Rack code scanner

Abstract

A scanner for reading codes printed on vials stored in a rack comprises a camera and a support for holding the rack above the camera, the support being arranged to hold the rack without a glass panel, so that air can freely circulate around the rack. This prevents issues with prior art systems where condensation can form on a glass support that hinders reading of the codes. The scanner may also have open sides, or other ventilation, further encouraging circulation of air around the rack. The scanner may have a lighting system to illuminate the base of the rack, preferably indirectly, via reflection from the base and other parts of the scanner.

Description

[0001] Rack Code Scanner

[0002] The present invention relates to code scanners, and more particularly to code scanners as frequently found in laboratories, where test tubes or vials, onto which machine-readable codes are printed, are stored and used in racks, for example to enable bulk processing of samples.

[0003] It is commonplace in some laboratories for test tubes to be held collectively in racks. This allows convenient storage and manipulation, either by hand or by automated processing equipment. The racks tend to be standardized, so that they are compatible with processing equipment commonly supplied by many different manufacturers. A system knows as the SBS (Society for Biomolecular Screening) standard rack system is a common standard, where each rack is designed to store a defined quantity of test tubes, with the maximum quantity per rack typically being 24, 48, 96, 128 or 384 depending on the size of the tube, with the overall size of the rack being the same for each. These tubes are stored in a rectangular array. Other formats exist, such as the “CRYO” racks, that are in a square format and hold a plurality of tubes, again generally with machine-readable codes visible on the undersides thereof. Other formats may be arranged to hold a different amount of test tubes, again, typically in a rectangular array.

[0004] The tubes are generally made of durable, chemically resistant plastic, such as polypropylene, polystyrene or polycarbonate, and typically have flat bases, allowing them to stand upright on a table etc. Each tube generally has a unique, machine-readable code imprinted on the base thereof, to allow identification and tracking of it, as it goes through its various stages of processing and storage etc. The codes are typically bar codes, either 1D or 2D, and hence are computer-readable, when a suitable scanner is used, but other codes such as QR codes may also be used, some of which may also be human-readable codes. When the tubes are stored in the SBS or CRYO racks the codes are visible on the underside of the racks. Code scanners exist that are able to read the codes, either individually, or collectively. These scanners are typically boxes with a glass reading plate on an upper surface thereof, that sit on a tabletop. For example, an SBS rack fully filled with test tubes can be placed on a scanner, and the scanner can photograph the bases of all test tubes simultaneously and, using image processing techniques (either in the scanner or in an attached computer), extract the code from each tube. Software can then process the codes as required.It is commonplace for the SBS, CRYO, and other racks to be stored in chilled conditions such as in a refrigerator, a freezer, or under cryogenic conditions. When reading such racks that are still cold, the glass platforms on the readers can become fogged with ice or condensation, which affects the ability for the camera within the scanner to see the tubes clearly, making it harder to get an accurate reading of all the codes on the corresponding test tubes in the racks. Also, the underside of the glass can too become fogged, and it is difficult or impossible to access the underside to clean it. This can mean time is lost in cleaning the scanner between uses, or waiting for the glass panel to clear.

[0005] It is an object of the present invention to provide an alternative code scanner.

[0006] According to a first aspect of the present invention there is provided a code scanner for simultaneously reading codes present on multiple test tubes stored in a rack, the scanner comprising a base and a support structure for supporting a rack on two or more points on edges of the rack and defining a reading area, the support structure being open and further comprising one or more struts arranged to hold a rack in an elevated position over the base, with a lower region of the rack arranged to occupy the reading area when held by the support structure, said base incorporating a camera directed upwards towards the reading area, the base, supporting structure and reading area defining a volume, and the scanner further comprising at least one light source arranged to illuminate the reading area with indirect lighting reflected from a part of the reader, and wherein the support structure is adapted to support the rack without a transparent, solid base under the rack between the rack and the camera port.

[0007] Embodiments of the invention therefore provide for a code scanner that is able to take images of the base of a rack, and so to provide images from which codes present on the base of any test tubes on the rack may be read, with a base of the rack located in the reading area, wherein the reading area does not require a glass or other transparent base for the rack to sit on. The open arrangement means that the volume between the reading area and the camera is vented, hence allowing air to circulate, and so reduce the chances of any fogginess that can degrade the quality of images taken by the camera. It is often the case that racks are stored in chilled, frozen, or even cryogenic (all regarded generally as “chilled” in this specification) conditions prior to the codes being read, and this can result in the racks becoming frosty or damp, as they sit in a laboratory warming up, and this can transfer moisture onto surfaces on which the racks are placed. With prior art code scanners that have a glass base for the rack to sit on during the reading process, thismoisture can transfer to the glass base and make the code reading process unreliable. By having a reading area that is open, with no solid material between the camera port and the reading area, this problem is alleviated. Hence, in embodiments the support structure is adapted to support the rack without a transparent, solid base under the rack, between the rack and the camera port. The rack hence does not sit on a transparent material at the reading area, and the camera is able to image, from the camera port, the base of the rack without intervening transparent material at the reading area. This provides the open nature of the scanner, and hence prevents or reduces problems due to condensation.

[0008] In some embodiments the images obtained by the camera may be processed using a processor within the scanner to extract digital data relating to the codes printed on the bases of test tubes. In other embodiments the images obtained may be passed to a connected computer which may use image processing software to extract the digital data relating to the codes.

[0009] In some embodiments the support structure comprises one or more rails, for supporting corresponding opposed edges of a rack. The racks are generally rectangular, with the test tubes held by the rack being positioned in a square array within the rack, so leaving the edges free of any test tubes, and hence providing a region for supporting the rack without interfering with the area in which the test tubes sit.

[0010] In some embodiment a rail is arranged to hold all of the edge of the base. In other embodiments there may be a plurality of shorter rails, each arranged to support a rack on a part of its base at the edge thereof. In a preferred embodiment there is a rail arranged to support a rack at each corner thereof.

[0011] Advantageously, in some embodiments the rails have a vertically extending lip for preventing lateral movement of the rack when in position. This allows the racks to be conveniently positioned on the rails and for them to sit in position positively located, with a sufficient amount of the base positioned under the rail to prevent the rack from slipping off the rails.

[0012] In some embodiments the lip on each rail extends for the length of a side of a rack for which they are arranged to support, and also partially extend around to other sides to provide support to corners of the rack. This prevents the rack from slipping off the rails in any horizontal direction, and provides for a consistent positioning of the rack on the scannerwhen placed on the rails.

[0013] As explained above, some embodiments are arranged to hold a rack in place by providing a horizontal base under one or more parts of the rack, such as one or more rails, that supports a part of the base of a rack. Other embodiments may be arranged to grip a rack from the side, so leaving the entirety of the base free to be imaged with the camera. Thus, in some embodiments, a rack may be arranged to be pinched between two opposing grips, each of which is arranged to push against a side of a rack, to hold it in a fixed position, with the base of the rack in the reading area. Some embodiments may combine the two approaches, and provide both a grip to the side of a rack, and also provide a horizontal support under one or more parts of the rack.

[0014] In some embodiments the scanner further comprises a pair of struts, each strut holding a rail. The struts provide a convenient means for supporting the rails at a suitable height for the camera to be able to have, in its field of view, a view of the whole of the reading area and hence a view of all test tubes properly located in a rack.

[0015] In some embodiments the scanner is generally rectangular in planform, and the struts are positioned at opposed ends of the base, the opposed ends raised up to define opposed sides of the volume within the scanner and above the base, the opposed sides comprising the struts, and wherein the camera is arranged to view a base of the rack through the volume when a rack is seated on the support structure. Thus, in such embodiments, the scanner comprises a generally rectangular base with a pair of opposed sides, that comprise the struts, that are raised up from the base, on which a rack may be seated.

[0016] One or more side regions of the support structure may allow access to air, to allow ventilation of the volume under the reading area when a rack is located on the scanner. The access may comprise of one or more ventilation ports in a rack support, or may comprise one or more gaps or ports, or open regions in the rack support structure. Such gaps etc. may allow free passage of air from the surrounding environment.

[0017] Preferably, in some embodiments, the volume is at least partially open on the sides not forming the struts, allowing air to flow through the volume. Thus such embodiments allow moist air, that may be present around the rack to dissipate through convection, reducing the likelihood of moisture forming on the camera or on the test tubes of the rack, which may interfere with the code reading process. Preferably therefore, in some embodiments, thevolume is fully open on two sides thereof.

[0018] Some embodiments may have ventilation that allows air to freely flow through the volume, but which also incorporates a fan to provide improved throughput of air, so aiding the ventilation. Some embodiments may further incorporate means for detecting an atmosphere that isn’t conducive to obtaining good images of the codes present on the test tubes, such as a fog sensor or a temperature sensor within the volume. The means for detecting such an atmosphere may be used to activate or control a ventilation fan.

[0019] Conveniently, in some embodiments the light source is located on or adjacent the support structure. The light source may be located in a strut. There may be a light source positioned in each strut. The light source or sources may be arranged to shine light into the volume, the light being used to illuminate the reading area.

[0020] Advantageously, in some embodiments, the or each light source is arranged to direct light towards the base of the scanner, with reflections therefrom providing illumination to the reading area. Thus, the reflection of the light from the base helps to provide a uniform illumination to the reading area. Advantageously therefore the base of the scanner may comprise a reflective surface, such as a pale or white surface, and more preferably a matt reflective surface, to provide an even light distribution from reflections therefrom. The base may be painted with a suitable paint to enhance the reflectivity.

[0021] In some embodiments the or each light source has a baffle preventing light travelling from the light source directly to the reading area. It has been found that light illuminating the reading area, and hence the bases of test tubes sitting at the reading area, directly from a particularly acute angle can make it harder for the camera to produce a good image of the codes present on the bases of the test tubes. If the light sources are located on the struts, then the baffles prevent such direct light from reaching the reading area. Instead, the light will reach the reading area due to reflections from other parts of the scanner, such as the base and support structure. To this end, advantageously the base, and / or inner sides of the support structure may be coated with a light coloured, diffuse coating, such as a light coloured matt paint.

[0022] To further assist the illumination process, in some embodiments the base comprises a baseplate that has the camera mounted centrally therein, and wherein the baseplate has a plurality of differently angled regions arranged to reflect light from the light sources todifferent parts of the reading area. The angled regions help to provide a more uniform illumination over the whole of the reading area.

[0023] In some embodiments the planform external dimensions of the base match that of the size of the rack that the scanner is designed to scan. This allows the scanner to sit conveniently in a storage area designed to store multiple racks in an efficient manner. Also, by having a base that matches the size of the rack it is designed to hold, then the scanner is generally able to fit into an automation machine without said machine requiring any modification.

[0024] Embodiments of the invention are further described hereinafter, by way of example only, with reference to the accompanying drawings, in which:

[0025] Figure 1 diagrammatically illustrates an example of a prior art code scanner for multiple test tubes mounted in a rack;

[0026] Figure 2 diagrammatically illustrates an SBS rack showing the underside thereof with a view of the bases of test tubes held in the rack;

[0027] Figure 3 diagrammatically illustrates a perspective view of a first embodiment of the present invention; and

[0028] Figure 4 diagrammatically illustrates a front view of the first embodiment.

[0029] Note that the figures are not drawn to scale.

[0030] Shown at Figure 1 is a generic prior art code scanner for test tubes in an SBS rack. The scanner 10 comprises of a generally rectangular metal enclosure 12 with an upper surface 14 having a rectangular aperture 16 formed therein, and with a transparent glass window 18 sitting in the aperture at a level lower than that of the upper surface. Inside the enclosure 12, and not visible in the figure is a camera sensor arranged near the base of the unit, and which is arranged to look up towards the aperture in the upper surface. There are also lights inside the enclosure provided to illuminate the aperture to allow the camera to photograph items placed therein. Various other electronic systems to control the camera and lights, and to provide a link to external computer, are also provided, and not shown.Shown at Figure 2 is a view of the underside of an SBS rack 20 that is designed to hold, in this instance, forty eight test tubes, e.g. 22. Each of the tubes 22 has a flat base 24, onto which is printed a machine readable code, typically a 2D bar code. The rack holds the tubes with the bases all at the same plane, and in an array of 6x8 tubes. The rack has structural elements (not shown) that hold each test tube in position, with the bases being visible to cameras or human readers. The rack 20 has vertical sidewalls 26 around its perimeter. The rack is rectangular, and of a well defined, standardized dimension, as defined by the SBS standard.

[0031] Referring to both Figure 1 and Figure 2, when in use, the SBS rack 20 is placed on the scanner 10 such that it sits in the aperture 16, and on top of the transparent window 18. The base of the SBS rack is then visible to the camera inside the enclosure. A computer system within the scanner is arranged to control the camera sensor so as to take images when demanded by a connected computer system (not shown). The connection to a further computer system allows the further computer system to communicate with the scanner to instruct it to take images as required and to receive images taken by the camera, the code data extracted by image processing software running on the connected computer system. The further computer system may be arranged to control other elements of the code scanner, such as lighting intensity, data export options, any other parameters and settings as would be understood by a person of ordinary skill in the art.

[0032] If the rack has recently come from a refrigerated unit, then it may be cold, and potentially also icy. As it warms it may get wet from condensation or melting ice, and this moisture can easily get transferred to the transparent window 18, where it can hinder the reading of codes on the tubes in the rack, or that of other racks placed on the window. The window can therefore require frequent cleaning when in busy use, or codes can be missed during the reading process.

[0033] Figures 3 and 4 show different views of an embodiment of the present invention. The embodiment shows a code scanner 40 that comprises a generally rectangular base portion 42, and two support structures 44, 46, rising up from opposed edges of the base 42. The support structures constitute a pair of struts that hold corner rails 48a-d, for supporting a rack of test tubes, such as rack 20 from Figure 2. The base 42 has a central port 50 in which is mounted a camera, the camera arranged to point upwards, and to be focused at a plane defined by the corner rails 48. The region of this plane between the corner railsconstitutes a reading area, and the plane is where the bases of test tubes mounted in a rack will lie, when a rack is positioned onto the scanner 40. The space between an upper surface of the base, and the reading area defines a volume through which the base of the rack is illuminated and viewed by the camera.

[0034] Both support structures are similar. Support structure 44 has a light source (not shown), comprising a strip of LED emitters, in housing 52. In this embodiment the LED emitters comprise a strip of sixteen 5050 LEDs. The support has a channel 54 set below the light source that allows light from the emitters in housing 52 to shine down onto an upper surface 56 of the base 42. A cover plate 53 covers a cable channel that supplies power to the LED lights that sit above light channel 54 The light from the light source illuminates substantially the whole of the base 56, including regions 62, 64, 66, 68 and 50. It also illuminates at least part of the opposite support structure.

[0035] A baffle 58 is positioned adjacent the LED emitters that prevents light from the emitters from directly illuminating the reading area. Thus, when a rack is in position with its base sat at the reading area, then any light from the emitters that reaches the reading area will be reflected light, with most of that light having been reflected from the base and the opposing support structure. It has been found that this provides better, more even illumination to the bases of the test tubes for the purposes of the camera and subsequent digital image processing being able to reliably read the codes printed on the tubes.

[0036] Each of the corner rails 48 comprise a horizontal shelf 70 and a wall 72. A rack, when placed on the rails sits with a part of each corner sat on a corresponding shelf 70 of each corner rail, while the wall 72 ensures the rack is seated in a well defined position and prevents lateral movement in one horizontal dimension. A further wall 74 is arranged to maintain position of the rack in an orthogonal horizontal dimension, preventing the rack from sliding out of position. Each shelf 70 has a horizontal depth of 4mm, which is large enough to provide a secure support, but not so large that it will interfere with any codes on tubes in a rack that is being supported.

[0037] The height of the shelf 70 above the base is chosen based upon the ability of the camera present in the base to obtain an image of a rack positioned on the scanner, that is of sufficient quality to allow codes on test tubes present on the rack to be read reliably. In this embodiment the height of the shelf above the base, and hence above the camera, isThe camera port 50 has a coated glass covering sitting flush with top of the port to protect the camera lens below it from dust and debris, and which also provides for easy cleaning, as there are no nooks for dust to collect, and also reduces glare and / or light spikes from the illumination means. The port 50 sits in a raised, central position on the upper surface of the base 56. The upper surface 56 of the base is divided up into five different regions, with region 60 holding the port 50 centrally positioned around the others. Each other region 62, 64, 66, 68 is inclined to the horizontal, rising up from where it meets an edge of the base to where it meets the central region 60. The incline is at 10° from the horizontal. This angle has been found to give good light coverage due to the reflectivity of the base, but clearly other embodiments may have different inclines, or no incline at all. Light from the emitters above channel 54 will be illuminating all of these regions, and some of the light reflecting from them will illuminate the reading area. Region 64 will provide a significant contribution of the light from the emitters above channel 54 due to those emitters being directed downwards from that channel and hitting that region, which due to its angle, is facing the emitters more directly than the other region. Similarly, region 62 will provide a significant degree of the illumination to the reading area from a light source mounted in the other support structure 46. The other regions, 60, 66 and 68 will all also contribute, due to the base, and internal surfaces of the support structure being coated in a reflective, white paint having a matt finish.

[0038] The support structures 44, 46 sit on opposed sides of the rectangular base 42. The remaining two sides of the base 42 are open, allowing air to circulate freely through the volume when in use, even with a rack mounted in position on the rails 48. Chilled air, as may arise from air circulating around a rack that has been removed from a chilled environment such as a freezer, or from other cold environment, can become foggy, and hence can result in an uncooperative environment for retrieving good images of any codes on the bases of test tubes on a rack. The open sides allow such chilled air to be ventilated, due to normal air convection in the laboratory, or wherever the scanner is situated for use. And as the rack sits on corner rails, rather than on a glass sheet, there are no surfaces near to the rack to fog up with moisture from such chilled air, and interfere with the code reading process.

[0039] In this embodiment two sides are completely open, but other embodiments may have a differing amount of openness to air convection, either by having support structures that provide a smaller covering of the volume, or by having more, but still allowing someventilation to occur. Some embodiments may have a fan to aid the movement of air, and the fan may be switchable, controlled by a manual switch or an automatic switch, operable by a sensor for detecting fog, or likely fog conditions.

[0040] The scanner may be made of any suitable material. The embodiment described in relation to Figures 3 and 4 is made from machined aluminium. Other embodiments may comprise, for example, cast aluminium, with the base and support structure formed as a single item, or the base and sides may be made separately and fastened together. It may also be made from other materials according to requirements of a user, such as steel, a metal alloy, or a hard plastic.

[0041] To further clarify the invention, it may comprise a scanner for reading codes printed on vials stored in a rack comprises a camera and a support for holding the rack above the camera, the support being arranged to hold the rack without a glass panel, so that air can freely circulate around the rack. This prevents issues with prior art systems where condensation can form on a glass support that hinders reading of the codes. The scanner may also have open sides, further encouraging circulation of air around the rack. The scanner may have a lighting system to illuminate the base of the rack, preferably indirectly, via reflection from the base and other parts of the scanner.

[0042] The functions described herein as provided by individual components could, where appropriate, be provided by a combination of components instead. Similarly, functions described as provided by a combination of components could, where appropriate, be provided by a single component.

[0043] Throughout the description and claims of this specification, the words “comprise” and “contain” and variations of them mean “including but not limited to”, and they are not intended to (and do not) exclude other moieties, additives, components, integers or steps. Throughout the description and claims of this specification, the singular encompasses the plural unless the context otherwise requires. In particular, where the indefinite article is used, the specification is to be understood as contemplating plurality as well as singularity, unless the context requires otherwise.

[0044] Features, integers or characteristics, described in conjunction with a particular aspect, embodiment or example of the invention are to be understood to be applicable to any otheraspect, embodiment or example described herein unless incompatible therewith. All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and / or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and / or steps are mutually exclusive. The invention is not restricted to the details of any foregoing embodiments.

Claims

Claims1. A code scanner for simultaneously reading codes present on multiple test tubes stored in a rack, the scanner comprising a base and a support structure for supporting a rack on two or more points on edges of the rack and defining a reading area, the support structure being open and further comprising one or more struts arranged to hold a rack in an elevated position over the base, with a lower region of the rack arranged to occupy the reading area when held by the support structure, said base incorporating a camera directed upwards towards the reading area, the base, supporting structure and reading area defining a volume, and the scanner further comprising at least one light source arranged to illuminate the reading area with indirect lighting reflected from a part of the reader and wherein the support structure is adapted to support the rack without a transparent, solid base under the rack between the rack and the camera port.2 A code scanner as claimed in claim 1 wherein the support structure comprises one or more rails, for supporting edges of a rack.

3. A code scanner as claimed in claim 2 wherein the or each rail has a lip for preventing lateral movement of a rack when in position on the rail.

4. A code scanner as claimed in claim 2 or claim 3 wherein the rails are arranged to support each corner of a rectangular rack.

5. A code scanner as claimed in any of the above claims wherein the scanner further comprises one or more grips for gripping a sidewall of a rack, and for holding it in a fixed position.

6. A code scanner as claimed in any of claims 2 to 5, wherein the support structure comprises a pair of struts, each strut holding one or more rails.

7. A code scanner as claimed in any of the above claims wherein the scanner is generally rectangular in planform, and the struts are positioned at opposed ends of the base, the opposed ends raised up to define opposed sides of the volume within the scanner and above the base, the opposed sides comprising the struts, and wherein the camera is arranged to view a base of a rack through the volume when a rack is seated on the support structure.

8. A code scanner as claimed in claim 7 wherein the volume is at least partially open to the atmosphere on the sides not forming the struts, allowing air to flow through the volume.

9. A code scanner as claimed in any of the above claims wherein the volume is fully open to the atmosphere on at least two sides thereof.

10. A code scanner as claimed in any of the above claims further comprising a fan for providing forced air convection of the volume.

11. A code scanner as claimed in any of the above claims wherein the light source is located on or adjacent the support structure.

12. A code scanner as claimed in claim 11 wherein each strut has a light source attached thereon, each light source arranged to shine light into the volume.

13. A code scanner as claimed in any of the above claims wherein the or each light source is arranged to direct light towards the base of the reader, with reflections therefrom providing illumination to the reading area.

14. A code scanner as claimed in claim 12 or claim 13 wherein the or each light source has a baffle preventing light travelling from the light source directly to the reading area.

15. A code scanner as claimed in any of claims 12 to 14 wherein the base comprises a baseplate that has the camera mounted centrally therein, and wherein the baseplate has a plurality of angled regions arranged to reflect light from the light sources to different parts of the reading area.

16. A code scanner as claimed in any of the above claims wherein the planform dimensions of the base match that of the size of the rack that the scanner is designed to scan.

17. A code scanner as claimed in any of the above claims wherein the external dimensions of the base of the scanner match that of the planform dimensions of an SBS rack.

18. A code scanner as claimed in any of claims 1 to 16 wherein the external dimensions of the base of the scanner match that of the planform dimensions of a CRYO rack.

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