynamically calculated based on one or more imaging parameters associated with the second image sensor. The controller 20 / processor 202 may obtain data related to the exposure period of the far-field image sensor from any of the sources mentioned above and determine the start time period and the end time period of the exposure period.

[0119] Process 706C also includes determining, by controller 20 / processor 202, a pair of temporally subsequent illumination pulses of the first illumination pulse train in the closest temporal vicinity of the first exposure period of the second image sensor at 1004. Controller 20 / processor 202 may determine a start time instance and an end time instance of the exposure period of the far-field image sensor. Controller 20 / processor 202 may map the determined start time instance and end time instance of the exposure period onto the near-field illumination pulse train to determine a pair of temporally subsequent illumination pulses in the near-field illumination pulse train in the closest vicinity of the determined start time instance and end time instance of the exposure period on the time axis, respectively.

[0120] Process 706C also includes, at 1006, increasing, by the controller 20 / processor 202, a timing delay between a pair of eligible temporally subsequent illumination pulses of the first illumination pulse train such that one of the start time period or the end time period of the first exposure period is aligned with a corresponding one of the start time period or the end time period of the increased timing delay. Fig.11 As shown in the exemplary timing diagram 1100 of FIG. 1 , the illumination pulse pairs 1104, 1106 and the illumination pulse pairs 1108, 1110 of the near-field illumination pulse train may be selected as a pair of qualifying illumination pulses that are in the closest proximity of the start time instance and the end time instance of the exposure period 1112. Therefore, the controller 20 / processor 202 may increase the timing delay between the illumination pulses (1102 to 1110) so that the start time period and / or the end time period of the exposure period 1112 are aligned with the corresponding one of the falling edge of the illumination pulse 1104 and the rising edge of the illumination pulse 1106, respectively. The falling edge of the illumination pulse 1104 may be within a threshold delay from the start time period of the exposure period 1112, and the rising edge of the illumination pulse 1106 may be within another threshold delay from the end time period of the exposure period 1112. Similar modifications may be made to the other pulses of the exposure period to align with a pair of corresponding illumination pulses. The duration between the rising edge of illumination pulse 1104 and the falling edge of illumination pulse 1106 defines the incremental timing delay. Fig.11As shown in the modified near-field illumination pulse train, the start time period and the end time period of the exposure period 1112 of the far-field image sensor are aligned with a corresponding one of the start time period or the end time period of the increased timing delay.

[0121] Fig. 12A and Fig. 12B An exemplary workflow of a symbol decoding process performed by an exemplary multi-sensor imaging system according to at least one exemplary embodiment of the present disclosure is shown. In some exemplary embodiments, the imaging system 10 and / or the imaging device 200 may include or be part of an exemplary symbol reading device (such as a badge reader). Fig. 12A , Fig. 12B and Fig. 12C The illustrated processes 1200A, 1200B, and 1200C provide a symbol decoding method that includes aspects of method 700. When implementing processes 1200A, 1200B, and 1200C, a symbol reader having multiple image sensors can mitigate problems caused by illumination spillover and flicker, and can therefore provide error-free or error-reduced symbol image capture. This results in faster and efficient decoding of symbols. Additional advantages of the workflow will become apparent through the following disclosure of the workflow.

[0122] Some or all of the steps of processes 1200A, 1200B, and 1200C may be performed by appropriate data processing devices and control devices. For example, in some exemplary embodiments, processes 1200A, 1200B, and 1200C may be performed by a controller or one or more processors of a symbol reader. In some exemplary embodiments, the controller of the symbol reader may be embodied in a manner similar to that described with reference to controller 20 of imaging system 10.

[0123] The process 1200A is triggered upon receiving input from a user to the activation component 206 of the imaging device 200. In response, the process 1200A begins at 1202 by opening a sight as an indicator. Figure 2 As described, the aimer illumination source 110 and the aimer projection optics 112 can together produce the aimer as a desired pattern. Next, at 1204, the process 1200A includes turning on near-field illumination. The near-field illumination can be generated in a variety of ways, such as previously discussed in this disclosure. In some exemplary embodiments, the near-field illumination is generated according to a near-field illumination pulse train having a fixed pulse frequency. Individual near-field illumination pulses can have a short duration, such as 1.5 ms.

[0124] Exposure of the near-field image sensor begins at 1206 substantially simultaneously with activation of the near-field illumination source. In some exemplary embodiments, the near-field image sensor may include a global shutter and may have a large field of view. In some exemplary embodiments, the near-field image sensor may include a rolling shutter. Subsequently, at 1208, process 1200A may include transmitting data from the near-field image sensor to capture a first near-field image. That is, the charge may be read out to construct an image frame captured by the near-field image sensor.

[0125] In parallel with step 1208, at 1210, process 1200A includes starting exposure of a far field image sensor in the far field. In some exemplary embodiments, the far field image sensor may include a rolling shutter and may have a narrower field of view than the near field image sensor. After the exposure period of the far field image sensor has elapsed, data transmission from the far field image sensor may be started at 1212 to capture a first far field image.

[0126] At 1214, upon capturing the first near-field image, the process 1200A includes processing the first near-field image and starting a first decoding run. The first near-field image is processed to obtain a distance estimate for a target symbol in the image. To this end, any suitable image processing-based distance estimation technique may be utilized (e.g., but not limited to, using a parallax-based technique or a difference in sharpness of images from a near-field image sensor and a far-field image sensor). For example, as a binary test, a determination may be made based on the decoding result of the first decoding run whether the target symbol was successfully captured in the first near-field image. The result of the distance estimation may be used to decide whether the first far-field image will be used to decode the symbol in place of the first near-field image. In an exemplary scenario where the target symbol is outside the maximum imaging range of the near-field image sensor, the captured first near-field image frame may not indicate the target symbol with acceptable clarity, brightness, contrast level, etc. Therefore, near-field imaging may not be an appropriate means for decoding the symbol. In such cases, a far-field image sensor may be relied upon to attempt a successful decoding.

[0127] Process 1200A includes, at 1216, determining whether the symbol was successfully decoded in a first decoding run. If the symbol was successfully decoded from the first near-field image, processing of the first far-field image may not be required and control of the step passes to step 1246 of FIG. 1200C, at which the decoded symbol may be output by the symbol decoder. However, if the symbol decoder did not successfully decode the symbol at 1214, then process 1200A includes, at 1218, moving the imaging engine, and thereby the far-field image sensor, to a corresponding focus position. Movement to the corresponding focus position includes determining a particular focus position by a set of focus points based on the distance estimated in step 1214. The focus positions of the image sensor may be discretely defined as discrete steps to be traversed by a focus motor of the imaging engine. Following movement of the imaging engine at 1218, control of the step passes to Fig. 12B The two parallel processes are shown in process 1200B.

[0128] Process 1200B includes a first flow including steps 1220 to 1232 directed to processing and imaging using a far-field image sensor, and a second flow including steps 1234 to 1242 directed to imaging using a near-field image sensor. In some exemplary embodiments, the second flow including steps 1234 to 1242 may be skipped in one or more iterations of processes 1200A, 1200B, and 1200C.

[0129] Process 1200B includes, at 1220, processing a far field image (in this case, a first far field image) and starting a second decoding run. The first far field image may be processed to decode the target symbol and other parameters of the image may be obtained by the processing. The other parameters may be, for example, the brightness of the first far field image. Using these parameters, one or more sensor parameters of the far field image sensor to be adjusted may be determined. Subsequently, at 1222, it is determined whether the symbol is successfully decoded in the second decoding run. If the result of the check at 1222 is positive (yes), then control of the step is transferred to step 1246 of Figure 1200C, where the decoded symbol may be output by the symbol decoder. However, if the symbol decoder does not successfully decode the symbol at 1222, then control of the step is transferred to 1224, where it is determined whether illumination in the far field is required. Such a determination may be made, for example, on the first far field image by any suitable image processing technique. If it is determined that far field illumination is required, then the far field illumination source may be turned on at 1226 and control may be transferred to step 1228. However, if far field illumination is not required, control may pass directly to step 1228. At 1228, exposure of the far field sensor begins with or without illumination in the far field, as the case may be. Subsequently, data transmission from the far field image sensor may be completed at 1230 to obtain a second far field image. The second far field image may be processed at 1232 and a third decoding run attempted. Next, control passes to Fig. 12C Step 1244 of process 1200C is shown.

[0130] In a parallel second flow of process 1200B, when it is determined that the symbol decoder cannot successfully decode the symbol, the near-field illumination pulse is modified at 1234 to accommodate one or more exposure cycles of the far-field image sensor. Figures 8 to 10 The modification of the near-field illumination pulses may be accomplished by modifying the near-field illumination pulse train in the numerous ways discussed. Subsequently, at 1236, near-field illumination may be initiated in accordance with the modified near-field illumination pulses, and at 1238, the near-field image sensor may be exposed in the near field. The illumination and exposure of the near-field image sensor after the illumination pulse modification may be accomplished in a manner similar to that described at steps 1204 and 1206, respectively. At 1240, process 1200B includes initiating data transmission of the near-field image sensor to capture a second near-field image. At 1242, the second near-field image may be processed, and the symbol decoder may attempt a fourth decoding run. Next, control passes to Fig. 12C Step 1244 of process 1200C is shown.

[0131] At 1244, it is determined whether the symbol is decoded in any of the third decoding run 1232 or the fourth decoding run 1242. If the symbol decoder is able to successfully decode the target symbol from any of the second far-field image or the second near-field image, control of the step is transferred to 1246, where the decoded symbol is output by the symbol decoder. However, if it is determined at 1244 that the symbol decoder did not successfully decode the symbol, control is transferred to 1248, where it is determined whether there are still any focus positions that have not been visited. That is, the process 1200C includes determining whether there are any focus positions from which imaging in the far field has not been performed in any iteration among the focus positions of the far-field image sensor. If there are still no such focus positions from which imaging in the far field has not been performed (i.e., all focus positions have been visited), it is inferred that the target symbol is outside the imaging range of the symbol decoder or there is no target symbol in the imaged field of view. Therefore, at 1250, an error message indicating that the target symbol cannot be decoded by the symbol decoder can be output. However, if it is determined at 1248 that there are still one or more focus positions that have not been visited, control passes to 1252 where the imaging engine moves in the far field to the corresponding position that has not been visited. Fig. 12B The movement of the imaging engine is performed in a manner similar to that described in step 1218 of process 1200B. The movement to the focus position may be arranged in ascending order (i.e., moving from a closer focus position to a farther focus position among the discrete focus positions of the far-field image sensor). Control then returns to the two parallel flows at steps 1220 and 1234 of process 1200B.

[0132] In this way, FIG. 12A to FIG. 12C The exemplary workflow shown can be used to perform symbol decoding by a symbol decoder, whereby the likelihood of successfully decoding target symbols from near-field images and far-field images is significantly increased due to the improved illumination control provided by the modification of the near-field illumination pulses (pulse trains). Such improvements in the decoding process bring about improvements in the overall functionality of the symbol decoder device itself.

[0133] Although the terminal application as symbol decoding has been described FIG. 12A to FIG. 12CThe exemplary workflow shown, but it is expected that within the scope of the present disclosure, other terminal application tasks utilizing dual or multiple image sensors (and thus multiple illumination sources) can also be modified to benefit from the improved illumination control and synchronization framework provided herein. That is, the scope of the present disclosure should never be limited to a single symbol decoder, and suitable modifications can be made to extend the illumination control framework to similar terminal use cases, such as mobile phones based on multiple cameras. In some exemplary contexts, a multi-image sensor device can be embodied as a smartphone with at least two cameras. The camera can have the same or separate illumination sources associated with each of them. At least one camera in a smartphone can be considered a main camera, which is associated with image capture in bright, well-lit and poorly lit situations. The image quality of such a camera can be directly associated with megapixel (MP) intensity, and so in some exemplary embodiments, the main camera can have 12, 24, 48 or 64MP. One or more other cameras in a smartphone can be considered as auxiliary cameras associated with one or more image enhancement functions. For example, a smartphone can have a telephoto lens that supports a super zoom option. In some exemplary embodiments, the telephoto lens can support a zoom factor between 2x and 10x. In some more advanced embodiments, the smartphone may have an ultra-wide angle lens for enhancing the field of view of the smartphone. Additionally or optionally, in some exemplary embodiments, the smartphone may include a depth sensor to measure the depth of background objects compared to the main object in the field of view. One or more cameras of the smartphone may have different lighting requirements to support the general imaging capabilities of the smartphone. For example, while the main camera may require an illumination flash for imaging in a low-light scene, the monochrome lens of the smartphone may experience a spike in brightness during imaging in the same pulse. Therefore, the resulting image may be affected in terms of one or more imaging parameters.

[0134] The exemplary embodiments described herein help alleviate the aforementioned problems by providing an effective solution for synchronizing the illumination of multiple cameras in a smartphone. Figures 6 to 12C As shown, the exposure of one or more cameras can be designed or adjusted to overlap with or be outside the exposure of one or more other cameras as required. Since the exemplary embodiment also provides an adaptive process for illumination synchronization, the proposed solution is applicable to various imaging scenarios and situations.

[0135] In some exemplary embodiments, in a multi-imager environment such as a multi-image sensor device, cycling between illumination sources (e.g., near-field illumination sources and far-field illumination sources) during symbol reading / decoding may cause a flickering effect to an operator of the multi-image sensor device. Therefore, the lighting control framework may also include one or more frameworks for reducing flickering. Fig.13 An exemplary workflow of a generalized flicker reduction process 1300 performed by an exemplary multi-sensor imaging system in accordance with at least one exemplary embodiment of the present disclosure is shown.

[0136] At 1302, process 1300 includes operating a first illumination source associated with a near-field sensor based on a first illumination pulse train. The first illumination source may be a reference Figure 2 Therefore, the near-field illumination pulse train such as Figure 6 The near-field illumination pulse train 602 or Fig.11 The first near-field illumination source may be configured to generate pulsed illumination in the near field of the imaging engine. Each individual pulse may have a short duration, such as 1.5 ms, and may or may not be periodic with other illumination pulses of the pulse train.

[0137] At 1304, process 1300 includes causing exposure of the near-field image sensor during a first exposure period. The start time period of the first exposure period can be substantially or completely aligned with the start time period of the illumination period of the first illumination source. That is, the exposure of the near-field image sensor can begin substantially simultaneously with the activation of the first illumination source, such as Fig.11 The exposure of the near-field image sensor may continue for a period that ends after the illumination period of the first illumination source ends (ie, after the activation period of the first illumination source).

[0138] At 1306, process 1300 includes causing exposure of the far-field sensor during a second exposure period that does not overlap with any illumination period of the first illumination source. For example, the far-field image sensor of imaging device 200 / imaging system 10 may be exposed during the second exposure period. The start time period and the end time period of the second exposure period of the far-field image sensor may be scheduled in a manner such that they do not overlap with illumination periods of any illumination pulses of the near-field illumination pulse train. That is, exposure of the far-field image sensor may occur during the time period when the first illumination source is deactivated.

[0139] In this way, modifying the near-field illumination pulse train to accommodate the far-field exposure period ensures that illumination spillover from the far-field illumination does not occur into the exposure of the near-field image sensor and vice versa. Since the far-field image sensor is exposed only during the deactivation period of the near-field illumination source, there is no interference from the near-field illumination source in the exposure of the far-field image sensor. In addition, this arrangement ensures that these illuminations (near-field illumination and far-field illumination) are generated substantially sequentially (i.e., there is no or very little time gap between the activation of the near-field illumination and the activation of the far-field illumination for consecutive pulses). Therefore, the operator is not able to perceive noticeable flickering caused by dimming and brightening of the illumination source.

[0140] In some exemplary embodiments, the target to be captured may be located at a considerable distance from the imaging engine. Therefore, the capture of the target may be accomplished using a far-field image sensor. In addition, such a scenario may be equivalent to imaging from the farthest focus (shortest focal length) of the far-field image sensor, which requires the longest exposure of the far-field image sensor, for example when the far-field image sensor includes a rolling shutter. In such scenarios, maintaining the activation of the far-field illumination source for a long duration may bring about several problems in the operation of the imaging engine, such as overheating caused by the extended activation of the far-field illumination source. Therefore, for such scenarios, it may be desirable to reduce the framework of the activation time of the far-field illumination source while ensuring that the far-field imaging is not affected. Fig.14 An exemplary workflow of a flicker reduction process 1400 (particularly extended far-field exposure) performed by an exemplary multi-sensor imaging system in accordance with at least one exemplary embodiment of the present disclosure is shown.

[0141] Process 1400 includes, at 1402, operating a first illumination source associated with a near-field sensor based on a first illumination pulse train. Step 1402 may be performed in a similar manner as step 1302.

[0142] Process 1400 includes, at 1402 , causing exposure of the near field sensor during a first exposure period, a start time period of the first exposure period being aligned with a start time period of an illumination period of a first illumination source. Step 1402 may be performed in a similar manner as step 1304 .

[0143] Process 1400 also includes causing exposure of the far-field sensor during a second exposure period at 1406, the second exposure period overlapping at least one illumination period of the first illumination source. For example, the far-field image sensor of imaging device 200 / imaging system 10 may be exposed during the second exposure period. In some exemplary embodiments, a start time period or an end time period of the second exposure period of the far-field image sensor may be scheduled in a manner such that a start time period or an end time period of the second exposure period of the far-field image sensor is completely or substantially aligned with a start time period or an end time period of an illumination period of an illumination pulse of the near-field illumination pulse train. For example, Figure 6 As shown, the start time period of far-field exposure pulse 614A is aligned with illumination pulse 602B of near-field illumination pulse train 602 .

[0144] In an exemplary context where the target to be captured falls in the central region of the field of view of the far-field image sensor, in order to extend the exposure time of the far-field image sensor, the exposure may be modified so that at most only a small number of top and bottom rows of the rolling shutter-based far-field image sensor are exposed when the near-field illumination source is activated. This minimizes reflections and light leakage / illumination spillover to the outer top and bottom regions of the far-field image, thereby ensuring that the minimum size region falling in the central region of the field of view of the far-field sensor in such contexts does not receive illumination from the near-field illumination source, as it would interfere with automatic gain control operation and general decoding. As a result, the resulting captured image is free from any adverse effects that may be caused by illumination spillover from the near-field illumination source.

[0145] It is contemplated that within the scope of the present disclosure, if the target to be captured falls within an area other than the central area of ​​the field of view of the far-field image sensor, the minimum size area may be configurable by an operator / administrator of the imaging engine. That is, the minimum size area may be defined based on the location of the target to be captured in the field of view of the far-field image sensor.

[0146] In this way, Fig.14 Exemplary embodiments of the flicker reduction process provide effective reduction of operator-perceivable flicker by ensuring overlap between the exposure period of the far-field image sensor and the illumination period of the near-field illumination source.

[0147] It should be understood that the above Figure 7 , Figure 8 , Fig. 9 , Fig.10 , Fig. 12A , Fig. 12B , Fig. 12C , Fig.13 and Fig.14Each box in the flowchart shown in and the combination of boxes in the flowchart can be implemented by various devices (such as hardware, firmware, processor, circuit, and / or other communication devices associated with the execution of software including one or more computer program instructions). For example, one or more of the above processes can be embodied by computer program instructions. In this regard, the computer program instructions embodying the above process can be stored by the memory device of the device using the embodiment of the present invention and executed by the processor of the imaging device / system. It should be understood that any such computer program instructions can be loaded onto a computer or other programmable device (e.g., hardware) to produce a machine so that the resulting computer or other programmable device implements the functions specified in the flowchart box. These computer program instructions can also be stored in a computer-readable memory, which can instruct a computer or other programmable device to work in a specific manner so that the instructions stored in the computer-readable memory produce a product, and the execution of these instructions implements the functions specified in the flowchart box. The computer program instructions can also be loaded onto a computer or other programmable device so that a series of operations are performed on the computer or other programmable device, thereby generating a computer-implemented process so that the instructions executed on the computer or other programmable device provide operations for implementing the functions specified in the flowchart box.

[0148] Therefore, the blocks in the flowchart support a combination of means for performing the specified functions and a combination of operations for performing the specified functions / operations. It will also be understood that one or more blocks in the flowchart and a combination of blocks in the flowchart can be implemented by a hardware-based special-purpose computer system that performs the specified functions or a combination of special-purpose hardware and computer instructions.

[0149] Although an exemplary processing system has been described above, specific implementations of the subject matter and functional operations described herein may be implemented in other types of digital electronic circuitry, or in computer software, firmware, or hardware (including the structures disclosed in this specification and their structural equivalents), or in a combination of one or more of them.

[0150] The embodiments of the subject matter and operations described herein may be implemented in digital electronic circuits, or in computer software, firmware or hardware (including the structures disclosed in this specification and their structural equivalents), or in a combination of one or more of them. The embodiments of the subject matter described herein may be implemented as one or more computer programs (i.e., one or more modules of computer program instructions) encoded on a computer storage medium for execution by an information / data processing device or for controlling the operation of an information / data processing device. Alternatively or additionally, program instructions may be encoded on an artificially generated propagation signal (e.g., a machine-generated electrical signal, optical signal, or electromagnetic signal), which is generated to encode information / data for transmission to a suitable receiver device for execution by an information / data processing device. The computer storage medium may be a computer-readable storage device, a computer-readable storage substrate, a random or serial access memory array or device, or a combination of one or more of them, or may be included in a computer-readable storage device, a computer-readable storage substrate, a random or serial access memory array or device, or a combination of one or more of them. Additionally, while a computer storage medium is not a propagated signal, a computer storage medium can be a source or destination of computer program instructions encoded in an artificially generated propagated signal. A computer storage medium can also be, or be included in, one or more separate physical components or media (e.g., multiple CDs, disks, or other storage devices).

[0151] The operations described herein may be implemented as operations performed by an information / data processing apparatus on information / data stored on one or more computer-readable storage devices or received from other sources.

[0152] The term "data processing device" covers all kinds of devices, equipment and machines for processing data, including, for example, a programmable processor, a computer, a system on a chip, or a plurality of the foregoing devices or a combination thereof. The device may include a dedicated logic circuit (e.g., an FPGA (field programmable gate array) or an ASIC (application-specific integrated circuit)). In addition to hardware, the device may also include code that creates an execution environment for the computer program under consideration (e.g., code constituting processor firmware, a protocol stack, a repository management system, an operating system, a cross-platform operating environment, a virtual machine, or a combination of one or more of them). The device and the execution environment may implement various computing model infrastructures, such as web services, distributed computing infrastructures, and grid computing infrastructures.

[0153] A computer program (also referred to as a program, software, software application, script, or code) may be written in any form of programming language, including compiled or interpreted languages, declarative languages, or procedural languages, and may be deployed in any form, including as a stand-alone program or as a module, component, subroutine, object, or other unit suitable for use in a computing environment. A computer program may, but need not, correspond to a file in a file system. A program may be stored in a portion of a file that holds other programs or information / data (e.g., one or more scripts stored in a markup language document), in a single file dedicated to the program in question, or in multiple coordinated files (e.g., files storing portions of one or more modules, subroutines, or code).

[0154] The processes and logic flows described herein can be performed by one or more programmable processors executing one or more computer programs to perform actions by operating on input information / data and generating output. By way of example, processors suitable for executing computer programs include both general-purpose microprocessors and special-purpose microprocessors and any one or more processors of any kind of digital computer. Generally speaking, the processor will receive instructions and information / data from a read-only memory or a random access memory or both. The basic elements of a computer are a processor for performing actions according to instructions and one or more memories for storing instructions and data. Generally speaking, a computer will also include one or more mass storage devices (e.g., disks, magneto-optical disks, or optical disks) for storing data, or be operably coupled to the one or more mass storage devices to receive information / data from the one or more mass storage devices or transfer information / data to the one or more mass storage devices, or both. However, a computer does not need to have such devices. Devices suitable for storing computer program instructions and information / data include all forms of non-volatile memory, media, and storage devices, including by way of example semiconductor memory devices such as EPROM, EEPROM, and flash memory devices; magnetic disks, such as internal hard disks or removable disks; magneto-optical disks; and CD-ROM and DVD-ROM disks. The processor and memory may be supplemented by, or incorporated in, special purpose logic circuitry.

[0155] To provide interaction with a user, embodiments of the subject matter described herein may be implemented on a computer having a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information / data to the user, as well as a keyboard and pointing device (e.g., a mouse or trackball through which the user can provide input to the computer). Other types of devices may also be used to provide interaction with a user; for example, feedback provided to the user may be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user may be received in any form, including sound, voice, or tactile input. In addition, a computer may interact with a user by sending documents to and receiving documents from a device used by the user; for example, by sending a web page to a web browser in response to a request received from a web browser on a user's client device.

[0156] Although this specification includes many specific implementation details, these details should not be interpreted as limiting the scope of any disclosed or claimable content, but should be interpreted as a description of specific features for a specific disclosed specific embodiment. Certain features described herein in the context of a separate embodiment may also be implemented in combination in a single embodiment. On the contrary, the various features described in the context of a single embodiment may also be implemented in multiple embodiments or in any suitable sub-combination. In addition, although features may be described above as acting in certain combinations and even initially claimed, in some cases, one or more features from the claimed combination may be removed from the combination, and the claimed combination may be for a sub-combination or a variation of the sub-combination.

[0157] Similarly, although operations are depicted in a particular order in the accompanying drawings, this should not be understood as requiring that such operations be performed in the particular order shown or in a sequential order, or that all of the illustrated operations be performed to achieve the desired result. In some cases, multitasking and parallel processing may be advantageous. In addition, the separation of various system components in the above-described embodiments should not be understood as requiring such separation in all embodiments, and it should be understood that the described program components and systems can generally be integrated together in a single software product or grouped into multiple software products.

[0158] Thus, specific embodiments of the subject matter have been described. Other embodiments are within the scope of the following claims. In some cases, the actions described in the claims can be performed in a different order and still achieve the desired results. In addition, the processes depicted in the accompanying drawings do not necessarily require the specific order or sequential order shown to achieve the desired results. In some specific implementations, multitasking and parallel processing may be advantageous.

Claims

1. An imaging system, comprising: a first illumination source associated with a first image sensor, wherein the first illumination source is configured to operate based on a first illumination pulse train; a second image sensor; and a controller comprising processing circuitry, the controller being communicatively coupled to the first illumination source, the first image sensor, and the second image sensor, wherein the controller is configured to: determining a first exposure period of the second image sensor; as well as modifying one or more characteristics of the first illumination pulse train to accommodate the first exposure period of the second image sensor, wherein the controller is further configured to insert at least one additional illumination pulse into the first illumination pulse train such that illumination of the first image sensor corresponding to the at least one additional illumination pulse overlaps in time with an autofocus period of the second image sensor.

2. The imaging system of claim 1 , wherein, in order to modify the one or more characteristics of the first illumination pulse train, the controller is further configured to insert at least one additional illumination pulse into the first illumination pulse train such that one of a start time period or an end time period of an illumination period of the at least one additional illumination pulse is aligned with a corresponding one of a start time period or an end time period of the first exposure period of the second image sensor.

3. The imaging system of claim 1 , wherein to modify the one or more characteristics of the first illumination pulse train, the controller is further configured to increase a timing delay between a pair of temporally subsequent illumination pulses of the first illumination pulse train such that one of a start time period or an end time period of the first exposure period is aligned with a corresponding one of a start time period or an end time period of the increased timing delay.

4. The imaging system according to claim 1, wherein the first image sensor is exposed during at least a second exposure period, wherein the exposure of the first image sensor during the second exposure period starts simultaneously with the start time period of the first illumination pulse of the first illumination pulse train, and The end time period of the second exposure period extends beyond the end time period of the first illumination pulse of the first illumination pulse train.

5. The imaging system of claim 1 , wherein the controller is further configured to: obtaining an image frame captured by exposure of the second image sensor during the first exposure period; determining a brightness of the image frame; and A second illumination source associated with the second image sensor is activated based on the determined brightness of the image frame, wherein the second illumination source is configured to operate based on a second illumination pulse train.

6. The imaging system of claim 1, wherein exposure of the first image sensor begins simultaneously with activation of the first illumination source. 7 . The imaging system of claim 6 , wherein the second image sensor remains deactivated during a first illumination period of a first illumination pulse of the first illumination pulse train.

8. The imaging system of claim 6, wherein the second image sensor is exposed during a portion of a second illumination period of a second illumination pulse of the first illumination pulse train.

9. An imaging method, comprising: operating a first illumination source associated with a first image sensor based on a first illumination pulse train; determining a first exposure period of the second image sensor; as well as modifying one or more characteristics of the first illumination pulse train to accommodate the first exposure period of the second image sensor, wherein modifying the one or more characteristics of the first illumination pulse train comprises inserting at least one additional illumination pulse into the first illumination pulse train such that one of a start time period or an end time period of an illumination period of the at least one additional illumination pulse is aligned with a corresponding one of a start time period or an end time period of the first exposure period of the second image sensor, and Wherein, modifying the one or more characteristics of the first illumination pulse train comprises inserting at least one additional illumination pulse into the first illumination pulse train such that illumination of the first image sensor corresponding to the at least one additional illumination pulse overlaps in time with an autofocus period of the second image sensor.

10. The imaging method according to claim 9, further comprising: causing exposure of the first image sensor during at least a second exposure period, wherein the exposure of the first image sensor during the second exposure period starts simultaneously with the start time period of the first illumination pulse of the first illumination pulse train, and The end time period of the second exposure period extends beyond the end time period of the first illumination pulse of the first illumination pulse train.

11. The imaging method according to claim 9, further comprising: obtaining an image frame captured by exposure of the second image sensor during the first exposure period; determining the brightness of the image frame; as well as A second illumination source associated with the second image sensor is activated based on the determined brightness of the image frame, wherein the second illumination source is configured to operate based on a second illumination pulse train.

12. An apparatus comprising: a memory configured to store executable instructions; as well as One or more processors configured to execute the executable instructions to: controlling operation of a first illumination source associated with a first image sensor based on a first illumination pulse train; determining a first exposure period of the second image sensor; and One or more characteristics of the first illumination pulse train are modified to adapt the first exposure period of the second image sensor by inserting at least one additional illumination pulse into the first illumination pulse train, so that the illumination of the first image sensor corresponding to the at least one additional illumination pulse overlaps in time with the autofocus period of the second image sensor.

13. The apparatus of claim 12, wherein the one or more processors are further configured to: obtaining an image frame captured by exposure of the second image sensor during the first exposure period; determining a brightness of the image frame; and A second illumination source associated with the second image sensor is activated based on the determined brightness of the image frame, wherein the second illumination source is configured to operate based on a second illumination pulse train.

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