Abstract:
A patient identification system based on a portable data terminal including a biometric data capture device for capturing biometric scan data from a person and creating a biometric template for the person. A reference biometric template is prepared based oil a biometric scan of patient. Software is provided on the portable data terminal to compare the biometric template captured by the portable data terminal to the reference biometric template and indicate a whether the person corresponds to the patient described by the reference biometric template.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    Certain organizations, such as hospitals, have a significant interest in ensuring that services are provided to the correct individual. Wristbands are commonly used within a hospital to ensure that patients are correctly identified for medical treatment. Some hospitals print a barcode, unique to the patient, onto the wristband, which may be scanned at the time medication is provided to the patient, either to automatically dispense the proper medication from a cart or to ensure the proper medication container is selected by scanning a similar barcode on that container. The barcodes may be scanned by a portable hand held scanner or with a portable data terminal. 
         [0002]    The term portable data terminal (PDT) refers to data collection devices used to collect, process, and transfer data to a larger data processing system. Most PDTs are ruggedized to some extent for use in industrial environments. PDT&#39;s are available from several sources, including the assignee of the present application: HAND HELD PRODUCTS, INC. 
         [0003]    A PDT generally comprises a mobile computer, a keypad, and a data acquisition device. The mobile computer generally comprises a hand held (or “pocket”) computing device, such as those available from INTEL, PALM, HEWLETT PACKARD, and DELL. Keypads come in a variety of alpha-numeric and numeric configurations. The data acquisition device generally comprises a device that captures data from, for example, radio frequency IDs (RFID), images, and bar codes. Data may also be captured via keypad entry and utilization of a touch pad associated with the mobile computer. 
         [0004]      FIG. 1A  is an orthogonal view of a known PDT  100 .  FIG. 1B  is a plan view of the known PDT  100 . The illustrated example utilizes a popular form factor incorporating a body  102  and a handle  101 . The body  102  generally supports a variety of components, including: a battery (not shown but typically located the rear half of the body): an LCD with touch screen  106 : a keyboard  108  (including a scan button  108   a ); a scan engine  110 ; and a data/charging port  112  (not fully illustrated). The scan engine  110  may comprise, for example, an image engine or a laser engine. The data/charging port  1112  typically comprises a proprietary interface with one set of pins or pads for the transmitting and receiving of data and a second set of pins or pads for receiving power for powering the system and/or charging the battery. 
         [0005]    The handle  101 , extending from a bottom surface of the body  102 , incorporates a trigger  114 . In use, the user may actuate either the scan key  108   a  or the trigger  114  to initiate a frame capture via the image engine  110 . The captured frame may either be processed as an image or as a data carrier. In the first case, the captured frame may undergo some post capture image processing, such as de-speckling or sharpening and then stored as an image file (e.g. a bitmap, jpeg of gif file) and possibly displayed. In the second case the captured frame also undergoes some post capture image processing but the image is then analyzed, e.g. decoded, to identify data represented therein. The decoded data is stored and possibly displayed on the PDT  100 . Additional processing of the image or data may take place on the PDT  100  and/or a data processing resource to which the data is transmitted via any available transport mechanism on the PDT  100 . Some examples of known transport mechanisms utilized by PDT&#39;s include: Bluetooth, WiFi, GSM, CDMA, USB, IrDA, removable FLASH memory, parallel and serial ports (including for example, RS-232). 
         [0006]    While the use of barcodes on patient Wristbands may reduce, it has not eliminated incorrect identification of patients. Further, the reliability of such barcodes may be conditioned upon the position of the patient at the time of scanning. It is also to be noted that PDT provide a significant amount of processing power that could be used to reduce incorrect identification of patients. Accordingly, the present Inventors have recognized a need for improved identification apparatus and methods for identifying patients. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]    An understanding of the present invention can be gained from the following detailed description of embodiments of the invention taken in conjunction with the accompanying drawings of which: 
           [0008]      FIG. 1A  is an orthogonal view of a known PDT. 
           [0009]      FIG. 1B  is a plan view of a known PDT. 
           [0010]      FIG. 2  is a block diagram of a PDT in accordance with an embodiment of the present invention. 
           [0011]      FIG. 3  is a flow chart of a method that may be utilized by the described embodiments of the present invention. 
           [0012]      FIG. 4  is a conceptual screen shot of a user interface that may be utilized in the described embodiments of the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0013]    Reference will now be made in detail to the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout. The following description will use nomenclature associated with an imager based PDT, however those of ordinary skill in the art will recognize that the present invention is applicable to a variety of portable devices including RF or magstripe based PDTs, personal data assistants (PDAs): bar code scanners, and consumer electronics, for example digital cameras, cellular phones, and the like. It is anticipated that many such portable devices would benefit from the present invention, including the embodiments thereof described herein. 
         [0014]    A method is here, and generally, conceived to be a sequence of steps or actions leading to a desired result and may be implemented as software. While it may prove convenient to discuss such software as if were embodied by a single program, most implementations will distribute the described functions among discrete (and some not so discrete) pieces of software. These pieces are often described using such terms of art as “programs,” “objects,” “functions,” “subroutines,” “libraries,” “.dlls,” “APIs.” and “procedures.” While one or more of these terms may find favor in the present description there is no intention to limit the invention or the described embodiments to the recited configurations. 
         [0015]    With respect to the software described herein, those of ordinary skill in the art will recognize that there exist a variety of platforms and languages for creating software for performing the methods outlined herein. Embodiments of the present invention can be implemented using MICROSOFT VISUAL STUDIO or any number of varieties of C. However, those of ordinary skill in the art also recognize that the choice of the exact platform and language is often dictated by the specifics of the actual system constructed, such that what may work for one type of system may not be efficient on another system. It should also be understood that the methods described herein are not limited to being executed as software on a processor or DSP (Digital Signal Processor), but can also be implemented in a hardware processor. For example, the methods could be implemented with HDL (Hardware Design Language) in an ASIC. 
         [0016]    In the present description, an element number followed by a letter generally indicates multiple occurrences of similar, either in structure or function, elements. Further, the use of an italicized “n” (e.g. n) associated with an element number generally denotes either an unspecified one of such elements or a partial or complete group of such elements—the meaning of which is to be drawn from the context of such use. 
         [0017]      FIG. 2  is a block diagram of a PDT  1000  in accordance with an embodiment of the present invention. Those of ordinary skill in the art will recognize that the illustrated design of the PDT  1000  has been simplified so as to permit a briefer explanation of systems and components not directly related to the present invention. 
         [0018]    A central processing unit (CPU)  1010  receives data from and outputs data to other sub-systems for storage, transmission and additional processing. CPU  1010  may be implemented using any number of off the shelf solutions including: embedded processors, such as an XSCALE processor available from INTEL; general purpose processors, such as a PENTIUM 4 available from INTEL; or any number of custom solutions including pre-configured field programmable gate arrays (FPGAs) and application specific integrated circuits (ASICs). Overall operation of the CPU  1010  is controlled by software or firmware, typically referred to as an operating system, stored in one or more memory locations  1017   n , including RAM  1017   a  and FLASH memory  1017   b . Examples of suitable operating systems for PDT  1000  include: WINDOWS MOBIL, WINDOWS CE, WINDOWS XP, LINUX, PALM, SYMBIAN, and OSX. 
         [0019]    In general, communication to and from the CPU  1010  and the various sub-components takes place via one or more ports or busses, including a main system bus  1012 : I 2 C busses  1013   a  and  1013   b : a plurality of Universal Asynchronous Receivers/Transmitter (UART) ports  1014   n , a Universal Serial Bus (USB)  1015   n , and an RS-232 port  1016 . 
         [0020]    The illustrated CPU  1010  also includes a liquid crystal display (LCD) controller  1018  for controlling an LCD  1020 . A touch sensitive panel  1021 , which may be in communication with one or more of the CPU  1010  and an auxiliary processor  1024  via the I 2 C bus  1013   b , may be associated with the LCD  1020  for receipt of data thereon. The combination of the LCD  1020  and the touch sensitive panel  1021  is often referred to as a “touch screen.” 
         [0021]    A variety of secondary (or “sub”) processors may be provided to perform general and application specific functions. The example illustrated in  FIG. 2  provides two such processors: a field programmable gate array (FPGA)  1022  and the auxiliary processor  1024 . The FPGA  1022  may comprise any number of FPGA including the Virtex-4 family available from XILINX. The auxiliary processor  1024  may comprise any number of embedded (or general purpose) processors, including the PICmicro® family of microcontrollers available from MICROCHIP TECHNOLOGY. 
         [0022]    The auxiliary processor  1024  may interface with and control a variety of data input devices including, for example, the touch panel  1021 , a keyboard  1034  and a scan button  1036 . By way of example the PDT  1000  may be configured so that displayed menu options are selected by physically depressing a key on the keyboard  1034  or activating the touch screen  1021  with use of a finger or stylus. The scan button  1036  may be used for initiating and controlling the various data collection systems, such as an image signal generating system  1028 , an RFID sensing system  1030 , or a magnetic stripe reader  1040 . 
         [0023]    The data collection systems (e.g. the image signal generating system  1028 , the RFID sensing system  1030 , and the magnetic stripe reader  1050 ) may be controlled by one or more of the CPU  1010 , the auxiliary processor  1024 , and the FPGA  1022 . In this case, the FPGA  1022  initiates and controls the operation of the data collection systems and accumulates data received there from prior to depositing such data in memory  1017   n . Possible configurations of FPGA  1022  are illustrated in U.S. Pat. No. 6,947,612 incorporated herein by reference. 
         [0024]    The image signal generating system  1028  generally comprises a two dimensional solid state image sensor  1029  utilizing such technologies as CCD, CMOS, and CID, for capturing an image containing data, e.g. a bar code or signature. Two-dimensional solid state image sensors generally have a plurality of photo sensor picture elements (“pixels”) which are formed in a pattern including a plurality of rows and a plurality of columns of pixels. The image signal generating system  1028  further includes an imaging optics (not shown) focusing an image onto an active surface of the image sensor  1029 . Image sensor  1029  may be incorporated on an image sensor IC chip having disposed thereon image sensor control circuitry, image signal conditioning circuitry, and an analog-to-digital converter. FPGA  1022  manages the capture and transfer of image data into RAM  1017   n . Decoding may be performed by the CPU  1010  or any suitable secondary processor. Examples of devices suitable for use as the imaging assembly  1028  include an IMAGETEAM 5x00VGA/5x00MPX imaging module of the type available from Hand Held Products, assignee of the present application. A variety of alternatives, including dedicated laser barcode scanners may also be utilized. 
         [0025]    One use of the image signal generating system  1028  is for reading and interpreting bar codes such as bar code  1051  a on an item  1050 . For this operation, when the scan button  1036  is actuated, the CPU  1010  causes the appropriate control signals to be sent to the image sensor  1029 . In response thereto, the image sensor  1029  outputs digital image data including (hopefully) an adequate representation of the bar code symbol  1050 . The digital image data is streamed to the FPGA  1022  where it is collected and subsequently deposited in memory  1017   n . In accordance with a decoding program (not specifically illustrated) an attempt may be made to decode the bar code represented in the captured electronic image representation. The capture and decoding of image data may occur automatically in response to a trigger signal being generated, usually by activation of the scan button  1036  or a pre-selected key on keyboard  1034 . For example, the CPU  1010  may be configured, typically through execution of a program resident in memory  1017   n , to continuously capture and decode bar code symbols represented therein as long as scan button  1036  is actuated. The cycle may be terminated upon successfully decoding the bar code symbol or by timing out after a number of unsuccessful attempts. 
         [0026]    In addition to having a decode operation, the image signal generation system  1028  may also be configured for an image capture operation. In an image capture operation, control circuit  1010  captures an electronic image representation in response to the scan button  1036  being actuated without attempting to decode a decodable symbol represented therein. The captured electronic image representation may be one or more of (i) stored into a designated memory location of memory  1017   n , (ii) transmitted to an external spaced apart device, or (iii) displayed on LCD  1020 . This mode may be used to capture, for example an image of a signature or damage to a package. 
         [0027]    In an image capture operation, the image signal generation system  1028  may be operated in two distinct stages: aiming and final capture. During the aiming stage, frames output by the image signal generation system  1028  are displayed on the LCD display  1020 . These frames are not saved. Once a user is satisfied with the content of the image displayed on the LCD display  1020 , he or she initiates the final capture stage. In final capture stage, a frame (either the frame currently in the buffer or a next frame) is saved and typically displayed on the LCD  1020 . Generally, the aiming stage is initiated by pressing a designated button (such as a scan button  1036 ) with the final capture stage being initiated by releasing the designated button. It is generally desirable to display frames as quickly as possible in the aiming stage to ensure that the user is viewing a recently outputted fame. Otherwise there is a danger that the frame the user views when deciding to initiate capture is outdated and does not accurately reflect what the image signal generating system  1028  is currently outputting (and what will be captured in final capture stage). 
         [0028]    The RFID reader unit  1030  includes an RF oscillation and receiver circuit  1032   a  and a data decode processing circuit  1032   b . RFID reader unit  1030  may be configured to read RF encoded data from a passive RFID tag, such as tag  1051   b , which may be disposed on article  1050 . 
         [0029]    Where the RFID reader unit  1032   a  is configured to read RF encoded data from a passive RFID tag, the RF oscillation and receiver circuit  1032   a  transmits a carrier signal to the passive tag which in turn converts the carrier energy to voltage form and actuates a transponder (not shown) to transmit a radio signal representing the encoded tag data. The RF oscillator and receiver circuit  1032   a , in turn, receives the radio signal from the tag and converts the data into a digital format. The data decode processing circuit  1032   b , typically including a low cost microcontroller IC chip, decodes the received radio signal information received by RF oscillator and receiver circuit  1032   a  to decode the encoded identification data originally encoded into RFID tag. 
         [0030]    RFID reader unit  1030  may, for example, operate in a selective activation mode or in a continuous read operating mode. In a selective activation mode, RFID reader unit  1030  broadcasts radio signals in an attempt to activate a tag or tags in its vicinity in response to an RFID trigger signal being received. In a continuous read mode, RFID reader module  1030  continuously broadcasts radio signals in an attempt to actuate a tag or tags in proximity with unit automatically, without module  1030  receiving a trigger signal. PDT  1000  may be configured so that the CPU  1010  recognizes a trigger signal under numerous conditions, such as: (1) the trigger  1034  is actuated; (2) an RFID trigger instruction is received from a remote device; or (3) the CPU  1010  determines that a predetermined condition has been satisfied. 
         [0031]    Still further, the PDT  1000  may include a card reader unit  1040  for reading data from a card  1052 . Card reader unit  1040  generally comprises a signal detection circuit  1042   a  and a data decode circuit  1042   b . In operation, the signal detection circuit  1042   a  detects data from, for example, a magnetic strip  1053  on a card  1052 . Subsequently, the data decode circuit  1042   b  decodes the data. The decoded data may be transmitted to the CPU  1010  for further processing via the FPGA  1022 . The card reader unit  1040  can be selected to be of a type that reads card information encoded in more than one data format. For example, the card reader unit  1040  may comprise a Panasonic ZU-9A36CF4 Integrated Smart Reader capable of reading any one of magnetic stripe data, smart card or Integrated circuit card (IC card) data, and RF transmitted data. 
         [0032]    A power circuit  1100  supplies power to the PDT  1000 . The power circuit  1100  generally comprises a series of power supplies  1102   n  that regulate the power supplied to the various components of the PDT  1000 . The power supplies  1102   n  each generally comprise step up or step down circuits which are in turn connected to each of the various components in the PDT  1000  that require the particular voltage output by that power supply  11027 . 
         [0033]    The power supplies receive current from a power bus  1103  which is, in turn, supplied by one of a battery  1104 , a first power input  1106  or a connector  1108  that includes a second power input. The first power input  1106  may comprise a DC power jack, for example, a 2.5 mm coaxial DC power plug which receives 9.5 volts from a conventional AC/DC transformer. The connector  1108  may comprise any number of known connection technologies, such as the D Series of circular plastic connectors or the HCL D-sub derivative design data transfer connector available from HYPERTRONICS, INC. Certain pins of the connector  1108  may be dedicated to receiving DC power, for example 9.5 volts, while other pins are dedicated to one or more communication paths, e.g. RS-232 and USB. It may also prove advantageous to provide DC power out, for example from a power supply  1102   a , so as to power tethered accessories, such as external magnetic stripe or RFID readers (not shown). It may prove further advantageous to add circuitry to insulate the first power input  1106  from the second power input on the connector  1108  and other components in the PDT  1000  in the event that a user attempts to supply power to both power inputs. 
         [0034]    The battery  1104  may be selected from any of a variety of battery technologies including fuel cell, NiMh, NiCd, Li Ion, or Li Polymer. The battery  1104  is charged by a charge circuit  1110  which receives power from either the first power input  1106  or the second power input on the connector  1108 . The charge circuit may comprise any of a number of available circuits. In the example shown in  FIG. 2 , control is provided to the CPU  1016  which may modify the charging behavior of the charge circuit  1110  based on information generated by the auxiliary processor  1024 . In this example, the auxiliary processor  1024  monitors battery chemistry, such as gas content, via known interfaces, such as the SMART battery interface as specified by the Smart Battery System Implementers Forum. A switch  1112  isolates the battery based upon the presence of power from the first power input  1106  or the second power input on the connector  1108 . Thus, when an external power supply is connected to the power input  1106  or the second power input on the connector  1108 , the battery is isolated from the power supplies  1102   n  and may be charged via the charge circuit  110 . Once power is removed from the power input  1106  and the connector  1108 , the battery is connected to the power supplies  1102   n.    
         [0035]    The PDT  1000  may further include a plurality of wireless communication links such as an 802.11 communication link  1260 , an 802.16 communication link  1262 , a communication link  1264  for communication with a cellular network such as a network in accordance with the Global System for Mobile Communications (GSM), an IR communication link  1268 , and a Bluetooth communication link  1270 . Each of these links facilitates communication with a remote device and may be used to transfer and receive data. 
         [0036]    The PDT  1000  has an associated biometric sensor  2002  to confirm the identity of a patient. The term “biometrics” generally refers to automated methods of recognizing a person based on a physiological or behavioral characteristic. Among the characteristics that may be measured include; facial features, fingerprints, hand geometry, handwriting iris, retinal, vein, and voice. As such, the biometric sensor  2002  may comprise a finger print reader, an infrared imager, a microphone, a DNA analysis unit or a chemical analysis unit. It is to be noted that the image signal generating system  1028  may also be used as a biometric sensor by obtaining images of body parts, e.g. face, ear, retina, hand, profile, etc . . . While not technically under the definitional umbrella of the term, should the patient be implanted with an RFID chip, the RFID reader unit  1030  may be used as a characteristic to identify the patient. 
         [0037]    A biometric template generally comprises a digital representation of a patient&#39;s distinct characteristics as sensed by the biometric sensor. Biometric templates are formed by transforming the raw output of a sensor using known signal processing techniques which vary depending on the modality of the biometric characteristic sensed. The signal processing techniques may be integrated with the biometric sensor  2002  or may be performed by the CPU  1010  or other processors, such as the auxiliary processor  1024 , within the PDT  1000 . 
         [0038]    Once created, the biometric template is stored in a memory location within the PDT  1000 . Depending upon how the template is to be used (registration, verification or identification) the biometric template is subject to additional processing. In the case of registration, wherein the template is to be associated with a particular person, and used for future verification or identification, identification information is associated with the template and the package is stored in a secure location. This location may be a remote system or somehow secured within the PDT  1000 . If the template is to be used for verification, the PDT  1000  would pull an identified pre-existing template (perhaps from a remote system) and compare the two templates to verify the claimed identity of the person. If the template is to be used for identification, the newly created template would be compared against a pre-existing set of templates to identify the template (and therefore the corresponding person) that most closely matches the newly created template. In general, most PDTs are capable of performing verification where a single comparison operation is required, but many may prove unacceptably slow for identification where multiple comparison operations are required. As such it may prove beneficial to transmit the template that needs identification to a remote system on which the identification comparison processes are carried out. 
         [0039]      FIG. 3  is a flow chart of a method that may be utilized by the described embodiments of the present invention. The method starts in step  300 . In step  302 , an initial biometric scan is performed on a patient. The biometric scan may be performed by any capable device, including the biometric sensor  2002  associated with a PDT  1000 . Next in step  304 , a biometric template is created from the data obtained during the biometric scan. Thereafter in step  306 , the biometric template is associated with the patient. This generally comprises data that identifies the biometric template as describing the patient. This may, for example, comprise an entry in the patient&#39;s medical records pointing to the biometric template. By way of another example, the identity of the patient may be stored in metadata associated with the biometric template. 
         [0040]    Next in step  308 , the biometric template is stored in a defined location. The basic requirement for the location is that it be directly or indirectly accessible by the PDT  1000 . The location will generally fall into three categories: on the PDT  1000 ; in a central database; or in a distributed manner. 
         [0041]    The biometric data may be stored on any of the fixed or removable memory types available to the PDT  1000 , including RAM  1017   a , and FLASH memory  1017   b . While this solution may be suitable for a limited number of patients, it may not be ideal for a large group. It may prove preferable to either centralize storage or distribute storage of the biometric data while supplying the PDT  1000  with one or more patient&#39;s biometric data as needed. The biometric data may be protected by any number of encryption and/or digital rights management schemes. 
         [0042]    A central database will generally comprise one or more computers with associated storage. Using one of the several available communication mediums, the PDT  1000  would transmit and receive biometric templates as needed. U.S. Pat. No. 6,820,050, incorporated herein by reference, discloses a system adapted for use in a hospital environment that may be expanded to include the storage and transmission of biometric templates as part of patient data. In particular, the &#39;050 patent discloses a system wherein patient records are retrieved based upon an identity of a logged-in user. 
         [0043]    The biometric data may also be stored in a distributed manner, meaning that the biometric data for each patient or group of patients may be stored separately. In one possible configuration, the biometric data for a patient may be stored on a device physically associated with the patient, such as a smart card. As another example, a compact flash memory card, such as an SD or Compact FLASH card, may be created for each patient and stored with the patient&#39;s paper records—typically held together by a clip board that may be stored at the nurses station the patient&#39;s bed or just outside his room. By way of yet another example, the biometric data may be encoded into a bar code or RFID tag and affixed to the patient&#39;s wrist. A suitable bar code system is described in U.S. patent application Ser. No. 11/173,228 filed Jun. 30, 2005, assigned to the assignee of the present application, and incorporated herein by reference. Similarly, a suitable RFID system is described in U.S. patent application Ser. No. 11/565,881 filed Dec. 1, 2006, assigned to the assignee of the present application, and incorporated herein by reference. 
         [0044]    After the biometric data is stored (and optionally associated with the patient), the method waits until interaction with a patient is required in step  310 . Such interaction may, for example, comprise providing medication, performing a medical procedure, or simply updating the patient&#39;s vitals chart. Until verification has been performed the person visually identified as requiring such interaction is the suspected patient. 
         [0045]    In step  312 , the biometric template for the patient for which verification is required is retrieved and stored on the PDT  1000 . The PDT  1000  is then used to obtain biometric scan data directly from the suspected patient in step  314 . Thereafter, in step  316 , the scanned biometric scan data is used to create a biometric template for the suspected patient. Next in step  318 , the biometric template from the suspected patient is compared to biometric template of the patient retrieved in step  312 . In  320  a correlation between the two biometric templates is outputted on the PDT  1000 &#39;s screen. The method ends in step  322 . 
         [0046]    Once confirmation is made that the suspected patient is, in fact, the patient, the interaction with the patient may proceed. e.g. the medicine dispensed, the procedure undertaken, etc . . . . If the biometric template from the suspected patient does not match the stored biometric template, a variety options are available, including re-scanning the suspected patient and/or refusing to provide the prescribed medical services 
         [0047]    Although some embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the claims and their equivalents.