Spatial filters for optical time-of-flight sensors

Abstract

Improved optical Time-of-Flight (ToF) object presence detection techniques are disclosed. In some implementations, a spatial filter is coupled to an optical ToF sensor to reduce the angle of the illumination cone produced by an emitter of the ToF sensor and / or the FOV of the detector of the ToF sensor. In some implementations, the spatial filter may include a tube and / or a passage aligned with the emitter and / or the detector of the ToF sensor. In some implementations, the spatial filter may be a Micro Honeycomb Spatial Filter (MHSF) or a Micro Spatial Filter (MSF). In some implementations, the spatial filter may allow the ToF sensor to reliably detect objects, such as blood culture bottles.

Description

SPATIAL FILTERS FOR OPTICAL TIME-OF-FLIGHT SENSORSCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to and the benefit of United States Provisional Application No. 63 / 619,925, which was filed on January 11, 2024, and is incorporated by reference herein in its entirety.TECHNICAL FIELD

[0002] Aspects of the present technology relate to automated systems and methods for detecting objects, such as blood culture bottles.BACKGROUND OF THE INVENTION

[0003] The presence of biologically active agents, such as bacteria in a patient’s body fluid, especially blood, is generally determined using culture bottles, such as the BD BACTEC™ culture bottles, which are manufactured and sold by Becton, Dickinson and Company. The culture bottles may contain a blood culture media, such as the BD BACTEC™ Peds Plus™ medium, BD BACTEC™ Plus Aerobic medium, BD BACTEC™ Plus Anaerobic medium, BD BACTEC™ Lytic Anaerobic medium, BD BACTEC™ Standard Aerobic medium, BD BACTEC™ Standard Anaerobic medium, BD BACTEC™ Myco medium, BD BACTEC™ Mycosis medium, BD BACTEC™ Aerobic Platelet medium, or BD BACTEC™ Anaerobic Platelet medium, all of which are manufactured and sold by Becton, Dickinson and Company. To test for the presence of biologically active agents, a small quantity of blood or other bodily fluid is injected through an enclosing rubber septum into a sterile culture bottle containing a culture medium, and the bottle is then incubated at about 35-37°C (e.g., 36.5°C) and monitored for microorganism growth. Microbial growth may be detected by a change in the blood culture over time. Parameters, such as the concentration of carbon dioxide or oxygen in the culture bottle headspace or a change in pH, may be monitored for changes over time that are indicative of microbial growth.

[0004] Since it is of utmost importance to learn if a patient has a bacterial infection, hospitals and laboratories have automated apparatus that may process many blood culture bottles simultaneously. One example of such an apparatus is the BD BACTEC™ FX blood culture system, which is manufactured and sold by Becton, Dickinson and Company. U.S. Patent No. 5,817,508, entitled “Blood Culture Apparatus having an Auto-Unloading and Sorting Device,” describes a prior art blood culture apparatus, and is incorporated herein byreference. Additional descriptions of blood culture apparatus are provided in U.S. Patent No. 5,516,6)92, entitled “Compact Blood Culture Apparatus,” and U.S. Patent No. 5,498,543, entitled “Sub-Compact Blood Culture Apparatus,” both of which are incorporated herein by reference.

[0005] Even when using existing automated apparatus, it can still be laborious and time consuming for operators to process blood culture bottles. For example, operators may need to individually load and unload blood culture bottles from an automated blood culture apparatus. Operators may also need to manually separate blood culture bottles that tested positive from blood culture bottles that tested negative, discard the negative blood culture bottles into waste receptacles, and prepare the positive blood culture bottles for additional microbiological workup. Such lab environments fail to realize maximum efficiency due to delays in manual handling and processing of the samples. These delays can cause unnecessary delays in diagnosing and treating patients. Moreover, operator errors (e.g., human errors) may result when the operators are tired, distracted, or otherwise unfocused and can lead to processing errors, which may result in an incorrect diagnosis, a late diagnosis, and lost or ruined samples. Such errors can potentially adversely affect patients and waste resources.

[0006] Thus, there is a need in the art for a lab automation system that is capable of receiving batches of blood culture bottles, separating positive and negative blood culture bottles, and discarding negative blood culture bottles in a safe, secure, and consistent manner at all times of the day with minimal intervention from a small number of lab operators.BRIEF SUMMARY OF THE INVENTION

[0007] The present disclosure provides several improvements to optical Time-of-Flight (ToF) object presence detection techniques, resulting in an improved object presence detection sensor design. In some implementations, a spatial filter is coupled to an optical ToF sensor to reduce the angle of the illumination cone produced by an emitter of the ToF sensor and / or the FOV of the detector of the ToF sensor. In some implementations, the spatial filter may include a tube and / or a passage aligned with the emitter and / or the detector of the ToF sensor. In some implementations, the spatial filter may be a Micro Honeycomb Spatial Filter (MHSF) or a Micro Spatial Filter (MSF). In some implementations, the spatial filter may allow the ToF sensor to reliably detect objects, such as blood culture bottles.

[0008] One aspect of the present disclosure relates to a system comprising an optical time- of- flight sensor and a spatial filter. The optical time-of-flight sensor comprises an emitter fortransmitting an optical signal towards an object and a detector for receiving an optical signal reflected off the object. The spatial filter comprises a first passage that is aligned with (a) the emitter such that the transmitted optical signal passes through the first passage before contacting the object or (b) the detector such that the received optical signal passes through the first passage before contacting the detector. The spatial filter also reduces an angle of (a) an illumination cone produced by the emitter or (b) a field of view of the detector.

[0009] In some implementations, the first passage is aligned with the emitter such that the transmitted optical signal passes through the first passage before contacting the object, and the spatial filter reduces the angle oft.be illumination cone produced by the emitter. In some such implementations, the spatial filter further comprises a second passage that is aligned wdth the detector such that the received optical signal passes through the second passage before contacting the detector, and the spatial filter reduces the angle of the field of view of the detector. In some such implementations, the spatial filter farther comprises a tube with an interior passage comprising the first or second passage.

[0010] In some implementations, the first passage is aligned with the detector such that the received optical signal passes through the first passage before contacting the detector, and the spatial filter reduces the angle of the field of view of the detector.

[0011] In some implementations, the spatial filter reduces the angle of the illumination cone from approximately 25° to approximately 10°. In some implementations, the spatial filter farther comprises a recess configured to (a) receive the optical time-of-flight sensor and (b) align the first passage with at least one of the emitter or the detector. In some implementations, the spatial filter is a micro honeycomb spatial filter.

[0012] In some implementations, the spatial filter is a micro spatial filter. In some such implementations, the micro spatial filter is printed using micro digital light processing. In some such implementations, the micro spatial filter is printed with Vero Ultra Black photopolymer ink. In some such implementations, the micro spatial filter is printed on a thin-release film printing substrate.

[0013] In some implementations, the system further comprises a compartment configured to (a) receive individual untested sample containers or a rack of untested sample containers or (b) output individual positive sample containers or a rack of positive sample containers, wherein the optical time-of-flight sensor is coupled to a ceiling of the compartment and configured to detect the presence or absence of a sample container. In some implementations,the compartment comprises a liner with one or more sections, wherein each of the one or more sections comprises a plurality of receptacles configured to accept sample containers directly and a pair of recesses configured to accept a rack of sample containers. In some implementations, the sample containers are blood culture bottles.

[0014] Another aspect of the present disclosure relates to a spatial filter comprising a first passage, wherein the spatial filter is configured to couple with an optical time-of-flight sensor comprising (a) an emitter for transmitting an optical signal towards an object and (b) a detector for receiving an optical signal reflected off the object, wherein the first passage is configured to align with (a) the emitter such that the transmitted optical signal passes through the first passage before contacting the object or (b) the detector such that the received optical signal passes through the first passage before contacting the detector, and wherein the spatial filter is configured to reduce an angle of (a) an illumination cone produced by the emitter or (b) a field of view of the detector.

[0015] In some implementations, the first passage is configured to align w ith the emitter such that the transmitted optical signal passes through the first passage before contacting the object, and the spatial filter is configured to reduce the angle of the illumination cone produced by the emitter. In some such implementations, the spatial filter further comprises a second passage that is configured to align with the detector such that the received optical signal passes through the second passage before contacting the detector, and the spatial filter is configured to reduce the angle of the field of view of the detector.

[0016] In some implementations, the first passage is configured to align wuth the detector such that the received optical signal passes through the first passage before contacting the detector, and wherein tire spatial filter is configured to reduce the angle of the field of viewrof the detector.

[0017] In some implementations, the spatial filter further comprises a recess configured to (a) receive the optical time-of-flight sensor and (b) align the first passage with at least one of the emitter or the detector.BRIEF DESCRIPTION OF DRAWINGS

[0018] FIG . I A illustrates an automated system for processing a plurality of sample containers.

[0019] FIG. IB illustrates a module of the automated system illustrated in FIG. 1A.

[0020] FIGS. 2A-2D are perspective views of the module of FIG. IB without a housing. This exposes aspects of, for example, a user interface subsystem, an imaging subsystem, a waste management subsystem, and a robotic subsystem.

[0021] FIG. 2E is a close-up view of an electronics bay.

[0022] FIGS. 3A-3C are perspective views of a user interface subsystem, which includes compartments for receiving and outputting sample containers.

[0023] FIGS. 4A and 4B are perspective views of a liner, a rack, and sensors.

[0024] FIGS. 4C-4I illustrate different views of the rack of FIGS. 4A and 4B.

[0025] FIG. 5 illustrates an optical Time-of-Flight (ToF) sensor.

[0026] FIG. 6 illustrates a compartment for receiving and outputting sample containers.

[0027] FIG. 7 is a plot of the measurements obtained using optical ToF sensors that are positioned in a ceiling of the compartment of FIG. 6.

[0028] FIG. 8A illustrates an optical ToF sensor above a sample container.

[0029] FIG. 8B is a graph of the measurements obtained with the sensor of FIG. 8 A.

[0030] FIG. 9 illustrates an optical ToF sensor and a spatial filter.

[0031] FIG. 10 illustrates an optical ToF sensor and a spatial filter.

[0032] FIG. 11 illustrates an optical ToF sensor and a spatial filter.

[0033] FIGS. 12A-12D illustrate an optical ToF sensor and / or a spatial filter.

[0034] FIG. 13 is a plot of the measurements obtained using the sensor of FIGS. 12A-12D when it is positioned in a ceiling of the compartment of FIG. 6.

[0035] FIGS. 14A illustrates a compartment for receiving and outputting sample containers, wherein the sample containers are positioned in a liner.

[0036] FIGS. 14B illustrates the compartment of FIG. 14A, wherein tire sample containers are positioned in racks.

[0037] FIG. 14C is a plot ofthe measurements obtained using the sensor of FIGS. 12A-12D when it is positioned in a ceiling of the compartment of FIGS. 14A and 14B.DETAILED DESCRIPTION

[0038] Aspects of the present disclosure are described in detail with reference to the drawing figures wherein like reference numerals identify similar or identical elements. It is to be understood that the disclosed implementations are merely examples of the disclosure, which may be embodied in various forms. Well-known functions or constructions are not described in detail to avoid obscuring the present disclosure in unnecessary detail. Therefore, specificstructural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present disclosure in virtually any appropriately detailed structure.

[0039] FIG. 1 A illustrates an automated system 100 for processing a plurality of sample containers (e.g., blood culture bottles) that includes modules 101 and 102. Module 101 is a sample handling module that is configured to receive sample containers, scan sample containers, transfer sample containers to and from module 102, dispose of sample containers that test negative, and provide sample containers that test positive at an output. As shown, module 101 includes display 310, output chutes 320, compartments 330 and 340, and door 110, which may provide access to a waste receptacle. Examples of a sample handling module, such as module 101, are described in International Application No. PCT / US2O23 / O28O36, filed July 18, 2023, entitled “Systems and Methods for Sample Handling,” which is incorporated herein by reference.

[0040] Module 102 is an incubation and measurement module that is configured to determine whether the sample containers are contaminated with or infected by microorganisms. As shown, module 102 includes doors 121 and 122, which may provide access to drums that hold the sample containers during the incubation and measurement processes. Examples of an incubation and measurement module, such as module 102, are described in International Publication No. WO / 2021 / 026272 Al, entitled “High Density Bottle Drum for Storage, Agitation and Reading of Blood Culture Bottles and Methods of Storing,” which is incorporated herein by reference.

[0041] In some implementations, module 102 may include a high-density drum. High density, as used herein is a description of drum configurations that allow sample containers (e.g. , blood culture bottles) to be placed closer to each other to allow a greater number of sample containers to be fitted into the drum compared to the prior art. In some implementations, module 102 may be configured to align the sample containers with a limited number of reader stations. That is, the number of reader stations is less than the number of sample container receptacles in the drum. In some implementations, the drum may be operated by a direct drive motor that can cause accelerated and decelerated drum movement (e.g., a rocking movement, intermittent rotation, etc.). Tn some implementations, a heater and blower may be provided in the drum housing. The heater and blower circulate warm air around the drum. In some implementations, the heater and blower may be configured to keep the temperature of thecon tents of all sample con tainers in the drum within a predetermined narrow range of a specific target temperature. The predetermined narrow range may, for example, be ± 1 ,5°C of tire target temperature. The specific target temperature may be in the range of 30°C to 40°C. Optionally, the target temperature may be 36.5OC ± 0.5°C. Greater temperature uniformity may permit an increase in set point as there is less risk of “over-heating” samples. A greater temperature uniformity at higher temperature will therefore permit a faster time to detection of positive samples. The motor may permit the drum to be positioned such that the user or the automated apparatus can access any sample container carried by the drum. When a sample container is determined to be positive for microbial growth, a workflow may be activated to retrieve that sample container from module 102.

[0042] FIG. IB illustrates module 101 after it has been separated from module 102. As shown, module 101 includes housing 130, which includes front panel 131. top panel 132, and side panel 133. Side panel 133 includes sliding doors 141 and 142. Doors 141 and 142 may be used to access the drums in module 102. For example, door 141 may be used to access a first drum and door 142 may be used to access a second drum. Doors 141 and 142 may also be used to isolate the environmental conditions (e.g., temperature conditions) within module 101 from the environmental conditions within module 102. In some implementations, module 101 may also include heating and''or cooling components (see, e.g., fan 220 of FIGS. 2A-2D) to regulate the environmental conditions within module 101.

[0043] FIGS. 2A-2D provide perspective views of module 101 without housing 130. As shown, module 101 includes frame 210, fan 220, electronics bay 230, display 310, output chutes 320, compartments 330 and 340, imaging subsystem 240, waste management subsystem 250, and robotic subsystem 260. Sample containers (e.g., blood culture bottles) may be received by module 101 in compartments 330 and 340. Robotic subsystem 260 may be configured to transfer sample containers to and / or from module 102, output chutes 320, compartments 330 and 340, imaging subsystem 240, and / or waste management subsystem 250. For example, robotic subsystem 260 may be configured to transfer sample containers to one or more of the drums in module 102 (e.g. , through one or more of doors 141 and 142). As another example, robotic subsystem 260 may be configured to transfer sample containers to and / or from compartments 330 and 340. As yet another example, robotic subsystem 260 may be configured to transfer sample containers to output chutes 320 for retrieval by a user. As yet another example, robotic subsystem 260 may be configured to transfer sample containers toimaging subsystem 240 for scanning. As yet another example, robotic subsystem 260 may be configured to dispose of sample containers in waste management subsystem 250.{0044] Robotic subsystem 260 may also be configured to automatically distribute and / or redistribute sample containers around the circumference of one or more drums in module 102 to distribute the sample containers as desired. For example, robotic subsystem 260 may be configured to move sample containers in module 102 to a specific area of a drum (e.g. , an area that can be viewed entirely when door 121 122. 141 or 142 is open). This may enable a user to quickly unload those sample containers without having to repeatedly open and close doors 121 and / or 122 and wait for one or more drams in module 102 to rotate. Similarly, this may enable robotic subsystem 260 to quickly retrieve those sample containers without having to repeatedly open and close doors 141 and 142 and wait for one or more drums in module 102 to rotate. As another example, robotic subsystem 260 may be configured to distribute and / or redistribute sample containers around the circumference of one or more drums in module 102 to balance the dram load (e.g., weight load and / or thermal load). In implementations in which incubation and measurement modules (e.g., module 102) are coupled to both sides of module 101, robotic subsystem 260 may also be configured to automatically distribute and / or redistribute sample containers between the incubation and measurement modules.

[0045] Imaging subsystem 240 may be configured to scan sample containers for label information and / or obtain image information from which the presence or absence of foam, fill level and / or other information regarding the contents of sample containers may be derived. In some implementations, robotic subsystem 260 may deliver sample containers to imaging subsystem 240 both before and after those sample containers have been incubated and measured in module 102. By scanning sample containers a second time before they are placed in compartments 330 and / or 340 for retrieval by a user and / or placed in waste receptacle 610 of waste management subsystem 250 for disposal, system 100 can provide increased confidence in the chain of custody of the sample containers. During operation, system 100 may experience conditions, such as power failure and / or unexpected user interactions, that create opportunities to lose the chain of custody for one or more sample containers.

[0046] Waste management subsystem 250 may include a waste receptacle and a chute. During operation, robotic subsystem 260 may drop negative sample containers into the waste receptacle through the chute. This alleviates the user from the workload associated withnegative sample containers, which is usually -90% of the sample containers subjected to testing for the presence of biologically active agents.

[0047] FIG. 2E is a close-up view of electronics bay 230. As shown, computer 231 , power supply 232, power distribution board 233, back-up power supply 234, and network sw itch 235 are positioned in electronics bay 230. Some components of robotic subsystem 260 may also be fully or partially positioned in electronics bay 230. Computer 231, pow'er supply 232, pow'er distribution board 233, back-up power supply 234, and / or network switch 235 may include one or more processors, one or more application specific integrated circuits (ASICs), and'or other similar components. These components may also include a memory' medium, such as a harddrive, memory card, ROM, RAM, DVD, CD-ROM, write-capable, and / or read-only memory, that is capable of storing information. Computer 231 may be communicatively coupled with one or more of the subsystems of module 101. For example, computer 231 may be communicatively coupled to user interface subsystem 300 (see FIGS. 3A-3C), imaging subsystem 240, w-asle management subsystem 250, anchor robotic subsystem 260. In some implementations, computer 231 may transmit commands to each of these subsystems and receive measurement data from these subsystems. For example, computer 231 may be configured to control the movements of robotic subsystem 260 and receive measurement data from one or more components of robotic subsystem 260 (e.g., controllers and'or sensors). Computer 231 may also be configured to transmit a graphical user interface (GUI), user prompts, user instructions, alerts, system settings, and'or other information to a display.

[0048] Power supply 232 may be coupled to an external power source (e.g., an alternating current (AC) wall outlet). Power distribution board 233 may be coupled to pow'er supply 232 and configured to distribute pow'er from pow'er supply 232 to one or more of the subsystems of module 101. Network switch 235 may be communicatively coupled to computer 231 and one or more external devices (e.g., module 102). In some implementations, computer 231 may transmit and receive data using standard communications protocols, such as Inter-Integrated Circuit (I2C), Serial Peripheral Interface (SPI), Controller Area Network (CAN), Universal Asynchronous Reception and Transmission (UART), Ethernet, or Uni versa! Serial Bus (USB), or custom communications protocols. In some implementations, computer 231 may wdrelessly transmit and receive data using standard communications protocols, such as Bluetooth, WiFi, ZigBee, Z-Wave, NEC Infrared (IR), Code Division Multiple Access (CDMA), Global System for Mobile Communications (GSM), or Long-Term Evolution (LTE), or customcommunications protocols. For example, computer 231 may communicate with one or more internal devices using the CAN protocol. As another example, computer may communicate with one or more external devices using the Ethernet protocol. In such implementations, network switch 235 may be an Ethernet switch.

[0049] FIG. 3A provides a perspective view of a front side of user interface subsystem 300. As shown, user interface subsystem 300 includes display 310, output chutes 320, compartments 330 and 340, doors 351 and 352, reader 360, computer 370, and liners 401 and 402. FIGS. 3B and 3C provide perspective views of a back side of user interface subsystem 300. However, in FIG. 3C, door 352 has been removed to reveal compartment 330 and liner 401. Portions of imaging subsystem 240 are also shown in FIGS. 3A-3C. User interface subsystem 300 may be hingedly and / or slidingly connected to frame 210, such that they can be serviced by a technician without moving module 101.

[0050] Display 310 may be a touchscreen, monitor, LCD panel, or the like that is configured to display a graphical user interface (GUI), user prompts, user instructions, alerts, system settings, and / or other information that may be relevant to a user. For example, after a batch of sample containers has been received by module 101 and successfully scanned (e.g., by imaging subsystem 240), display 310 may notify the user that the sample containers have been accepted and are being processed. As another example, if the label on a sample container cannot be read, display 310 may display an alert on display 310 that notifies a user of the problem. As yet another example, after a sample container has been deposited into output chutes 320 by robotic subsystem 260, display 310 may be configured to display an arrow above the corresponding chute. Other types of icons, such as a line or a bottle shape, can be used instead of an arrow. In some implementations, the icon may be colored and / or flashing to draw the user’s attention. In some implementations, the icon can be pressed to reveal information about the corresponding sample container, such as accession number, sequence number, container type, fill volume, and / or images of the sample container.

[0051] In implementations where display 310 is a touchscreen, it may also be configured to receive inputs from the user. In some implementations, inputs from the user may be received from another device that is part of module 101 (e.g., a microphone and / or a keypad) or that is in communication with module 101 (e.g. , a mouse and / or keyboard). Regardless of how the user input is received, display 310 may be utilized to implement a load routine and an unload routine. During the load routine, display 310 may ask the user to identify the contents of thesample containers (e.g., controls, empty sample containers, or samples). After the sample containers have been loaded into module 101 , they may be digitally tagged with the information provided by the user. During the unload routine, display 310 may request the user to input which sample containers the user would like to unload and / or where the sample containers should be placed (e.g., output chutes 320, compartment 330, or compartment 340).

[0052] Output chutes 320 may be used to deliver individual sample containers to a user for retrieval. For example, after a sample is determined to positive in module 102, a user may need to retrieve that sample container for additional microbiological workup. The sample container may be retrieved from module 102 and output from module 101. As shown, there are five output chutes 320. However, in other implementations, module 101 may include more or less output chutes. In some implementations, output chutes 320 may be structured to mitigate the noise made when a bottle is dropped down a chute. In some implementations, output chutes 320 may be constructed with a noise-absorbing material to mitigate the noise made when a bottle is dropped down a chute.

[0053] In some implementations, indicator lights (not shown) may be provided near one or more of output chutes 320 (e.g., above or below). Each one of the indicator lights may be configured to illuminate when a sample container is positioned in a particular chute (e.g., the chute below the corresponding light) or when a sample container is positioned in any one of output chutes 320. In some implementations, the indicator lights may be different colors, change colors, and / or flash. Furthermore, in some implementations, the indicator lights may be configured to behave differently depending on the type of sample container positioned in output chutes 320. For example, the indicator lights may illuminate as one color when a sample container is positive (e.g., red) and the indicator lights may illuminate as another color when a sample container is negative (e.g., green). In some implementations, the information regarding sample status (e.g., positive or negative) may be transmitted from a sample status indicator in module 102. The status of a sample container may be associated with a barcode on the sample container and that barcode information may be read when the sample container is retrieved from module 102 to determine the output chute, tray, or receptable in w'hich to place the retrieved sample container.

[0054] In some implementations, output chutes 320 may include one or more sensors (not shown) that are configured to detect when a sample container has been deposited into output chutes 320. This detection may be used to trigger the illumination of the indicator lights. It mayalso be used to provide feedback to robotic subsystem 260. Such feedback may advantageously prevent robotic subsystem 260 from depositing another sample container down the same chute and causing a crash andtor contamination. In some implementations, the one or more sensors may be positioned at the bottoms of each of output chutes 320. In some implementations, the one or more sensors may be touch sensors, optical sensors, and / or ultrasonic sensors.

[0055] Compartments 330 and 340 may be used for both input and output purposes. For example, while a user is loading compartment 330 with untested sample containers, robotic subsystem 260 may be depositing sample containers in compartment 340 for retrieval by a user. Similarly, while a user is loading compartment 340 with untested sample containers, robotic subsystem 260 may be depositing sample containers in compartment 330 for retrieval by a user. Alternatively, compartments 330 and 340 may be simultaneously utilized as an input area or an output area. For example, a user may load untested sample containers into both of compartments 330 and 340. As another example, robotic subsystem 260 may deposit sample containers into both of compartments 330 and 340 for retrieval by a user. As a result, in the particular implementation of FIGS. 3A-3C, a user can load or unload up to 60 sample containers at the same time. In other implementations, module 101 may include more or less compartments. For example, a third compartment structured like compartments 330 and 340 may be added to module 101 to increase the number of sample containers that can be loaded and unloaded at a single time to 90.

[0056] In some implementations, compartments 330 and 340 may be utilized as the primary' output areas and output chutes 320 may be utilized as the secondary output area. For example, in such implementations, batches of sample containers that tested positive may be deposited into compartments 330 and / or 340 by robotic subsystem 260. Having a designated area where batches of positives are presented (separate from negatives) saves time and reduces the risk of user error (e.g., due to inaccurate sorting). Furthermore, in such implementations, output chutes 320 may be utilized for outputting individual sample containers, sample containers requiring additional information and / or sample containers requiring system error resolution. For example, when imaging subsystem 240 is unable to read a barcode label on a sample container, robotic subsystem 260 may deposit that sample container into one of output chutes 320. This allows a user to resolve the problem by, for example, removing obstructions from the label or applying a new bar code label. In other implementations, compartments 330and / or 340 may be utilized as the secondary output areas and output chutes 320 may be utilized as the primary output area.{0057] In some implementations, a user can designate whether one or more of output chutes 320, compartment 330, and / or compartment 340 are utilized as the primary and / or secondary output areas. For example, display 310 can be utilized to access system settings that allow a user to designate where untested sample containers are received by module 101 and where sample containers are deposited by robotic subsystem 260 for retrieval by a user. Through these system settings, a user may also be able to specify whether the sample containers are output into a removeable rack. In such implementati ons, if no rack is detected, display 310 may alert the user.

[0058] The input and output areas described above (e.g., output chutes 320 and compartments 330 and 340) are particularly advantageous due to their flexibility. For example, since compartments 330 and 340 can be utilized as input or output areas, a large number of sample containers can be loaded or unloaded at a single time. Furthermore, some laboratories may prefer to use compartments 330 and 340 as the primary output area and others may prefer to use output chutes 320 as the primary output area. For example, sample containers may make noise as they descend output chutes 320, which may convey the impression of poor quality. Placing sample containers in compartments 330 and / or 340 for retrieval avoids such noises. Additionally, when placed in racks, large numbers of sample containers can be quickly unloaded by a user from compartments 330 and / or 340.

[0059] As shown in FIG. 3A, compartment 330 includes liner 401 and compartment 340 includes liner 402. In some implementations, one or both of liners 401 and 402 may' be a piece of molded plastic that has cylindrically shaped receptacles designed to accept sample containers (e.g., blood culture bottles) directly. In some implementations, one or more receptables may be structured to prevent a sample container from falling over after being placed in a receptable. One or both of liners 401 and 402 may also include recesses designed to accept racks of sample containers. In some implementations, liners 401 and / or 402 may include acrylonitrile-butadiene-styrene (ABS), polypropylene (PP), polystyrene (PS), another type of plastic, and / or a mix thereof.

[0060] Liners 401 and 402 may advantageously enable a user to load a variable number of sample containers into module 101. Liners 401 and 402 may also advantageously enable a user to load individual sample containers or racks of sample containers into module 101. Having aflexible input area such as this allows users to maintain the same workflow for loading small (e.g., 1-2 sample containers), medium, and large (e.g., 20+ sample containers) batches of sample containers. There are separate advantages to loading sample containers individually and loading sample containers in racks. For example, racks provide a visual cue for users to transfer sample containers to and / or from module 101. This may allow a laboratory to develop Standard Operating Procedures (SOP) around batch loading. Furthermore, it is quicker to load a plurality' of sample containers into module 101 by simply placing a rack in module 101, as opposed to individually placing each sample container in module 101. Moreover, studies have shown that racks add a layer of safety' when transporting sample containers within a laboratory. However, studies have also shown that users often forget to reload racks into laboratory instruments. Additionally, not all laboratories prefer to use racks. Many do not prefer the usage of racks for reasons including extra time spent managing racks, labelling them, handling the loss, damage and reordering of racks, and cleaning of the racks. Therefore, having a system that accepts individual sample containers or racks of sample containers is particularly advantageous.

[0061] In some implementations, liner 401 may be removably coupled to a first drawer (not shown) and / or liner 402 may be removably coupled to a second drawer (not shown). The one or more drawers may include a flat shelf that partially or fully slides out of module 101 using drawer ball-bearing slide rails or another similar mechanism. This is advantageous as it allows the user to see the cylindrical recesses and allows the sample containers to be placed from above, which enhances the usability and ergonomics of loading and unloading sample containers. In some implementations, one or both of liners 401 and 402 may be removed from a drawer by a user by use of a thumb screw, a latch, or other similar fastener. After a liner has been removed, it can be easily cleaned (e.g., in a bleach solution soaking tub). Furthermore, while a liner is being cleaned, another liner can be placed in module 101 to limit instrument down-time. In some implementations, one or more receptacles in liners 401 and / or 402 may include a hole at the bottom of the receptacle. When liners 401 and / or 402 are removed from module 101, these holes may allow cleaning fluids to drain through. Furthermore, when liners 401 and / or 402 are positioned in module 101 , these holes may allow one or more sensors to detect the presence or absence of sample containers. In some implementations, the one or more sensors may be touch sensors, optical sensors, and-'or ultrasonic sensors.

[0062] In some implementations, compartments 330 and / or 340 may' include indicator lights (not shown). The indicator lights may be positioned above liners 401 and / or 402. Theseindicator lights may be used to signal to a user how compartments 330 and / or 340 are being utilized. For example, when compartment 330 is being utilized as an input area, one or more indicator lights may illuminate compartment 330 with a first color (e.g., blue or green), and when compartment 330 is being utilized as an output area, the one or more indicator lights may illuminate compartment 330 with a second color (e.g. , red). Similarly, when compartment 340 is being utilized as an input area, one or more indicator lights may illuminate compartment 340 with a first color (e.g., blue or green), and when compartment 340 is being utilized as an output area, the one or more indicator lights may illuminate compartment 340 with a second color (e.g., red). The one or more indicator lights in compartments 330 and / or 340 may also be used indicate whether a batch of sample containers is ready for retrieval. For example, while robotic subsystem 260 is depositing sample containers into one of compartments 330 and 340, the compartment may be illuminated with a first color (e.g., red), and when the batch of sample containers is ready for retrieval, the compartment may be illuminated with a second color (e.g., blue or green), hi some implementations the indicator lights may flash instead of changing colors.

[0063] As shown in FIGS. 3A-3C, door 351 may be positioned on the front side of user interface subsystem 300, and door 352 may be positioned on the back side of user interface subsystem 300. Doors 351 and 352 are vertical sliding doors configured to be raised and lowered to expose either one of compartments 330 and 340. For example, when doors 351 and 352 are in a raised position, compartment 330 is sealed and compartment 340 is exposed. Similarly, when doors 351 and 352 are in a lowered position, compartment 340 is sealed and compartment 330 is exposed. In some implementations, doors 351 and 352 may be configured to maintain positions opposite one another. For example, when door 351 is in a raised position, door 352 is in a lowered position. Similarly, when door 351 is in a lowered position, door 352 is in a raised position. This may prevent a user from mixing untested sample containers with sample containers that have tested positive. For example, while robotic subsystem 260 is depositing positive sample containers into compartment 330, door 351 may be in a raised position to prevent a user from placing untested sample containers in compartment 330. Furthermore, door 352 may help prevent sample containers from falling into module 101 (e.g., onto support structure 641 of waste management subsystem 250) while a user loads untested sample containers into one of compartments 330 and 340.

[0064] In some implementations, one or both of doors 351 and 352 may be constructed with a transparent material, such as plastic or glass. A transparent material advantageously permits a user to observe the processing of the sample containers, which may provide increased confidence in the system. For example, a transparent door allows users to see the sample containers being loaded and unloaded, which increases their overall understanding of how the system works, their visibility to potential jams / errors, and potentially their overall trust in the instrument. As shown, door 351 is constructed with a transparent material and door 352 is constructed with an opaque material. However, in other implementations, both of doors 351 and 352 may be constructed with a transparent material. Furthermore, in other implementations, both of doors 351 and 352 may be constructed with an opaque material.

[0065] In other implementations, doors 351 and 352 may be replaced with one or more swinging doors. For example, door 351 may be replaced with a pair of swinging doors, one of which is configured to seal compartment 330 and one of which is configured to seal compartment 340. In such implementations, one or both of the swinging doors may be locked to prevent a user from accessing the corresponding compartment. For example, while robotic subsystem 260 is depositing positive sample containers into compartment 330, the swinging door positioned in front of compartment 330 may be locked. Similarly, while robotic subsystem 260 is depositing positive sample containers into compartment 340, the swinging door positioned in front of compartment 340 may be locked.

[0066] As shown in FIG. 3A, reader 360 may be configured to read barcode labels, RFID tags, and-' or other types of identifiers on sample containers and / or user identification cards. For example, a user can scan a sample container using reader 360 to lookup information for that sample container (e.g., a sequence number or accession number). In some implementations, the information may be provided on display 310. In some implementations, after scanning a sample container with reader 360, a user can manually load the sample container into an incubation and measurement module, such as module 102. In some implementations, a user can place his or her employee badge or other unique identification card in proximity to the reader 360 to initiate an automatic login. To protect patient information and comply with cyber security regulations, a user may need to login to perform certain actions, such viewing test results and obtaining positive sample containers. In some implementations, a user can place his or her employee badge or other unique identification card in proximity to the reader 360 to automatically adjust one or more system settings. For example, module 101 may store userpreferences regarding where sample containers are deposited for retrieval and automatically adjust tire system settings to those preferences after the user scans his or her unique identification card.

[0067] In some implementations, separate readers may be provided for reading identifiers on sample containers and for reading user identification cards. In some implementations, the one or more readers may use different scanning technologies. For example, an optical bar-code reader could be used to scan the labels on sample containers and a radio frequency identification (RFID) reader could be used to scan user identification cards. In some implementations, a user may also login via other methods, such as a username and password, a passphrase, a PIN, and''or a picture password. In some implementations, a user may also login via a biometric alternative, such as voice, facial, retinal, and / or fingerprint recognition.

[0068] As shown in FIG. 3A, computer 370 may include one or more processors, one or more application specific integrated circuits (ASICs), and / or other similar components. Computer 370 may also include a memory medium, such as a hard-drive, memory card, ROM, RAM, DVD, CD-ROM, write-capable, and / or read-only memory, that is capable of storing information. Computer 370 may be communicatively coupled with one or more of the subsystems of module 101. For example, computer 370 may be communicatively coupled to one or more components of electronics bay 230 (e.g., computer 231), user interface subsystem 300, imaging subsystem 240, waste management subsystem 250, and / or robotic subsystem 260. In some implementations, computer 370 may receive commands from one or more of these subsystems. In some implementations, computer 370 may transmit commands to one or more of these subsystems and receive measurement data from one or more of these subsystems. For example, computer 370 may be configured to control the movements of robotic subsystem 260 and receive measurement data from one or more components of robotic subsystem 260 (c.g, controllers and / or sensors). Computer 370 may also be configured to transmit a graphical user interface (GUI), user prompts, user instructions, alerts, system settings, and / or other information to display 310 for display.

[0069] FIGS. 4A and 4B provide perspective views of liner 401. As shown, liner 401 includes sections 411-413. Sensors 441-443 extend through sections 411-413, respectively, and may be configured to detect whether a rack is present. In some implementations, sensors 441 - 443 may be touch sensors, optical sensors, and / or ultrasonic sensors. Section 41 1 includes receptacles 421 designed to accept sample containers (e.g., blood culture bottles) directly andrecesses (not shown) designed to accept racks of sample containers, such as rack 450. FIGS. 4C-4I illustrate different views of rack 450. More specifically, FIG. 4C is a perspective view of rack 450, FIG. 4D is a front elevation view thereof, FIG. 4E is a back elevation view thereof, FIG. 4F is a right-side elevation view thereof, FIG. 4G is a left-side elevation view thereof, FIG. 4H is a top-down view thereof, and FIG. 41 is a bottom-up view' thereof.

[0070] As shown in FIGS. 4A and 4B, a single sample container 461 is positioned in one of the receptacles 451 of rack 450. Section 412 includes receptacles 422 designed to accept sample containers directly and recesses 432 designed to accept racks of sample containers. Section 413 includes receptacles 423 designed to accept sample containers directly, such as sample container 462, and recesses 433 designed to accept racks of sample containers. As shown, receptacles 421 -423 and / or 451 may include a cylindrical chamfer feature to facilitate the insertion of a sample container into the corresponding receptacle. One or more of receptacles 421-423 and / or 451 may also include a hole (<?.g., holes 452 in FIGS. 4C, 4H, and 41) at the bottom of the receptacle. During cleaning, these holes may allow cleaning fluids to drain through. As shown, receptacles 421-423 and / or 451 may have bottoms wdth rounded edges to accommodate rocker bottles. A rocker bottle has a convex bottom due to pressure build up or heat in manufacturing. Inspection and controls are in place to prevent this, but some bottles make it through with up to, for example, a 1 ,5mm convex shape.

[0071] As shown in FIGS. 4A and 4B, each one of sections 411-413 can hold up to ten sample containers in the corresponding receptacles. Rack 450 can also hold up to ten sample containers in receptacles 451. However, in other implementations, sections 41 1-413 and / or rack 450 may be configured to hold more or less sample containers. Similarly, in other implementations, liner 401 may include more or less sections of receptacles. For example, liner 401 may only include two sections, each of which can hold up to fifteen sample containers. In such implementations, rack 450 may also be reconfigured to hold up to fifteen sample containers.

[0072] As shown in FIGS. 4A and 4B, receptacles 421-423 and 451 are configured to accept bottles having a particular diameter. For example, receptacles 421-423 and 451 may be configured to accept specific types of culture bottles, such as tire BD BACTEC™ culture bottles, which are manufactured and sold by Becton, Dickinson and Company. However, in other implementations, receptacles 421-423 and 451 may be shaped differently and configured to hold different types of sample containers. Furthermore, in some implementations,receptacles 421-423 and 451 may be configured to accept a range of sample containers with differing diameters and / or heights. For example, one or more of receptacles 421-423 and 451 may have lower and upper portions with different diameters. The lower portion may, for example, have a narrow diameter for accepting sample containers with a similarly narrow diameter. Furthermore, the upper portion may, for example, have a wide diameter for accepting sample containers with a similarly wide diameter.

[0073] In some implementations, liner 401 may include one or more features for calibrating robotic subsystem 260. For example, liner 401 may include notches 471 and 472. In some implementations, a pin (not shown?) may be temporarily or permanently added to robotic subsystem 260. In some implementations, the pin may remain attached to robotic subsystem 260 during the processing of sample containers. The pin may be sized to fit within notches 471 and 472. After engaging one of notches 471 and 472 with the pin, the positions of one or more components of robotic subsystem 260 may be saved in memory and used as a point of reference for future movements of robotic subsystem 260.

[0074] As best seen in FIGS. 4C-4I, rack 450 can be advantageously picked up with one hand by a user. For example, a user may position his or her thumb in one of recesses 453 while simultaneously resting the tips of his or her fingers along one of slanted surfaces 454. The user may then slide his or her fingers along the slanted surface 454 until they contact bottom surface 455 of rack 450. Once in this position, the user can securely lift rack 450. Advantageously, the symmetrical shape of recesses 453 and slanted surfaces 454 allows a user to lift rack 450 with his or her right hand or left hand.

[0075] In some implementations, one or more optical Time-of-Flight (ToF) sensors may be positioned in automated system 100 for the detection of objects. For example, ToF sensors may be used to detect sample containers (e.g., blood culture bottles). In some such implementations, the ToF sensors may be positioned within one or more of output chutes 320, compartment 330, compartment 340, imaging subsystem 240, waste management subsystem 250, and / or robotic subsystem 260. As another example, ToF sensors may be used to detect the position of robotic subsystem 260. In some such implementations, the ToF sensors may be included in robotic subsystem 260. In other such implementations, the ToF sensors may be positioned within housing 130 and / or another subsystem of module 101.

[0076] FIG. 5 illustrates a ToF sensor 510. As shown, ToF sensor 510 includes emitter 560 and detector 580. One example of a comparable ToF sensor is the VL6180X sensor, which ismanufactured by STMicroelectronics NV. This sensor is described in STMicroelectronics NV, VL6180X Datasheet: Proximity and ambient light sensing (ALS) module (2016) (available at https: / / www.st.com / en / imaguig-and-photonics-solutions / vl6180x.html), which is incorporated herein by reference. In some implementations, emitter 560 includes one or more vertical cavity surface-emitting lasers (VCSELs). In some implementations, an aperture of emitter 560 may have a diameter of approximately 0.5 mm. In some implementations, emitter 560 is pulsed at approximately 100 MHz with approximately a 33% duty cycle. In some implementations, emitter 560 may transmit light at approximately 850 nm. In some implementations, divergent light emitted from emitter 560 may form an illumination cone that is 25° + / - 5° (e.g., defined by 1 / e2of the peak intensity ). In some implementations, detector 580 includes one or more single-photon avalanche diodes (SPADs). In some implementations, an aperture of detector 580 may have a diameter of approximately 0.3 mm.

[0077] During operation, a pulse of light is transmitted from emitter 560 of ToF sensor 510 towards a target object. The light reflected from the target object is then received by detector 580. By measuring how long it takes the light pulse to travel to and from the target object, the distance between ToF sensor 510 and the target object can be inferred. For example, the distance can be calculated as follows:where d is the inferred distance between ToF sensor 510 and the target object, c is the speed of light, and t is the round-trip time for the light to travel.

[0078] An object can be detected with ToF sensor 510 by, for example, setting a distance threshold. When the inferred distance between ToF sensor 510 and a nearby object is below the distance threshold, the nearby object may be detected, resulting in a “true positive"’ classification. Similarly, when the inferred distance between ToF sensor 510 and a faraway object is above tire distance threshold, the faraway object may not be detected, resulting in a “true negative” classification. The distance threshold can be set or adjusted to meet the detection requirements of the application under consideration.

[0079] FIG. 6 illustrates an implementation of a compartment for receiving and outputting sample containers that may be compared to compartments 330 and 340. As shown, compartment 600 includes ToF sensors 612 and 614, liner 620.. rack 630, and sample containers 642 and 644. ToF sensors 612 and 614 may be compared to ToF sensor 510, and may operate in much the same way. Sample container 642 is positioned in rack 630, whereassample container 644 is positioned directly in liner 620. Therefore, in this particular implementation, the distance between ToF sensor 612 and sample container 642 is 56 mm, whereas the distance between ToF sensor 614 and sample container 644 is 91 mm. Furthermore, in this particular implementation, sample containers 642 and 644 both have a height of 132 mm. As a result, the distance between ToF sensor 612 and the porti on of rack 630 that is directly beneath ToF sensor 612 is 188 mm, and the distance between ToF sensor 614 and the portion of liner 620 that is directly beneath ToF sensor 614 is 223 mm.

[0080] Various modifications can be made to compartment 600. For example, in some implementations, compartment 600, sample container 612, and / or sample container 614 may have different dimensions. For example, any one of these components may be taller or shorter. As another example, in some implementations, ToF sensors 612 and 614 may be repositioned. For example, instead of being positioned on the ceiling of compartment 600, ToF sensors 612 and 614 may be positioned along the sidewalls of compartment 600 and / or beneath liner 620. As yet another example, in some implementations, one or more ToF sensors may be added or removed from compartment 600. As yet another example, in some implementations, as discussed in more detail below, one or more of the ToF sensors in compartment 600 may be modified or replaced with similar object detection sensors.

[0081] In some implementations, a ToF sensor may be positioned on the ceiling of compartment 600 above each receptacle of liner 620. For example, in implementations in which liner 620 has a similar structure to that of liners 401 and 402, compartment 600 may include 30 ToF sensors. In some implementations, rack 630 may be structured such that each one of its receptacles is aligned with a different one of the receptables of liner 620 when rack 630 is positioned in liner 620. As a result, when rack 630 is positioned in liner 620, a ToF sensor is also positioned above each receptacle of rack 630. For example, in some implementations, rack 630 may have a similar structure to that of rack 450. In some implementations, liner 620 and / or rack 630 may be configured to hold more or less sample containers. In such implementations, compartment 600 may consequently include more or less ToF sensors.

[0082] Each one of the ToF sensors of compartment 600 may be configured to detect whether a sample container is positioned in the corresponding receptacle beneath the respective ToF sensor. For example, much like ToF sensor 510, each one of the ToF sensors may be configured to compare a measured distance to a predetermined distance threshold. The distance threshold may be chosen such that, for example, a measured distance of 56 mm (e.g., when thesample container is positioned in rack 630) or 91 mm (e.g, when the sample container is positioned in liner 620) results in a “true positive” classification, and a measured distance of 188 mm (e.g., when there is a rack positioned beneath the sensor) or 223 mm (e.g, when there is no rack positioned beneath the sensor) results in a “true negative” classification. In such implementations, the distance threshold may be anywhere between 91 mm and 188 mm. For example, the distance threshold may be between 120 mm and 150 mm. In implementations in which the dimensions of compartment 600 are changed, the distance threshold may be changed accordingly. Furthermore, in some implementations, one or more of the ToF sensors of compartment 600 may utilize different distance thresholds.

[0083] FIG. 7 is a plot of the measurements obtained from 30 different ToF sensors positioned in the ceiling of compartment 600 of FIG. 6. The measurements were obtained under four different sets of conditions. First, measurements were obtained from each of the ToF sensors when liner 620 was filled with three different racks, each of which was filled with ten sample containers. These measurements are illustrated with ain FIG. 7. Second, measurements were obtained from each of the ToF sensors when liner 620 w as filled with 30 sample containers (e.g., without any racks). These measurements are illustrated with ain FIG. 7. Third, measurements w?ere obtained from each of the ToF sensors when liner 620 was filled with three different racks, each of which was empty. These measurements are illustrated with a “A” in FIG. 7. Fourth, measurements were obtained from each of the ToF sensors when liner 620 was empty (e.g., without any racks or sample containers). These measurements are illustrated with a “x” in FIG. 7.

[0084] During the above-noted tests, BD BACTEC™ culture bottles were used as the sample containers. Furthermore, the caps of these bottles w'ere different colors. More specifically, the bottles numbered 1 through 10 had gray caps, the bottles numbered 11 through 20 had purple caps, the bottles numbered 21 and 22 had silver caps, the bottles numbered 23 and 24 had golden caps, the bottles numbered 25 and 26 had blue caps, and the bottles numbered 27 through 30 had pink caps.

[0085] In FIG. 7, dashed lines are provided at 56 mm, 91 mm, 188 mm, and 223 mm. As discussed above, in some implementations of compartment 600, these are the actual distances between each of the ToF sensors and the corresponding objects beneath these sensors in the above-noted scenarios. For example, when liner 620 is filled with three different racks, each of which was filled with ten sample containers, the actual distance is 56 mm. As another example,when liner 620 is filled with 30 sample containers (e.g, without any racks), the actual distance is 91 mm. As yet another example, when liner 620 is filled with three different empty racks, the actual distance is 188 mm. As yet another example, when liner 620 is completely empty, the actual distance is 223 mm.

[0086] As can be seen in FIG. 7, without any modifications, the ToF sensors are not accurate enough to reliably detect sample containers in compartment 600. For example, when liner 620 is filled with three different racks, each of which was filled with ten sample containers, the measured distances are distributed in a range of approximately 8 mm to approximately 18 mm, which are all far away from their nominal distance line at 56 mm, and dominated by cap-color dependent variations from approximately 70 mm to approximately 1 10 mm. As another example, when liner 620 is filled with 30 sample containers (e.g., without any racks), the measured distances are distributed in a range of approximately 10 nun to approximately 30 mm, which are all far away from their nominal distance line at 91 min, and also dominated by cap-color dependent variations from approximately 100 mm to 160 mm. However, when liner 620 is filled with three different empty racks or when liner 620 is completely empty, the measured distances are distributed in a range of approximately 20 mm to approximately 40 mm, which generally appear between the nominal distance line at 188 mm and the nominal distance line at 223 mm. Nonetheless, due to the inaccuracies of the first two scenarios, there is no distance threshold that can consistently distinguish between the presence or absence of a sample container. It is also worth noting that there are some outliers among the ToF sensors. For example, ToF sensor no. 4 does not generate distance measurements that are distributed in the same way as other ToF sensors, which suggests that it may be defective.

[0087] FIGS. 8A and 8B demonstrate some of the shortcomings and limitations inherently associated with the TOF sensors used in the above-noted tests. For example, FIG. 8A illustrates an optical ToF sensor 810 positioned above a sample container 840. ToF sensor 810 includes emitter 860 and detector 880. ToF sensor 810 may be compared to ToF sensor 510, and may operate in much the same way. Sample container 840 includes cap 842 and shoulder 844. Sample container 840 is also positioned in rack 830, w hich may have a similar structure to that of rack 450. During operation, ToF sensor 810 emits a light pulse 862 (e.g., at approximately 850 nm) towards sample container 840. Reflected light pulses 872, 874, and 876 are then received by detector 880. As shown, light pulse 872 is reflected from cap 842, light pulse 874 is reflected from shoulder 844, and light pulse 876 is reflected from rack 830. ToF sensor 810may then perform functions of thresholding, binning, and / or averaging over a detected series of reflected light pulses to generate a range of measured distances.

[0088] As shown in FIG. 8B, light reflected from complex objects may have multiple light intensity peaks over time. A peak may be detected by comparing the measured light intensity to a predetermined threshold. For example, as shown, a first peak may be detected between 100 ns and 150 ns, and a second peak may be detected between 210 ns and 220 ns. Each peak may correspond to a different part of the complex object. For example, in the situation illustrated in FIG. 8A, the first peak may correspond to light reflected from cap 842 and the second peak may correspond to light reflected from shoulder 844. In some implementations, the measured light intensity may be adjustedwith an analog gain value and / or a scaler value) before being compared to the predetermined threshold.

[0089] Integrated circuits (ICs) are constructed in small packages and can provide cost- effective solutions. For example, ToF sensor 810 may reliably measure short distances to large, uniform objects. However, the accuracy of its distance measurements may start to deteriorate as (I) the distance to the target object increases, (2) the size of the target object decreases, and / or (3) the shape of the target object becomes more complex. The first two of these potential causes of deterioration may be, at least partially, explained by divergent light. Divergent light emitted from emitter 860 may form an illumination conethat is 25° + / - 5°). As the distance between ToF sensor 810 and a target object increases, the field of view (FOV) of this illumination cone also increases. As a result, the target object intercepts a smaller proportion of the FOV, and other objects in the FOV may generate more noise, which reduces the accuracy of ToF sensor 810. Similarly, when a target object is smaller, it may also intercept a smaller proportion of the FOV of the illumination cone.

[0090] In the scenario illustrated in FIG. 6, if (I) the distance between ToF sensor 612 and the cap of sample container 642 is 56 mm, (2) divergent light emitted from ToF sensor 612 forms an illumination cone that is 25°, and (3) the cap of sample container 642 has a diameter of 17 mm, then the cap of sample container 642 may intercept approximately 47% of the FOV of the illumination cone. Furthermore, if (1) the distance between ToF sensor 614 and the cap of sample container 644 is 91 mm, (2) divergent light emitted from ToF sensor 614 forms an illumination cone that is 25°, and (3) the cap of sample container 644 has a diameter of 17 mm, then the cap of sample container 644 may intercept approximately 18% of the FOV of the illumination cone. In either case, a smaller amount of si gnal light is reflected from the cap anda larger amount of noisy light is reflected from the background, resulting in distance measurements of poorer Signal to Noise Ratio (SNR).{0091] To address some of the shortcomings and limitations inherently associated with TOF sensors, such as ToF sensors 510, 612, 614, and 810, a variety of different spatial filters have been designed. These spatial filters may, for example, reduce the angle of the illumination cone produced by these sensors. For example, in some implementations, the spatial filters may reduce the angle of the illumination cone from approximately 25° to approximately 10°. By applying such filters to, for example, ToF sensors 612 and 614 in the above-noted scenarios, the caps of sample containers 642 and 644 may intercept most or even all of the FOV of the illumination cones produced by ToF sensors 612 and 614, respectively. As a result, the amount of noisy light reflected from the background is reduced. Furthermore, by focusing on the caps and ignoring other parts of the sample containers (e.g. , the shoulders), the shape of the target object is effectively simplified to a flat, uniform shape.

[0092] FIG. 9 illustrates a system 900 that includes an optical ToF sensor 910 coupled with a spatial filter 950. ToF sensor 910 includes emitter 960 and detector 980. ToF sensor 910 may be compared to ToF sensor 510, and may operate in much the same way. A proximal end of spatial filter 950 is flush with a housing of ToF sensor 910 and aligned with emitter 960 such that light pulses emitted by emitter 960 are directed through an interior passage of spatial filter 950. As shown, spatial filter 950 is a hollow cylindrical tube that is centered around an aperture of emitter 960. Furthermore, as shown, a diameter of the interior passage of spatial filter 950 is greater than a diameter of the aperture of emitter 960. In some implementations, the diameter of the interior passage may be approximately 1 mm and the diameter of the aperture may be approximately 0.5 mm. In some such implementations, spatial filter 950 may also have a length of approximately 5.7 mm. In some implementations, spatial filter 950 may be constructed from plastic and / or metal materials. In some implementations, spatial filter 950 may have one or more black-colored surfaces. For example, some or all of the surface of the interior passage of spatial filter 950 may be black, which advantageously absorbs light. However, in other implementations, the surface of the interior passage of spatial filter 950 may be one or more different colors.

[0093] Spatial filter 950 advantageously reduces the angle of the illumination cone produced by emitter 960. In some implementations, spatial filter 950 may reduce the angle of the illumination cone produced by emitter 960 from approximately 25° to approximately 10°.For example, as shown, emiter 960 may emit a light pulse 962 with a cone angle of approximately 25°. However, after traveling through spatial filter 950, a light pulse 964 with a cone angle of approximately 10° may exit a distal end of spatial filter 950. Furthermore, as shown, a cap 942 of a sample container may advantageously intercept all of light pulse 964. For example, if (1) the distance between ToF sensor 910 and cap 942 is approximately 56 mm and (2) the cone angle of light pulse 964 is approximately 10°, then light pulse 964 will cover a circular area of approximately 9.8 mm in diameter when at the location of cap 942. Under such circumstances, if cap 942 has a larger diameter of, for example, 17 mm, then it will intercept all of light pulse 964. Similarly, if (1) the distance between ToF sensor 910 and cap 942 is approximately 91 mm and (2) the cone angle of light pulse 964 is approximately 10°, then light pulse 964 will cover a circular area of approximately 16 mm in diameter when at the location of cap 942. Under such circumstances, if cap 942 has a larger diameter of, for example, 17 mm, then it will intercept all of light pulse 964.

[0094] Various modifications can be made to system 900. For example, in some implementations, the shape of spatial filter 950 may be changed. For example, instead of having a circular-shaped cross-section, spatial filter 950 may have an oval-shaped cross-section, a square-shaped cross-section, a hexagonal-shaped cross-section, an octagonal-shaped cross- section, or an irregular-shaped cross-section. In some implementations, spatial filter 950 may have a cross-section shaped in a manner that corresponds to a target object. In some implementations, instead of being hollow, spatial filter 950 may be filled with a transparent material (e g., plastic or glass). In some implementations, one or more optical components, such as one or more collimating lenses and / or one or more focusing lenses, may be added to spatial filter 950. In some implementations, spatial filter 950 may be moved. For example, instead of being aligned with emitter 960, spatial filter 950 may be aligned with detector 980 such that light pulses recei ved by detector 980 first travel through the interior passage of spatial fiter 950. By reducing the FOV of detector 980 in this manner, a smaller amount of noisy light (e.g., light that is reflected from the background rather than the target object) is received by detector 980, resulting in an improved SNR.

[0095] FIG. 10 illustrates a system 1000 that includes an optical ToF sensor 1010 coupled with a spatial filter 1050. ToF sensor 1010 includes an emitter (not shown) and a detector (not shown). ToF sensor 1010 may be compared to ToF sensor 510, and may operate in much the same way. A proximal end of spatial filter 1050 is flush with a housing of ToF sensor 1010 andpositioned over both the emitter and the detector of ToF sensor 1010. As shown, spatial filter 1050 is a Micro Honeycomb Spatial Filter (MHSF) that includes tubes 1052 and 1054. Tube 1052 is aligned with the emitter of ToF sensor 1010 such that light pulses emitted by the emitter are directed through an interior passage of tube 1052. Tube 1054 is aligned with the detector of ToF sensor 1010 such that light pulses received by the detector first travel through an interior passage of tube 1054.

[0096] Tubes 1052 and / or 1054 may be hollow cylindrical tubes that are centered around apertures of the emitter and the detector of ToF sensor 1010, respectively. In some implementations, a diameter of the interior passages of tubes 1052 and / or 1054 may be greater than a diameter of the apertures of the emitter and the detector of ToF sensor 1010, respectively. For example, the diameters of the interior passages may be approximately 0.83 mm and the diameters of the apertures of the emitter and the detector may be 0.5 mm and 0.3 mm, respectively. In some such implementations, spatial filter 1050 may also have a length of approximately 4.7 mm. In some implementations, spatial filter 1050 may be constructed from plastic and / or metal materials. In some implementations, spatial filter 1050 may have one or more black-colored surfaces. For example, some or all of the surfaces of the interior passages of tubes 1052 and / or 1054 may be black, which advantageously absorbs light. However, in other implementations, the surfaces of the interior passages of tubes 1052 and / or 1054 may be one or more different colors.

[0097] Spatial filter 1050 advantageously reduces both the angle of the illumination cone produced by the emitter of ToF sensor 1010 and the FOV of the detector of ToF sensor 1010. In some implementations, spatial filter 1050 may reduce the angle of the illumination cone produced by the emitter from approximately 25° to approximately 10°. For example, the emitter may emit a light pulse with a cone angle of approximately 25°. However, after traveling through tube 1052, a light pulse 1064 with a cone angle of approximately 10° may exit a distal end of tube 1052. As a result, a cap of a sample container (not. shown) may advantageously intercept all of light pulse 1064. For example, if (1) the distance between ToF sensor 1010 and the cap is approximately 56 nun and (2) the cone angle of light pulse 1064 is approximately 10°, then light pulse 1064 will cover a circular area o f approx imately 9.8 mm in diameter when at the location of the cap. Under such circumstances, if the cap of the sample container has a larger diameter of, for example, 17 mm, then it will intercept all of light pulse 1064. Similarly, if (1) the distance between ToF sensor 1010 and the cap is approximately 91 mm and (2) thecone angle of light pulse 1064 is approximately 10°, then light pulse 1064 will cover a circular area of approximatelymm in diameter when at the location of the cap. Under such circumstances, if the cap of the sample container has a larger diameter of, for example, 17 nun, then it will intercept all of light pulse 1064.

[0098] Various modifications can be made to system 1000. For example, in some implementations, the shape of spatial filter 1050 may be changed. For example, instead of having a circular-shaped cross-section, the tubes of spatial filter 1050 may have an oval-shaped cross-section, a square-shaped cross-section, a hexagonal-shaped cross-section, an octagonalshaped cross-section, or an irregular-shaped cross-section. In some implementations, one or more of the tubes of spatial filter 1050 may have a cross-section shaped in a manner that corresponds to a target object. In some implementations, instead of being hollow, the tubes of spatial filter 1050 may be filled with a transparent material (e.g., plastic or glass). In some implementations, rather than having approximately the same length, the tubes of spatial filter 1050 may have different lengths. For example, tube 1052 may be shorter than tube 1054 and visa versa. In some implementations, one or more optical components, such as one or more collimating lenses and / or one or more focusing lenses, may be added to spatial filter 1050.

[0099] FIG. 11 illustrates a system 1100 that includes an optical ToF sensor 1 110 coupled with a spatial filter 1 150. ToF sensor 1110 includes an emitter 1 160 and a detector 1180. ToF sensor 1110 may be compared to ToF sensor 510, and may operate in much the same way. As shown, ToF sensor 1110 is positioned within a recess of spatial filter 1150. In some implementations, the recess of spatial filter 1150 may be sized such that the sidewalls and the bottom surface of the housing of ToF sensor 1110 are covered and only the top surface of the housing of ToF sensor 1 110 is exposed. As shown, spatial filter 1150 is a Micro Spatial Filter (MSF) that includes tubes 1152 and 1154. Tube 1152 is aligned with emitter 1160 such that light pulses emitted by emitter 1160 are directed through an interior passage of tube 1152. Tube 1 154 is aligned with detector 1 180 such that light, pulses received by detector 1 180 first travel through an interior passage of tube 1154.

[0100] Tubes 1152 and / or 1154 may be hollow cylindrical tubes that are centered around apertures of emitter 1160 and detector 1180, respectively. In some implementations, a diameter of the interior passages of tubes 1152 and / or 1154 may be greater than a diameter of the apertures of emitter 1 160 and detector 1 180, respectively. For example, the diameters of the interior passages may be approximately 1 nun and the diameters of the apertures ofemitter 1160 and detector 1180 may be 0.5 mm and 0.3 mm, respectively. In some such implementations, spatial filter 1150 may also have a length of approximately 5.7 mm. In some implementations, spatial filter 1 150 may be constracted from plastic and / or metal materials. In some implementations, spatial filter 1 150 may have one or more black-colored surfaces. For example, some or all of the surfaces of the interior passages of tubes 1152 and / or 1 154 may be black, which advantageously absorbs light. However, in other implementations, the surfaces of the interior passages of tubes 1152 and / or 1 154 may be one or more different colors.

[0101] Spatial filter 1 150 advantageously reduces both the angle of the illumination cone produced by emitter 1160 and the FOV of detector 1180. In some implementations, spatial filter 1150 may reduce the angle of the illumination cone produced by emitter 1 160 from approximately 25° to approximately 10°. For example, emitter 1160 may emit a light pulse with a cone angle of approximately 25°. However, after traveling through tube 1 152, a light pulse 1 164 with a cone angle of approximately 10° may exit a distal end of tube 1152. As a result, a cap of a sample container (not shown) may advantageously intercept all of light pulse 1164. For example, if (1) the distance between ToF sensor 1110 and the cap is approximately 56 mm and (2) the cone angle of light pulse 1 164 is approximately 10°, then light pulse 1 164 will cover a circular area of approximately 9.8 nun in diameter when at the location of the cap. Under such circumstances, if the cap of the sample container has a larger diameter of, for example, 17 mm, then it will intercept all of light pulse 1164. Similarly, if (1) the distance between ToF sensor 11 10 and the cap is approximately 91 mm and (2) the cone angle of light pulse 1164 is approximately 10°, then light pulse 1164 will cover a circular area of approximately 16 mm in diameter when at the location of the cap. Under such circumstances, if the cap of the sample container has a larger diameter of, for example, 17 mm, then it will intercept all of light pulse 1164.

[0102] Various modifications can be made to system 1100. For example, in some implementations, the shape of spatial filter 1 150 may be changed. For example, instead of having a circular-shaped cross-section, tubes 1152 and / or 1154 may have an oval-shaped crosssection, a square-shaped cross-section, a hexagonal-shaped cross-section, an octagonal-shaped cross-section, or an irregular-shaped cross-section. In some implementations, tubes 1 152 and / or 1154 may have a cross-section shaped in a manner that corresponds to a target object. In some implementations, instead of being hollow, tubes 1 152 and / or 1154 may be filled with a transparent material (e.g., plastic or glass). In some implementations, rather than havingapproximately the same length, tubes 1152 and 1154 may have different lengths. For example, tube 1152 may be shorter than tube 1154 and visa versa. In some implementations, one or more optical components, such as one or more collimating lenses and / or one or more focusing lenses, may be added to spatial filter 1 150 (e.g., within tubes 1 152 and 1 154).

[0103] As can be seen above, spatial filters 1050 and 1 150 provide many of the same advantages despite having different structures. However, there are some distinctions between these two filters. For example, spatial filter 1050 may cost less than spatial filter 1150. Aluminum honeycombs, for example, are widely available and used in a variety of different applications. However, it can be difficult to align two of the tubes of spatial filter 1050 with the emitter and the detector of an optical ToF sensor. Spatial filter 1150 may cost more than spatial filter 1050, but it includes a recess that can be used to easily align the emitter and the detector of an optical ToF sensor with tubes 1 152 and 1154. In implementations where the recess is sized for a specific ToF sensor, simply inserting the ToF sensor into the recess will align the emitter and the detector of that sensor with tubes 1152 and 1154.

[0104] FIGS. 12A-12D illustrate a system 1200 that includes an optical ToF sensor 1210 coupled with a spatial filter 1250. More specifically, FIG. 12A illustrates an exploded view of ToF sensor 1210 and spatial filter 1250, FIG. 12B illustrates a cross-section of ToF sensor 1210 coupled with spatial filter 1250, FIG. 12C illustrates a perspective view of spatial filter 1250, and FIG. 12D illustrates a cross-section of spatial filter 1250. ToF sensor 1210 includes an emitter 1260 and a detector 1280. ToF sensor 1210 may be compared to ToF sensor 510, and may operate in much the same way. As shown, ToF sensor 1210 is positioned within a recess 1258 of spatial filter 1250. In some implementations, recess 1258 may be sized such that the sidewalls and the bottom surface of the housing of ToF sensor 1210 are covered and only the top surface of the housing of ToF sensor 1210 is exposed. As shown, spatial filter 1250 is an MSF that includes passages 1252 and 1254. Passage 1252 is aligned with emitter 1260 such that light pulses emitted by emitter 1260 are directed through passage 1252. Passage 1254 is aligned with detector 1280 such that light pulses received by detector 1280 first travel through passage 1254.

[0105] Passages 1252 and / or 1254 may have circular-shaped cross-sections and may be centered around apertures of emitter 1260 and detector 1280, respectively. In some implementations, a diameter of passages 1252 and / or 1254 may be greater than a diameter of the apertures of emitter 1260 and detector 1280, respectively. For example, the diameters ofpassages 1252 and / or 1254 may be approximately 1 mm and the diameters of the apertures of emitter 1260 and detector 1280 may be 0.5 mm and 0.3 mm, respectively. In some such implementations, spatial filter 1250 may also have a length of approximately 5.7 mm. In some implementations, spatial filter 1250 may be constructed from plastic and / or metal materials. In some implementations, spatial filter 1250 may have one or more black-colored surfaces. For example, some or all of the surfaces of passages 1252 and / or 1254 may be black, which advantageously absorbs light. However, in other implementations, the surfaces of passages 1252 and / or 1254 may be one or more different colors.

[0106] Spatial filter 1250 advantageously reduces both the angle of the illumination cone produced by emitter 1260 and the FOV of detector 1280. In some implementations, spatial filter 1250 may reduce the angle of the illumination cone produced by emitter 1260 from approximately 25° to approximately 10°. For example, as shown, emitter 1260 may emit a light pulse 1262 with a cone angle of approximately 25°. However, after traveling through passage 1252, a light pulse 1264 with a cone angle of approximately 10° may exit a distal end of passage 1252. As a result, a cap of a sample container (not shown) may advantageously intercept all of light pulse 1264. For example, if (1) the distance between ToF sensor 1210 and the cap is approximately 56 mm and (2) the cone angle of light pulse 1264 is approximately 10°, then light pulse 1264 will cover a circular area of approximately 9.8 mm in diameter when at the location of the cap. Under such circumstances, if the cap of the sample container has a larger diameter of, for example, 17 nun, then it will intercept all of light pulse 1264. Similarly, if (1 ) the distance between ToF sensor 1210 and the cap is approximately 91 min and (2) the cone angle of light pulse 1264 is approximately 10°, then light pulse 1264 will cover a circular area of approximately 16 mm in diameter when at the location of the cap. Under such circumstances, if the cap of the sample container has a larger diameter of, for example, 17 nun, then it will intercept all of light pulse 1264.

[0107] Various modifications can be made to system 1200. For example, in some implementations, the shape of spatial filter 1250 may be changed. For example, instead of having a circular-shaped cross-section, passages 1252 and / or 1254 may have an oval-shaped cross-section, a square-shaped cross-section, a hexagonal-shaped cross-section, an octagonalshaped cross-section, or an irregular-shaped cross-section. In some implementations, passages 1252 and / or 1254 may have a cross-section shaped in a manner that corresponds to a target object. In some implementations, instead of being hollow, passages 1252 and / or 1254may be filled with a transparent material (c.g., plastic or glass). In some implementations, rather than having approximately the same length, passages 1252 and 1254 may have different lengths. For example, passage 1252 may be shorter than passage 1254 and visa versa. In some implementations, one or more optical components, such as one or more collimating lenses and / or one or more focusing lenses, may be added to spatial filter 1250 (<?.g., within passages 1252 and 1254).

[0108] As can be seen above, spatial filters 1 150 and 1250 have very similar structures. However, spatial filter 1250 has also been advantageously designed such that it can be even more efficiently manufactured using, for example, 3D printing technology. Notably, spatial filter 1250 has less support structures than spatial filter 1 150. For example, spatial filter 1150 includes support structures 1156 to support tubes 1152 and 1 154, whereas spatial filter 1250 does not include comparable support structures. As a result, spatial filter 1250 can, for example, be printed flat on a 3D printing platform without any support material, which can increase component accuracy and printability while reducing time and effort related to post-processing. Spatial filter 1250’s simplistic design also ensures quicker washing and less waste. Moreover, since the walls of passages 1252 and 1254 may be thicker than the wall of tubes 1152 and 1154, spatial filter 1250 may more effectively block light.

[0109] It was also discovered that the manufacture of MSFs, such as spatial filter 1250, could be further optimized by using (1 ) Micro Digital Light Processing (DLP), (2) Vero Ultra Black photopolymer ink, and / or (3) a thin-release film printing substrate. As noted above, in some implementations, the diameters of passages 1252 and 1254 may be approximately I mm and the length of spatial filter 1250 may be approximately 5.7 mm. Such dimensions push the envelope on readily available 3D printing capabilities. For example, in some implementations, a 3D printing resolution of less than 25pm may be required. A Micro DLP 3D printer can meet such specifications. Micro DLP is a 3D printing technology that makes use of an extremely high-resolution DLP projector to selectively cure photopolymer materials in a phase change process from liquid to solid form on a layered basis. In some implementations, a Micro DLP 3D printer may be able to print 30 or more MSFs every 30 minutes.

[0110] Identifying a suitable printing material was a significant challenge. First the material must be capable of resolving fine features (e.g., less than 25pm) and printing accurate!}' across all features and directions (e.g., X, Y, and Z directions). The next consideration was cleanability. Due to the nature of the Micro DLP 3D printing process, whenthe print is completed, the 3D printed components are covered in uncured liquid photopolymer. This uncured liquid photopolymer must clean away easily and rapidly from all surfaces and passages of the component. Finally, the material should be opaque and block light, even with rvall thicknesses of less than 25pm. Several photopolymer materials were tested. While the thicker cross-sections of many of the tested materials appeared opaque, the thinner cross- sections often appeared more translucent. However, through this testing, Vero Ultra Black photopolymer ink was identified as a suitable printing material. Vero Ultra Black photopolymer ink was developed for PolyJet 3D printing, and is not believed to have ever been used in a Micro DLP 3D printing process. As a result, it was initially challenging to work with, but ultimately proved to print accurately and wash efficiently while still providing suitable opacity at thin cross-sections.[Oil 1] A release film is an adhesive-based laminate. It can be stuck onto a build platform’s surface and used as a printing substrate. A thin-release film printing substrate allows MSFs to be secure for printing and post-processing, while also enabling easy platform removal, resulting in damage-free MSFs. Batches of MSFs printed on a thin-release film printing substrate can also be easily traced since they can be printed and washed together on the same substrate.

[0112] FIG. 13 may be compared to FIG. 7. FIG. 13 is a plot of the measurements obtained from the same 30 ToF sensors. The measurements were obtained under the same four different sets of conditions, and with the same sample containers. However, during this test, all of the ToF sensors were coupled with MSFs that may be compared to spatial filter 1250. Each MSF was 5.7 mm long and had passages with 1 mm diameters.

[0113] A comparison between FIGS. 7 and 13 reveals that the MSFs significantly improve the accuracy of the ToF sensors. As a result, the modified ToF sensors can be used to reliably detect sample containers in compartment 600. For example, when liner 620 is filled with three different racks, each of which was filled with ten sample containers, the measured distances are distributed in a range of approximately 8 mm to approximately 14 ram, which are all distributed around their nominal distance line at 56 mm, and cap-color independent. As another example, when liner 620 is filled with 30 sample containers (e.g., without any racks), the measured distances are distributed in a range of approximately 10 mm to approximately 18 mm, which are all distributed around their nominal distance line at 91 mm, and cap-color independent. As yet another example, when liner 620 is filled with three different empty racks or when liner 620 is completely empty, the measured distances are distributed in a range ofapproximately 16 mm to approximately 28 mm, which generally appear between the nominal distance line at 188 mm and the nominal distance line at 223 mm. As shown in FIG. 13, there is a clear zone for distance separation between the two scenarios of presence and absence. Any distance threshold between, for example, approximately 1 15 mm and approximately 170 mm may be used to detennine whether a sample container is present or absent. For example, measured distances that are less than or equal to 170 mm may reliably indicate that a sample container is present. As another example, measured distances that are greater than or equal to 115 mm may reliably indicate that a sample container is absent.

[0114] It is also worth noting that ToF sensor no. 4 is not an outlier in FIG. 13. This suggests that the MSFs may also help to alleviate defects in the ToF sensors. For example, an MSF may help convert a tilted illumination cone of wide-angle (e.g, caused by a partial blockage of dust on the emitting aperture or a tilted VCSEL inside the ToF sensor package) back into a normal cone of the narrow-angle.

[0115] FIGS. 14A and 14B illustrate an implementation of a compartment for receiving and outputting sample containers that may be compared to compartment 600. As shown in FIG. 14A, compartment 1400 includes liner 1420 and sample containers 1440. As shown in FIG. I4B, compartment 1400 further includes racks 1430. Racks 1430 are positioned in liner 1420. Each one of racks 1430 is filled with ten of sample containers 1440. In FIGS. 14A and 14B several of sample containers 1440 are tilted .

[0116] FIG. 14C may be compared to FIG. 13. FIG. 14C is a plot of the measurements obtained from the same 30 ToF sensors. The measurements were obtained under two of the same sets of conditions, and with the same sample containers. Furthermore, each ToF sensor was coupled with the same MSF. However, during this test, some of the sample containers were tilted in the maimer shown in FIGS. 14A and 14B.

[0117] As shown in FIG. 14C, even when the sample containers are tilted, the modified ToF sensors can still be used to reliably detect sample containers in compartment. 600. For example, when liner 620 is filled with three different racks, each of which was tilled with ten sample containers, the measured distances are all less than approximately 130 mm. As another example, when liner 620 is filled with 30 sample containers (e.g., without any racks), the measured distances are all less than approximately 165 nun. As a result, there is still a clear zone for distance separation between the two scenarios of presence and absence. A distancethreshold of, for example, approximately 170 mm may still be used to reliably determine whether a sample container is present or absent.

[0118] As utilized herein, the terms “approximately,” “about,” “substantially” and similar terms are intended to have a broad meaning in harmony with the common and accepted usage by those of ordinary skill in the art to which the subject matter of this disclosure pertains. It should be understood by those of skill in the art who review this disclosure that these terms are intended to allow a description of certain features described without restricting the scope of these features to the precise numerical ranges provided. Accordingly, these terms should be interpreted as indicating that insubstanti al or inconsequential modifications or alterations of the subject matter described and are considered to be within the scope of the disclosure.

[0119] From the foregoing and with reference to the various figure drawings, those skilled in the art will appreciate that certain modifications may also be made to the present disclosure without departing from the scope of the same. For example, in some implementations, a spatial filter may be implemented with other types of optical components. For example, a small lens (e.g., a micro lens) may be used to reduce the angle of the illumination cone produced by an emitter of a ToF sensor and the FOV of a detector of the ToF sensor. However, such a lens would need to ( 1) be properly designed or selected with the right focal length and diameter and (2) be properly positioned in front of the aperture of the emitter or the detector. In some implementations, the front and back surfaces of the lens may have anti-reflection coatings to minimize reflections for potential cross-talks. In some implementations, a lens housing may be used to install the lens at the desired location relative to the TOF sensor. However, in comparison to some of the spatial filters described above, the cost of the lens alone may be more than expensive.

[0120] As another example, in some implementations, a spatial filter may be implemented with a thin plate having two small holes, which are aligned with the emitter and the detector of a ToF sensor, respectively. In such implementations, both the distance between the plate and the ToF sensor and the diameter of the holes govern how the angle of the illumination cone produced by the emitter is reduced and / or how the angle of the FOV of the detector is reduced. In some implementations, the plate may be constructed from a material with dark surfaces for absorbing light. In some implementations, a small piece of isolating plate may be used to block unwanted reflections to stop potential crosstalk. In some implementations, a housing may beused to couple and / or align the plate with the ToF sensor. For example, the spatial filter may be implemented as a hollow box with two small holes.

[0121] While several implementations of the disclosure have been shown in the drawings, it is not intended that the disclosure be limited thereto, as it is intended that the disclosure be as broad in scope as the art will allow and that the specification be read likewise. Therefore, the above description should not be construed as limiting, but merely as exemplifications of particular implementations. Those skilled in the art will envision other modifications within the scope and spirit of the claims appended hereto.

Claims

CLAIMS1. A system comprising: an optical time-of-flight sensor comprising an emiter for transmitting an optical signal towards an object; and a detector for receiving an optical signal reflected off the object; and a spatial filter comprising a first passage, wherein the first passage is aligned with (a) the emitter such that the transmitted optical signal passes through the first passage before contacting the object or (b) the detector such that the received optical signal passes through the first passage before contacting the detector, and wherein the spatial filter reduces an angle of (a) an illumination cone produced by the emitter or (b) a field of view of the detector.

2. The system of claim 1. wherein the first passage is aligned with the emitter such that the transmitted optical signal passes through the first passage before contacting the object, and wherein the spatial filter reduces the angle of the illumination cone produced by the emitter.

3. The system of claim 2, wherein the spatial filter further comprises a second passage, wherein the second passage is aligned with the detector such that the received optical signal passes through the second passage before contacting the detector, and wherein the spatial filter reduces the angle of the field of view of the detector.

4. The system of claim 3, wherein the spatial filter further comprises a tube with an interior passage comprising tire first or second passage.

5. The system of any one of claims 2 to 4, wherein the spatial filter reduces the angle of the illumination cone from approximately 25° to approximately 10°.

6. The system of claim 1 , wherein the first passage is aligned with the detector such that the received optical signal passes through the first passage before contacting the detector, and wherein the spatial filter reduces the angle of the field of view of the detector.

7. The system of any one of claims 1 to 6, wherein the spatial filter further comprises a recess configured to (a) receive the optical time-of-flight sensor and (b) align the first passage with at least one of the emitter or the detector.

8. The system of any one of claims 1 to 7, wherein the spatial filter is a micro honeycomb spatial filter.

9. The system of any one of claims 1 to 7, wherein the spatial filter is a micro spatial filter.

10. The system of claim 9, wherein the micro spatial filter is printed using micro digital light processing.

11. The system of claim 9 or 10, wherein the micro spatial filter is printed with Vero Ultra Black photopolymer ink.

12. The system of any one of claims 9 to 1 1, wherein the micro spatial filter is printed on a thin-release film printing substrate.

13. The system of any one of claims 1 to 12, further comprising: a compartment configured to (a) receive individual untested sample containers or a rack of untested sample containers or (b) output individual positive sample containers or a rack of positive sample containers, wherein the optical time-of-flight sensor is coupled to a ceiling of the compartment and configured to detect the presence or absence of a sample container.

14. The system of claim 13, wherein the compartment comprises a liner with one or more sections, wherein each of the one or more sections comprises: a plurality of receptacles configured to accept sample containers directly; and a pair of recesses configured to accept a rack of sample containers.

15. The system of claim 13 or 14, wherein the sample containers are blood culture botles.

16. A spatial filter comprising: a first passage, wherein the spatial filter is configured to couple with an optical time-of-flight sensor comprising (a) an emitter for transmitting an optical signal towards an object and (b) a detector for receiving an optical signal reflected off the object, wherein the first passage is configured to align with (a) the emiter such that the transmitted optical signal passes through the first passage before contacting the object or (b) the detector such that the received optical signal passes through the first passage before contacting tire detector, and wherein the spatial filter is configured to reduce an angle of (a) an illumination cone produced by the emitter or (b) a field of view of the detector.

17. The spatial filter of claim 16, wherein the first passage is configured to align with the emitter such that the transmited optical signal passes through the first passage before contacting the object, and wherein the spatial filter is configured to reduce the angle of the illumination cone produced by the emitter.

18. The spatial filter of claim 17, wherein the spatial filter further comprises a second passage, wherein the second passage is configured to align with the detector such that the received optical signal passes through the second passage before contacting the detector, and wherein the spatial filter is configured to reduce the angle of the field of view' of the detector.

19. The spatial filter of claim 16, wherein the first passage is configured to align with the detector such that the received optical signal passes through the first passage before contacting the detector, and wherein the spatial filter is configured to reduce the angle of the field of view of the detector.

20. The spatial filter of any one of claims 16 to 19, further comprising a recess configured to (a) receive the optical time-of-flight sensor and (b) align the first passage with at least one of the emitter or the detector.

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