Optical arrangements for no-format wide-angle autofocus imaging lenses for high-resolution sensors

Abstract

Optical assembly (100) for imaging an object of interest, the optical assembly (100) comprising: a first lens holder (102) with a collar (108) having an inner flange (110) forming a spring seat (112); a first lens group (103) arranged within the first lens holder (102) along an optical axis (104) and configured to receive light from an object of interest; a second lens holder (105) with a collar (126) defining a chamber (128) and connected to the collar (108) of the first lens holder (102); a preload element (106) arranged in the chamber (128) of the second lens holder (105);and an optical element (107) with variable focus, arranged in the chamber (128) of the second lens holder (105) along the optical axis (104) and configured to receive light from the first lens group (103), wherein the biasing element (106) is arranged between the spring seat (112) and the optical element (107) with variable focus and is configured to exert a threshold force on the optical element (107) with variable focus; further comprising a second lens group (146) arranged in the second lens holder (105) along the optical axis (104) and configured to receive light from the optical element (107) with variable focus; wherein the first lens group (103) comprises a single lens and the second lens group (146) comprises a plurality of lenses.

Description

BACKGROUND

[0001] Scanning devices can capture images with a wide field of view (FOV) to effectively decode information within an image for use in machine vision applications. Furthermore, the increasing demand for portable sensors necessitates the use of smaller sensors that require active sensor alignment. Accordingly, portable scanning devices must be capable of operating with a large field of view while simultaneously producing sharp images across a work area for machine vision purposes.

[0002] Therefore, there is a need for improved systems, processes and devices that address these problems. DESCRIPTION

[0003] In one embodiment, the present invention is an optical assembly for imaging an object of interest, wherein the optical assembly comprises: a first lens holder with a collar having an inner flange forming a spring seat; a first lens group arranged within the first lens holder along an optical axis and configured to receive light from an object of interest; a second lens holder comprising a collar defining a chamber and coupled to the collar of the first lens holder; a biasing element arranged within the chamber of the second lens holder; and a variable-focus optical element arranged within the chamber of the second lens holder along the optical axis and configured to receive light from the first lens group.The preload element is positioned between the spring seat and the variable focus optical element and is configured to exert a threshold force on the variable focus optical element.

[0004] In one variant of this embodiment, the first lens holder includes a stop into which an end of the collar of the second lens holder engages to define a relative position between the first lens holder and the second lens holder.

[0005] In one variant of this embodiment, the engagement between the stop and the end of the collar of the second lens holder defines a distance between the first lens group and the optical element with variable focus.

[0006] In one variant of this embodiment, the optical assembly further comprises a flexible cable that is wrapped around the variable focus optical element, and the collar of the second lens holder defines a slot that accommodates the cable.

[0007] In one variant of this embodiment, the optical assembly further comprises an opening that is arranged between the optical element with variable focus and the second lens group.

[0008] In another embodiment, the present invention is an optical assembly for imaging an object of interest, the optical assembly comprising: a first lens holder with an internal thread; a first lens group arranged in the first lens holder along an optical axis and configured to receive light from an object of interest; a second lens holder with an external thread engaging with the thread of the first lens holder; a variable-focus optical element arranged in the second lens holder along the optical axis and configured to receive light from the first lens group; and a biasing element arranged in the second lens holder and configured to exert a threshold force on the variable-focus optical element.

[0009] In one variant of this embodiment, the optical assembly further comprises a spacer arranged in the second lens holder and positioned between the variable-focus optical element and the preload element. The spacer may have an inner surface that tapers outwards towards the variable-focus optical element to define an engagement surface at one end of the spacer. List of characters

[0010] The accompanying figures, in which identical reference numerals denote identical or functionally similar elements in the individual views, are incorporated into the disclosure together with the following detailed description and form an integral part of the disclosure and serve to further illustrate embodiments of concepts comprising the claimed invention described herein and to explain various principles and advantages of these embodiments. Fig. Figure 1 shows a cross-sectional view of an optical assembly for imaging an object of interest according to a disclosed example. Fig. Figure 2 shows an extended isometric view of the optical assembly of Fig. 1. Fig. Figure 3 shows an isometric view of the optical assembly of Fig. 1. Fig. Figure 4 shows a schematic representation of an image-based image processing device comprising a housing and an imaging system that is at least partially located in the housing.

[0011] Experts will recognize that elements in the figures are shown for the sake of simplicity and clarity and are not necessarily drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to improve the understanding of embodiments of the present invention.

[0012] Where appropriate, the apparatus and process components have been represented by conventional symbols in the drawings, which show only those specific details relevant to understanding the embodiments of the present invention, so as not to obscure the disclosure with details that are readily apparent to those skilled in the field who refer to the present description. DETAILED DESCRIPTION

[0013] Fig. Figure 1 shows a cross-sectional view of an optical assembly 100 for imaging an object of interest according to a disclosed example. The optical assembly 100 It can be used to obtain image data that can be decoded to identify, for example, barcodes and / or a target / object of interest within the image.

[0014] In the example shown, the optical assembly comprises100 a first lens holder 102 and a first group of lenses 103 , which are within the first lens holder 102 along an optical axis 104 is arranged. The optical assembly 100 also includes a second lens holder 105 , a prestressing element 106 and an optical element with variable focus 107 , which is inside the second lens holder 105 along the optical axis 104 is arranged and configured to direct the light from the first lens group 103 receives. In general, the lens holders are 102 , 105 coupled together in a way that forms the first lens group 103 and the optical element 107 aligns and also the pre-tensioning element 106 compresses, thereby compressing the preload element 106 a threshold force on the optical element 107exerts this effect. In this way, the optical assembly is held in place. 100 both the optical element 107 as well as the first lens group 103 fixed. Furthermore, the first lens holder 102 configured to center and tilt the first lens group 103 relative to other lens groups (e.g. the second lens group) of the optical assembly 100 controls what is explained further below.

[0015] The first lens holder 102 includes a collar 108 with an inner flange 110 , which has a spring seat 112 forms, and a lens seat 114 , which is the spring seat 112 opposite. The first group of lenses 103 , which as a single lens 116 As shown, it lies on the lens seat. 114 open and is in a front chamber 118 a second collar 119 of the first lens holder 102 opposite the collar108 arranged. The first lens group 103 It can be configured to receive light from an object of interest (not shown) and correct the overall distortion of the imaging lens. The first lens group 103 It can also partially compensate for the curvature field of the optical radiation. While the first lens group 103 as a single lens 116 As shown, the first lens group 103 include any number of lenses.

[0016] Similarly, the second lens holder includes 105 a collar 126 , which is a chamber 128 defined and with the collar 108 of the first lens holder 102 is connected. The collar 108 of the first lens holder 102 has a thread 129 , the one with the thread 130 (see Fig. 2) of the collar 126 of the second lens holder 105is engaged. To rotate the first lens holder. 102 relative to the second lens holder 105 to facilitate can bring an end 131 of the second collar 119 a pair of opposing slots 132 (see Fig. 2) define those configured to receive a tool (e.g. a screwdriver).

[0017] While the thread 129 of the first lens holder 102 Internal thread and the thread 130 of the second lens holder 105 External threads can be used for threading. 129 of the first lens holder 102 external thread and the thread 129 of the second lens holder 105 internal threads, or the lens holders 102 , 105 They can be connected to each other in different ways. For example, the lens holders can 102 , 105They can be coupled using a snap connection, a crimp rib and / or another type of fastening element to relieve the overpressure between the lens holders. 102 , 105 and / or on the optical element 107 to maintain.

[0018] In the example shown, the prestressing element 106 and the optical element 107 within the chamber 128 of the second lens holder 105 arranged. The prestressing element 106 is between the spring seat 112 and the optical element 107 arranged and configured to exert a threshold force of between approximately 7 Newtons (N) and 12 N on the optical element 107 exerts this effect. This is due to the prestressing element. 106 the threshold force on the optical element 107 exerts a reliable contact between the optical element. 107and maintain the corresponding electrodes, the optical element 107 held in a relatively fixed position to prevent shock events and / or over-compression of the optical element 107 avoided. In other words, the prestressing element can 106 a force on the variable optical element 107 exert an effect that prevents the optical element from 107 within the second lens holder 105 moves the optical element 107 protects against damage, ensures the proper functioning of the optical element 107 promotes and / or essentially facilitates the electrical contact between the optical element 107 and ensures the corresponding electrodes. In some examples, the preload element 106 a wave spring and the optical element 107At least one liquid lens or an adjustable lens. However, other types of preload elements and / or optical elements with variable focus may also prove suitable. For example, the preload element 106 for example, a coil spring, a disc spring, a curved spring, a finger spring, etc.

[0019] In the example shown, a spacer is used. 133 within the second lens holder 105 between the optical element 107 and the preloading element 106 arranged. The spacer 133 has an inner surface 134 , which extend outwards in the direction of the optical element 107 rejuvenated to create an intervention area 135 at one end of the spacer 133 to form. As a result, the spacer 133 a relatively wide spring seat surface 136 , where the prestressing element 106lies, and the thinner contact surface 135 The threshold force is concentrated on the optical element. 107 Furthermore, the thinner contact surface allows 135 , that a central part of the optical element 107 not the force of the preload element 106 is exposed.

[0020] To establish a relative position between the first lens holder 102 and the second lens holder 105 To define, the first lens holder contains 102 an attack 137 , which passes through the inner flange 110 and the collar 108 is defined. In the example shown, an intervention between the stop is defined. 137 and the end 138 of the collar 126 a distance between the spring seat 112 and the optical element 107 and positions the spring seat 112 , so that he can use the preload element 106compresses by a threshold distance. When the collar 126 on the attack 137 rests, a threshold distance is established between the first lens group 103 and the optical element 107 reached, and the spring seat 112 is positioned so that it engages the prestressing element 106 compresses and the preloading element 106 enables the threshold force to be applied to the optical element. 107 to exercise.

[0021] In the example shown, a flexible cable winds itself up. 139 around the optical element 107 and is used to create the optical element 107 to supply current via electrodes and the focal length of the optical assembly 100 to control the collar 126 of the second lens holder 105 defines a pair of opposing slots 140 (see Fig. 2), which the cable 139 record. The end 138 of the collar 126defines an opening 142 (see Fig. 2) for each of the slots 140 , which the cable 139 allows access to the slots 140 recorded and around the optical element 107 to be wrapped up.

[0022] The optical assembly 100 A second lens group can also be used. 146 and / or a third lens group 148 included, which are located within the second lens holder 105 along the optical axis 104 are arranged and configured to direct the light from the optical element 107 received. In the second lens group 146 It could be a Cooke triplet, which can be configured to correct pupillary errors of the imaging lens due to the aperture, and the third lens group 148 It can be configured to correct lens field curvature. In the example shown, the second lens holder defines 105an opening 150 , which are between the optical element 107 and the second lens group 146 is arranged. The optical element 107 is located on an area 151 of the second lens holder 105 , which opens 150 defined, adjacent to, or bordering on something else. In another example, the opening 150 a separate structure located within the second lens holder 105 is arranged and is located between the optical element 107 and the second lens group 146 is located.

[0023] While the first group of lenses 103 a single lens, the second lens group 146 a variety of lenses and the third lens group 148 containing a variety of lenses, each of the lens groups can 103 , 146 and / or 148 contain any number of lenses (e.g., 1, 2, 3, etc.) and / or one or more of the lens groups103 , 146 and / or 148 They can be omitted. Furthermore, additional or different lens groups can also be provided.

[0024] Fig. Figure 2 shows an extended isometric view of the optical assembly. 100 from Fig. 1. In the example shown, the first lens holder 102 an outdoor area 152 , the grooves 154 defined, which makes it easier for a person (or a tool) to access the first lens holder 102 to grasp while the lens holders 102 , 105 They can be screwed together. Fig. Figure 2 also shows that the slots 140 are rectangular and that the cable 139 a pair of spaced-apart ring-shaped sections 155 features that allow the passage of light and that are bent 156 of the cable 139 are interconnected.

[0025] Fig. Figure 3 shows an isometric view of the optical assembly. 100 from Fig. 1. Fig. 3 shows the first and second lens holders 102 , 105 , which are coupled together, and the cable 139 , which came out of one of the slots 140 stands out.

[0026] Fig. Figure 4 shows a schematic representation of an image-based image processing device. 200 , which is a case 202 and an imaging system 204 includes, at least partially within the housing 202 is arranged and the optical assembly 100 and an image sensor 206 includes a front opening. 208 is towards one end 210 of the case 202 arranged and the optical assembly 100 is between the front opening 208 and the image sensor 206 arranged. The front opening 208It can block light from objects outside the field of view to reduce imaging problems. Furthermore, the front aperture allows 208 in conjunction with the lenses of the lens groups 103 , 146 , 148 correct image formation on the image sensor 206 The front opening 208 can through the case 202 be defined or be a separately provided component.

[0027] In the example shown, the image processing device 200 an integrated power supply 211 and a circuit board 212 including a controller and / or memory that enables the operation of the optical assembly 100 and / or the image processing device 200 control. In some examples, the image processing device can 200Additional elements such as an illumination system configured to illuminate a target object for imaging may be included. The illumination system may comprise a light-emitting diode, a laser diode, a blackbody radiation source, or another light source and / or optics for scattering or focusing optical radiation to illuminate the object. The illumination system may be located within the housing. 202 may be located on one or more external surfaces of the housing, or be a separate device or component configured to illuminate the target object in order to obtain an image through the image processing device. 200 to capture. Other elements that are part of the image processing device 200 Examples of components that may be included are decoding systems, processors and / or circuits connected to the circuit board. 212are connected to enable the operation of the image processing device 200 to support, and / or a trigger that can be used to activate the optical assembly 100 to activate in order to capture an image.

[0028] Specific embodiments have been described in the foregoing description. However, a person skilled in the art will recognize that various modifications and changes can be made without altering the scope of protection of the invention as defined in the claims below. Accordingly, the description and figures are to be considered illustrative rather than limiting, and all such modifications are to be included within the scope of the present teachings. Furthermore, the described embodiments / examples / implementations are not to be understood as mutually exclusive, but rather as potentially combinable if such combinations are in any way permissive.In other words, any feature disclosed in one of the aforementioned embodiments / examples / implementations may be included in any of the other aforementioned embodiments / examples / implementations.

[0029] The benefits, advantages, solutions to problems, and all elements that may lead to the occurrence or enhancement of a benefit, advantage, or solution are not to be understood as critical, necessary, or essential features or elements in some or all of the claims. The invention is defined solely by the attached claims, including any amendments made during the pendency of this application and all equivalents of the granted claims.

[0030] Furthermore, in this document, relational terms such as first and second, upper and lower, and the like may be used merely to distinguish one entity or action from another, without necessarily requiring or implying any actual relationship or order of such an entity or action between such entities or actions. The expressions "includes," "comprising," "has," "have," "exhibits," "exhibiting," "contains," "containing," or any other variation thereof are intended to cover non-exclusive inclusion, such that a process, procedure, product, or device that includes, has, exhibits, or contains a list of elements may not only have those elements but may also have other elements not expressly listed or inherent in such process, procedure, product, or device. An element that "includes," "has," "exhibits," or "contains"The use of the term "a" does not, without further limitations, preclude the existence of additional identical elements in the process, method, product, or apparatus that includes, has, features, or contains the element. The terms "a" and "a" are defined as one or more unless expressly stated otherwise herein. The terms "essentially," "generally," "approximately," "about," or any other version thereof are defined in such a way as to be understood by a person skilled in the art in this field, and in one non-restrictive embodiment, the expression is defined as within 10%, in another embodiment as within 5%, in yet another embodiment as within 1%, and in yet another embodiment as within 0.5%. The term "coupled," as used herein, is defined as connected, but not necessarily directly and not necessarily mechanically.A device or structure that is “configured” in a certain way is at least also configured in that way, but may also be configured in ways that are not listed.

[0031] The summary of the disclosure is provided to enable the reader to quickly ascertain the essence of the technical disclosure. It is provided with the understanding that it is not intended to be used for interpreting or limiting the scope or meaning of the claims. Furthermore, it can be inferred from the preceding detailed description that various features in different embodiments have been summarized for the purpose of streamlining the disclosure. This type of disclosure is not to be interpreted as reflecting the intention that the claimed embodiments require more features than are expressly stated in each claim. Rather, as the following claims demonstrate, the inventive step lies in fewer than all the features of a single disclosed embodiment.The following claims are hereby incorporated into the detailed description, each claim being a separately claimed subject matter.

Claims

[1] Optical assembly for imaging an object of interest, the optical assembly comprising: a first lens holder with a collar having an inner flange forming a spring seat; a first lens group arranged within the first lens holder along an optical axis and configured to receive light from an object of interest; a second lens holder with a collar that defines a chamber and is connected to the collar of the first lens holder; a preload element arranged in the chamber of the second lens holder; and an optical element with variable focus, arranged in the chamber of the second lens holder along the optical axis and configured to receive light from the first lens group, wherein the preload element is arranged between the spring seat and the variable focus optical element and is configured to exert a threshold force on the variable focus optical element. [2] Optical assembly according to claim 1, wherein the collar of the first lens holder has a thread which engages in the thread of the collar of the second lens holder. [3] Optical assembly according to claim 2, wherein the thread of the first lens holder is an internal thread and the thread of the second lens holder is an external thread. [4] Optical assembly according to claim 1, wherein the first lens holder has a stop which engages with an end of the collar of the second lens holder to define a relative position between the first lens holder and the second lens holder. [5] Optical assembly according to claim 4, wherein the stop is defined by the inner flange of the first lens holder. [6] Optical assembly according to claim 4, wherein the engagement between the stop and the end of the collar of the second lens holder defines a distance between the first lens group and the optical element with variable focus. [7] Optical assembly according to claim 4, wherein the engagement between the stop and the end of the collar of the second lens holder defines a distance between the spring seat and the variable focus optical element and causes the spring seat to compress the preload element. [8] Optical assembly according to claim 1, further comprising a flexible cable wrapped around the variable focus optical element, wherein the collar of the second lens holder defines a slot that receives the cable. [9] Optical assembly according to claim 8, wherein one end of the collar of the second lens holder defines an opening of the slot. [10] Optical assembly according to claim 8, wherein the slot is a pair of opposing slots defined by the collar of the second lens holder. [11] Optical assembly according to claim 1, wherein the first lens holder has a second collar opposite the first collar which accommodates the first lens group. [12] Optical assembly according to claim 11, wherein an end of the second collar defines a pair of opposing slots configured to accommodate a tool to facilitate the rotation of the first lens holder relative to the second lens holder. [13] Optical assembly according to claim 1, wherein an outer surface of the first lens holder has grooves. [14] Optical assembly according to claim 1, wherein the preload element comprises a wave spring. [15] Optical assembly according to claim 1, further comprising a second lens group arranged in the second lens holder along the optical axis and configured to receive light from the variable focus optical element. [16] Optical assembly according to claim 15, wherein the second lens holder defines an opening arranged between the variable focus optical element and the second lens group. [17] Optical assembly according to claim 15, further comprising an opening arranged between the optical element with variable focus and the second lens group. [18] Optical assembly according to claim 1, wherein the optical element with variable focus is at least one of a liquid lens or an adjustable lens. [19] Optical assembly according to claim 1, wherein the first lens group comprises a single lens and the second lens group comprises a plurality of lenses. [20] Optical assembly for imaging an object of interest, the optical assembly comprising: a first lens holder with an internal thread; a first lens group arranged within the first lens holder along an optical axis and configured to receive light from an object of interest; a second lens holder with an external thread that engages with the thread of the first lens holder; an optical element with variable focus, arranged within the second lens holder along the optical axis and configured to receive light from the first lens group; and a prestressing element that is positioned within the second lens holder and configured to exert a threshold force on the variable focus optical element. [21] Optical assembly according to claim 20, further comprising a spacer arranged inside the second lens holder and positioned between the variable focus optical element and the preload element. [22] Optical assembly according to claim 21, wherein the spacer has an inner surface that tapers outwards in the direction of the variable focus optical element to define an engagement surface at one end of the spacer.

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