1. Field
Embodiments of the present invention relate to fluid-filled lenses and in particular to variable fluid-filled lenses.
2. Background Art
Basic fluid lenses have been known since about 1958, as described in U.S. Pat. No. 2,836,101, incorporated herein by reference in its entirety. More recent examples may be found in “Dynamically Reconfigurable Fluid Core Fluid Cladding Lens in a Microfluidic Channel” by Tang et al., Lab Chip, 2008, vol. 8, p. 395, and in WIPO publication WO2008/063442, each of which is incorporated herein by reference in its entirety. These applications of fluid lenses are directed towards photonics, digital phone and camera technology and microelectronics.
Fluid lenses have also been proposed for ophthalmic applications (see, e.g., U.S. Pat. No. 7,085,065, which is incorporated herein by reference in its entirety). In all cases, the advantages of fluid lenses, such as a wide dynamic range, ability to provide adaptive correction, robustness, and low cost have to be balanced against limitations in aperture size, possibility of leakage, and consistency in performance. The '065 patent, for example, has disclosed several improvements and embodiments directed towards effective containment of the fluid in the fluid lens to be used in ophthalmic applications, although not limited to them (see, e.g., U.S. Pat. No. 6,618,208, which is incorporated by reference in its entirety). Power adjustment in fluid lenses has been effected by injecting additional fluid into a lens cavity, by electrowetting, application of ultrasonic impulse, and by utilizing swelling forces in a cross-linked polymer upon introduction of a swelling agent such as water.
In an embodiment, an actuator for a fluid-filled lens comprises: a housing; a reservoir disposed within the housing; a compression arm having a first end that is fixed and a second end that is not fixed, wherein the compression arm is disposed adjacent to the reservoir; and wherein the compression arm flexes to compress the reservoir.
In another embodiment, an actuator for a fluid-filled lens comprises: a housing having a first end and a second end; a reservoir disposed within the housing; and a slider slidingly disposed within the housing and disposed adjacent to the reservoir, wherein the slider includes a first end having a wedge shape configured to compress the reservoir, and wherein sliding of the slider from the second end of the housing to the first end of the housing causes the first end of the slider to compress the reservoir.
Further embodiments, features, and advantages of the present invention, as well as the structure and operation of the various embodiments of the present invention, are described in detail below with reference to the accompanying drawings.
The accompanying drawings, which are incorporated herein and form a part of the specification, illustrate the present invention and, together with the description, further serve to explain the principles of the invention and to enable a person skilled in the pertinent art to make and use the invention.
a illustrates an embodiment of a caliper actuator assembly.
b illustrates an embodiment of a caliper actuator assembly.
a illustrates a side view of an embodiment of a roll and translate actuator assembly.
b illustrates a top view of the roll and translate actuator assembly of
c illustrates a side view of the roll and translate actuator assembly of
a illustrates a side view of another embodiment of a roll and translate actuator assembly.
b illustrates a top view of the roll and translate actuator assembly of
c illustrates a side view of the roll and translate actuator assembly of
b illustrates a front view of an embodiment of a reservoir.
a illustrates a side view of an embodiment of a rack and pinion actuator assembly.
b illustrates a side view of the rack and pinion actuator assembly of
a illustrates a side view of an embodiment of a rack and pinion actuator assembly.
b illustrates a top view of the rack and pinion actuator assembly of
c illustrates a side view of the rack and pinion actuator assembly of
a illustrates a side view of an embodiment of a screw actuator assembly.
b illustrates a side view of an embodiment of a screw actuator assembly when compressed.
a illustrates a side view of an embodiment of a rotation actuator assembly when partially compressed.
b illustrates a view of an embodiment of the rotation actuator assembly of
a along line A.
a illustrates a side view of an embodiment of a slide and translate actuator assembly.
b illustrates a front sectional view of an embodiment of a slide and translate actuator assembly.
Embodiments of the present invention will be described with reference to the accompanying drawings.
Although specific configurations and arrangements are discussed, it should be understood that this is done for illustrative purposes only. A person skilled in the pertinent art will recognize that other configurations and arrangements can be used without departing from the spirit and scope of the present invention. It will be apparent to a person skilled in the pertinent art that this invention can also be employed in a variety of other applications.
It is noted that references in the specification to “one embodiment,” “an embodiment,” “an example embodiment,” etc., indicate that the embodiment described may include a particular feature, structure, or characteristic, but every embodiment may not necessarily include the particular feature, structure, or characteristic. Moreover, such phrases do not necessarily refer to the same embodiment. Further, when a particular feature, structure or characteristic is described in connection with an embodiment, it would be within the knowledge of one skilled in the art to effect such feature, structure or characteristic in connection with other embodiments whether or not explicitly described.
Fluid lenses have important advantages over conventional means of vision correction, such as rigid lenses and contact lenses. First, fluid lenses are easily adjustable. Thus, a presbyope who requires an additional positive power correction to view near objects can be fitted with a fluid lens of base power matching the distance prescription. The user can then adjust the fluid lens to obtain additional positive power correction as needed to view objects at intermediate and other distances.
Second, fluid lenses can be adjusted continuously over a desired power range by the wearer. As a result, the wearer can adjust the power to precisely match the refractive error for a particular object distance in a particular light environment. Thus, fluid lenses allow adjustment of power to compensate for alteration of the natural depth of focus of the eye that depends on the wearer's pupil size, which is in turn dependent on the ambient light level.
Third, although 20/20 vision, which corresponds to an image resolution of 1 minute of arc ( 1/60 degree) is generally acknowledged to represent an acceptable quality of vision, the human retina is capable of finer image resolution. It is known that a healthy human retina is capable of resolving 20 seconds of arc ( 1/300 degree). Corrective eyeglasses designed to enable a patient to achieve this superior level of vision have a resolution of about 0.10 D or better. This resolution can be achieved with continuously adjustable fluid lens elements.
In an embodiment of a fluid lens assembly, one or more fluid lenses may be provided with its own actuation system, so that a lens for each eye can be adjusted independently. This feature allows wearers, such as anisometropic patients, to correct any refractive error in each eye separately, so as to achieve appropriate correction in both eyes, which can result in better binocular vision and binocular summation.
In an embodiment, wheel 130 has a knurled edge in order to provide secure contact with the finger of the user as well more precise control over the translation of wheel 130.
Lens module 200 is connected via outlet port 245 to a connecting tube (not shown), which is connected to reservoir 150. Lens module 200 may further include a flexible back surface provided by, for example, a flexible membrane (not shown) stretched flat over the edge of a rigid optical lens. To change the optical power of fluid filled lens module 200, the membrane may be inflated through the addition of a fluid from reservoir 150.
The connecting tube delivers fluid from lens module 200 to reservoir 150 and vice versa. The connecting tube is designed to be relatively impermeable to the fluid contained therein. In an embodiment, the connecting tube is configured to allow a minimum flow rate at all times in order to ensure a minimum speed of response to the user moving wheel 130 in order to change the optical power of fluid filled lens module 200. The connecting tube is connected at one end to outlet port 245 of lens module 200 and at the other end to reservoir 150. In an embodiment, the overall assembly including the lens module 200, the connecting tube, and reservoir 150 is designed to maintain a seal excluding fluids and air for an overall use period of two years or more. In an embodiment, the connecting tube is thin in order to be accommodated within a hinge cavity. In an embodiment, it is less than 2.0 mm in outer diameter and less than 0.50 mm in wall thickness, in order to maintain an adequate flow of fluid. In an embodiment, it is capable of being bent by an angle of no less than 60 degrees. In an embodiment, it is capable of being bent by an angle of no less than 45 degrees without crimping. In an embodiment, it is durable to repeated flexing of the hinge.
Hinge block 250 and spring 230 are enclosed within a covered area between inner block 210 and outer block 240. Additional embodiments of the hinge and spring are described in U.S. application Ser. No. 12/904,769. Caliper actuator assembly 100 includes wheel 130 held in place by axle 280, slider 140, slider block 255, spacer block 290, and compression arm 270. These parts are assembled into a temple chassis subassembly (which is described further with respect to
In an embodiment, slider 140 maintains reservoir 150 in its compressed state as it moves away from distal end 160. As slider 140 is moved towards distal end 160, the compressing force on reservoir 150 is released, and reservoir 150 springs back to its original shape, temporarily creating low pressure on the fluid, and thus pulling fluid back from lens module 200.
The pieces of the various actuator assemblies described herein, for example, but not limited to, the temple cover, temple chassis, wheel, slider, spring, screws, inner block, outer block, axle, compression arm, spacer block, etc, may be manufactured through any suitable process, such as metal injection molding (MIM), cast, machining, plastic injection molding, and the like. The choice of materials may be further informed by the requirements of mechanical properties, temperature sensitivity, optical properties such as dispersion, moldability properties, or any other factor apparent to a person having ordinary skill in the art.
The fluid used in the fluid lens may be a colorless fluid, however, other embodiments include fluid that is tinted, depending on the application, such as if the intended application is for sunglasses. One example of fluid that may be used is manufactured by Dow Coming of Midland, Mich., under the name “diffusion pump oil,” which is also generally referred to as “silicone oil.”
The fluid lens may include a rigid optical lens made of glass, plastic, or any other suitable material. Other suitable materials include, for example and without limitation, Diethylglycol bisallyl carbonate (DEG-BAC), poly(methyl methacrylate) (PMMA), and a proprietary polyurea complex, trade name TRIVEX (PPG).
The fluid lens may include a membrane made of a flexible, transparent, water impermeable material, such as, for example and without limitation, clear and elastic polyolefins, polycycloaliphatics, polyethers, polyesters, polyimides and polyurethanes, for example, polyvinylidene chloride films, including commercially available films, such as those manufactured as MYLAR or SARAN. Other polymers suitable for use as membrane materials include, for example and without limitation, polysulfones, polyurethanes, polythiourethanes, polyethylene terephthalate, polymers of cycloolefins and aliphatic or alicyclic polyethers.
The connecting tube may be made of one or more materials such as TYGON (polyvinyl chloride), PVDF (Polyvinyledene fluoride), and natural rubber. For example, PVDF may be suitable based on its durability, permeability, and resistance to crimping.
The temple cover may be any suitable shape, and may be made of plastic, metal, or any other suitable material. In an embodiment, the temple cover is made of a lightweight material such as, for example and without limitation, high impact resistant plastics material, aluminum, titanium, or the like. In an embodiment, the temple cover may be made entirely or partly of a transparent material.
The reservoir may be made of, for example and without limitation, Polyvinyledene Difluoride, such as Heat-shrink VITON®, supplied by DuPont Performance Elastomers LLC of Wilmington, Del., DERRY-KYF 190 manufactured by DSG-CANUSA of Meckenheim, Germany (flexible), RW-175 manufactured by Tyco Electronics Corp. of Berwyn, Pa. (formerly Raychem Corp.) (semirigid), or any other suitable material. Additional embodiments of the reservoir are described in U.S. application Ser. No. No. 12/904,736.
a and 17b illustrate two embodiments of caliper actuator assemblies wherein the position of slider block 255 is changed in order to shorten the length of the lever arm.
Additional embodiments of actuators will now be described. Similarly to the caliper actuator embodiments described above, each of the following actuator embodiments serve to compress a reservoir located in one or more temples of a fluid-filled lens assembly in order to adjust the optical power of a fluid-filled lens.
a illustrates a side view of an embodiment of roll and translate actuator 1900 with vertical compression of reservoir 1930. Roll and translate actuator 1900 includes wheel 1910, slider 1920, reservoir 1930, and temple chassis 1940. In roll and translate actuator 1900, wheel 1910 translates along track 1960. Slider 1920 slides with wheel 1910 and compresses reservoir 1930 against temple chassis ceiling 1950 of temple chassis 1940.
a illustrates a side view of an embodiment of roll and translate actuator 2000 with horizontal compression of reservoir 2030. Roll and translate actuator 2000 includes wheel 2010, slider 2020, reservoir 2030, and temple chassis 2040. In roll and translate actuator 2000, wheel 2010 translates along temple chassis 2040. Slider 2020 slides with wheel 2010 and compresses reservoir 2030 against a vertical inner side surface 2050 of temple chassis 2040. In an embodiment, slider 2020 includes a wedge 2060 to facilitate the horizontal compression of reservoir 2030.
a is a side perspective view of reservoir 2030 of
a illustrates a front view of an embodiment of a rack and pinion actuator assembly 2200, according to an embodiment of the present invention. Rack and pinion actuator assembly 2200 includes slider bar 2270, rack portion 2210 of slider bar 2270, pinion 2220, wheel 2230, temple cover 2240, and reservoir 2260. Wheel 2230 and pinion 2220 are coupled together so that when wheel 2230 is rotated, pinion 2220 is also rotated. Teeth 2225 of pinion 2220 engage with teeth 2215 of rack portion 2210 of slider bar 2270. As a result, when wheel 2230 is rotated, slider bar 2270 moves to compress reservoir 2260 against temple chassis ceiling 2255 of temple chassis 2250.
a-c and 24 illustrate an embodiment of rack and pinion actuator assembly 2300 with horizontal compression of reservoir 2360.
a illustrates a side view of screw actuator assembly 2700 with vertical compression of reservoir 2740. Slider bar 2710 works in a similar way to the slider bars of previous embodiments. However, instead of a rack and pinion or other arrangement, screw actuator assembly 2700 provides for a worm gear arrangement between screw 2720 and slider bar 2710. When screw 2720 is rotated by rotation of dial 2730 by a user, slider bar 2710 moves to compress reservoir 2740 against temple chassis ceiling 2750 of temple chassis 2760.
a illustrates a side view of an embodiment of rotation actuator assembly 2800 with a pulley-type track 2810 with vertical compression of reservoir 2860. Slider bar 2820 works in a similar way to the slider bars of previous embodiments, except it is adhered to track 2810. When wheel 2830 is rotated, it moves track 2810 around pulleys 2840 and 2850. When track 2810 moves around pulleys 2840 and 2850, slider bar 2820 moves to compress reservoir 2860 against temple chassis ceiling 2880 of temple chassis 2870. In an embodiment, as shown in
a illustrates a side view of an embodiment of slide and translate actuator 2900 with horizontal compression of its reservoir (not shown). When slider button 2910 is translated along temple arm 2920, the slider bar (not shown) moves to compress the reservoir against the temple chassis.
Although various embodiments of the present invention have been described above, it should be understood that they have been presented by way of example only, and not limitation. It will be apparent to persons skilled in the relevant art that various changes in form and detail can be made therein without departing from the spirit and scope of the invention. Thus, the breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims and their equivalents.
Further, the purpose of the foregoing Abstract is to enable the U.S. Patent and Trademark Office and the public generally, and especially the scientists, engineers and practitioners in the art who are not familiar with patent or legal terms or phraseology, to determine quickly from a cursory inspection the nature and essence of the technical disclosure of the application. The Abstract is not intended to be limiting as to the scope of the present invention in any way.
Number | Date | Country | Kind |
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12904720 | Oct 2010 | US | national |
This application claims priority to U.S. Provisional Patent Application No. 61/251,819, filed Oct. 15, 2009, which is incorporated herein by reference in its entirety.
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/US10/52902 | 10/15/2010 | WO | 00 | 6/18/2012 |
Number | Date | Country | |
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61251819 | Oct 2009 | US |