Image module and reader and method for reading targets by image registration with a substantially co

专利摘要:
Targets are read by image registration with a substantially constant resolution over a wide range of working distances. Reflection light returning from a distant target located at a distant working distance is observed by a matrix of pixels over a relatively narrow field of view, and over a relatively wide field of vision when a nearby target is located at a nearby working distance. A controller processes the observed reflection light from the remote target with only a set of the pixels located in a central portion of the matrix. For the nearby target, the controller groups all pixels into sets, each set containing a multiple of pixels, and processes the observed reflection light from the nearby target of each of the sets.
公开号:BE1025279B1
申请号:E2017/5663
申请日:2017-09-19
公开日:2019-01-07
发明作者:Christopher W. Brock；David T. Shi
申请人:Symbol Technologies Llc；
IPC主号:

专利说明:

BE2017 / 5663
Image module and reader and method for reading targets by image registration with a substantially constant resolution over a wide range of working distances
BACKGROUND OF THE INVENTION
The present description essentially relates to an image module, an image reader, and a method for reading out targets, such as barcode symbols, to read them electro-optically through image recording with a substantially constant resolution over a wide range of working distances from the module / reader.
Semiconductor image systems or image readers have long been used in both hand-held and hands-free operation modes, in many industries such as retail, manufacturing, storage, distribution, mail transport, logistics, etc., for electro-optic reading of targets, such as single-decode or two-dimensional barcode symbols. A known image reader is generally provided with an image module, also known as a scanning motor, which is placed in a housing and which is typically provided with an illumination system for emitting illumination light in the direction of targets for reflection and scattering thereon; and an image system provided with a semiconductor image sensor, also known as an image sensor, with a matrix of light sensors or pixels, and an image lens assembly for capturing reflection light scattered and / or reflected by the exposed targets, and for projecting the captured exposure light onto the image sensor to initiate the capture of an image of each target. The image sensor produces electrical signals that are decoded and / or processed by a programmed microprocessor or controller into information that relates to each read-out target, for example decoded data that identifies each target. The control is operative for transmitting the decoded data, either via a wireless or
BE2017 / 5663 amount connection, to a remote receiver for further processing, for example, retrieving a price from a price database to obtain a price for each identified target.
The known image lens assembly can be a type with a fixed focal length and can comprise a plurality or group of fixed lenses, such as a classic Cooke triplet provided with a center lens between a pair of side people. To depict targets that may be located over a wide range of working distances from the reader, it is known to configure the fixed focal length reader with different lens configurations provided with different focal lengths, each lens configuration being designed to focus at a different working distance to state. However, such multiple lens configurations are expensive and not easily adaptable over a wide range of applications.
The known image lens assembly can also be of a variable focal length type and can include one or more movable lenses, which are moved by, for example, a linear motor, to automatically focus a target between a near or nearby working distance closer to the reader and a remote or remote working distance further away from the reader. However, this mechanical lens movement is disadvantageous for various reasons. First, the mechanical lens movement produces vibrations which, in the case of a palm reader, can continue through the reader in the user's hand, can produce dust covering the lenses, and can produce an unwanted, annoying, audible buzz. Furthermore, the linear motor is very susceptible to hand movement, uses electric current, is expensive and notoriously slow, can be unreliable, takes up space, and increases the entire weight, the entire size and the entire complexity of the reader.
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Another problem associated with the known image readers is related to the resolution or detail in which the image of each target is captured. A distant target located at a distant working distance is best read by the high resolution image sensor over a relatively narrow field of view, because the apparent size of the distant target is relatively small. A nearby target located at a nearby working distance is best read by the image sensor over a relatively wide field of view, because its apparent size is relatively large, and a high resolution is not required for the image sensor due to the proximity of the nearby target. A multimegapixel image sensor could provide the high resolution for the distant target, but such an image sensor is not only expensive, but handling such a large number of pixels reduces the frame rate of the image sensor and also slows down the processing of the electrical signals which must be decoded and processed. Such time delays have a negative influence on the aggressiveness of the reader and cause the performance in many applications to become too slow.
Therefore, it would be desirable to read electro-optically and quickly targets by image registration with a substantially constant resolution over a wide range of working distances.
SUMMARY OF THE INVENTION
According to an aspect of the invention, there is provided an image processing module for electro-optically reading out targets by image recording with a substantially constant resolution over a wide range of working distances from the module, the module comprising an image processing system provided with an image sensor which is provided with a matrix of pixels for observing reflection light coming back over a relatively narrow field of view
BE2017 / 5663 a first target located at a first working distance with respect to the module, and for observing reflection light over a relatively wide field of view that comes back from a second target located at a second working distance with respect to the module, wherein the second working distance is closer to the module than the first working distance; and wherein the module comprises a control operatively connected to the image processing system and operable to process the observed reflection light from the first target by only a set of the pixels located in a central portion of the matrix, and further operable to processing the observed reflection light of the second target by grouping all pixels into sets, wherein each set contains a multiple of pixels, and by processing the observed reflection light of the second target of each of the sets. Moreover, the first target can be cited as the distant target, and the second target can also be cited as the nearby target.
The image processing module can preferably comprise a distance measuring system for determining the working distance to each of the targets to be read.
The pixels may extend along common orthogonal, horizontal, and vertical center lines to sense the reflection light returning from each of the targets along an imaginary center line that is substantially perpendicular to the horizontal and vertical center lines; wherein the pixels may be arranged in a predetermined number of linear rows that are substantially parallel to the horizontal axis, and wherein the pixels may be arranged in a predetermined number of linear columns that are substantially parallel to the vertical axis.
The image processing system may further be provided with an image lens assembly for capturing the reflection light and for
BE2017 / 5663 projecting the captured reflection light onto the image sensor to initiate image capture of the target, and wherein the image lens assembly has a variable focal point over the extended range of working distances.
The set of the pixels located in the central portion of the matrix may consist of a number of rows that is smaller than the aforementioned predetermined number of rows, and a number of columns that is smaller than the aforementioned predetermined number of columns.
Each set can form a single working pixel that is larger than each individual pixel.
The controller can be configured to process the observed reflection light of the second target in a predetermined frame rate, and to process the observed reflection light of the first target in a frame rate that is greater than the predetermined frame rate.
According to a further aspect of the invention, there is provided an image reader for electro-optically reading targets by image registration with a substantially constant resolution over a wide range of working distances from the reader, the reader comprising a housing provided with a translucent window; and comprises an image processing module mounted in the housing, the module being provided with an image processing system provided with an image sensor provided with a matrix of pixels for observing reflection light coming back through the window from a window first target located at a first working distance with respect to the module, and for observing over a relatively wide field of view reflection light coming back from a second target located at a second working distance with respect to the module, the second working distance being closer the module is then the first working distance, and includes a controller operatively connected to it
BE2017 / 5663 image processing system and is effective for processing the observed reflection light of the first target by only a set of the pixels located in a central portion of the matrix, and furthermore is effective for processing the observed reflection light of the second target by grouping all pixels into sets, wherein each set contains a plurality of pixels, and processing the observed reflection light from the second target of each of the sets.
The image reader may further comprise a distance measuring system for determining the working distance to each of the targets to be read.
The pixels may extend along common orthogonal, horizontal, and vertical center lines to sense the reflection light returning from each of the targets along an imaginary center line that is substantially perpendicular to the horizontal and vertical center lines; wherein the pixels may be arranged in a predetermined number of linear rows that are substantially parallel to the horizontal axis, and wherein the pixels may be arranged in a predetermined number of linear columns that are substantially parallel to the vertical axis.
The image processing system may further be provided with an image lens assembly for capturing the reflection light, and for projecting the captured reflection light onto the image sensor to initiate capturing an image of the target, and wherein the image lens assembly has a variable focal point over the extended range of working distances.
The set of the pixels located in the central portion of the matrix may consist of a number of rows that is smaller than the aforementioned predetermined number of rows, and a number of columns that is smaller than the aforementioned predetermined number of columns.
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Each set can form a single working pixel that is larger than each individual pixel.
The controller can process the observed reflection light of the second target in a predetermined frame rate, and process the observed reflection light of the first target in a frame rate that is greater than the predetermined frame rate.
According to yet another aspect of the invention, there is provided a method for electro-optically reading targets by image recording with a substantially constant resolution over a wide range of working distances from a matrix of pixels of an image sensor, the method comprising the observing reflection light from a first target located at a first working distance with respect to the matrix over a relatively narrow field of vision and observing reflection light returning from a second target located at a second target over a relatively wide field of vision working distance with respect to the matrix, the second working distance being closer to the matrix than the first working distance; processing the observed reflection light of the first target by just a set of the pixels located in a central portion of the matrix, and processing the observed reflection light of the second target by grouping all the pixels into sets, each set being a a plurality of pixels, and by processing the observed reflection light of the second target of each of the sets.
The method may further include determining the working distance to each of the targets to be read.
The method may also include configuring the pixels to extend along common orthogonal, horizontal, and vertical center lines to sense the reflection light returning from each of the targets along an imaginary center line
BE2017 / 5663 is substantially perpendicular to the horizontal and vertical center lines; and arranging the pixels into a predetermined number of linear rows that are substantially parallel to the horizontal axis, and into a predetermined number of linear columns that are substantially parallel to the vertical axis.
The method may further include capturing the reflection light, and projecting the captured reflection light onto the matrix to initiate capturing an image of the target, and varying a focal point of the captured reflection light over the extended range of working distances.
The method may also include configuring the set of the pixels located in the central portion of the matrix with a number of rows smaller than the aforementioned predetermined number of rows, and with a number of columns smaller than the aforementioned predetermined number of columns.
The method may also include configuring each set as a single active pixel that is larger than each individual pixel.
The present invention will be further elucidated with reference to the figures of the exemplary embodiments.
SHORT DESCRIPTION OF THE SEVERAL
VIEWS OF THE DRAWINGS
The accompanying figures, in which the same reference numbers refer to identical or functionally identical elements in all individual views, are included in and form part of the description, together with the detailed description below, and serve to further clarify embodiments of concepts
BE2017 / 5663 comprising the claimed invention, and illustrate various principles and advantages of these embodiments.
FIG. 1 is a perspective view of an exemplary embodiment of an electro-optical palm reader for reading out targets by image recording in which an image processing module is attached in accordance with this description.
FIG. 2 is a schematic representation of components of image processing, exposure and distance measurement systems on board the image module within the reader of FIG. 1 for reading targets over a wide range of working distances.
FIG. 3 is an enlarged front view of a matrix of the image sensor of FIG. 2, and schematically depicts a set of the pixels located in a central portion of the matrix, for reading a distant target in a predetermined resolution in accordance with this description.
FIG. 4 is an enlarged front view of the matrix of the image sensor of FIG. 3, and schematically shows all pixels grouped in sets, for reading a nearby target in the substantially same predetermined resolution in accordance with this description.
FIG. 5 is a flow chart of steps performed in a method for reading out targets by image registration with a substantially constant resolution over a wide range of working distances in accordance with this description.
It will be clear to a person skilled in the art that parts are shown in the figures for simplicity and clarity and are not necessarily drawn to scale. For example, the dimensions and positions of some parts in the figures may be exaggerated relative to other parts, to help increase understanding of the embodiments of the present invention.
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The module, reader, and method components, when appropriate, are represented in the figures by conventional symbols, which show only those specific details relating to the understanding of the embodiments of the present invention, so as not to obscure the description with details that are readily apparent to those skilled in the art who have the advantage of the present disclosure.
DETAILED DESCRIPTION OF THE INVENTION
In accordance with an aspect of this description, an image processing module is operable to electro-optically read out targets, e.g., bar code symbols, by image recording with a substantially constant resolution over a wide range of working distances from the module. The module is provided with an image processing system which is provided with an image sensor, for example a two-dimensional, semiconductor device, such as a CCD device (charge coupled device) or a CMOS device (complementary metal oxide semiconductor), which is provided with a matrix of pixels for observing reflection light over a relatively narrow field of vision returning from a distant target, that is, a first target located at a distant working distance with respect to the module, and for observing reflection light returning over a relatively wide field of view from a nearby target, i.e., a second target located at a nearby operating distance from the module. The nearby working distance is preferably closer to the module than the distant working distance. The pixels preferably extend along common orthogonal, horizontal, and vertical center lines to sense the reflection light that returns from the targets along an imaginary center line that is substantially perpendicular to the horizontal and vertical center lines. The pixels are preferably arranged in a predetermined number of linear rows that are substantially parallel to the horizontal
BE2017 / 5663 center line, and in a predetermined number of linear columns that are substantially parallel to the vertical center line.
The module is also provided with a control that is operatively connected to the image processing system. The controller processes the observed reflection light from the distant target by only a set of the pixels located in a central portion of the matrix. The set of the pixels located in the central portion of the matrix preferably consists of a number of rows that is smaller than the aforementioned predetermined number of rows, and a number of columns that is smaller than the aforementioned predetermined number of columns . The controller also processes the observed reflection light from the nearby target by grouping all the pixels into sets, each set containing a multiple of pixels, and by processing the observed reflection light from the nearby target of each of the sets. Each set forms a single working pixel that is larger than each individual pixel. The controller processes the observed reflection light of the nearby target in a predetermined frame rate, and processes the observed reflection light of the distant target in a frame rate that is greater than the predetermined frame rate. Preferably, a distance measurement system is used to determine the working distance to each target.
In accordance with another aspect of this description, the aforementioned image processing module is mounted in a housing of an image reader which is provided with a light-transmitting window. The image sensor detects reflection light that comes back through the window from a target. The housing is preferably designed as a portable, point-of-transaction, pistol-shaped, hand-held housing, but can also be designed as a hand-held, box-shaped, or any other configuration provided with a hands-free configuration.
BE2017 / 5663
In accordance with yet another aspect of this description, a method of electro-optically reading out targets by image recording with a substantially constant resolution over a wide range of working distances from a matrix of pixels of an image sensor, is performed by over a relatively narrow field of view sighting of reflective light returning from a distant target located at a distant working distance from the matrix, and observing over a relatively broad field of vision reflecting light coming back from a nearby target located at a nearby working distance relative to the matrix of the matrix, and by processing the observed reflection light from the distant target by only a set of the pixels located in a central portion of the matrix. The method is further performed by processing the observed reflection light from the nearby target by grouping all pixels into sets, each set containing a plurality of pixels, and by processing the observed reflection light from the second target of each of the collections.
Referring now to the drawings, the reference number 30 in FIG. 1 is generally a hand-held image reader again for electro-optical reading of targets, such as bar code symbols or similar distinguishing marks. The reader 30 is provided with a housing 32 in which an image or scan motor or image module 40 is mounted, as described in detail below in connection with FIG. 2. The housing 32 is provided with a substantially elongated, tilted handle or lower handle part 28, and a barrel or upper body part which is provided with a front in which a light-transmitting window 26 is located. The dimensions of the cross-section and the entire size of the handle 28 are such that the reader 30 can be easily held in the hand of an operator. The body and handle parts can be made of a lightweight, resilient, shock-resistant,
BE2017 / 5663 self-supporting material, such as a synthetic plastic material. The plastic housing 32 can be injection molded, but it can also be vacuum-formed or blown to form a thin hollow sleeve that defines an inner space the volume of which is sufficient to contain the image module 40. A manually operable trigger 34 is movably mounted on the handle 28 in a forward-facing area of the reader 30. An operator's forefinger is used to energize the reader 30 to initiate reading by depressing the trigger 34. Although the housing 32 is explained as a portable, point-of-transaction, gun-forming, hand-held housing, this is only an example, because the housing can also be designed as a hand-held, box-shaped housing, or with any other configuration including a hands -free configuration.
As shown schematically in FIG. 2, the image processing module 40 is provided with an image processing system which is provided with an image sensor or image sensor 24 mounted on a printed circuit board (PCB) 22 in the reader 30, and an image lens assembly 20 positioned in front of the image sensor 30. The image sensor 24 and the image lens assembly 20 is preferably aligned along a center line or an optical image processing center 18 that is generally centrally located within the upper body portion of the housing 32. The printed circuit board 22 is preferably mounted within the tilted handle 28. The image sensor 24 is a semiconductor device, for example, a CCD (charge coupled device), or a CMOS device (complementary metal oxide semiconductor). The image sensor 24 has a two-dimensional array of addressable image sensors or pixels arranged in common orthogonal rows and columns, as described below in connection with FIGs. 3-4, which are parallel to the explained joint orthogonal, horizontal X-X center line and
BE2017 / 5663 vertical Y-Y center line. The image lens assembly 20 preferably comprises one or more lenses with variable focal length.
As also shown in FIG. 2, the array of pixels, in operation, observes a relatively narrow field of view (field of view FOW) 44 reflection light that comes back from a distant target 42 located at a distant working distance WD2 (working distance) relative to the module 40, and observes over a relatively wide field of view (FOV) 48 reflection light of a nearby target 46 located at a nearby operating distance WD1 relative to the module 40. In a preferred embodiment, WD1 is about half an inch from the window 26, and WD2 is about thirty inches and more from the window 26. The image lens assembly 20 is located far from the window, for example, about 40 millimeters away. The reflection light is scattered and / or reflected from each target across its respective field of view (FOV). The image lens assembly 20 captures the reflection light that passes through the window along the imaginary axis 18, and projects the captured reflection light onto the matrix of pixels. Each field of view (FOV) is substantially rectangular and extends along the aforementioned joint orthogonal, horizontal and vertical axes that are substantially perpendicular to the imaginary axis 18.
An illumination system can also be mounted in the module 40 and is provided with an illumination light source, for example, an LED (light emitting diode) 10, preferably mounted on the printed circuit board (PCB) 22, and an illumination lens assembly 12 configured to efficiently pattern of exposure on and over each target readable by image registration. At least a portion of the scattered and / or reflected reflection light is derived from the pattern of illumination light on and over each target. A distance measuring system can also be arranged in the module 40 and is provided with a distance meter 16 to determine the working distance to each target to be read. The range finder 16 may, for example, be a laser
BE2017 / 5663 or light beam, or send an ultrasonic signal to the target, and measure the working distance by determining when a return or echo signal is received.
As further shown in FIG. 2, the image sensor 24, the distance meter 16, and the exposure LED 10 are operatively connected to a controller or programmable microprocessor 36 that is operable to control the operation of these components. A memory 14 is connected to and accessible for the control 36. In operation, the control 36 transmits command signals to activate the range finder 16 to determine the working distances to the target, and also to activate the exposure LED 10 for a short exposure time, say 500 microseconds or less, and also to activate and expose the image sensor 24 to collect, only during said exposure time period, the reflection light, for example, exposure light and / or ambient light, from the targets. A typical matrix requires approximately 18-33 milliseconds to obtain the entire target image and operates at a frame rate of approximately 30-60 frames per second. The pixels produce electrical signals that correspond to a two-dimensional image of the target. The electrical signals are processed by the controller 36 into data indicative of the read target, and the data can be stored in the memory 14, or uploaded to a remote host for further processing. The controller 36 and the memory 14 can be placed on the printed circuit board (PCB) 22, which is supported by the module 40.
Resolutions of the image sensor 24 can be of different sizes. In a preferred embodiment, a 4 megapixel (MP) resolution of 2272 pixels in width along the horizontal axis is used at 1704 pixels in height along the vertical axis, with each pixel occupying an area of about 2 microns. These pixels are therefore arranged in a predetermined number of linear rows in the direction
BE2017 / 5663 of the horizontal center line, and in a predetermined number of linear columns in the direction of the vertical center line. A simplified version of the common orthogonal rows and columns of the image processing matrix is shown in FIGs. 3-4.
As described above, the resolution at which the target image is captured varies over the working distance range. A distant target is best read by a high-resolution image sensor, while a nearby target is best read at a low resolution. An aspect of this description is to read the targets with a substantially constant resolution over the working distance range.
For this purpose, the controller 36 operates to process the observed reflection light from the distant target 42 by only a set of pixels located in a central portion 50 of the matrix, as schematically depicted by the shaded area in FIG. 3. The controller 36 ignores or ignores the reflection light observed by the pixels located outside the central portion 50. This set of pixels located in the central portion 50 of the matrix consists of a number of rows smaller than the aforementioned predetermined number of rows, and from a number of columns that is less than the aforementioned predetermined number of columns. By way of numerical example, when the central portion 50 occupies one fourth of the entire area of the matrix of the 4MP image sensor, the resolution of the captured image is 1MP.
The controller 36 further operates by processing perceived reflection light from the nearby target 46 by grouping all pixels into sets, as schematically represented by the shaded areas 52 in FIG. 4. Each set 52 contains a plurality of pixels. As illustrated, each set 52 contains four individual or original pixels. Each set 52 forms a single one
BE2017 / 5663 active pixel that is larger than each individual pixel. The controller 36 processes the observed reflection light from the nearby target 46 in a predetermined frame rate, and processes the observed reflection light from the distant target 42 in a frame rate that is greater than the predetermined frame rate due to the lower number of pixels in the central portion 50 compared to the larger number of pixels in the entire matrix. The controller 36 processes the observed reflection light from the nearby target 46 of each of the sets 52. By way of numerical example, when each set 52 contains 2 x 2 original pixels, then each set is effectively 4 times larger than each original pixel and is the resolution one quarter of the entire surface of the matrix of the 4MP image sensor, in which case the resolution of the captured image is again 1 MP. Thus, the resolution is essentially the same for both distant and nearby targets.
As shown in the flow chart of FIG. 5, the method for electro-optically reading out targets by image recording with a substantially constant resolution over a wide range of working distances from the matrix of pixels of the image sensor 24 is performed, starting at initial step 60, by determining whether the target is located at a distant distance in decision step 62. If so, then in step 64 the observed reflection light from the distant target 42 is only processed by the set of pixels located in the central portion 50 of the matrix before ending in step 66. If not then, in step 68, all pixels are grouped into sets 52, each set 52 containing a plurality of pixels, and then, in step 70, the reflection light observed from each of the sets 52 is processed from the nearby target 46 before ending in step 66 .
Specific embodiments have been described in the foregoing description. However, it will be clear to a person skilled in the art that multiple adjustments and changes can be made without compromising
BE2017 / 5663 depart from the scope of the invention as set out in the claims below. Therefore, the description and the figures are to be considered as illustrative and not restrictive. All the aforementioned adjustments are deemed to fall within the scope of the present teaching. For a clear and concise description, the features are described herein as part of the same or different embodiments. However, it will be understood that the scope of the invention may include embodiments that have combinations of all or some of the features described. It will be clear that the embodiments shown have the same or identical parts, except where they are described as being different.
The benefits, solutions of problems, and any element that can realize any benefit or solution or make it more pronounced, should not be construed as a crucial, required, or essential feature or component in any or all of the claims. The invention is only defined by the appended claims, including some improvements made during the granting procedure of this application and all equivalents of those claims as granted.
In addition, related terms such as first and second, above and below, and the like, may only be used in this document to distinguish an entity or action from another entity or action, without necessarily requiring or implying an actual relationship or order between such entities or promotions. The terms "include," "including," "has," "including," "includes," "includes," "includes," or any other variation thereof, are intended as a non-exclusive inclusion, so that a process, method, article, or device that includes, includes, includes, contains a list of elements, not only those elements, but possibly contains other elements that are not explicitly listed or that are not inherent in such a process, method, article , or device. An element preceded by "includes ... a," "has ... a," "is
BE2017 / 5663 provided with ... a, "contains ... a," without further limitations, does not exclude the existence of additional identical elements in the process, method, object, or device provided of the element, or the element comprises, or contains. The term "one" is defined as one or more unless explicitly stated otherwise herein. The terms "substantially," "essential," "approximately," or any other variation thereof, are defined as being close to that understood by a person skilled in the art, and in a non-limiting embodiment, the term is defined as being within 10% , in another embodiment as being within 5%, in another embodiment as being within 1%, and in another embodiment as being within 0.5%. The term "coupled" as used herein is defined as connected, although not necessarily directly and not necessarily mechanically. A device or structure that is "configured" in a certain way is at least configured that way, but may also be configured in ways that are not listed.
It will be appreciated that some embodiments may include one or more generic or specialized processors (or "processing devices") such as microprocessors, digital signal processors, custom processors, and FPGAs (field-programmable gate arrays), and unique, stored program instructions (including both software and firmware) that control one or more processors to perform, in combination with certain circuitry without processors, some, most, or all functions of the method and / or device described herein. Alternatively, some or all of the functions may be performed by a state machine that has no stored program instructions, or in one or more application-specific integrated circuits (ASICs), in which each function or some combinations of the functions are implemented as custom logic. Naturally, a combination of the two approaches can be used.
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In addition, an embodiment may be embodied as a computer-readable medium provided with computer-readable code stored thereon for programming a computer (e.g., including a processor) to perform a method as described and claimed herein. Examples of such computer readable media include, but are not limited to, a hard disk, a CD-ROM, an optical storage device, a magnetic storage device, a ROM (read only memory), a PROM (programmable read only memory), a EPROM (erasable programmable read-only memory), an EEPROM (electrically erasable programmable read-only memory) and a flash memory. Furthermore, it can be expected that a person skilled in the art, despite possible significant difficulties and many design choices motivated by, for example, available time, current technology, and economic considerations, when guided by the concepts and principles described herein, is easily capable of carrying out minimal testing. will be to generate such software instructions and programs and integrated circuits.
The extract of the description is provided to enable the reader to quickly ascertain the nature of the technical description. It is submitted with the intention that it will not be used to explain or limit the scope of protection or the meaning of the claims. In addition, it can be seen in the foregoing detailed description that various features are grouped together in various embodiments for the purpose of simplifying the description. This method of describing should not be interpreted as expressing the intention that the claimed embodiments require more features than are explicitly stated in each claim. Rather, as the following claims show, inventive subject matter is contained in less than all the features of a single described embodiment. Thus are the following claims
BE2017 / 5663 hereby included in the detailed description, with each conclusion standing alone as a separately claimed subject matter. The mere fact that certain measures are cited in different claims gives no indication that a combination of these measures cannot be used to achieve an advantage. Many variants will be clear to the skilled person. All variants must be construed as being included in the scope of the invention as defined in the following claims.

权利要求:
Claims (20)
[1]
An image processing module for electro-optically reading targets by image registration with a substantially constant resolution over a wide range of working distances from the module, the module comprising:
- an image processing system provided with an image sensor provided with a matrix of pixels for observing reflection light over a relatively narrow field of view that comes back from a first target located at a first working distance with respect to the module, and for observing a relatively wide field of view of reflection light returning from a second target located at a second working distance relative to the module, the second working distance being closer to the module than the first working distance; and
- a control operatively connected to the image processing system and operable to process the observed reflection light of the first target by only a set of the pixels located in a central portion of the matrix, and further operable to process the observed reflection light from the second target by grouping all pixels into sets, wherein each set contains a plurality of pixels, and by processing the observed reflection light of the second target from each of the sets.
[2]
The image processing module according to claim 1, further comprising a distance measuring system for determining the working distance to each of the targets to be read out.
[3]
The image processing module according to claim 1 or 2, wherein the pixels extend along common orthogonal, horizontal and vertical axes for observing the reflection light that
BE2017 / 5663 returns from each of the targets along an imaginary center line that is substantially perpendicular to the horizontal and vertical center lines; and wherein the pixels are arranged in a predetermined number of linear rows that are substantially parallel to the horizontal axis, and wherein the pixels are arranged in a predetermined number of linear columns that are substantially parallel to the vertical axis.
[4]
The image processing module according to any of the preceding claims, wherein the image processing system is provided with an image lens assembly for capturing the reflection light, and for projecting the captured reflection light onto the image sensor to initiate capturing an image of the target, and wherein the image lens assembly has a variable focal point over the extended range of working distances.
[5]
The image processing module according to claim 3, wherein the set of the pixels located in the central portion of the matrix consists of a number of rows smaller than said predetermined number of rows, and a number of columns smaller than the aforementioned predetermined number of columns.
[6]
The image processing module according to any of the preceding claims, wherein each set forms a single active pixel that is larger than each individual pixel.
[7]
The image processing module according to any of the preceding claims, wherein the controller processes the sensed reflection light of the second target in a predetermined frame rate, and the sensed reflection light of the first target processed in a frame rate that is greater than the predetermined frame rate.
[8]
An image reader for electro-optically reading targets by image registration with a substantially constant resolution over a wide range of working distances from the reader, the reader comprising:
BE2017 / 5663
- a housing provided with a light-transmitting window; and
- an image processing module mounted in the housing, wherein the module is provided with an image processing system which is provided with an image sensor which is provided with a matrix of pixels for observing reflection light over a relatively narrow field of view which comes back through the window of a first target which is located at a first working distance with respect to the module, and for observing over a relatively wide field of view reflection light coming back from a second target which is situated at a second working distance with respect to the module, the second working distance being closer to the module then the first working distance; and
- a controller operatively connected to the image processing system and operable to process the observed reflection light from the first target by only a set of the pixels located in a central portion of the matrix, and further operable to process the observed reflection light from the second target by grouping all the pixels into sets, wherein each set contains a plurality of pixels, and by processing the observed reflection light from the second target of each of the sets.
[9]
The image reader of claim 8, further comprising a distance measuring system for determining the working distance to each of the targets to be read out.
[10]
The image reader according to claim 8 or 9, wherein the pixels extend along common orthogonal, horizontal and vertical axes for observing the reflection light returning from each of the targets along an imaginary centerline substantially perpendicular to the horizontal and vertical centerlines state; and wherein the pixels are arranged in a predetermined number of linear rows that are substantially parallel to the horizontal axis, and wherein the pixels are in a predetermined
BE2017 / 5663, a number of straight-line columns are arranged which are substantially parallel to the vertical axis.
[11]
The image reader according to any of the preceding claims 8-10, wherein the image processing system is provided with an image lens assembly for capturing the reflection light, and for projecting the captured reflection light onto the image sensor to capture an image of the target and wherein the image lens assembly has a variable focal point over the extended range of working distances.
[12]
The image reader of claim 10, wherein the set of the pixels located in the central portion of the matrix consists of a number of rows smaller than said predetermined number of rows, and a number of columns smaller than the aforementioned predetermined number of columns.
[13]
The image reader according to any of the preceding claims 8-12, wherein each set forms a single active pixel that is larger than each individual pixel.
[14]
The image reader according to any of the preceding claims 8-13, wherein the controller processes the observed reflection light of the second target in a predetermined frame rate, and the perceived reflection light of the first target processed in a frame rate that is larger then the predetermined frame rate.
[15]
A method for electro-optically reading targets by image registration with a substantially constant resolution over a wide range of working distances from a matrix of pixels of an image sensor, the method comprising:
observing reflection light over a relatively narrow field of view that comes back from a first target located at a first working distance with respect to the matrix, and for observing reflection light over a relatively wide field of view that comes back from a second target that
BE2017 / 5663 is located at a second working distance with respect to the matrix, the second working distance being closer to the matrix than the first working distance; processing the observed reflection light from the first target by only a set of the pixels located in a central portion of the matrix; and processing the observed reflection light from the second target by grouping all the pixels into sets, wherein each set contains a plurality of pixels, and by processing the observed reflection light from the second target of each of the sets.
[16]
The method of claim 15, further comprising determining the working distance to each of the targets to be read.
[17]
The method of claim 15 or 16, further comprising configuring the pixels to extend along common orthogonal, horizontal, and vertical center lines to sense the reflection light returning from each of the targets along an imaginary center line that is in is substantially perpendicular to the horizontal and vertical center lines; and arranging the pixels into a predetermined number of linear rows that are substantially parallel to the horizontal axis, and into a predetermined number of linear columns that are substantially parallel to the vertical axis.
[18]
The method of any one of the preceding claims 15-17, further comprising capturing the reflection light, and projecting the captured reflection light onto the matrix to initiate capturing an image of the target, and varying a focal point of the recorded reflection light over the extended range of working distances.
[19]
The method of claim 17, further comprising configuring the set of the pixels located in the central portion of the matrix with a number of rows that is smaller than the aforementioned predetermined
27 BE2017 / 5663 determined number of rows, and with a number of columns that is smaller than the aforementioned predetermined number of columns.
[20]
The method of any one of the preceding claims 15-19, further comprising configuring each set as a single one
5 operating pixel that is larger than each individual pixel.

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同族专利:

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公开号 | 公开日

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JP6449397B2|2019-01-09|

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GB201715227D0|2017-11-08|

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BE1025279B9|2019-03-04|

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BE1025279A9|2019-03-01|

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FR3056792A1|2018-03-30|

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US9798912B1|2017-10-24|

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GB2556667B|2019-12-04|

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CN107871097B|2020-11-06|

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CN107871097A|2018-04-03|

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AU2017208291A1|2018-04-12|

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BE1025279A1|2019-01-03|

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CA2975677A1|2018-03-26|

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GB2556667A|2018-06-06|

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DE102017121857A1|2018-03-29|

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JP2018055684A|2018-04-05|

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AU2017208291B2|2018-07-26|

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CA2975677C|2019-10-29|

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法律状态:
2019-02-04| FG| Patent granted|Effective date: 20190107 |

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US15276420|2016-09-26|

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