Patent Description:
These images are produced either with pharmacological pupil dilation, known as mydriatic fundus imaging, or without pharmacological pupil dilation, known as non-mydriatic fundus imaging. Because pupil dilation is inversely related, in part, to the amount of ambient light, non-mydriatic fundus imaging usually occurs in low lighting environments. Medical professionals can also use fundus imaging apparatus to detect or monitor other diseases, such as hypertension, glaucoma, and papilledema.

<CIT> provides an optical image measurement device and method for controlling the same. A low-coherence light is split into a signal light and a reference light. The optical path length of the reference light is switched to optical path lengths that correspond to a first and a second depth zone.

<CIT> provides 3D stereo vision goggles or other platforms that could be used for enhanced vision systems for surgical applications, for patients with macular degeneration, or for entertainment or business applications. The device takes images received from a video input source, and segments and projects those images off a mirror defined by a portion of an ellipsoid and directly onto the retina of the eye of a user.

<CIT> describes systems and methods for providing a line-scanning laser ophthalmoscope (LSLO). The LSLO uses a substantially point source of light, such as an infrared laser or a super-luminescent diode. The point source is expanded to a line. The LSLO scans the line of light in a direction perpendicular to the line across a region of an eye having an undilated pupil. The reflected light is received confocally, using monostatic beam geometry. A beam separator, such as a turning prism or mirror, diverts one of the incoming light and the reflected light to separate the light. An optical stop prevents non-confocally received light from reaching a one-dimensional detector, such as a linear CCD array. An electrical signal responsive to the output light at each of a plurality of locations along the line of output light is processed to provide images of the scanned portion of the eye.

In one aspect, an apparatus for producing a non-mydriatic fundus image according to claim <NUM> is disclosed.

In another aspect, a method for capturing a non-mydriatic image of a fundus according to claim <NUM> is disclosed.

In another aspect, a non-mydriatic image capture system according to claim <NUM> is disclosed.

The following figures, which form a part of this application, are illustrative of described technology and are not meant to limit the scope of the claims in any manner, which scope shall be based on the claims appended hereto.

<FIG> is a schematic block diagram illustrating an example system <NUM> for recording and viewing an image of a patient's fundus. In this example, the system <NUM> includes a patient P, a fundus imaging system <NUM>, a computing device <NUM> including an image processor <NUM>, a camera <NUM> in communication with the computing device <NUM>, a display <NUM> in communication with the computing device <NUM> and used by clinician C, and a network <NUM>. An embodiment of the example fundus imaging system <NUM> is shown and described in more detail below with reference to <FIG>.

The fundus imaging system <NUM> functions to create a set of digital image of a patient's P eye fundus. As used herein, "fundus" refers to the eye fundus and includes the retina, optic nerve, macula, vitreous, choroid and posterior pole.

In this example, one or more images of the eye are desired. For instance, the patient P is being screened for an eye disease, such as diabetic retinopathy. The fundus imaging system <NUM> can also be used to provide images of the eye for other purposes, such as to diagnose or monitor the progression of a disease such as diabetic retinopathy.

The fundus imaging system <NUM> includes a handheld housing that supports the system's components. The housing supports one or two apertures for imaging one or two eyes at a time. In embodiments, the housing supports positional guides for the patient P, such as an optional adjustable chin rest. The positional guide or guides help to align the patient's P eye or eyes with the one or two apertures. In embodiments, the housing supports means for raising and lowering the one or more apertures to align them with the patient's P eye or eyes. Once the patient's P eyes are aligned, the clinician C then initiates the image captures by the fundus imaging system <NUM>.

One technique for fundus imaging requires mydriasis, or the dilation of the patient's pupil, which can be painful and/or inconvenient to the patient P. Example system <NUM> does not require a mydriatic drug to be administered to the patient P before imaging, although the system <NUM> can image the fundus if a mydriatic drug has been administered.

The system <NUM> can be used to assist the clinician C in screening for, monitoring, or diagnosing various eye diseases, such as hypertension, diabetic retinopathy, glaucoma and papilledema. It will be appreciated that the clinician C that operates the fundus imaging system <NUM> can be different from the clinician C evaluating the resulting image.

In the example embodiment <NUM>, the fundus imaging system <NUM> includes a camera <NUM> in communication with an image processor <NUM>. In this embodiment, the camera <NUM> is a digital camera including a lens, an aperture, and a sensor array. The camera <NUM> lens is a variable focus lens, such as a lens moved by a step motor, or a fluid lens, also known as a liquid lens in the art. The camera <NUM> is configured to record images of the fundus one eye at a time. In other embodiments, the camera <NUM> is configured to record an image of both eyes substantially simultaneously. In those embodiments, the fundus imaging system <NUM> can include two separate cameras, one for each eye.

In example system <NUM>, the image processor <NUM> is operatively coupled to the camera <NUM> and configured to communicate with the network <NUM> and display <NUM>.

The image processor <NUM> regulates the operation of the camera <NUM>. Components of an example computing device, including an image processor, are shown in more detail in <FIG>, which is described further below.

The display <NUM> is in communication with the image processor <NUM>. In the example embodiment, the housing supports the display <NUM>. In other embodiments, the display connects to the image processor, such as a smart phone, tablet computer, or external monitor. The display <NUM> functions to reproduce the images produced by the fundus imaging system <NUM> in a size and format readable by the clinician C. For example, the display <NUM> can be a liquid crystal display (LCD) and active matrix organic light emitting diode (AMOLED) display. The display can be touch sensitive.

The example fundus imaging system <NUM> is connected to a network <NUM>. The network <NUM> may include any type of wireless network, a wired network, or any communication network known in the art. For example, wireless connections can include cellular network connections and connections made using protocols such as <NUM>. 11a, b, and/or g. In other examples, a wireless connection can be accomplished directly between the fundus imaging system <NUM> and an external display using one or more wired or wireless protocols, such as Bluetooth, Wi-Fi Direct, radiofrequency identification (RFID), or Zigbee. Other configurations are possible.

<FIG> illustrates components of an example fundus imaging system <NUM>. The example fundus imaging system <NUM> includes a variable focus lens <NUM>, an illumination LED <NUM>, an image sensor array <NUM>, a fixation LED <NUM>, a computing device <NUM>, and a display <NUM>. Each component is in electrical communication with, at least, the computing device <NUM>. Other embodiments can include more or fewer components.

In one of the embodiments, the variable focus lens <NUM> is a liquid lens. A liquid lens is an optical lens whose focal length can be controlled by the application of an external force, such as a voltage. The lens includes a transparent fluid, such as water or water and oil, sealed within a cell and a transparent membrane. By applying a force to the fluid, the curvature of the fluid changes, thereby changing the focal length. This effect is known as electrowetting.

Generally, a liquid lens can focus between about -<NUM> diopters to about +<NUM> diopters. The focus of a liquid lens can be made quickly, even with large changes in focus. For instance, some liquid lenses can autofocus in tens of milliseconds or faster. Liquid lenses can focus from about <NUM> to infinity and can have an effective focal length of about <NUM> or shorter.

In another embodiment of example fundus imaging system <NUM>, the variable focus lens <NUM> is one or more movable lenses that are controlled by a stepping motor, a voice coil, an ultrasonic motor, or a piezoelectric actuator. Additionally, a stepping motor can also move the image sensor array <NUM>. In those embodiments, the variable focus lens <NUM> and/or the image sensor array <NUM> are oriented normal to an optical axis of the fundus imaging system <NUM> and move along the optical axis. An example stepping motor is shown and described below with reference to <FIG>.

The example fundus imaging system <NUM> also includes an illumination light-emitting diode (LED) <NUM>. The illumination LED <NUM> can be single color or multi-color. For example, the illumination LED <NUM> can be a three-channel RGB LED, where each die is capable of independent and tandem operation.

The illumination LED <NUM> is an assembly including one or more visible light LEDs and, optionally, a near-infrared LED. The optional near-infrared LED can be used in a preview mode, for example, for the clinician C to determine or estimate the patient's P eye focus without illuminating visible light that could cause the pupil to contract or irritate the patient P.

The illumination LED <NUM> is in electrical communication with the computing device <NUM>. Thus, the illumination of illumination LED <NUM> is coordinated with the adjustment of the variable focus lens <NUM> and image capture. The illumination LED <NUM> can be overdriven to draw more than the maximum standard current draw rating. In other embodiments, the illumination LED <NUM> can also include a near-infrared LED. The near-infrared LED is illuminated during a preview mode.

The example fundus imaging system <NUM> also optionally includes a fixation LED <NUM>. The fixation LED <NUM> is in communication with the computing device <NUM> and produces a light to guide the patient's P eye for alignment. The fixation LED <NUM> can be a single color or multicolor LED. For example, the fixation LED <NUM> can produce a beam of green light that appears as a green dot when the patient P looks into the fundus imaging system <NUM>. Other colors and designs, such as a cross, "x" and circle are possible.

The example fundus imaging system <NUM> also includes an image sensor array <NUM> that receives and processes light reflected by the patient's fundus. The image sensor array <NUM> is, for example, a complementary metal-oxide semiconductor (CMOS) sensor array, also known as an active pixel sensor (APS), or a charge coupled device (CCD) sensor.

The image sensor array <NUM> has a plurality of rows of pixels and a plurality of columns of pixels. In some embodiments, the image sensor array has about <NUM> by <NUM> pixels, about <NUM> by <NUM> pixels, about <NUM> by <NUM> pixels, about <NUM> by <NUM> pixels, or about <NUM> by <NUM> pixels.

In some embodiments, the pixel size in the image sensor array <NUM> is from about four micrometers by about four micrometers; from about two micrometers by about two micrometers; from about six micrometers by about six micrometers; or from about one micrometer by about one micrometer.

The example image sensor array <NUM> includes photodiodes that have a light-receiving surface and have substantially uniform length and width. During exposure, the photodiodes convert the incident light to a charge. The image sensor array <NUM> can be operated as a global reset, that is, substantially all of the photodiodes are exposed simultaneously and for substantially identical lengths of time.

The example fundus imaging system <NUM> also includes a display <NUM>, discussed in more detail above with reference to <FIG>. Additionally, the example fundus imaging system <NUM> includes a computing device <NUM>, discussed in more detail below with reference to <FIG>.

<FIG> is an embodiment of a method <NUM> for imaging a patient's fundus using a fundus imaging system. In the embodiment shown, the lighting is optimally dimmed prior to execution, although lowering the lighting is optional. The embodiment shown includes a set depth of field operation <NUM>, a set number of zones operation <NUM>, an illuminate lighting operation <NUM>, an adjust lens focus operation <NUM>, a capture image operation <NUM>, repeat operation(s) <NUM>, a show images operation <NUM> and a determine representative image operation <NUM>. Other embodiments can include more or fewer steps.

The embodiment of method <NUM> begins with setting a depth of field operation <NUM>. In embodiments, the variable focus lens <NUM> is capable of focusing from about -<NUM> diopters to about +<NUM> diopters. Set depth of field operation <NUM> defines the lower and upper bounds in terms of diopters. For example, the depth of field range could be set to about -<NUM> to +<NUM> diopters; about -<NUM> to about +<NUM> diopters; about -<NUM> to about +<NUM> diopters; about -<NUM> to about +<NUM> diopters; about - <NUM> to about +<NUM> diopters; or about -<NUM> to about +<NUM> diopters. Other settings are possible. The depth of field can be preprogrammed by the manufacturer. Alternatively, the end user, such as the clinician C, can set the depth of field.

As shown in <FIG>, the next operation in embodiment of method <NUM> is setting the number of zones operation <NUM>. However, zones operation <NUM> can occur before or concurrent with field operation <NUM>. In zones operation <NUM>, the depth of field is divided into equal parts, where each part is called a zone. In other embodiments, the zones are not all equal. The number of zones is equal to the number of images captured in capture image operation <NUM>.

For example, when the depth of field is from -<NUM> to +<NUM> diopters, the focus of the variable focus lens can be changed by <NUM> diopters before each image capture. Thus, in this example, images would be captured at -<NUM>, -<NUM>, -<NUM>, +<NUM>, +<NUM> and +<NUM> diopters. Or, images could be captured at -<NUM>, -<NUM>, <NUM>, +<NUM> and +<NUM> diopters, thereby capturing an image in zones -<NUM> to -<NUM> diopters, - <NUM> to -<NUM> diopters, -<NUM> to +<NUM> diopters, +<NUM> to +<NUM> diopters and +<NUM> to +<NUM> diopters, respectively. In that instance, the depth of focus is about +/- <NUM> diopters. Of course, the number of zones and the depth of field can vary, resulting in different ranges of depth of field image capture.

In embodiments, both depth of field and number of zones are predetermined. For example, -10D to +10D and <NUM> zones. Both can be changed by a user.

After the depth of field and number of zones are set, the next operation in embodiment of method <NUM> is the image capture process, which includes illuminate lighting operation <NUM>, adjust lens focus operation <NUM> and capture image operation <NUM>. As shown in <FIG>, the lighting component is illuminated (lighting operation <NUM>) before the lens focus is adjusted (lens focus operation <NUM>). However, lens focus operation <NUM> can occur before or concurrent with lighting operation <NUM>.

The illumination LED <NUM> is illuminated in lighting operation <NUM>. The illumination LED <NUM> can remain illuminated throughout the duration of each image capture. Alternatively, the illumination LED <NUM> can be turned on and off for each image capture. In embodiments, the illumination LED <NUM> only turns on for the same period of time as the image sensor array <NUM> exposure time period.

Optionally, lighting operation <NUM> can additionally include illuminating a near-infrared LED. The clinician C can use the illumination of the near-infrared LED as a way to preview the position of the patient's P pupil.

The focus of variable focus lens <NUM> is adjusted in lens focus operation <NUM>. Autofocusing is not used in embodiment of method <NUM>. That is, the diopter setting is provided to the lens without regard to the quality of the focus of the image. Indeed, traditional autofocusing fails in the low-lighting non-mydriatic image capturing environment. The embodiment of method <NUM> results in a plurality of images at least one of which, or a combination of which, yields an in-focus view of the patient's P fundus.

Additionally, the lack of autofocusing enables the fundus imaging system <NUM> to rapidly capture multiple images in capture image operation <NUM> at different diopter ranges. That is, variable focus lens <NUM> can be set to a particular diopter range and an image captured without the system verifying that the particular focus level will produce an in-focus image, as is found in autofocusing systems. Because the system does not attempt to autofocus, and the focus of the variable focus lens <NUM> can be altered in roughly tens of milliseconds, images can be captured throughout the depth of field in well under a second, in embodiments. Thus, in the embodiment of method <NUM>, the fundus imaging system <NUM> can capture images of the entire depth of field before the patient's P eye can react to the illuminated light. Without being bound to a particular theory, depending on the patient P, the eye might react to the light from illumination LED <NUM> in about <NUM> milliseconds.

The image sensor array <NUM> captures an image of the fundus in capture image operation <NUM>. As discussed above, the embodiment of method <NUM> includes multiple image captures of the same fundus at different diopter foci. The example fundus imaging system <NUM> uses a global reset or global shutter array, although other types of shutter arrays, such as a rolling shutter, can be used. The entire image capture method <NUM> can also be triggered by passive eye tracking and automatically capture, for example, <NUM> frames of images. An embodiment of example method for passive eye tracking is shown and described in more detail with reference to <FIG>, below.

After the fundus imaging system <NUM> captures an image of the fundus, the embodiment of method <NUM> returns in loop <NUM> to either the illuminate lighting operation <NUM> or the adjust lens focus operation <NUM>. That is, operations <NUM>, <NUM> and <NUM> are repeated until an image is captured in each of the preset zones from zones operation <NUM>. It is noted that the image capture does not need to be sequential through the depth of field. Additionally, each of the images does not need to be captured in a single loop; a patient could have one or more fundus images captured and then one or more after a pause or break.

After an image is captured in each of the zones (capture image operation <NUM>) in embodiment of method <NUM>, either the images are displayed in show images operation <NUM> or a representative image is determined in operation <NUM> and then the image is displayed. Show images operation <NUM> can include showing all images simultaneously or sequentially on display <NUM>. A user interface shown on display <NUM> can then enable the clinician C or other reviewing medical professional to select or identify the best or a representative image of the patient's P fundus.

In addition to show images operation <NUM>, the computing device can determine a representative fundus image in operation <NUM>. Operation <NUM> can also produce a single image by compiling aspects of one or more of the images captured. This can be accomplished by, for example, using a wavelet feature reconstruction method to select, interpolate, and/or synthesize the most representative frequency or location components.

The fundus imaging system <NUM> can also produce a three-dimensional image of the fundus by compiling the multiple captured images. Because the images are taken at different focus ranges of the fundus, the compilation of the pictures can contain three-dimensional information about the fundus.

In turn, the image or images from operation <NUM> or <NUM> can be sent to a patient's electronic medical record or to a different medical professional via network <NUM>.

<FIG> illustrates an embodiment of example fundus imaging system <NUM>. The embodiment <NUM> includes a housing <NUM> that supports an optional fixation LED <NUM>, an objective lens <NUM>, fixation LED mirrors <NUM>, variable focus lens assembly <NUM>, display <NUM>, printed circuit board <NUM>, step motor <NUM>, image sensor array <NUM>, and illumination LED <NUM>. Also shown in <FIG> are light paths L that include potential light paths from optional fixation LED <NUM> and incoming light paths from outside the fundus imaging system <NUM>. The illustrated components have the same or similar functionality to the corresponding components discussed above with reference to <FIG> above. Other embodiments can include more or fewer components.

The housing <NUM> of example fundus imaging system <NUM> is sized to be hand held. In embodiments, the housing <NUM> additionally supports one or more user input buttons near display <NUM>, not shown in <FIG>. The user input button can initiate the image capture sequence, at least a portion of which is shown and discussed with reference to <FIG>, above. Thus, the fundus imaging system <NUM> is capable of being configured such that the clinician C does not need to adjust the lens focus.

Fixation LED <NUM> is an optional component of the fundus imaging system <NUM>. The fixation LED <NUM> is a single or multi-colored LED. Fixation LED <NUM> can be more than one LED.

As shown in <FIG>, pivoting mirrors <NUM> can be used to direct light from the fixation LED <NUM> towards the patient's pupil. Additionally, an overlay or filter can be used to project a particular shape or image, such as an "X", to direct the patient's focus. The pivoting mirrors <NUM> can control where the fixation image appears in the patient's view. The pivoting mirrors <NUM> do not affect the light reflected from the patient's fundus.

The embodiment of example fundus imaging system <NUM> also includes a variable focus lens assembly <NUM>. As shown in <FIG>, the variable focus lens assembly <NUM> is substantially aligned with the longitudinal axis of the housing <NUM>. Additionally, the variable focus lens assembly <NUM> is positioned between the objective lens <NUM> and the image sensor array <NUM> such that it can control the focus of the incident light L onto the image sensor array.

The example printed circuit board <NUM> is shown positioned within one distal end of the housing <NUM> near the display <NUM>. However, the printed circuit board <NUM> can be positioned in a different location. The printed circuit board <NUM> supports the components of the example computing device <NUM>. A power supply can also be positioned near printed circuit board <NUM> and configured to power the components of the embodiment of example fundus imaging system <NUM>.

Step motor <NUM> is an optional component in the example embodiment <NUM>. Step motor <NUM> can also be, for example, a voice coil, an ultrasonic motor, or a piezoelectric actuator. In the example embodiment <NUM>, step motor <NUM> moves the variable focus lens assembly <NUM> and/or the sensor array <NUM> to achieve variable focus. The step motor <NUM> moves the variable focus lens assembly <NUM> or the sensor array <NUM> in a direction parallel to a longitudinal axis of the housing <NUM> (the optical axis). The movement of step motor <NUM> is actuated by computing device <NUM>.

The example image sensor array <NUM> is positioned normal to the longitudinal axis of the housing <NUM>. As discussed above, the image sensor array <NUM> is in electrical communication with the computing device. Also, as discussed above, the image sensor array can be a CMOS (APS) or CCD sensor.

An illumination LED <NUM> is positioned near the variable focus lens assembly <NUM>. However, the illumination LED <NUM> can be positioned in other locations, such as near or with the fixation LED <NUM>.

<FIG> illustrates an alternate embodiment of initiate retinal imaging step <NUM> using passive eye tracking. The initiate retinal imaging step <NUM> operates to image the fundus of the patient P using passive eye tracking. In the initiate retinal imaging step <NUM>, the fundus imaging system <NUM> monitors the pupil/fovea orientation of the patient P. Although the initiate retinal imaging step <NUM> is described with respect to fundus imaging system <NUM>, the initiate retinal imaging step <NUM> may be performed using a wearable or nonwearable fundus imaging system, such as a handheld digital fundus imaging system.

Initially, at step <NUM>, the pupil or fovea or both of the patient P are monitored. The fundus imaging system <NUM> captures images in a first image capture mode. In the first image capture mode, the fundus imaging system <NUM> captures images at a higher frame rate. In some embodiments, in the first image capture mode, the fundus imaging system <NUM> captures images with infra-red illumination and at lower resolutions. In some embodiments, the infra-red illumination is created by the illumination LED <NUM> operating to generate and direct light of a lower intensity towards the subject. The first image capture mode may minimize discomfort to the patient P, allow the patient P to relax, and allow for a larger pupil size without dilation (non-mydriatic).

Next, at step <NUM>, the computing system <NUM> processes at least a portion of the images captured by the fundus imaging system <NUM>. The computing system <NUM> processes the images to identify the location of the pupil or fovea or both of the patient P. Using the location of the pupil or fovea or both in one of the images, a vector corresponding to the pupil/fovea orientation is calculated. In some embodiments, the pupil/fovea orientation is approximated based on the distance between the pupil and fovea in the image. In other embodiments, the pupil/fovea orientation is calculated by approximating the position of the fovea relative to the pupil in three dimensions using estimates of the distance to the pupil and the distance between the pupil and the fovea. In other embodiments, the pupil/fovea orientation is approximated from the position of the pupil alone. In yet other embodiments, other methods of approximating the pupil/fovea orientation are used.

Next, at step <NUM>, the pupil/fovea orientation is compared to the optical axis of the fundus imaging system <NUM>. If the pupil/fovea orientation is substantially aligned with the optical axis of the fundus imaging system <NUM>, the process proceeds to step <NUM> to capture a fundus image. If not, the process returns to step <NUM> to continue to monitor the pupil or fovea. In some embodiments, the pupil/fovea orientation is substantially aligned with the optical axis when the angle between them is less than two to fifteen degrees.

Next, at step <NUM>, fundus images are captured by triggering the embodiment of example thru focusing image capturing method <NUM>. In embodiments, five images are captured at step <NUM>. In some embodiments, the fundus image is captured in a second image capture mode. In some embodiments, in the second image capture mode, the fundus imaging system <NUM> captures images with visible illumination and at higher resolutions. In some embodiments, the visible illumination is created by the illumination LED <NUM> operating to generate and direct light of a higher intensity towards the subject. In other embodiments, the higher illumination is created by an external light source or ambient light. The second image capture mode may facilitate capturing a clear, well-illuminated, and detailed fundus image.

In some embodiments, after step <NUM>, the initiate retinal imaging step <NUM> returns to step <NUM> to continue to monitor the pupil/fovea orientation. The initiate retinal imaging step <NUM> may continue to collect fundus images indefinitely or until a specified number of images have been collected. Further information regarding passive eye tracking can be found in <CIT>, attorney docket number <NUM>. 0082US01, titled Ophthalmoscope Device.

<FIG> is an embodiment of example use <NUM> of fundus imaging system <NUM>. In the embodiment of example use <NUM>, a clinician positions the fundus imaging system (operation <NUM>), initiates image capture (operation <NUM>), positions the fundus imaging system over the other eye (operation <NUM>), initiates image capture (operation <NUM>), and views images (operation <NUM>). Although the example use <NUM> is conducted without first administering mydriatic pharmaceuticals, the example use <NUM> can also be performed for a patient who has taken a pupil-dilating compound. The embodiment of example use <NUM> can also include lowering the lighting. The embodiment of example use <NUM> is conducted using the same or similar components as those described above with reference to <FIG>. Other embodiments can include more or fewer operations.

The embodiment of example use <NUM> begins by positioning the fundus imaging system (operation <NUM>). In embodiments, the clinician first initiates an image capture sequence via a button on the housing or a graphical user interface shown by the display. The graphical user interface can instruct the clinician to position the fundus imaging system over a particular eye of the patient. Alternatively, the clinician can use the graphical user interface to indicate which eye fundus is being imaged first.

In operation <NUM>, the clinician positions the fundus imaging system near the patient's eye socket. The clinician positions the aperture of the system flush against the patient's eye socket such that the aperture, or a soft material eye cup extending from the aperture, seals out most of the ambient light. Of course, the example use <NUM> does not require positioning the aperture flush against the patient's eye socket.

When the fundus imaging system is in position, the system captures more than one image of the fundus in operation <NUM>. As discussed above, the system does not require the clinician to manually focus the lens. Additionally, the system does not attempt to autofocus on the fundus. Rather, the clinician simply initiates the image capture, via a button or the GUI, and the fundus imaging system controls when to capture the images and the focus of the variable focus lens. Also, as discussed above at least with reference to <FIG>, the system can initiate image capture using passive eye tracking.

The patient may require the fundus imaging system to be moved away from the eye socket during image capture operation <NUM>. The clinician can re-initiate the image capture sequence of the same eye using the button or the GUI on the display.

After capturing an image in each of the specified zones, the fundus imaging system notifies the clinician that the housing should be positioned over the other eye (operation <NUM>). The notification can be audible, such as a beep, and/or the display can show a notification. In embodiments, the system is configured to capture a set of images of only one eye, wherein the example method <NUM> proceeds to view images operation <NUM> after image capture operation <NUM>.

Similar to operation <NUM>, the clinician then positions the fundus imaging system near or flush with the patient's other eye socket in operation <NUM>. Again, when the system is in place, an image is captured in every zone in operation <NUM>.

After images have been captured of the fundus in each pre-set zone, the clinician can view the resulting images in operation <NUM>. As noted above with reference to <FIG>, the images can be post-processed before the clinician views the images to select or synthesize a representative image. Additionally, the fundus images can be sent to a remote location for viewing by a different medical professional.

<FIG> is a block diagram illustrating physical components (i.e., hardware) of a computing device <NUM> with which embodiments of the disclosure may be practiced. The computing device components described below may be suitable to act as the computing devices described above, such as wireless computing device and/or medical device of <FIG>. In a basic configuration, the computing device <NUM> may include at least one processing unit <NUM> and a system memory <NUM>. Depending on the configuration and type of computing device, the system memory <NUM> may comprise, but is not limited to, volatile storage (e.g., random access memory), non-volatile storage (e.g., read-only memory), flash memory, or any combination of such memories. The system memory <NUM> may include an operating system <NUM> and one or more program modules <NUM> suitable for running software applications <NUM>. The operating system <NUM>, for example, may be suitable for controlling the operation of the computing device <NUM>. Furthermore, embodiments of the disclosure may be practiced in conjunction with a graphics library, other operating systems, or any other application program and is not limited to any particular application or system. This basic configuration is illustrated in <FIG> by those components within a dashed line <NUM>. The computing device <NUM> may have additional features or functionality. For example, the computing device <NUM> may also include additional data storage devices (removable and/or non-removable) such as, for example, magnetic disks, optical disks, or tape. Such additional storage is illustrated in <FIG> by a removable storage device <NUM> and a non-removable storage device <NUM>.

As stated above, a number of program modules and data files may be stored in the system memory <NUM>. While executing on the processing unit <NUM>, the program modules <NUM> may perform processes including, but not limited to, generate list of devices, broadcast user-friendly name, broadcast transmitter power, determine proximity of wireless computing device, connect with wireless computing device, transfer vital sign data to a patient's EMR, sort list of wireless computing devices within range, and other processes described with reference to the figures as described herein. Other program modules that may be used in accordance with embodiments of the present disclosure, and in particular to generate screen content, may include electronic mail and contacts applications, word processing applications, spreadsheet applications, database applications, slide presentation applications, drawing or computer-aided application programs, etc..

For example, embodiments of the disclosure may be practiced via a system-on-a-chip (SOC) where each or many of the components illustrated in <FIG> may be integrated onto a single integrated circuit. Such an SOC device may include one or more processing units, graphics units, communications units, system virtualization units and various application functionality all of which are integrated (or "burned") onto the chip substrate as a single integrated circuit. When operating via an SOC, the functionality, described herein, may be operated via application-specific logic integrated with other components of the computing device <NUM> on the single integrated circuit (chip). Embodiments of the disclosure may also be practiced using other technologies capable of performing logical operations such as, for example, AND, OR, and NOT, including but not limited to mechanical, optical, fluidic, and quantum technologies.

The computing device <NUM> may also have one or more input device(s) <NUM> such as a keyboard, a mouse, a pen, a sound or voice input device, a touch or swipe input device, etc. The output device(s) <NUM> such as a display, speakers, a printer, etc. may also be included. The aforementioned devices are examples and others may be used. The computing device <NUM> may include one or more communication connections <NUM> allowing communications with other computing devices. Examples of suitable communication connections <NUM> include, but are not limited to, RF transmitter, receiver, and/or transceiver circuitry; universal serial bus (USB), parallel, and/or serial ports.

The term computer readable media as used herein may include non-transitory computer storage media. The system memory <NUM>, the removable storage device <NUM>, and the non-removable storage device <NUM> are all computer storage media examples (i.e., memory storage. ) Computer storage media may include RAM, ROM, electrically erasable read-only memory (EEPROM), flash memory or other memory technology, CD-ROM, digital versatile disks (DVD) or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other article of manufacture which can be used to store information and which can be accessed by the computing device <NUM>.

Although the example medical devices described herein are devices used to monitor patients, other types of medical devices can also be used. For example, the different components of the CONNEX™ system, such as the intermediary servers that communication with the monitoring devices, can also require maintenance in the form of firmware and software updates. These intermediary servers can be managed by the systems and methods described herein to update the maintenance requirements of the servers.

Embodiments of the present invention may be utilized in various distributed computing environments where tasks are performed by remote processing devices that are linked through a communications network in a distributed computing environment.

The block diagrams depicted herein are just examples. There may be many variations to these diagrams described therein without departing from the spirit of the disclosure. For instance, components may be added, deleted or modified.

While embodiments have been described, it will be understood that those skilled in the art, both now and in the future, may make various improvements and enhancements can be made.

As used herein, "about" refers to a degree of deviation based on experimental error typical for the particular property identified. The latitude provided the term "about" will depend on the specific context and particular property and can be readily discerned by those skilled in the art. The term "about" is not intended to either expand or limit the degree of equivalents which may otherwise be afforded a particular value. Further, unless otherwise stated, the term "about" shall expressly include "exactly," consistent with the discussions regarding ranges and numerical data. Concentrations, amounts, and other numerical data may be expressed or presented herein in a range format. It is to be understood that such a range format is used merely for convenience and brevity and thus should be interpreted flexibly to include not only the numerical values explicitly recited as the limits of the range, but also to include all the individual numerical values or sub-ranges encompassed within that range as if each numerical value and sub-range is explicitly recited. As an illustration, a numerical range of "about <NUM> percent to about <NUM> percent" should be interpreted to include not only the explicitly recited values of about <NUM> percent to about <NUM> percent, but also include individual values and sub-ranges within the indicated range. Thus, included in this numerical range are individual values such as <NUM>, <NUM> and <NUM> and sub-ranges such as from <NUM>-<NUM>, from <NUM>-<NUM>, and from <NUM>-<NUM>; etc. This same principle applies to ranges reciting only one numerical value. Furthermore, such an interpretation should apply regardless of the breadth of the range or the characteristics being described.

Claim 1:
An apparatus for producing a non-mydriatic fundus image, comprising:
a processor (<NUM>) and a memory (<NUM>);
an illumination component (<NUM>) including a visible light source and operatively coupled to the processor (<NUM>);
a camera (<NUM>) including a lens (<NUM>) and operatively coupled to the processor (<NUM>); and
a display (<NUM>) coupled to the memory (<NUM>) and to the processor (<NUM>),
wherein the memory (<NUM>) stores instructions that, when executed by the processor (<NUM>), cause the apparatus to:
set a depth of field for capturing a plurality of images of a fundus, the depth of field being set by defining lower and upper diopters;
set a number of zones (<NUM>), wherein the zones are parts in which the depth of field is divided and each zone comprises a diopter range;
adjust a focus of the lens (<NUM>) to each of the plurality of different diopter ranges, the lens being set to each diopter range without regard to focus of features shown by the lens;
capture, using the camera, the plurality of images of a fundus, wherein the camera (<NUM>) captures at least one image within each of the plurality of different diopter ranges;
illuminate, using the illumination component, visible light during the capture of the plurality of images; and
after capturing each of the plurality of images of the fundus:
determine a representative image of the fundus from the plurality of images; and
display the representative image of the fundus.