Patent Application
20200218092
The present invention relates to corrective lens manufacturing, more particularly to a method of dynamic electronic storage of corrective lens manufacturing criteria on eyeglass frames and eyeglass frames formed thereby.
The use of corrective lenses containing multiple optical powers to treat presbyopia, the typically age-related loss of adaptive focusing ability in the human eye, has been in wide use since the late 18th century. Early approaches to the problem were later refined into the bifocal and trifocal lenses seen today.
In the 20th century multifocal lenses with a gradual transition to the addition power were commercialized. Known as Progressive Addition Lenses (PAL's) or progressive lenses, they offered the patient better optical properties than bifocal or trifocal lenses, given their ability to gradually transition to the add power; and improved cosmetics since they eliminated the visible line or circle at what is known as the power boundary.
As PAL's became popular, conventional lens fabrication techniques were adapted to fabricate the patient's prescription with these new features. In conventional ophthalmic lens surface generation for a patient that does not suffer from presbyopia, known as single vision manufacturing in the industry, a spherically symmetrical lens blank with known front surface radius is attached to a metal block with a low melting point material, in a process called blocking. Due to the spherical symmetry of the lens the blank location on the block is not restricted in rotation. After blocking, the back surface of the lens is machined to create the necessary curvatures in two perpendicular meridians (referred to as sphere and cylinder). Utilizing different radii in the two perpendicular meridians, the patient's vision can be corrected for astigmatism. There is no add power correction for presbyopia in this type of lens.
In conventional manufacturing of a progressive lens the back surface generation process is the same as that used for single vision but an add power is molded into a specific area of the front surface of the blank to correct the patient's presbyopia. Since the location of the add power portion relative to the patient's pupil is important, the blocking process for a front surface progressive is more complex because the blank must be located precisely relative to the patient's pupil. To facilitate this location process for lens fabricators, progressive lens blank manufacturers engraved circles in and affixed tape markings on the front surface of the blank.
In the early 21st century, progressive lens manufacturing changed with the advent of digital lens designs. With digital lens designing technology, the add power along with the patient's sphere and cylinder prescription is now conventionally machined into the back surface of a lens blank with a spherical front like that used for the single vision process.
Some advantages of this approach are: 1) single vision lens blanks can be used and they are simpler to block than front surface progressives; 2) add power profiles can be better customized for the patient; 3) the fabricator's inventory of blanks can be smaller and less expensive because there is no need to stock different add powers as is the case with front surface progressive lenses; and 4) front surface progressive blanks are more expensive than simple spherical front surface blanks. Further having select manufacturing criteria on the lens itself allows the patient to easily have replacement lenses formed as needed.
Since single vision blanks are used for digital lens manufacturing and they do not have location marks, standards have been developed to engrave semi-visible marks in the back surfaces of digital lenses that are analogous to those of front surface progressive lenses. Note that it is possible and indeed commonly done in practice to engrave visible marks in the periphery of digital lenses, outside of the usable area, so that fabricators can properly locate a lens in a frame without using the engraved circles and markings.
The practice of engraving semi-visible marks in the back surface of digital lenses can have several issues: 1) suitable engraving equipment is expensive from a capital expenditure standpoint, generally requiring precision positioning equipment and excimer lasers; 2) near sighted patients that have prescriptions with high negative powers sometimes report they are able to see the marks and thus find them distracting; 3) engraving can cause complications during the various coating processes typically used for ophthalmic lenses, resulting in rework or scrap. As a result of these difficulties limited information is provided.
There remains a need for an efficient effective method of storing corrective lens manufacturing criteria.
One aspect of the present invention provides a method of dynamic electronic storage of corrective lens manufacturing criteria which comprises the steps of: a) providing eyeglass frame for holding a pair of corrective lenses; b) coupling a rewritable electronic storage medium to the eyeglass frame ;c) storing corrective lens manufacturing criteria on the rewritable electronic storage medium. The corrective lens manufacturing criteria includes a distance power reference location, a near power reference location and a prism reference point location, astigmatism criteria, magnitudes and angles for prism, distance and near field vision correction of single vision or progressive lenses, lens design type and lens design vender. The rewritable electronic storage medium may be an RFID device embedded within a temple part of the frame, or a QR Code, including a micro QR code, which is linked to a webpage containing the corrective lens manufacturing criteria.
The present invention provides eyeglass frames formed by the process of the invention, wherein the eyeglass frame becomes integrated with the specific corrective lenses associated therewith.
These and other advantages of the present invention will be described in connection with the preferred embodiments that are disclosed in connection with attached figures wherein like reference numerals represent like elements throughout.
The eyeglass frame 10 has two basic parts, a frame front 14 and the two temples 12. The frame front 14 will have two areas or openings 16 for receiving the corrective lenses 20 therein coupled by a bridge 18. The eyeglass frame 10 may be made from a number of materials such as plastic, metal, wood and even bone, and combinations thereof. Plastic materials such as cellulose acetate, xylonite, cellulose propionate and nylon are quite common and yield a strong lightweight frame.
In the first embodiment of the present invention the innovation is using a rewritable electronic storage medium 30 formed as a passive RFID device or RFID tag. Passive RFID device means the device requires no internal power source such as a battery. The radio frequency identification (RFID) device is capable of non-volatile storage meaning the data is retained without power applied. As known in the art a passive tag is an RFID tag that does not contain a battery wherein the power is supplied by the reader. When radio waves from the reader are encountered by a passive RFID tag, the coiled antenna within the tag forms a magnetic field. The tag draws power from it, energizing the circuits in the tag. The tag then sends the information encoded in the tag's memory. The medium 30 is programmed to contain all the required information for manufacturing of the corrective lenses 20 associated with the frame.
The collection of information is referenced herein as the corrective lens manufacturing criteria, some of which will be discussed further below.
RFID tags used as medium 30 can store significantly more corrective lens manufacturing criteria than what data has been currently engraved on lenses 20, and it is anticipated that the power locations 26 and 28, astigmatism, magnitudes and angles for prism, distance and near field vision correction of single vision or progressive lenses, as well as other lens properties such as lens design type, lens design vender can also be included. Commercially available RFID tags of approximately 3 mm by 3 mm by 1 mm exhibit sufficient storage and is small enough to affix to an eyeglass frame 10 in an unobtrusive manner and effectively form the medium 30 of the invention. It is preferred that the embodiment will use an RFID device 30 that possesses the ability to read and write to its storage locations multiple times. This allows lenses 20 to be changed in an existing frame 10 multiple times, as an individual's lenses prescription can change over the life of a given frame 10.
Also important is the potential to use the RFID device's internal serial number as a link correlating the lens or lenses 20 and frame 10 to a database of information concerning their assignment to a patient, a doctor and/or a lab.
The RFID reading and programming device 32 is also in communication with the device 30 via antenna 36 for reading from and writing to the device. The protocols and details of the RFID reading and programming are well known in the art and will not be detailed in this discussion.
Some frames 10 may not accommodate QR code 50 of 0.4″. A micro QR code 60 is developed shown in
Currently progressive lens engravings contain limited information: add power, lens design vendor identity and reference circles separated by 34 mm whose midpoint is typically the optical center of the lens.
With the invention described herein several benefits ensue. For example more information can be encoded than is currently practical with engraving, with virtually unlimited data available in the second embodiment of the present invention. Capital expenditure for the optics lab can be greatly reduced since it is believed an RFID reader/programmer can be integrated into a lab's operations for much less money than a suitable lens engraving system, and similarly in the second embodiment QR scanners are almost no cost and the cost of setting up and maintaining webpages 80 for each frame 10 are believed to be far less than the existing capital engraving expense. It should further be understood that there are methods of monetizing the pages 80 for the vendor 90 under SAAS models. The chance of rework and scrap due to engraving issues is eliminated with the present invention. Cycle time for processing a lens will improve considerably since engraving operations typically take up to a minute and it is believed the RFID read/write process and QR scanning web page read/write process can be many times faster. Further, if a finished pair of eyeglasses are separated from their hardcopy manufacturing documentation before they are dispensed to the patient, the invention described herein provides the lab with an easy mechanism to associate their finished goods with the proper patient, namely the RFID device's internal serial number be used to correlate the lens or lenses 20 and frame 10 to a database of information concerning their assignment to a patient, doctor and/or lab, or the unique webpage 80 of the second embodiment may similarly be utilized.
Although the present invention has been described with particularity herein, the scope of the present invention is not limited to the specific embodiment disclosed. It will be apparent to those of ordinary skill in the art that various modifications may be made to the present invention without departing from the spirit and scope thereof. The scope of the invention is not to be limited by the illustrative examples described above.
The present application claims the benefit of U.S. Provisional Patent Application Ser. No. 62/790,226, filed Jan. 9, 2019 titled “Method of Dynamic Electronic Storage of Corrective Lens Manufacturing Criteria on Eyeglass Frames and Eyeglass Frames Formed Thereby” which application is incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| 62790226 | Jan 2019 | US |
