Abstract:
The disclosure relates to finger pulse oximetry sensors configurations including, for example, removable sensor sleeves, removable sensor pads, and light blocking configurations.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of priority from U.S. Provisional Application No. 61/523,161, entitled Fingertip Pulse Oximeter, filed Aug. 12, 2011, which is incorporated in its entirety by reference herein. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    Pulse oximetry is a widely accepted noninvasive procedure for measuring the oxygen saturation level of arterial blood, an indicator of a person&#39;s oxygen supply. A pulse oximetry system consists of a sensor applied to a patient, a monitor, and a patient cable connecting the sensor and the monitor. The sensor is attached to a tissue site, such as a patient&#39;s finger. The sensor has an emitter usually configured with both red and infrared LEDs that, for finger attachment, project light through the fingernail and into the blood vessels and capillaries underneath. Some optical based patient monitors have additional LEDs and can measure other physiological parameters. A detector is positioned at the fingertip opposite the fingernail so as to detect the LED emitted light as it emerges from the finger tissues. There are various noise sources for a sensor including electromagnetic interference (EMI), ambient light and piped light. Light that illuminates the detector without propagating through the tissue site, such as ambient light and piped light, is unwanted optical noise that corrupts the desired sensor signal. Ambient light is transmitted to the detector from external light sources, i.e. light sources other than the emitter. Piped light is stray light from the emitter that is transmitted around a tissue site along a light conductive surface, such as a reflective inner surface of face stock material, directly to the detector. 
         [0003]    Pulse oximetry sensors can be relatively difficult to keep clean and properly sanitize because the internal areas are difficult to reach even with regular cleanings. Over time the sensors begin to build up grime in areas that are difficult to clean. 
         [0004]    Further, when pulse oximeters are dropped, the fragile internal components can be broken or damaged by the impact. Many pulse oximeters have hard plastic housings that transfers the impact directly to the internal components. The impact can damage the components or connectors resulting in erroneous readings, ultimately, forcing medical practitioners to replace the malfunctioning or broken sensors. 
       SUMMARY OF THE INVENTION 
       [0005]    One aspect of the present disclosure includes a pulse oximetry sensor that advantageously provides EMI shielding and optical shielding, including multiple barriers to ambient light. In one embodiment a physiological sensor has a first shell housing including an emitter assembly, a second shell housing having a detector assembly, a first side wall and a second sidewall and a sensor chamber. The sensor chamber is a cavity between the first and second shell housings. The cavity is configured to engage a human finger between the first shell housing and the second shell housing. The first shell housing is coupled to the second shell housing such that it can be manipulated to increase the size of the tissue site to engage a portion of human tissue. The first and second side walls are configured to shield the sensor chamber from ambient light regardless of the position of the first housing and second shell housing relative to each other. 
         [0006]    In another embodiment the sensor has a plastic sleeve having an interior side and an exterior side, wherein the interior side is configured to engage the human finger and the exterior side is configured to engage the sensor chamber. 
         [0007]    In another embodiment the pulse oximeter also has a mounting dock. The mounting dock has a post and a base. The post is sized such that it fits within the sensor chamber and the post is configured to emit UV light within the sensor chamber. 
         [0008]    Another aspect of the present disclosure provides a pulse oximeter with an emitter assembly that decouples from the sensor body. In one embodiment a physiological sensor includes a rigid housing having a top portion, a bottom portion and a sensor chamber. The top portion and the bottom portion are pivotally coupled together. The bottom portion has a detector assembly. The sensor chamber is a cavity between the top portion and the bottom portion of the housing. An emitter assembly is configured to engage the top portion. A flexible linkage is coupled to the emitter assembly and the bottom portion. The linkage is configured to elastically deform such that the emitter assembly can decouple from the top portion of the housing. The emitter assembly is configured to seal the top portion of the housing and shield the sensor chamber from ambient light when coupled to the housing. 
         [0009]    In another embodiment the flexible linkage is an elastomeric material. 
         [0010]    Another aspect of the present disclosure provides a cushioned sleeve for sanitation and comfort for the patient. In one embodiment a fingertip pulse oximeter includes a housing having an emitter assembly, a detector assembly, and a sensor chamber. The sensor includes a sleeve including, a top portion having a first hole and a bottom portion having a second hole. The sleeve is configured to be removably coupled within the sensor chamber. When the sleeve is coupled within the sensor chamber the first hole is configured to correspond to the position of the emitter assembly, and the second hole is configured to correspond to the position of the detector assembly. In some embodiments the sleeve is manufactured from a moldable foam. 
         [0011]    Another aspect of the present disclosure provides shock resistant sensors. In one embodiment a physiological sensor has a sensor housing with a connector interface, and a connector housing surrounding the connector interface. The connector housing forms a cavity between the connector interface and an outer edge of the connector housing. A cable having a cable connector is coupled to the connector interface and the cable connector is at least partially recessed within the connector housing. 
         [0012]    In another embodiment a physiological sensor has a sensor housing made from a rigid material. An internal frame having a plurality of mounting tabs is mounted to the sensor housing. The internal frame is made from a semi-rigid material. A mounting region, is configured to mount a printed circuit board to the plurality of mounting tabs. The frame is configured to absorb force transferred from the sensor housing such that only a portion of the force is transferred to the printed circuit board. In some embodiments the the plurality of mounting tabs are an elastomeric material 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]      FIG. 1  illustrates a perspective view of an embodiment of a pulse oximetry sensor. 
           [0014]      FIG. 2  illustrates a side view of the embodiment of the pulse oximetry sensor from  FIG. 1 . 
           [0015]      FIG. 3  illustrates a side view of the embodiment of the pulse oximetry sensor from  FIG. 1  with a finger inserted within the sensor. 
           [0016]      FIG. 4  illustrates a back view of the embodiment of the pulse oximetry sensor from  FIG. 1  with sensor in the open position. 
           [0017]      FIG. 5  illustrates an embodiment of a finger sleeve. 
           [0018]      FIG. 6  illustrates the embodiment of finger sleeve on a finger prior to being inserted into a fingertip pulse oximetry sensor. 
           [0019]      FIG. 7  illustrates another embodiment of a pulse oximetry sensor in a first position. 
           [0020]      FIG. 8  illustrates the embodiment of the pulse oximetry sensor from  FIG. 7  in a second position. 
           [0021]      FIG. 9  illustrates the embodiment of the pulse oximetry sensor from  FIG. 7  in a third position. 
           [0022]      FIG. 10  illustrates another embodiment of a finger sleeve. 
           [0023]      FIG. 11  illustrates the embodiment of the finger sleeve from  FIG. 10  inserted into an embodiment of a pulse oximetry sensor. 
           [0024]      FIG. 12  illustrates an exploded view of the embodiment of the finger sleeve and pulse oximetry sensor from  FIG. 11 . 
           [0025]      FIG. 13  illustrates an embodiment of a pulse oximetry sensor and an embodiment of a sensor dock. 
           [0026]      FIG. 14  illustrates a plurality of sensor docks coupled together and a plurality of pulse oximetry sensors. 
           [0027]      FIG. 15  illustrates an embodiment of a pulse oximetry sensor with a shock resistant connector housing. 
           [0028]      FIG. 16  illustrates an exploded view of a schematic representation of an embodiment of a pulse oximetry sensor. 
           [0029]      FIG. 17  illustrates an embodiment of an internal frame for a pulse oximetry sensor. 
           [0030]      FIG. 18  illustrates another embodiment of an internal frame for a pulse oximetry sensor. 
           [0031]      FIG. 19  illustrates a perspective view of another embodiment of a pulse oximetry sensor. 
           [0032]      FIG. 20  illustrates a side view of the embodiment of the pulse oximetry sensor from  FIG. 19 . 
           [0033]      FIG. 21  illustrates a side view of the embodiment of the pulse oximetry sensor from  FIG. 19  with a finger inserted within the sensor. 
           [0034]      FIG. 22  illustrates a back view of the embodiment of the pulse oximetry sensor from  FIG. 19  with sensor in the open position. 
           [0035]      FIG. 23  illustrates a perspective view of an embodiment of a pulse oximetry sensor. 
           [0036]      FIG. 24  illustrates a side view of the embodiment of the pulse oximetry sensor from  FIG. 23 . 
           [0037]      FIG. 25  illustrates a side view of the embodiment of the pulse oximetry sensor from  FIG. 23  with a finger inserted within the sensor. 
           [0038]      FIG. 26  illustrates a back view of the embodiment of the pulse oximetry sensor from  FIG. 23  with sensor in the open position. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0039]      FIGS. 1 through 4  illustrate an embodiment of a fingertip pulse oximetry sensor  10 . The sensor  10  is configured to communicate with a base station and is part of a physiological measurement system. A physiological measurement system allows the monitoring of a person, including a patient. In particular, the sensor  10  allows the measurement of blood constituent and related parameters in addition to oxygen saturation and pulse rate. The sensor  10  is adapted to attach to a tissue site, such as a fingertip. In this embodiment, the sensor  10  is incorporated into a reusable finger clip adapted to removably attach to, and transmit light through, a fingertip. In other embodiments, a sensor can be configured to attach to various tissue sites other than a finger, such as a foot or an ear. Also a sensor can be configured as a reflectance or transflectance device that attaches to a forehead or other tissue surface. The sensor  10  has onboard memory that allows it to record the signals monitored from the patient. The sensor  10  has sufficient storage capacity to store at least one night of data, but can store data for longer periods of time depending on the size of the memory and the sample rate of the data. 
         [0040]    The sensor  10  includes a first, or upper, housing  20  that houses a multiple wavelength emitter assembly and a second, or lower, housing  30  that houses a corresponding detector assembly. The first and second housings  20 ,  30  form a tissue cavity  60 . The tissue cavity has an emitter region on the upper housing  20  and a detector region on the lower housing  30 . Alternatively, the emitter region can be in the lower housing  30  and the detector region can be in the upper housing  20 . 
         [0041]    An elastomeric region  40  is connected to the first housing  20  and the second housing  30 . The elastomeric region forms an opening  42  between the housings and the elastomeric member. Preferably the opening  42  is configured such that a lanyard fits through the opening  42 . The upper housing  20  and the lower housing  30  are pivotally coupled together within the housing. The coupling can be a spring or similar apparatus configured such that the upper housing  20  and lower housing  30  can expand and contract relative to each other in order to apply pressure to a fingertip inserted within the cavity  60 . Preferably the pivot point of the sensor  10  is well behind the fingertip, which improves finger attachment and more evenly distributes pressure along the finger. One type of spring assembly is disclosed in U.S. Pat. No. 7,596,398, which is incorporated herein by reference in its entirety. 
         [0042]    The first housing  20  further includes a first outer, or upper, shell  22 , a first upper sidewall  24 , a second upper sidewall  26 , a upper sidewall edge  25 , and an upper cavity wall  27 . The first upper sidewall  24  extends substantially towards the second housing  30 . The upper sidewall edge  25  is substantially perpendicular to the first upper sidewall  24 . The second upper sidewall  26  is substantially parallel to the first upper sidewall  24 . The upper cavity wall  27  defines the upper portion of the of the tissue cavity  60 . In this embodiment the outer shell  22  further includes a plurality of textured regions  28  and an in mold laminate LCD screen  29 . The LCD screen  29  is configured to display parameters that are measured by the sensor. For example the LCD screen  29  can be configured to display pulse rate and oxygen saturation. In some embodiments the upper or lower housing can have a USB connector interface. 
         [0043]    The second housing  30  further includes a second outer, or lower, shell  32 , a lower sidewall  34 , a lower edge  35 , a lower sidewall cavity  38 , and a lower cavity wall  36 . The lower sidewall  34  extends substantially toward the first housing  20 . The lower edge  35  is substantially perpendicular to the lower sidewall  34 . The lower cavity wall  36  defines the lower portion of the tissue cavity  60 . The lower sidewall cavity is a cavity formed in the lower housing  30  between the lower sidewall  34  and the lower cavity wall  36 . The lower cavity  38  is configured such that the second upper sidewall  26  can fit within the cavity  38 . Preferably the cavity  38  is configured such that the second upper sidewall  26  can freely slide in and out of the cavity  38  when the first and second housings  20 ,  30  are manipulated about the pivot point. 
         [0044]    When the sensor  10  is in the closed position, as illustrated in  FIGS. 1 and 2 , the upper sidewall edge  25  and the lower sidewall edge  35  are flush. The second upper sidewall  26  is fully enclosed within the lower cavity  38 . Preferably the first upper sidewall  24  and the lower sidewall  34  have a substantially uniform surface. 
         [0045]    When the sensor  10  is in an open position, as illustrated in  FIGS. 3 and 4 , the upper sidewall edge  25  and lower sidewall edge  35  are separated from each other. The second upper sidewall  26  is at least partially exposed to the environment and ambient light. At least a portion of the second upper sidewall  26  is partially enclosed in the lower cavity  38 . Preferably the second upper sidewall  26  is configured such that it is partially enclosed in the lower cavity regardless of the position of the first and second housings relative to one another. As such the tissue cavity remains closed off from the environment and ambient light regardless of the size of the fingertip inserted within the sensor. Preferably the second upper sidewall  26  is configured such that the sensor  10  such that the sensor  10  lets in the same amount of ambient light regardless of whether the sensor  10  is in an open or closed position. 
         [0046]      FIGS. 5 and 6  illustrate an embodiment of a disposable finger sleeve  70  for use with the sensor  10 . The disposable finger sleeve  70  is a pre-formed finger cover formed of a transparent plastic material for use in a fingertip pulse oximetry sensor. Preferably, the sleeve  70  is a single size that can be universally used by patients regardless of the size of their fingers or the type of fingertip pulse oximetry sensor. Preferably the sleeve  70  is made of a transparent plastic material that does not disrupt or inhibit the operation of the sensor  10 . Preferably the sleeve  70  is placed on the patient&#39;s finger prior to use of the sensor in order to keep the inner surfaces clean and sanitary. Alternatively the finger sleeve can be an opaque material with transparent window to allow operation of the sensor while providing additional shielding from ambient light and light piping. The sleeve can be made of resilient material, such as a hard or semi-hard plastic, such that the sleeve flexes open at the seams of the sleeve so as to conform to the finger, but generally retains its shape. 
       Removable Emitter Assembly 
       [0047]      FIGS. 7 through 9  illustrate another embodiment of a pulse oximetry sensor  100 . In this embodiment the sensor has a first, or upper, housing  150 , a second, or lower, housing  130 , a frame  120 , a tissue cavity (not shown), and a flexible linkage  140 . The flexible linkage has a first end  142  and a second end  144 . The first end  142  is coupled to first housing  120  and the second end  144  is coupled to the second housing  130 . The flexible linkage  140  can be an elastomeric material. The second housing  130  further includes an emitter region or a detector region. 
         [0048]    The first housing  120  further includes a sensor region  122  that can be an emitter or detector region. At least a portion of the first housing  120  is coupled to the flexible linkage  140 . The first end  142  of the flexible linkage  140  is coupled to an end of the first housing  120 . In some embodiments a portion of the first housing  120  can be encased in an elastomeric skin. The elastomeric skin can make up part of the flexible linkage  140 . The first housing  120  is removably coupled to the frame  150 . The first housing  120  includes a means for coupling the first housing  120  to the frame  150 . In this embodiment the first housing  120  has a series of engaging members  124  that mate with similar engaging members on the frame  150 . In other embodiments the first housing can use other means or methods of coupling the first housing  120  with frame  150 . 
         [0049]    The frame  150  is pivotally connected to the second housing  130 . The frame  150  has a series of slots or grooves that allow the first housing  120  to couple with the frame  150 . The frame has a plurality of coupling members (not shown) in order to facilitate the coupling and decoupling of the first housing  120  with the frame  150 . In this embodiment the coupling member are a plurality of slots or grooves (not shown) that matches the engaging members  124  on the first housing  120 . 
         [0050]    Additionally  FIGS. 7 through 9  illustrate a method for coupling the first housing  120  and the frame  150 . Referring specifically to  FIG. 7 , the first housing  120  is illustrated in a first, or locked, position. In the first position the first housing  120  is coupled with the frame  150  and the coupling members are fully engaged with the engaging members  124 . The pulse oximetry sensor is only operated when it is in the first position. Preferably, in the first position, the first housing  129  is coupled with the frame  150  such that the first housing  120  maintains its position during normal operation of the sensor  100 . In some embodiments the first housing can be locked into position using a separate apparatus, such as a latch. 
         [0051]      FIG. 8  illustrates when the first housing  120  is in transition from the first position to a second position. In the transitional position the first housing  120  is manipulated so that it is no longer locked in the first position. Preferably the first housing  120  can be removed from the frame  150  by sliding or manipulating the first housing such that the engaging members  124  are decoupled from the coupling members. The flexible linkage  140  is capable of elastic deformation such that the first housing  120  can be manipulated in order to decouple from the frame without disconnecting the flexible linkage  140  from the second housing  130 . 
         [0052]      FIG. 9  illustrates the sensor  100  in the second position where the first housing  120  has been decoupled from the frame  150 . The first housing  120  remains coupled to the flexible linkage  140  and by extension to the second housing  130 . In the second position the inside of the cavity is exposed. Preferably this allows access to the inside surfaces of the sensor  100 , which would allow a practitioner to properly clean and sterilize the internal surfaces of the sensor  100 , including the emitter region  122  and the detector region. 
       Comfort Fit Finger Cushions 
       [0053]      FIGS. 10 through 12  illustrate another embodiment of a fingertip pulse oximeter  200 . In this embodiment the pulse oximeter sensor  200  has a housing  210 , a sensor sleeve  220 , and an LCD screen  230 . The housing  210  has an outer wall  212  that defines an internal cavity  214 . The internal cavity is configured to house the sensor sleeve  220 . The housing has an emitter assembly and a detector assembly. Either the emitter assembly or detector assembly is on the upper side of the cavity  214 , and the other assembly is on the lower side of the cavity  214 . The LCD screen  230  is configured to display parameters that are measured by the sensor. For example the LCD screen  230  can be configured to display pulse rate and oxygen saturation. 
         [0054]    The sensor sleeve  220  further includes a top portion  222 , a bottom portion  224 , and a fingertip region  226 . The top portion  222  and the bottom portion  224  of the sleeve are connected at a distal end  227  and have a clam shell design that forms the fingertip region  226 . Preferably the sleeve  220  is formed from a single piece of material. The top portion  224  and bottom portion  226  have molded regions  225  that are configured to accommodate a fingertip. The top portion  222  has a first hole  228 . When the sleeve  220  is inserted into the housing  210 , the first hole  228  is configured to align with the emitter assembly of the housing  210 . The bottom portion also has a second hole (not shown) that is aligned with the detector assembly when the sleeve  220  is inserted in the housing  210 . The first hole  228  and second hole allow light to pass through and are configured such that the emitter assembly of the sensor can properly transmit data to the detector assembly of the housing. In some embodiments the emitter assembly and detector assembly can be insert molded into the disposable cushion. Preferably, the sensor sleeve  220  is made from a soft pliable breathable material, such as foam. The sleeve material can be made of moldable foam that molds and contours to the patient&#39;s finger, thus providing a more comfortable or custom fit. Preferably the cushion sensor sleeves are disposed of after use and bacterial contamination between patients can be prevented. Different sleeves can be provided of different sizes that can be used to fit a wider range of finger sizes and shapes. 
         [0055]    Preferably, the housing  210  is coupled to a patient cable, which transmits the data back to a physiological measurement system. Alternately, the housing  210  can include memory and/or wireless communication capability in order to store for later retrieval and/or wirelessly transmit data back to a physiological measurement system. The cable portion and housing  210  of the sensor stays clean and can be reused. Preferably the sleeve portion  220  is disposable. Alternatively the housing  210  can include wireless transmission radios to wirelessly transmit data. 
       UV Light/Modular Charging Base Station 
       [0056]      FIGS. 13 and 14  illustrate an embodiment of a pulse oximeter dock  80 . The dock has a post  82  and a base  84 . The post  82  has a light source for emitting UV light. The light source can emit light in all directions from the post  82 . Preferably the dock  80  acts as charging station for the pulse oximetry sensor  10 . The base  84  is configured such that it can be coupled with other bases  84 , such that multiple docks  80  can be coupled together. 
         [0057]    The UV light source can be used to clean the inside of the pulse oximeter  10 . UV light can efficiently kill bacteria in areas that are difficult to clean and access. Preferably, dock  80  also serves as a charging station for the sensor  10 . For example, the dock  80  can be configured to charge a lithium ion or other rechargeable battery. Preferably the post  82  is sized and shaped such that the sensor  10  can be easily coupled and decoupled from the post. 
         [0058]    A plurality of docks  80  coupled together can be used to provide a convenient location for medical personnel to charge and check out pulse oximeters  10  for patients. The charging dock can also include such features as wireless connectivity to a base station. In situations where there is not a large amount of space to accommodate a full size patient monitor, the charging and connectivity portions of the dock can be split into two parts. One part consists of the main box which contains all of the processing components such as the PCBs, modules, batteries, etc. The other part is a simplified dock that can charge the handheld instrument and serves as a connectivity hub. Since the main box can be quite large, this portion can be placed away from the bedside area so that it does not take up essential real estate near the bedside. The smaller dock can be placed near the bedside. This serves as the main point of interface where a hand held device or tablet device resides. In addition the docking station can be mounted to using a mounting bracket, which can be attached in a convenient location near the bedside. The main box is the larger box and can be placed in a non-essential area of the room, which allows for more real estate near the bedside. 
         [0059]    In some embodiments the dock portion can be transported with the patient cables. Generally the patient cable is wrapped around the unit itself or the cables are stuffed inside the handle opening, which can make it difficult to carry the instrument as well as manage the patient cable. Preferably the handle of the dock can extend outward, in a telescoping manner. The patient cords can be wrapped around the neck of the handle. The handle can be pushed in so that it is flush with the outer surface of the dock when it is not in use. 
       Shock Resistant Connector Housing 
       [0060]      FIG. 15  illustrates another embodiment of a fingertip pulse oximetry sensor  300 . In this embodiment the sensor includes a sensor housing  320 , a connector housing  340 , and an LCD screen  330 . A connector interface  344  is configured to couple with a cable connector  342 . The cable connector can be for a cable connected to a physiological measurement system, a power cable, a data cable, or any other cable used for the operation of a sensor. The connector housing  340  surrounds the connector interface  344 , such that it creates a cavity between the connector interface  344  and the outer edge  346  of the housing  340 . The connector interface  344  is recessed within the connector housing  340 , such that the cable connector  342  is surrounded by the connector housing  340  when the cable is coupled to the sensor  300 . Preferably there is a gap between the connector  342  and the connector housing  340  when the connector  342  is coupled to the sensor  300 . The connector housing  340  can be constructed from a rigid or semi rigid material. In some embodiments the connector housing  340  can be constructed from an elastomeric material. 
         [0061]    The connector housing  340  protects the cable connector  342  from possible damage to the connector in case the sensor is dropped or subject to an impact force. Generally, the sensor has a high probability that it may fall on the floor with the connector  342  inserted into the interface  344 . Generally devices have a fully exposed connector which leaves them susceptible to breaking or damaging if the connector receives a hard impact. The connector housing  340  protects the connector  342  from damage caused by such impact. The connector housing  340  is configured to absorb the force of the impact and minimize the amount of force transferred to the connector  342 , which helps prevent the connector  342  from receiving direct impact that can potentially damage the connector  342 . In some embodiments the sensor housing may have an elastomeric sleeve or other material to help prevent damage to the sensor  300  and connector  342 . 
       Shock Resistant Sensors 
       [0062]      FIG. 16  illustrates a simplified assembly of a pulse oximetry sensor  400 . The assembly includes an first, or upper, housing  420 , an LCD display  410 , a printed circuit board (PCB)  450 , a battery  440 , and a second, or lower, housing  430 . The sensor has delicate components such as the PCB  450 , LCD  410 , and battery  460 . 
         [0063]      FIG. 17  illustrates a cross section of an embodiment of a housing of a pulse oximetry sensor  500 . In this embodiment, the housing has a sensor housing  510 , internal mounting frame  520 , and a mounting region  530 . The internal mounting frame  520  is a semi-rigid rubber structure that surrounds the mounting region  530 . The internal mounting structure has a plurality of internal tabs or ribs  522  in a defined mounting pattern. Preferably the internal tabs  522  are made from the same material as the internal mounting structure  520 . In some embodiments the internal tabs  522  can be made from a softer elastomeric material. The brackets  524  are for mounting the structure  520  to the sensor housing  510 . 
         [0064]    The delicate sensor components, such as the LCD and PCB can be mounted onto the internal tabs  522  in the mounting region  530 . Generally each component would have different mounting patterns. In some embodiments, the frame can have a plurality of tabs configured to account for different mounting configurations. The soft pliable material of the frame  520  can potentially dampen any shock to the sensor  500 . Preferably the frame  520  would be sandwiched between the top and bottom housing which are generally constructed of hard plastic. In some embodiments the top and bottom housing can have an elastomeric sleeve to further dampen the shock to the sensor. 
         [0065]      FIG. 18  illustrates a cross section of another embodiment of a housing of a pulse oximetry sensor  600 . In this embodiment, the housing includes a sensor housing  610  and an internal mounting frame  620 . Preferably the sensor housing  610  is a semi-rigid or elastomeric material. The internal mounting frame  620  is a rigid structure with a plurality of internal tabs or ribs  622  in a defined mounting pattern. The internal tabs  622  are made from an elastomeric material. Preferably the internal tabs  622  are configured to align with the mounting pattern of the mounting component. The sensor housing  610  and the internal tabs  622  can potentially dampen any impact or shock to the delicate components mounted to the frame  620 . 
         [0066]      FIGS. 19 through 22  illustrate another embodiment of a pulse oximetry sensor  700 . The sensor  700  has a first, or upper, housing  720  that houses a multiple wavelength emitter assembly and a second, or lower, housing  730  that houses a corresponding detector assembly. The first and second housings  720 ,  730  form a tissue cavity  760 . The tissue cavity has an emitter region on the upper housing  720  and a detector region on the lower housing  730 . Alternatively, the upper housing  720  has the detector region and the lower housing  730  has the emitter region. There is an opening  742  in the lower housing  730 . The opening  742  can accommodate a lanyard. The upper housing  720  and the lower housing  730  are pivotally coupled together. The coupling can be a spring or similar apparatus configured such that the upper housing  720  and lower housing  730  can expand and contract relative to each other in order to apply pressure to a fingertip inserted within the cavity  760 . 
         [0067]    The first housing  720  has an upper region  727  that partially defines the cavity  760 . The upper region  727  can be contoured to match the shape of a finger, in order provide a more comfortable and snug fit. The upper region  727  can have an elastomeric coating. In this embodiment the first housing  720  further includes a plurality of textured regions  728  and an in mold laminate LCD screen  729 . The LCD screen  729  is configured to display parameters that are measured by the sensor. For example the LCD screen  729  can be configured to display pulse rate and oxygen saturation. In some embodiments the upper or lower housing can have a USB connector interface. 
         [0068]    The second housing  730  has a lower region  736  and an outer, or lower, shell  732 . The lower region  736  partially defines the cavity  760  and can be contoured to match the shape of a finger, in order to provide a more comfortable and snug fit. The lower region  736  can have an elastomeric coating. The outer shell encompasses the second housing  730 . The outer housing has sidewalls  734   a,b  that extend toward the first housing  720  such that the first housing fits between the sidewalls  734 . The sidewalls  734  define a portion of the cavity  760 . The sidewalls are configured to extend substantially beyond the upper portion  727  of the first housing  720  and allow the first housing freedom to be manipulated relative to the sidewalls  734 . The upper housing  720  and lower housing  730  have a plurality of textured grip regions  728 . A user can squeeze the textured grips  728  together to open the sensor  700  and allow for finger placement. 
         [0069]      FIGS. 19 and 20  illustrate the sensor  700  in a closed position.  FIGS. 21 and 22  illustrate the sensor  700  in an open position. The outer shell  732  is configured such that substantially the same amount of ambient light enters the tissue cavity in an open or closed position. 
         [0070]      FIGS. 23 through 26  illustrate yet another embodiment of a pulse oximetry sensor  800 . The sensor  800  has a first, or upper, housing  820  that houses a multiple wavelength emitter assembly and a second, or lower, housing  830  that houses a corresponding detector assembly. The first and second housings  820 ,  830  form a tissue cavity  860 . The tissue cavity has an emitter region on the upper housing  820  and a detector region on the lower housing  830 . Alternatively, the upper housing  720  has the detector region and the lower housing  730  has the emitter region. A loop region  840  forms an opening  842  on the sensor  800 . Preferably the opening  842  is configured such that a lanyard fits through the opening  842 . The upper housing  820  and the lower housing  830  are pivotally coupled together within the housings. 
         [0071]    The first housing  820  further includes a first outer, or upper, shell  822 , a first upper sidewall  824 , a second upper sidewall  826 , an upper sidewall edge  825 , and an upper cavity wall  827 . The first upper sidewall  824  extends substantially towards the second housing  830 . The upper sidewall edge  825  is substantially perpendicular to the first upper sidewall  824 . The second upper sidewall  826  is substantially parallel to the first upper sidewall  824 . The upper cavity wall  827  defines the upper portion of the of the tissue cavity  860 . In this embodiment the outer shell  822  further includes a plurality of textured regions  828  and an in mold laminate LCD screen  829 . The LCD screen  829  is configured to display parameters that are measured by the sensor. For example the LCD screen  829  can be configured to display pulse rate and oxygen saturation. In some embodiments the upper or lower housing can have a USB connector interface. 
         [0072]    The second housing  830  further includes a second outer, or lower, shell  832 , a lower sidewall  834 , a lower edge  835 , a lower sidewall cavity  838 , and a lower cavity wall  836 . The lower sidewall  834  extends substantially toward the first housing  820 . The lower edge  835  is substantially perpendicular to the lower sidewall  834 . The lower cavity wall  836  defines the lower portion of the tissue cavity  860 . The lower sidewall cavity is a cavity formed in the lower housing  830  between the lower sidewall  834  and the lower cavity wall  836 . The lower cavity  838  is configured such that the second upper sidewall  826  can fit within the cavity  838 . Preferably the cavity  838  is configured such that the second upper sidewall  826  can freely slide in and out of the cavity  838  when the first and second housings  820 ,  830  are manipulated about the pivot point. The cavity can be configured to enclose the inner and outer surfaces of the upper sidewall. The cavity can also be configured so that the outer surface of the upper sidewall is in the cavity and the inner surface of the upper sidewall is exposed to the tissue cavity. The upper housing  820  and lower housing  830  have a plurality of textured grip regions  828 . A user can squeeze the textured grips  828  together to open the sensor  800  and allow for finger placement. 
         [0073]    When the sensor  800  is in the closed position, as illustrated in  FIGS. 23 and 24 , the upper sidewall edge  825  and the lower sidewall edge  835  are flush. The second upper sidewall  826  is enclosed within the lower cavity  838 . Preferably the first upper sidewall  824  and the lower sidewall  834  have a substantially uniform surface. 
         [0074]    When the sensor  800  is in an open position, as illustrated in  FIGS. 23 and 24 , the upper sidewall edge  825  and lower sidewall edge  835  are separated from each other. The outer surface of the second upper sidewall  826  is at least partially exposed to the environment and ambient light. At least a portion of the second upper sidewall  826  is partially enclosed in the lower cavity  838 . Preferably the second upper sidewall  826  is configured such that it is partially enclosed in the lower cavity regardless of the position of the first and second housings relative to one another. As such the tissue cavity remains closed off from the environment and ambient light regardless of the size of the fingertip inserted within the sensor. Preferably the second upper sidewall  826  is configured such that substantially the same amount of ambient light enters the tissue cavity in an open or closed position. 
         [0075]    Although certain embodiments, features, and examples have been described herein, it will be understood by those skilled in the art that many aspects of the methods and devices illustrated and described in the present disclosure can be differently combined and/or modified to form still further embodiments. For example, any one feature of the physiological measurement system described above can be used alone or with other components without departing from the spirit of the present invention. Additionally, it will be recognized that the methods described herein may be practiced in different sequences, and/or with additional devices as desired. Such alternative embodiments and/or uses of the methods and devices described above and obvious modifications and equivalents thereof are intended to be included within the scope of the present invention. Thus, it is intended that the scope of the present invention should not be limited by the particular embodiments described above, but should be determined only by a fair reading of the claims that follow.