WO2012036638A1

WO2012036638A1 - Electroactive ophthalmic glasses and method of making the same.

Info

Publication number: WO2012036638A1
Application number: PCT/SG2011/000316
Authority: WO
Inventors: Nir Ellenbogen
Original assignee: Ceepro Pte. Ltd.
Priority date: 2010-09-16
Filing date: 2011-09-15
Publication date: 2012-03-22
Also published as: KR20130116872A; JP2013541730A; CN103221877A; SG179307A1

Abstract

A pair of ophthalmic glasses configured to retard myopia progression or substantially prevent myopia in a young person comprising a prescribed lens having a distance viewing lens portion, a near viewing lens portion, and a variable transparency element configured with a near viewing mode and a distance viewing mode. In the near viewing mode, the prescribed distance viewing lens portion is substantially opaque or non transparent and the near viewing lens portion is substantially clear or transparent. In the distance viewing mode both the distance viewing lens portion and the near viewing lens portion are substantially clear or transparent. The variable transparency element state (whether it is clear or opaque) is driven by electronics embedded in a frame. Embedded software determines near viewing mode versus distance viewing mode by analyzing distance readings to objects in front of the glasses which are provided by proximity detectors embedded in the frame.

Description

OPHTHALMIC GLASSES

Field

The present invention relates to ophthalmic glasses, particularly though not solely to glasses for the prevention of myopia or the retardation of myopia progression in general and particularly in young people.

Background

Myopia (Nearsightedness) is a condition where the eyeball is too long, or the cornea is too steep and the light coming into the eye is focused inside the eye rather than on the retina - at the back of the eye, as shown in Figure 1. As a result those with myopia see nearby objects clearly but distant objects appear blurred.

The prevalence of myopia in the Asia is significantly higher than in the western world. Myopia is the most common eye problem among children in the Asian progressive societies such as Singapore, Hong Kong, Taiwan and Japan. The condition is on the rise in China, as education systems become more demanding. The prevalence and severity of myopia have increased significantly over the past two decades worldwide. Statistics and medical evidence show that myopia progresses significantly from age 6 to 15.

In Asia, myopia progression in primary school children is the highest in the world. In 7-8 years old children Myopia progresses at the rate of more than 1 D (100 degrees) per year. Myopia affects 25% of seven year olds, 66% of 12 year olds, and 80% of 18 year olds. By the time these children reach adulthood, their myopia could be -8D or more. Children need stronger glasses as often as once a year and even once every 6 months. Myopia became a problem of public health concern in Asia. High level of myopia is not only an esthetical issue but it is a health issue as it increases significantly the risk of irreversible blindness at older ages. Various eye pathologies such as Macular Degeneration, Glaucoma, Retinal Detachment and retinal problems following cataract surgery are at much higher prevalence.

The common and traditional practice for correcting myopia in children is to prescribe them with a pair of eyeglasses with concave lenses that are shifting the image focus backwards towards the retina, resulting in clear vision. Eyeglasses are not preventing the development and the progression of myopia. They are just an optical correction to the eye optical dysfunction that allows children see clearly despite their optical dysfunction.

Why myopia develops and how could myopia progression be stopped? While scientifically, the causes of myopia development are not totally determined, studies show that myopia progression is caused by a combination of genetic and environmental factors. Myopia is much more common where one parent is myopic, and more common still with two myopic parents. However environmental factors are equally crucial. The key environmental factor is extensive reading and near work. Studies show that increased hours spent focusing close up, reading and sitting in front of a computer screen are strongly correlated with myopia progression.

Myopic children are usually prescribed with eyeglasses that correct their myopia - the distance vision deficiency. When we focus on near objects such as reading a book, the light enters the eye and focuses beyond the retina. In order to shift the light focus back to the retina, the lens in the eye must change shape to add focusing power to the eye. This process is called "accommodation". Studies show high correlation between extensive accommodation and myopia progression.

There are two main theories explaining the correlation between accommodation and myopia progression:

a. Excessive accommodation associated with near work places a load on the eye during development. This load could be reduced by increased growth of the eye, resulting in myopia. Some studies that measured the eyeball length have shown that the eyeball elongates during accommodation process

b. Insufficient accommodation when children are engaged in near-work activities ("Accommodative lag") is evident in many children (in some children more than in others). Accommodative lag results in hyperopic retinal defocus, excessive hyperopic defocus may trigger the visual regulation mechanism of ocular growth and elongate the eye Being aware of the strong correlation between accommodation and myopia progression, researchers conducted studies proposing various ways to minimize the amount of accommodation in children's daily life, and by this means to reduce myopia progression. One way for eliminating accommodation reducing myopia progression is using bi-focal glasses or progressive lenses as shown in Figure 2. The principle behind this idea is that reading is performed using the lower segment of the glasses. Upper segment provides the required refractive error correction for getting distant images focused on the retina while the lower segment is designed to focus on close objects. (+2D - +3D from distance correction). In this case no accommodation of the eye is required while reading or doing near activities. No accommodative lag is created and therefore no hyperopic defocus and no eye elongation is expected. Bi-focal or Multi focal lenses are effective in providing refractive correction for both distance and near vision for adults who suffer from decrease in accommodation range. In this case the person is enforced to use the lower segment for reading, because at the absence of accommodation capability, reading through the upper zone will result into a blurred image.

However as children have strong accommodation capabilities, there is no assurance that the child will really use the lower part of the lens for near activities. While using the standard Bi-focal or Multi-focal lenses, there is no mean to enforce the child to reframe from accommodation and move his look using the lower segment of the lens while reading.

There are several studies investigating the use of progressive lens. A multicenter, randomized, controlled trial in the United States, Correction of Myopia Progression Trial (COMET) in which progressive lenses were used, reports small but statistically significant effect of the progressive lenses in slowing myopia progression. An additional randomized controlled trial in Japan using progressive lenses in children shows a similar positive effect of progressive lenses in slowing myopic progression. However, the reported effect in those studies in retarding myopia progression is not practically substantial. Only about 25% reduction is shown. The main reason for the limited effect may be that children using progressive lenses tend not to switch and use the dedicated zones on their lenses for reading (the lower zones). Since their accommodation capability may be strong, children can read equally well by using the upper (distance) segment of the lens and performing accommodating. It is much more comfortable and intuitive to use the upper part in the lens all the time and apply accommodation when reading, rather then tilting the head and looking down. While at the beginning children may collaborate and try using the reading zone ih the lens, as time passes, they learn that using the upper part of the lens is not really necessary as it would not induce blur during near work, unlike in adults who are presbyopic, and thus, it is difficult to expect children to force themselves looking down, it is counter intuitive and inconvenient. Therefore they may stop using the reading zone, and simply use the upper - distance zone and continue accommodating.

While bi-focal or multi-focal glasses can reduce significantly accommodation needs and thus have the potential to slow down myopia progression, the way these glasses are practically used by children limits the efficacy and as a result has hardly any effect on myopia progression.

Other Bi-focal or Multi-focal clinical studies with myopic children have shown similar limited and inconsistent effect for this reason.

Summary

In general terms the invention proposes a pair of glasses prescribed to treat myopia (rather than correct it). The invention proposes glasses using a pair of bi-focal or multi- focal lenses, with a near addition of +2D to +3D which are configured with a mechanism that directs and encourages children to use the upper part of the lens for distance viewing, and the lower part of the lens for near viewing (rather than accommodating using the upper part of the lens). This may have the advantage that the treatment of myopia in children is more efficacious. In specific expressions of the invention there is provided a pair of glasses according to claim 1 and/or methods according to claims 31 , 32 and 34. In another specific expression of the invention, there is provided a method of forming a bevelled edge on a lens according to claim 35. Embodiments may be implemented according to any of claims 2 to 30, 33 and 36.

Brief Description of the Drawings

One or more example embodiments of the invention will now be described, with reference to the following figures, in which:

Figure 1 is a light ray diagram of a eye with myopia;

Figure 2 is a front view of prior art bifocal lenses;

Figure 3a is front view of the ophthalmic glasses according to the example embodiment in a distance viewing configuration;

Figure 3b is front view of the ophthalmic glasses according to the example embodiment in a near viewing configuration;

Figure 4 is a perspective view of a further example embodiment;

Figure 5a is a schematic diagram of the LC shutter in Figure 4;

Figure 5b is an exploded view of the LC shutter and the lenses in Figure 4;

Figure 6 is a schematic diagram of the proximity sensor in Figure 4;

Figure 7 in a wiring diagram of the glasses in Figure 4;

Figure 8 is a block diagram of the electronic components in Figure 4;

Figure 9 is a flow diagram of a method of manufacturing of the ophthalmic glasses according to the example embodiment

Figure 10a is a side view of a prior art lens and frame prior to installation;

Figure 10b is a side view of a prior art lens and frame prior after installation;

Figure 11 is a side view of the two part lens;

Figure 12 is a close up of the edge of the lenses; Figure 13 is a close up of the groove in the frame;

Figure 14 is a side view of the front lens being inserted;

Figure 15 is a side view of the back lens being inserted;

Figure 16 is a cross section of the frame showing a wiring conduit;

Figure 17 is a schematic diagram of the frame showing a nose pad assembly;

Figures 18 and 19 are photos of a prototype of the nose pad assembly in Figure 17; Figure 20 is a schematic diagram of a nose bridge insert;

Figure 21 is a photo of a video projection system;

Figure 22A is a schematic diagram of a symmetrical triangular edge of a regular lens; and

Figure 22B is a schematic diagram of a "split" lens attached to a blank to result in the symmetrical triangular edge of Figure 22A.

Detailed Description

Figure 3 shows a pair of ophthalmic glasses 300 using progressive or bi-focal lenses to treat or retard the progression of myopia in children according to the example embodiment. The lenses utilize a mechanism that forces the child to use the lower segment 302 of the lenses while reading. This will ensure that no prolonged accommodation (or minimum accommodation) is applied to view up-close objects and as such will expectedly reduce significantly or prevent completely myopia progression in children.

The glasses optical lens (bi-focal or progressive lens) incorporate a special Transparency Controlled Liquid Crystal film (TCLC) 304. The film 304 can change states from being completely transparent to a "milky", frosted, opaque state. The TCLC 304 transparency is controlled electronically. While the child is reading, the upper segment 306 of the lens turns automatically opaque. This forces the child to utilize only the lower segment of the lens, which has optical power prescribed for reading, avoiding the need to apply accommodation. When looking at distant objects the TCLC 304 becomes completely transparent and the eye naturally uses the distance refraction segment of the upper segment 306. The opaque portion may only be a portion of the upper segment 306 and may only be partially opaque or other partial encouragement to look through the lower segment 302. As shown in Figure 4 the electronics are embedded in the glasses frame. The electronics include a Micro Controller programmed with software 400, TCLC film voltage drivers, proximity sensors 402. The circuit power is provided by low profile multiple polymer lithium rechargeable batteries 404. The batteries 404 are charged by direct connectivity using a wall adapter with an industry standard micro USB connector 406. Alternatively, the batteries 404 may be charged by wireless energy transfer using inductive charging.

Smart activation

The glasses are activated automatically upon wearing the glasses. This is done via a touch or body sense sensor 408 located at the nose pad 410 of the glasses. There may be a sleep function for ultra low power consumption which activates if the glasses are not worn for an extended period. The touch or body sense sensor 408 may measure capacitance, which will change significantly depending on whether the contact touches human skin. It may include a single or multiple contact pads. Frame

The glasses frame may be Nylon based material such as Grilamid TR90LX material or similar. The nose pad 410 may be conductive soft polymer or silicon which is biocompatible for skin touch. Alternatively, the nose pad 410 may be any material which is biocompatible for skin touch. The temples edge 412 at the ear may be soft polymer or soft silicon long touch biocompatibility for skin touch and adjustability. The silicon at the nose bridge and temples / ear pieces may avoid the glasses slipping down the child's nose due to the extra weight of the glasses. The arms may be fixed and not foldable

TCLC

The TCLC 304 may be 0.1-0.3 mm thick and driven by a square wave 20-36 V. There are 2 active cells 502, 504 operated independently for each eye. Optionally, there may instead be 3 active cells per each eye thus dividing the lens into 3 different zones. In a further option, there may be a single TCLC cell which covers upper segment of lens 304. Each cell is a LC film is located between the 2 optical lenses 506, 508 with a conductive tab 510 having conductive lines for cell activation inserted into a slot in the frame as shown in Figures 5a and 5b. The tab is thus a Quick Assembly Mechanism (QAM) to enable "Field" Assembly (by Optician) of the LC shutter and electrical connectivity to the electrical board. Disassembly for lens exchange is easily performed by the Optician as well. The TCLC 304 may be flatly sandwiched between the optical lenses 506, 508.

The TCLC 304 may be opaque without power and clear when energised, or the other way round. The level of opaqueness may be chosen as only partially opaque as a safety feature. Micro controller

As shown in Figure 8 the Micro controller 400 and supporting circuitry is located on a main PCB board 800 with the proximity sensors 402 welded to the circuitry. The Battery 404 is connected to a small PCB 808. TCLC pads 510 are provided on the Main PCB 800 and Small PCB 808. Interconnection wiring 1600 from the left arm to the right arm and nose pad 410 is provided through the frame as shown in Figure 7.

The Micro controller 400 is low power, small foot print, low cost CPU with flash memory and wireless communication option. A voltage boost circuitry provides the output voltage to drive the LC 20-36V square wave (amplitude).

Management software

A remote computer may be wirelessly or through a micro USB port 406 connected to the CPU 400 and include management software. This may allow reporting of data such as "Wear time", "Reading time" and additional information for clinical evaluation. Parameters such as smart activation may be configurable.

Reading state detection

This detector 402 identifies when the child is reading or doing other near work, and turning automatically the upper lens (the distance zone) to be opaque. While looking at distance again, the detector 402 identifies the new position and clears the upper part of the lens.

As shown in Figure 6 the detector 402 may be an ultrasonic piezo sensor 600, transmitter and receiver driven by a square wave (amplitude), or may be an Infrared detector. There may be a transmitter on one side, and a receiver on the other side, although a central combined Tx/Rx transducer is also possible. The sensor 600 should be small, for example not larger than 9 mm in diameter and 5mm in length in a fully closed metal case.

An example sensor is a open case sensor 9 mm in diameter and 5mm in length produced by Murata™, Japan. This sensor operates at 5-10 V at frequency of 40Khz and has a resolution of 1cm

The detector 402 implements a decision algorithm that may reduce false state situations. The switch to reading state is not done instantly but with a slight delay. Thus brief glances may be filtered out and only stable reading situations (where prolonged accommodation is performed) activate the upper shutter. The purpose is to make it practical to the child, and eliminate "false activation". In addition it enables the child practice normal accommodation. Battery

The battery 404 may be a rechargeable polymer Lithium battery 3.7V ~80-110mAh Micro USB Connector

The battery may be charged via a charging module in the CPU. The charging module activates when an external AC- DC switching power supply, 5V is connected to the USB micro charger port 406. The port is IP55 water and dust protected. Alternatively a solar charger may be provided either externally or as part of the frame or inductive charging mechanism. Lens production

The front lens 506 may be a fixed prescription. It may be either bi-focal or multi focal with a near addition of +2.0D - +2.5D. The front lens 506 may be fixed without reference to the personal prescription of the user. The back lens 508 may be personalised to the prescription for the child to correct the individual child's myopia and astigmatism. The advantage may be cost. Bi-focal or multifocal lenses may be more expensive. By ordering large batches of the same lens cost may be reduced. Because the back lens 508 is a single focal lens, it may be cheaper to personalise to the prescription.

In the two part lens configuration shown in Figure 11 where each of the front lens 506 and/or back lens 508 is a "split" lens having a substantially flat side, the lens edges may not be machined using common lens production machinery. This is because using common lens production machinery, edge bevelling is performed upon regular lens having symmetrical triangular edges. Figure 22A shows a regular lens having a symmetrical triangular edge. Such a lens before edge bevelling also has an edge profile that is of regular standard dimensions.

A "split" lens - which may be a front lens 506 or a back lens 508 - has a substantially flat side and thus may not have a symmetrical edge profile. Also, each "split" lens may have edges which are not of standard dimensions (since they are "splits" of a regular lens).

The lack of edge symmetry and the lack of standard edge dimensions may be compensated by attaching a blank to a substantially flat side of each "split" lens. This is shown in Figure 22B where a "split" lens 2202 is attached to a blank 2204 using an adhesive 2206. The lens and blank combination is then machined as if it is a complete lens. The "split" lens may be attached to the blank in a removable manner using thin double-sided tape as the adhesive 2206. The blank used may be round or square. Frame production

As seen in Figure 9 the frames (except optical lens and LC film) are assembled at a production facility. The plastic parts are made using plastic injection moulding. Then the electronic circuitry, sensors and wiring are installed. All internal parts electronic board, battery and other parts are not replaceable.

The interconnection wiring 1600 between the left arm to the right arm and nose pad 410 in Figure 7, may be provided through the frame 1602 as shown in Figure 16. The frame 1602 generally provides a groove 1606 to seat the lens 1604. In order to hide the wiring 1600, an extension is made into the groove 1606 to form a wiring conduit 1608. The interconnection wiring 1600 is permanently installed in the wiring conduit 1608 during manufacturing by encapsulating it with resin or glue. Alternatively, it may be made into a flexible circuitry. Such a wiring conduit may also be installed in a standard frame to allow retrofitting.

Assembly method

The frame is manufactured as mention above and the lenses (according to a myopia treatment prescription) 506, 508 and LC film 304 are assembled by licensed central lab or qualified optician

Standard optical lens are held in glasses by various means. As shown in Figure 10 the most popular is by having a triangle groove in the glasses frame (standard dimensions of approx 2.2mm base 0.6 mm height). The lens shape is hedged by a hedging machine that cuts the lens to fit the frame shape and leaves a protrusion around the circumference of the lens fitting the plastic or glass lens to the frame precisely. The lens is inserted into the frame either by loosening the frame by heating (in case of plastic frames) or loosening the frame by opening small screws that tighten the 2 parts of frame together. Alternatively as shown in Figures 12 to 15 the front lens 506 is smaller than the back lens 508 and has a tapered edge 1300 that allows it to be inserted from the rear. Once installed the front lens 506 is temporarily held in place while the TCLC 304 is inserted. Then the angle of the groove 1302 in the frame allows the larger back lens 508 to slide into place from the back and lock all three components into place. This means that the split lenses can be easily installed by the optician and locked in place without any additional effort.

As shown in Figure 11 the lens according to the example embodiment is split into 2 lenses. The optical power is summation of 2 lenses. For example the front lens 506 is + 4 and the rear lens 508 is minus 2.5 thus net optical power is 1.5 dioptre. The TCLC film 304 is very thin (about 0.2 mm ) thus has no influence on the image quality.

Nose bridge construction

The QAM shown in Figure 8, may be replaced by an alternative nose bridge construction 1800 as shown in Figures 18 and 19. In this case the LC film 304 is still located between the 2 optical lenses 506, 508. However the conductive tab 510 is instead inserted into a slot 802 near to the nose pad 4 0. A single or double sided PCB 1804 located in the centre has conductive pads on its top surface to from contacts 1814. The PCB 1804 may be 0.5 mm thick. The conductive tabs 510 are positioned so that the contacts 1812 of the conductive tabs 5 0 touch the contacts 1814 of the PCB pads. A cover 1806 is then affixed over the conductive tabs 510 and PCB 1804 with a screw 1808 to secure them in place. In this manner the lenses and the liquid crystal film can be installed, electrically connected and locked in place by the optometrist in the shop without the need of a professional electronic technician.

The nose pad 410 shown in Figure 20 may be single unit or split unit and may include metal tabs 2000 which are inserted into the nose bridge construction 1800 and clamped in place by cover 1806. This allows the installation of different sized nose pads to suit individual wearers. The metal tabs 2000 may be flat or round and between 0.2-0.4mm thick to enable nose pad 410 insertion/replacement. The body sense contacts 408 may be encapsulated in nose pad 410 and connected to the metal tabs 2000. The metal tabs 2000 may then be electrically connected to the PCB 1804 via pressure touch using Zebra strips 1810 within the nose bridge cover 1806. Interconnection wiring 1600 may also be electrically connected to the PCB 1804 and/or nose pad 410. As mentioned above the wiring for the LC film 304 should be separated from the body sense sensor 408. For example the LC film 304 wiring may be along the top groove, and the body sense sensor 408 along the bottom grove. Video projection

The TCLC 304 may alternatively be achieved by projecting video on the upper segment 306 of the lens. The video projection may simply frost upper segment 306 of the lens. An example of such video projection is shown in Figure 21. The TCLC 304 may be replaced by a light-guide Optical Element (LOE) 2100. The LOE 2100 may be an ultra- thin lens design that embeds miniature, see-through elements in front of the eye. A mini projector 2102 may be embedded in the temple 2104 of the eyeglasses to project the frosting into the side of the LOE 2100. As the image travels to the centre 2106 of 6 the LOE 2100, it is reflected into the eye via see-through elements. In this case the image may simply be white noise in the top segment which will effectively block the upper segment 306 and force the use of the lower segment 302. In a further alternative the TCLC 304 may be a thin film coating adhered to the front or back surface of single bifocal lens.

While example embodiments of the invention have been described in detail, many variations are possible within the scope of the invention as claimed as will be clear to a skilled reader. For example, the child of this description may be a young person who is below 18 years old.

Reference Numerals 300 ophthalmic glasses

302 lower segment of lenses

304 Transparency Controlled Liquid Crystal film (TCLC)

306 upper segment of lenses 400 CPU programmed with software

402 proximity sensors

404 lithium rechargeable batteries

406 micro USB connector

408 touch or body sense sensor

410 nose pad

412 Temple edge 502/504 active cells

506/508 optical lenses

510 Transparency Controlled Liquid Crystal (TCLC) tab

600 sensor

800 main PCB board

808 small PCB

1600 interconnection wiring

1602 frame

1604 lens

1606 groove

1608 wiring conduit

1800 nose bridge construction

1802 slot near nose pad

1804 PCB

1806 cover

1808 screw

1810 conductive strip

1812/1814 contacts

2000 metal tabs

2100 Optical Element (LOE)

2102 projector 2104 temple 2106 centre of LOE

2202 "split" lens 2204 blank 2206 adhesive

Claims

Claims 1. A pair of ophthalmic glasses configured to retard myopia progression or substantially prevent myopia comprising:

a prescribed distance viewing lens portion,

a near viewing lens portion prescribed to retard myopia progression or substantially prevent myopia,

a variable transparency system configured with a mode for near viewing by a user with at least a portion of the prescribed distance viewing lens portion substantially, blocked, occluded, opaque or non transparent and at least a portion of the near viewing lens portion substantially clear or transparent, and configured with a mode for distance viewing by the user with at least a portion of the distance viewing lens portion substantially clear or transparent.

2. The glasses in claim 1 wherein the user is a young person below the age of 18.

3. The glasses in claim 1 or 2 wherein the variable transparency system comprises a variable transparency element sandwiched between an inner lens and an outer lens.

4. The glasses in claim 3 wherein the variable transparency element comprises one or more liquid crystal cells.

5. The glasses in claim 1 or 2 wherein the variable transparency system comprises a coating on at least a lens surface configured to change opacity depending on a signal from a controller.

6. The glasses in claim 1 or 2 wherein the variable transparency system comprises a video projector configured to substantially block, occlude, make opaque or make non transparent the prescribed distance viewing lens portion during the near viewing mode, and to substantially make clear or make transparent the prescribed distance viewing lens portion during the distance viewing mode

7. The glasses in claim 3 or 4 wherein the inner lens is a prescribed lens for the specific user and the outer lens is a fixed optical power lens.

8. The glasses in any one of claims 3, 4 and 7 wherein the inner lens is a negative dioptre lens and the outer lens is a positive dioptre lens.

9. The glasses in claim 8 wherein the outer lens has a bevelled edge substantially coterminous with an edge of the variable transparency element, and the inner lens has a bevelled edge substantially spaced from the edge of the variable transparency element.

10. The glasses in claim 9 further comprising a frame including a notch to accommodate the inner lens bevelled edge and the edge outer bevelled edge, the notch having a smaller circumference on an outer side compared to a larger circumference on an inner side, the larger circumference on the inner side configured to allow the outer lens, the variable transparency element and the inner lens to be installed from the inner side.

11. The glasses in any one of the preceding claims further comprising a frame including a soft nose pad and soft ear pieces.

12. The glasses in any one of the preceding claims further comprising a controller to determine whether the user is near viewing or distance viewing and to energise the variable transparency element to the near viewing mode or the distance viewing mode accordingly.

13. The glasses in claim 12 wherein the controller is configured to activate the distance viewing mode substantially immediately after determining the user is distance viewing, and to activate the near viewing mode after determining that the user is near viewing for more than a predetermined period of time.

14. The glasses in claim 12 or 13 wherein the controller comprises a distance detector to determine the distance between the glasses and the most significant object in front of the glasses.

15. The glasses in claim 14 wherein the distance detector comprises a transmitter and a receiver.

16. The glasses in claim 14 or 15 wherein the distance detector is an ultrasonic piezo electric transducer.

17. The glasses in claim 14 or 15 wherein the distance detector is an Infrared detector transducer.

18. The glasses in any one of the preceding claims wherein the portion of the distance viewing lens portion is only partially opaque in the near viewing state.

19. The glasses in any one of claim 12 to 17 further comprising a rechargeable battery to power the controller.

20. The glasses in claim 19 further comprising a water-sealed USB micro port configured to connect an external power supply to the rechargeable battery.

21. The glasses in claim 19 further comprising an inductive charger connected to the rechargeable battery, the inductive charger configured for wireless energy transfer from an external power supply to charge the rechargeable battery.

22. The glasses in any one of the preceding claims further comprising a

communication module configured to send glasses operation data and compliance data and/or receive updated settings or software from a remote unit.

23. The glasses in any one of the preceding claims configured to determine whether the user is wearing the glasses and enter a low power mode if the glasses are not worn.

24. The glasses in any one of the preceding claims configured to enter an ultra low power mode if the glasses are not worn for an extended period.

25. The glasses in claim 20 wherein the controller is located inside an arm and the battery is located inside another arm.

26. The glasses in any one of the preceding claims wherein the prescribed distance viewing lens portion and the near viewing portion are part of a Bifocal lens(es) or a progressive lens(es).

27. The glasses in any one of the preceding claims further comprising an intermediate viewing lens portion, wherein the variable transparency system is further configured with a mode for intermediate viewing by the user with at least a portion of the prescribed distance viewing lens portion substantially opaque or non transparent, at least a portion of the intermediate viewing lens portion, and the near viewing lens portion being substantially clear or transparent, and in the near viewing mode at least a portion of the intermediate viewing lens portion and the prescribed distance viewing lens portion being substantially opaque or non transparent, and at least a portion of the near viewing lens portion being substantially clear or transparent.

28. The glasses in claim 10 wherein the variable transparency system comprises electrical wiring and the notch further comprises a wiring conduit within a deeper groove configured to house the wiring.

29. The glasses in claim 28 wherein the frame further comprising a nose bridge configured to electrically connect and removably clamp a set of contacts for the variable transparency element to the wiring.

30. The glasses in claim 28 further comprising a removable nose pad having metal tabs configured to be removably clamped by the nose bridge.

31. A method of fabricating ophthalmic glasses configured to retard myopia progression or substantially prevent myopia comprising:

installing an outer lens in a frame,

installing a variable transparency element adjacent the outer lens,

installing an inner lens adjacent the variable transparency element, and electrically connecting the variable transparency element to a controller.

32. A method comprising:

measuring a degree of myopia and astigmatism in a user;

providing a distance viewing lens portion having an optical power based on the degree of myopia and astigmatism,

providing a near viewing lens portion having an optical power designed to retard myopia progression or substantially prevent myopia in the user based on the degree of myopia, and

providing a variable transparency element adjacent the distance viewing lens portion and/or the near viewing lens portion.

33. The method of claim 32 further comprising determining if the user has myopia.

34. A method comprising:

providing eyeglasses with a prescribed distance viewing lens portion and a near viewing lens portion,

viewing a distant object using the distance viewing lens portion, and

occluding the distance viewing lens portion when viewing a near object using the near viewing lens portion.

35. A method of fabricating a lens comprising:

attaching a lens portion to a blank,

bevelling an edge of the lens portion and the blank, and

removing the blank from the lens portion.

36. The method of claim 35 wherein the lens further comprises a further lens portion, the lens portion and the further lens portion being co-aligned to thereby form the lens.