Contact lens for increasing tear production
Described here are devices, systems, and methods for increasing tear production by stimulating the cornea, conjunctiva, and/or subconjunctiva. In some variations, the devices may be in the form of a contact lens. The contact lens may comprise a lens body and a stimulator chip, where the stimulator chip is embedded in the lens body. An external power source wirelessly transmits energy to the stimulator chip, where the stimulator chip may convert the energy to an electric waveform to stimulate the cornea, conjunctiva, and/or subconjunctiva. Stimulation may activate the lacrimal reflex to increase tear production. The devices and systems for increasing tear production may be used in methods of treating dry eye, reducing the symptoms of tired eye, increasing comfort for contact lens wearers, and extending the number of years a contact lens user can wear contacts. Also described are methods of manufacturing a contact lens.
1. A system for increasing tear production in an eye of a subject, the system comprising:
a device configured for placement on a cornea, the device comprising:
a contact lens comprising a lens body;
a stimulator chip embedded in the lens body and configured to stimulate the cornea or a conjunctiva of the eye, wherein the stimulator chip comprises an integrated circuit; and
a counterweight embedded in the lens body, wherein the counterweight is non-stimulating and is configured to balance a mass of the stimulator chip, such that the contact lens is rotationally unstable; and
an external power source for transmitting energy wirelessly to the stimulator chip to activate the stimulator chip.
2. The system of claim 1 , wherein the contact lens is a corrective contact lens.
3. The system of claim 1 , wherein the contact lens is a non-corrective contact lens.
4. The system of claim 1 , wherein the external power source is configured to emit 10 mW, pulsed at a 1% duty cycle.
5. A method of increasing tear production in a subject, comprising:
transmitting energy wirelessly from an external power source to a stimulator chip, wherein the stimulator chip and a counterweight are embedded in a contact lens worn by the subject, wherein the counterweight is non-stimulating and is configured to balance a mass of the stimulator chip, such that the contact lens is rotationally unstable, and wherein the stimulator chip comprises a photodiode and an electrical contact in communication with the photodiode through a via; and
delivering a stimulus from the stimulator chip to a conjunctiva or a cornea of the eye to produce tears.
6. The method of claim 5 , wherein the external power source comprises a light source.
7. The method of claim 6 , wherein the light source comprises a laser diode.
8. The method of claim 6 , wherein the light source comprises an infrared light-emitting diode.
9. The method of claim 6 , further comprising moving the eye or an eyelid to expose the photodiode to the light source.
10. The method of claim 5 , wherein transmitting energy wirelessly from the external power source comprises emitting 10 mW, pulsed at 1% duty cycle, from the external power source.
11. A system for increasing tear production in an eye of a subject, the system comprising:
a device configured for placement on a cornea, wherein the device comprises:
a contact lens comprising a lens body;
a stimulator chip embedded in the lens body and configured to stimulate the cornea or a conjunctiva of the eye, wherein the stimulator chip comprises a photodiode and an electrical contact in communication with the photodiode through a via; and
a counterweight embedded in the lens body, wherein the counterweight is non-stimulating and is configured to balance a mass of the stimulator chip, such that the contact lens is rotationally unstable; and
an external power source for transmitting energy wirelessly to the stimulator chip to activate the stimulator chip.
12. The system of claim 11 , wherein the counterweight is located approximately 180 degrees from the stimulator chip.
13. The system of claim 11 , wherein the lens body has a posterior surface configured to contact the conjunctiva of the eye, and the stimulator chip is embedded in the lens body within 20 microns of the posterior surface.
14. The system of claim 11 , wherein the stimulator chip is embedded in a portion of the lens body that is configured to be in front of an iris of the eye when the device is placed on the cornea of the eye.
15. The system of claim 11 , wherein the external power source comprises a laser diode.
16. The system of claim 15 , wherein the laser diode produces light comprising wavelengths between approximately 880 nm and 930 nm.
17. The system of claim 11 , wherein the external power source comprises an infrared light-emitting diode.
18. The system of claim 11 , wherein the external power source comprises an optical modifier to produce non-collimated light.
19. The system of claim 11 , wherein the lens body is a corrective lens.
20. The system of claim 11 , wherein the lens body has a zero power.
21. The system of claim 11 , wherein the external power source is configured to emit 10 mW, pulsed at a 1% duty cycle.