Patent Application
20240041649
This disclosure relates to an eye spray apparatus for the self-application of a mist or drops to a user's eye. The apparatus includes a concave mirror for viewing the eye and on-axis, light-guided user alignment features.
Aligning an eyedropper with the eye can be very difficult and challenging. This is typically done on a trial-and-error basis, with the user holding the dropper over the eye, applying the drops, and adjusting position when the drop misses the target. While this might be acceptable for some eyedropper applications, e.g., saline solution or other over-the-counter eye treatments for dry eyes, red eyes, etc., it can be unacceptable for medications, which can be expensive and can require a precise application, e.g., at the center of the eye.
Some solutions for aligning eyedroppers with the eyes have been developed. For example, some eyedroppers include added mirrors that allow the user to view his/her eye while applying the drops. This solution, however, is not as simple as it would seem, as enabling the user to view the dropper while, at the same time, positioning it properly relative to the eye, is complicated. For many of these devices, the addition of the mirror requires the view being off-axis with the dropper nozzle so that the user's view of the mirror is not blocked by the nozzle. As a result, the user is required to exercise some degree of estimation or approximation in directing the drops to the desired location on the eye. As a result, despite the addition of the mirror, alignment issues persist and alignment remains difficult for the user. In fact, one might argue that using the mirror is more complicated and error-prone than simply viewing the nozzle directly.
Existing eyedropper designs are largely gravitationally based with mirror arrangements that require the user to estimate angles and distances to understand where the eye drop will actually land. Additionally, these mirrors tend to be flat, so older users with presbyopia, having a very far (>50 mm) near point in their focal range, the image will still be blurry and out of focus during use.
Implementing a curved mirror to provide some focus magnification and improved details is possible. Mirrors of this sort do, however, tend to be large. For older patients who must wear scleral contact lenses due to corneal abnormalities, accommodation gets weak as they age and they may need higher curvature mirrors with high magnification in close range. With the large curvature of mirror image devices, the virtual image of the eye is magnified and can be extended further out to allow for patients with presbyopia to see their own eyes in clear focus. While the image of the eye is in focus it is not optimized for both nearsighted and farsighted cases and is not optimized for use with an eyedropper. Thus there is a question of what curved mirror focal length is best for a wide variety of near and far sided users while, at the same time, allowing the device to be positioned close enough to effectively apply the eyedropper dose.
An additional problem with these devices lies with the fact that they are traditionally edge lit with light rings that extend around the periphery of the mirror. For a dropper device that must be positioned close to the eye, there needs to be some central illumination. As the device moves closer and closer to the eye surface, however, the peripheral ring lighting is working more and more at an angle, so its effectiveness is increasingly reduced. For a horizontal eye sprayer, the optimal distance between the mirror and the surface of the eye is only about 20-30 mm. As the mirror gets closer and closer to the eye, higher and higher power LEDs are required to provide the necessary degree of illumination from the shallow angle between the light ring and the target.
Horizontal eye sprayers can place the tip of the eye spray nozzle at the center of a concave mirror. This configuration aids in on-axis alignment of the nozzle with the eye. An example of this arrangement is shown in the now expired patent U.S. Pat. No. 3,640,274 A (1969). This arrangement can, however, be problematic. Configuring the nozzle to protrude from the center of the mirror leads to the possibility of error. If the nozzle axis of alignment and mirror optical axis of alignment are off by even a few degrees (e.g.) ±4°, the drops can miss the target. This is especially true in the vertical direction, as the eyelids are typically open only about −7 mm. Therefore, care must be exercised to ensure that the optical axis and the spray axis are coincident and parallel. Additionally, it is better from a reliability standpoint to have the nozzle to be positioned behind, and discharge through, a hole in the mirror. This way, the nozzle can be at least partially sheltered from outside dust or debris.
An eye sprayer includes a spray nozzle having a nozzle axis. the spray nozzle is configured to produce eye spray. The eye sprayer also includes a concave mirror with an opening configured to allow for the delivery eye spray from the spray nozzle. The eye sprayer further includes a light emitter configured to produce a visible light beam directed from the mirror along the nozzle axis.
According to one aspect, the opening in the mirror can include a series of slits, and the spray nozzle can include a series of nozzles. A nozzle can be positioned centrally in each slit. The light emitter can be configured to produce a light beam emitted through each slit.
According to another aspect, the eye spray can include at least one of drops, a mist, and a micro-sheet of eye drop fluid.
According to another aspect, a central axis of the mirror and the nozzle axis can be coincident and parallel.
According to another aspect, the light emitter can be is configured to direct the light through the spray nozzle along the nozzle axis.
According to another aspect, the eye sprayer can be configured to allow the user to view his/her eye at a prescribed working distance. The eye sprayer can also be configured to align the spray nozzle by aligning the image of their own eye with a view of the light source overlaid on top of it.
According to another aspect, the mirror can be configured to have a radius of curvature (ROC) configured to produce a degree of magnification that allows users with myopia or hyperopia/presbyopia to view his/her eye with the eye sprayer positioned at a prescribed working distance.
According to another aspect, the mirror can have a radius of curvature of 55±2 mm, a working distance of 25 mm. According to another aspect, the mirror can have a radius of curvature of 67±2 mm, a working distance of 30 mm.
According to another aspect, the mirror can be an interchangeable insert, and its radius of curvature can be chosen to allow optimal focus position based on the user eye prescription.
According to another aspect, the mirror can have a radius of curvature configured to allow the user to view his/her eye with sufficient clarity and lack of blurriness to allow them to align the view his/her eye with the eye sprayer positioned at a prescribed working distance.
According to another aspect, the mirror can be configured to accommodate users with myopia of at least −6D or hyperopia/presbyopia of at least +3D.
According to another aspect, the mirror can be semi-transparent and can allow viewing additional light sources located behind the mirror to aid alignment.
According to another aspect, the mirror can have a semi-transparency of about 30% transmission about 70% reflectivity.
According to another aspect, the light emitter can include a light ring concentric with the mirror and extending around the nozzle.
According to another aspect, the eye sprayer can also include a proximity sensor configured to determine the proximity of the sprayer to the eye and to produce a visual indication of the sprayer being inside or outside a prescribed range of working distances.
According to another aspect, the mirror can be semi-transparent and the proximity sensor can detect the proximity of the sprayer to the eye through the mirror.
According to another aspect, the proximity sensor can include an ultrasonic proximity sensor, a light-based position sensor, or a camera-based position sensor.
According to another aspect, the opening in the mirror can include a series of slits, and the light emitter can be configured to produce a light beam emitted through each slit. The spray nozzle comprises a series of nozzles, with a nozzle being positioned centrally in each slit.
Referring to
For example, if the nozzle is positioned about 25 mm away from the eye, and the drop diameter is 1.5 mm, there is only +/−2.0 mm of variation in aiming for the drop to hit the eye without hitting the eyelid. This translates into very precise angular requirements. To Further illustrate this point, assuming the eye spray nozzle 30 is perfectly concentric with the mirror 20, an angular deviation of only arctan( 2/30) or +/−4.5 degrees means even a perfectly centered image of the eye in the concave mirror would mean the edge of the drop would hit the eyelid. If the user has problems holding the dropper steady or the mirror isn't exactly concentric with the eye in terms of X-Y lateral displacements, the angular alignment requirements only get tighter. For any particular light path, any mechanical deviation due to mirror offsets in angle or X-Y displacement offsets can be corrected for by the user.
Proper alignment between the nozzle 30 and the eye is a function of two requirements: 1) that the nozzle(s) 30 is/are at the proper distance from the eye, and 2) that the nozzle(s) is/are aimed properly toward the target on the eye surface. To help achieve these requirements, the light source 40 is configured so that light from the individual LEDs passes directly through the nozzle 30 or in the area of the nozzle, in a manner such that the emitted light is aligned with the central spray axis 32. In this configuration, the geometry of the nozzle(s) 30 can be configured to limit the angular deviation of the light beam passing therethrough. By configuring the light source 40 to work in combination with distance/proximity sensing, the proper nozzle distance and dropper/spray trajectory can be achieved.
In the example configuration of the eye sprayer 10 shown in
The mirror is configured to extend across a plane defined by an X-Y axis of the eye sprayer, with the nozzle axis 32 pointing perpendicularly along a Z-axis. The nozzle 30 can be configured to deliver eye spray fluids in the form of drops, mist, micro-sheet, or any other form. Although a single nozzle 30 is shown in
Components internal to the eye sprayer 50 are illustrated schematically in
A series of light openings 42 in the mirror 20, in the form of an array of spaced slits, are positioned adjacent to and on opposite sides of the nozzle 30, with the illumination sources 40 positioned behind. Other shapes, configurations, and arrangements of light openings can be implemented. The pushbuttons 60 can control the operation of the light source 40 and the fluid mover 49.
In one example configuration, the fluid mover 49 can be a pump 50. In this configuration, the pump 50 can be controlled electronically by the controller 54, which supplies power to the pump from the battery 56 in response to inputs from the pushbuttons 60. In an alternative configuration, the pump 50 can be manually operated and the pushbutton 60 for operating the pump is a manually operated mechanical input, such as a trigger. This alternative configuration would be similar to a standard spray bottle configuration.
In another alternative configuration, the fluid mover 49 can be an ejector 51, including an ejection chamber 53 and an actuator 55. In one example configuration, the actuator 55 can be an electromagnetic actuator such as a bi-stable solenoid actuator. The actuator 55 actuates (e.g., pushes) a deformable membrane attached to or formed as a component of the ejection chamber 53. When the actuator 55 is actuated, the membrane deflects and deforms, which causes the fluid to be expelled from the ejection chamber 53, out of the ejector 51 to the nozzle 30. In the example solenoid configuration, this allows for pushing fluid out of the nozzles 30 from the ejection chamber 53 when the solenoid 55 is activated, for example, to an extended state. After ejection, the ejector 51 can also be configured to draw fluid back into the ejection chamber 53, for example, with the membrane drawing new fluid from the reservoir 52 into the ejection chamber in response to the actuator/solenoid 55 returning to a retracted state.
In the example configuration illustrated in
The light sources 40 can be configured to indicate proper positioning near/far distancing of the eye sprayer 10 relative to the eye. To do so, the eye sprayer 10 can include a proximity sensor 62 for sensing the distance between the sprayer and the user's eye. In this instance, the light sources can be configured to provide position feed back to the user. For example, red light can be used to indicate when the distance between the nozzle 30 and the eye is too far or too near, and green light can be used to indicate when the distance between the nozzle and eye is optimized for directing drops or spray from the nozzle into the eye.
In the example configuration of
Referring to
Additionally and advantageously, the user can also judge whether the nozzles 30 are aimed correctly, that is, whether the nozzle axis/axes extend to the target location on the eye 70. Typically the target location will be the center of the eye 70, i.e., the center of the iris/pupil 74. To achieve proper alignment, the user manipulates the position and orientation of the eye sprayer 10 so that the light images 72 coincide with the iris/pupil 74. The light images 72 can be blurred due to being viewed at a close distance, but the image of the eye 70 itself can be magnified by the concave mirror 20 and can be in focus, depending, of course, on the user's vision.
The misalignment scenarios shown in
Referring to
Of course, a combination of the errors shown in
In an alternative configuration of the eye sprayer 10, the mirror 20 is semi-transparent (e.g., 30% transmission 70% reflectivity) to allow for positioning the light sources 40 behind the mirror and transmission of the light through the mirror structure. This can, for example, allow for the light source 40 to be an LED ring light source, concentric with the nozzle axis 32, that allows the user to overlay the image of the light ring with some features of their own eye image, such as edge of the iris or edge of the pupil. The utilization of a semi-transparent mirror can also lend compatibility with other sensors (light based position sensors, camera-based detectors, proximity sensors, etc.) so that the sensor detects the signal through the mirror itself, thus eliminating the need for light openings in the mirror.
The physiology of the eye varies from person to person. For example, nearsightedness (myopia) and farsightedness (hyperopia—lifelong or presbyopia—age related) both affect the user's ability to visualize proper alignment. These issues are exacerbated when considering the utilization of the eye sprayer because its use prohibits the use of corrective lenses, as they would interfere with the delivery of the eye spray fluids. As a result, the user could have difficulty viewing the image of his/her eye in the mirror, which could prevent them from using the eye sprayer. When considering the accommodation range, i.e., the range within which the eye sprayer can be used, the varying degrees of myopia/presbyopia within the population needs to be taken into account. This best visualized in
As shown in
The concave curvature of the mirror 20 will have the effect of magnifying the image of the eye 70. Adjusting the curvature of the mirror thus changes its magnification while, at the same time, changing its focal length. While the working distance is limited by the configuration of the nozzle 30, it is a range, not a fixed distance, and can be taken into account when designing the mirror.
Accordingly, for the eye sprayer 10 disclosed herein, the curvature of the concave mirror 20 is advantageously configured to as to accommodate as large a portion of the population as possible. This is implemented by utilizing an optical ray tracing analysis to choose the optimal curvature based upon world population statistics for both nearsighted and farsighted people.
Through the implementation of an optical model, simulated conditions/results are determined in order to evaluate the efficacy of a particular mirror configuration. The radius of curvature (ROC) of the mirror and the working distance of the mirror are evaluated to determine their effects on users with varying degrees of myopia/presbyopia by simulating what is projected onto the retina. A wide variety of working distance and mirror ROC were simulated to determine the best combinations.
The mirror ROC is chosen so that the user with a given prescription can view the magnified virtual image of their own eye on the mirror 20 with the eye sprayer 10 positioned at a distance comfortable for the user's prescription. The eye sprayer can thereby accommodate users with a wide range of prescriptions. The precise value of the mirror ROC depends on the target eye sprayer working distance range. For example, for a working distance of 25 mm, a mirror ROC of 55±2 mm produces a resulting magnification of ˜8.8×, which can accommodate a range of eyes from myopia −6D to hyperopia +3D. A longer working distance results in a larger optimal ROC and lower magnification. Still, for a working distance of 30 mm, a mirror ROC of 67±2 mm produces a resulting magnification of ˜7.3×, which can also accommodate a range of eyes from myopia −6D to hyperopia +3D. Additionally, the simulation shows the amount of image blur that will be present for the above parameters for users with varying prescriptions at these working distances is not so detrimental as to prevent use of the eye sprayer 10. Nevertheless, the eye sprayer 10 can be configured so that the mirror 20 is interchangeable, with a variety of mirrors configured for different corrective lens prescription ratings being supplied. The user can select and install the mirror 20 best suited for his/her prescription. The eye sprayer 10 can there fore be optimized for that particular user.
Because the eye image is highly magnified by the mirror 20, even in the presence of image blur, alignment can be simple and intuitive. In fact, usability for more severe cases of myopia/hyperopia outside the ranges shown above can be accommodated. Thus, a user with myopia of −7D or worse or one with hyperopia of +4d or worse can be accommodated. In other words, despite the increased image blurriness for these more severe cases, the user can still make out proper alignment and use the eye sprayer effectively.
From the above description, those skilled in the art will perceive improvements, changes, and modifications. These and other such improvements, changes and modifications within the skill of the art are intended to be covered by the appended claims.
This application claims the benefit of U.S. Provisional Application Ser. No. 63/394,645, filed on Aug. 3, 2022, the disclosure of which is hereby incorporated by reference herein in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 63394645 | Aug 2022 | US |
