adjustable focus eyeglasses where the range of adjustment can be moved. That is, if a pair of adjustable focus eyeglasses have a range of 0 diopters to 2.75 diopters (to provide a 2.75 D ADD for reading for an emmetrope), this invention could, for example, permit the user to move the range from 0 D to 2.75 D to 2.00 D to 4.75 D so as to accommodate a short term change in the user's distance vision requirement. Each eye can be adjusted independently.
|
1. Variable Focus Spectacles comprising:
a first pair of lenses, each having a predetermined optical power, each disposed substantially perpendicularly to corresponding left and right optical axes of the variable focus spectacles;
a pair of membrane support structures, each having an opening therein, each of said membrane support structures being associated with and mounted adjacent to and within the field of view of one of said first pair of lenses;
an adjustable connector connecting each of said first lenses to its associated membrane support structure, each said adjustable connector allowing angular motion between its respective first lens and its associated membrane support structure while a connecting distance is held constant, the connecting distance being defined as a distance between a location where the adjustable connector contacts the respective first lens and a location where the adjustable connector contacts the associated membrane support structure, the connecting distance being in a direction substantially parallel to the corresponding optical axis, the adjustable connector further allowing adjustment of the connecting distance;
a transparent membrane attached to each of said membrane support structures across said openings;
a flexible seal extending between each of said first lenses and its associated membrane support structure, said flexible seals permitting motion between said first lenses and their associated membrane support structures; and
liquid having a predetermined index of refraction substantially filling the spaces between each of said first pair of lenses and its associated membrane support structure within its respective seal.
5. Variable Focus Spectacles comprising:
a first pair of lenses, each having a predetermined optical power, each disposed substantially perpendicularly to corresponding left and right optical axes of the variable focus spectacles;
a pair of membrane support structures, each having an opening therein, each of the membrane support structures being associated with and mounted adjacent to and within the field of view of one of the first pair of lenses;
an actuator engaged with each of the membrane support structure at a respective actuation point for changing a distance between the respective first lens and its associated membrane support structure at the actuation point;
an adjustable connector connecting each of the first lenses to its associated membrane support structure, the adjustable connector allowing adjustment of a connecting distance, which is defined as a distance between a location where the adjustable connector contacts the respective first lens and a location where the adjustable connector contacts the associated membrane support structure, the connecting distance being in a direction substantially parallel to the corresponding optical axis, the connector being located at a peripheral location spaced apart from the corresponding actuation point;
a transparent membrane attached to each of the membrane support structures across the openings;
a flexible seal extending between each of the first lenses and its associated membrane support structure, the flexible seals permitting motion between the first lenses and their associated membrane support structures; and
liquid having a predetermined index of refraction substantially filling the spaces between each of the first pair of lenses and its associated membrane support structure within its respective seal.
2. The variable focus spectacles of
3. The variable focus spectacles of
wherein each first lens has a first tab having a first hole,
wherein each membrane support structure has a second tab having a second hole, and
wherein each adjustable connector comprises a screw passing through the corresponding first hole and second hole, the screw having threads operable to engage the first hole or the second hole for adjusting the connecting distance, the screw being loosely fitted in the first and/or the second hole for allowing the angular motion between the respective first lens and its associated membrane support structure while the connecting distance is held constant.
4. The variable focus spectacles of
an actuator having an actuator link engaged with each of the membrane support structure at a respective actuation point for changing a distance between the respective first lens and its associated membrane support structure at the actuation point, wherein the actuation point of each actuator link and the location of the corresponding adjustable connector are spaced apart from each other.
|
Good human vision depends upon properly focusing light incident on the front of the eye onto the retina. To this end the human eye includes an internal lens, and muscles that exert forces on that lens. In youth these muscles can change substantively the focal length of the internal lens, thereby enabling focusing on objects at various distances. With increasing age the ability of these muscles to affect focus decreases until, after about forty-five, most people can no longer focus at both far and near . . . even after any innate hyperopia, or myopia, and/or astigmatism is corrected. Optometrically speaking, people evidencing this condition are called ‘presbyopes’.
Variable focus eyeglasses have been devised that enable a presbyopic wearer manually to adjust focal length, and thereby to focus—on demand—at any distance. See Kurtin, U.S. Pat. Nos. 5,138,494 and 5,668,620 and US Patent Application Publication No. 2008/0084532. The eyeglasses disclosed in the aforementioned patents typically include a) for each eye a fixed optical power equal to the intended wearer's required refractive correction for far vision, together with b) a manually adjustable, bilaterally tracking, spherical ADD power. The maximum ADD can, in some instances, be as large as about 2.75 diopters, which amount is sufficient to permit a change in focus from far viewing to somewhat closer than ‘reading distance’ (usually assumed to be about 16 inches). Emerging presbyopes {those who retain some natural focusing ability} usually require a lesser amount of maximum ADD.
Adjustable focus eyeglasses as just described will suit most presbyopes. Some, however, suffer also from fluctuating vision. This means that the spherical optical power required to correct their far vision varies from time to time (i.e., from hour to hour, or from day to day). Fluctuating vision can arise as a consequence, for example, of diabetes, dry eye, hyperthyroidism, menopause, or possibly other conditions.
While statistically comprehensive information is seemingly not available, published clinical data indicates that in many instances the fluctuation is primarily as to sphere, and can exceed two diopters. More to the point, when an individual with fluctuating vision presents him- or herself for a refraction there is often no conclusive way in which the optometric practitioner can be confident as to i) the relevant range of fluctuation, ii) whether or not that range is static, and iii) where within that range the patient's vision is just then situated. Hence what is needed is eyeglasses which will allow the user, from time to time, to modify his/her spherical refractive correction to offset corresponding biological fluctuations.
This application describes an eyeglass invention which allows its user to update (as to each eye separately), from time to time, his/her spherical refractive correction for far vision. For convenience the invention is described in connection with eyeglasses of the type disclosed in US Patent Application Publication No. 2008/0084532. These previously disclosed glasses are primarily intended for use by conventional presbyopes. The underlying technology can, however, via the invention described herein, be modified to be suitable for i) additionally, or ii) alternatively, compensating for fluctuating vision. Accordingly, the disclosures of that publication are incorporated herein by reference.
For use by presbyopes with fluctuating vision the preferred embodiment disclosed here includes actuator means (located in the bridge of the glasses) whereby bilateral ADD can be adjusted by the user [in addition to, and separately from, the each-eye-separately correction for fluctuating vision which is the subject of this invention]. If the user is not presbyopic it will not be necessary to include this actuator. In any event, said actuator is described in US Patent Application Publication No. 2008/0084532.
The invention can also be applied to other variable focus eyeglasses, but the one discussed herein is the presently preferred embodiment.
The variable lens described in US Patent Application Publication No. 2008/0084532 includes a rigid lens (referred to as the “rear” lens) spaced away from a distensible membrane, the intervening space being filled with a transparent optical liquid. Both the rigid lens and the membrane are held by spaced rings (which, in the preferred embodiment, are circular). A flexible sealing member in the space between the rings keeps the optical liquid from escaping. The inter-ring spacing at a point near the bridge is varied by an actuator located within the bridge, and the inter-ring spacing at a point substantially opposite said point near the bridge is set by a leaf hinge. If said inter-ring spacing near the bridge is changed, a portion of the optical liquid is displaced . . . thereby forcing the membrane incrementally either to bulge or to recede, and correspondingly increasing or decreasing the optical power of the lens. If the portion of the membrane that is free to bulge/recede is circular, and its boundary is flat, the resulting optical power will be essentially spherical.
In the present invention the leaf hinge mentioned above is replaced by a hinge means with controllable axial length (‘H/CAL’) which can be manually set by the wearer. Consequently, as further described below, by setting the axial length of each H/CAL the baseline sphere optical power provided to each eye can be altered in a controlled manner (for example, by up to approximately ±1.4 diopters). Accordingly, said hinge means together with directly related items are sometimes herein called a ‘fluctuating vision compensation mechanism’.
Operation of the fluctuating vision compensation mechanism can be understood as follows: 1) whenever the H/CAL is caused to alter the inter-ring spacing it controls, the volume between the front and rear rings will change correspondingly; 2) the optical liquid, having a constant volume, will thereupon cause the distensible membrane to incrementally bulge or recede; and 3) the baseline optical power of the lens will thereby change [e.g., by up to approximately ±1.4 diopters].
For embodiments including an actuator, the amount of bilateral ADD, as determined by adjusting the actuator and hence by further displacing of optical liquid, will—for both eyes—increment the optical power set by the H/CAL.
Accordingly the invention is expected, for example, to be used as follows:
The invented fluctuating vision compensation mechanism is shown herein as applied to a pair of variable focus spectacles similar to those described in Patent Application Publication 2008/0084532. For convenience, each component that also appears in the patent publication is shown having the same identification number as in that publication, including, in particular, the distensible membrane 22, the transparent optical liquid 16, the actuator link 13, and the tab 11 of the rear ring 20. The link 13, which is a part of the above-mentioned actuator, pushes the tab 11 to accomplish a change of the inter-ring spacing at a point near the bridge as described earlier. Components that are unique to the fluctuating vision compensation mechanism are given numbers over 100.
In this embodiment the mechanisms are attached by means of a front tab 110 and a rear tab 111, welded to the front ring 19 and rear ring 20 respectively. Controllable spacing screw 112 is threaded to match a tapped hole in the front tab, and is turned down at its end to match a hole in the rear tab. This assemblage forms a connector connecting the front ring 19 to rear ring 20. The threads of screw 112 are made somewhat loose, allowing angular motion between the front and rear rings. Retainer 113, welded at the end of controllable spacing screw 112, keeps this screw from coming out of tab 111. Additionally, the thread length of screw 112 is preferably kept short enough that the screw disengages from tab 110 before any interference occurs between the front and rear ring assemblies. And also, as to rotation of the screw in the other direction, the bottom of the screw head 114 bottoms on tab 110 to limit its travel.
As to embodiments with an actuator means, when said actuator is moved the front tab 110 and rear tab 111 move angularly about screw 112 as a pivot; for this reason the screw threads and/or the fit of the screw body into the hole in rear tab 111 must be loose enough to allow adequate unimpeded angular motion. Accordingly it is further preferred that the lens unit be filled such that its internal pressure is positive when the front and rear rings are at their maximum separation.
In the present figures screw 112 is shown at a circumferential location corresponding to the filling location in US Patent Application Publication No. 2008/0084532. Hence, for convenience, in the present invention filling is preferably accomplished by injecting optical liquid through the wall of the sealing member at a somewhat different, but nearby, location. Additionally, since in use the spacing between the front and rear rings (19 and 20) is expected to vary from time to time at each point around the periphery of the lens unit, the bellows 21 preferably has a substantially bellows shape at each section; and hence, unlike as shown in Publication No. 2008/0084532, the sealing member will not have a solid portion at the filling location.
An alternate embodiment of the invention (not illustrated) could be comprised of a flexure [substituted for the leaf hinge in the referenced patent publication], the active length of which is controlled by a slider.
Patent | Priority | Assignee | Title |
Patent | Priority | Assignee | Title |
1269422, | |||
4300818, | Mar 13 1978 | Multifocal ophthalmic lens | |
5138494, | May 07 1990 | Variable focal length lens | |
5440357, | Sep 03 1991 | Lawrence D., Quaglia | Vari-lens phoropter and automatic fast focusing infinitely variable focal power lens units precisely matched to varying distances by radar and electronics |
5526067, | Dec 21 1994 | Lane Research | Actuation mechanism for variable focal length eyeglasses |
5665275, | Nov 28 1990 | Canon Kabushiki Kaisha | Optical device and optical apparatus including same |
5956183, | May 26 1998 | LYCORED NATURAL PRODUCTS INDUSTRIES LIMITED | Field-customizable variable focal length lens |
20080084532, |
Executed on | Assignor | Assignee | Conveyance | Frame | Reel | Doc |
Dec 06 2010 | Zoom Focus Eyewear, LLC | (assignment on the face of the patent) | / |
Date | Maintenance Fee Events |
Date | Maintenance Schedule |
Apr 15 2017 | 4 years fee payment window open |
Oct 15 2017 | 6 months grace period start (w surcharge) |
Apr 15 2018 | patent expiry (for year 4) |
Apr 15 2020 | 2 years to revive unintentionally abandoned end. (for year 4) |
Apr 15 2021 | 8 years fee payment window open |
Oct 15 2021 | 6 months grace period start (w surcharge) |
Apr 15 2022 | patent expiry (for year 8) |
Apr 15 2024 | 2 years to revive unintentionally abandoned end. (for year 8) |
Apr 15 2025 | 12 years fee payment window open |
Oct 15 2025 | 6 months grace period start (w surcharge) |
Apr 15 2026 | patent expiry (for year 12) |
Apr 15 2028 | 2 years to revive unintentionally abandoned end. (for year 12) |