Smart contact lenses

Also known as Smart contact lens, Electronic contact lenses, AR contact lenses, Glucose-sensing contact lens

Smart contact lenses are soft lenses with sensors or micro-displays built in. One sensing lens, Sensimed's Triggerfish, has US marketing authorisation to help clinicians time eye pressure checks in glaucoma, but tear glucose sensing and display lenses have only been tested in small early studies and in animals.

Pilot and early commercialDemonstratedReviewed 21 Oct 2026
AI illustration · Illustrative scene, not a photograph of the specific device or experiment.

In plain language

A smart contact lens is a soft lens with tiny electronics added, such as a sensor that reacts to something in the tears or a very small screen. Most designs are still research prototypes. The lens has to stay comfortable, let light through, and avoid irritating the surface of the eye, which makes it much harder to build than a wrist-worn gadget.

The only sensing lens with regulatory authorisation so far is Triggerfish. It detects small changes in eye volume over a day, and the pattern can help show when eye pressure tends to be highest. It does not give a pressure reading in millimetres of mercury. Glucose-tracking lenses have been tested in rabbits and in small human pilots, and a display lens has been worn by one person in a short test. None has yet been shown to work reliably in everyday life.

Technical explanation

Smart contact lens designs fall into two broad groups: sensing lenses that read a chemical or physical signal, and display lenses that show an image to the wearer. A sensing lens combines a sensor with electronics such as an antenna and a chip. Elsherif and colleagues note that opaque materials, antennas and chips may block vision and reduce oxygen permeability (Elsherif and colleagues, 2022). Mojo Vision's display prototype used a micro-LED display (Optometry Times, 2022).

Triggerfish has the most clinical testing of the devices covered here. Its output is in arbitrary units, not mmHg (Mansouri and colleagues, 2012). In a 2012 trial of 40 glaucoma patients and suspects, two 24-hour sessions one week apart produced an overall between-session correlation of r = 0.59 across 36 patients with complete data. Correlation for daytime periods alone was lower, at r = 0.40 (Mansouri and colleagues, 2012). That agreement is fair rather than strong, which is one reason its clinical role remains narrow.

Tear glucose lenses face a different problem. Glucose in tears lags behind blood glucose, and the lag varies from person to person (Park and colleagues, 2024). A 2024 pilot in Nature Communications used a 10-minute settling period after the lens was inserted, so that tear glucose and tear volume could settle, and then applied a personal lag time to each participant's data. It reported high correlations with blood glucose for representative healthy and diabetic participants, but the study covered only 20 people over five test days. Verily, Alphabet's life sciences unit, reported in 2018 that consistently accurate glucose measurements from tears had proved difficult to obtain (Engadget, 2018).

What the evidence says

Each statement is typed by the strength of its evidence and linked to the source that supports it.

Demonstrated Shown in a published experiment, test or shipping product.

The US FDA permitted marketing of the Triggerfish sensing lens in 2016 for adults aged 22 and over, to help clinicians find the time of day when eye pressure may be highest so they can time measurements.

Sources: [2]

Triggerfish does not measure intraocular pressure directly. It detects small changes in eye volume, and its output is in arbitrary units, not absolute pressure in mmHg.

Sources: [2], [1]

In a 2012 prospective trial of 40 glaucoma patients and suspects, two 24-hour Triggerfish sessions produced 151 adverse events. Most were mild; the most common were blurred vision, redness of the conjunctiva and superficial punctate keratitis. No serious adverse events were recorded.

Sources: [1] · Results, safety and tolerability

Triggerfish readings from two 24-hour sessions a week apart had a correlation of r = 0.59 across 36 patients with complete data, and r = 0.40 for daytime periods only.

Sources: [1] · Results, reproducibility · medium confidence

Verily shelved its glucose-sensing contact lens, developed with Alcon since 2014, on 16 November 2018, after finding that consistently accurate glucose measurements from tears were difficult to obtain.

Sources: [4]

Mojo Vision stopped work on its smart contact lens in January 2023, citing difficulty raising capital, laid off around 75% of its staff and moved to its microLED display technology.

Sources: [6]

A 2022 review of wearable glucose-sensing lenses describes the in vivo work it covers as mainly rabbit studies and gives no human wearer results.

Sources: [7] · In vivo testing · medium confidence

Reported, unverified Stated by a company or team but not independently confirmed.

In a 2024 Nature Communications pilot, a wireless tear glucose lens reached a Pearson correlation of 0.97 with blood glucose for a representative healthy participant and 0.95 for a representative diabetic participant, after a personal time lag was applied. The study covered 10 healthy and 10 diabetic people over five test days.

Sources: [3] · Human study · medium confidence

In July 2022 Mojo Vision's CEO became the first, and at the time only, person to wear the latest prototype of its Mojo Lens, wearing one lens at a time for one hour. This is based on company statements.

Sources: [5] · medium confidence

Limitations and open problems

  • Triggerfish output is in arbitrary units rather than mmHg. The 2012 paper treats the link between lens output and eye pressure as an assumption, and notes that changes in corneal shape and thickness may affect the output (Mansouri and colleagues, 2012).
  • Human studies so far are small and short: 40 people in the main Triggerfish safety trial and 20 people in the 2024 tear glucose pilot over five test days.
  • Tear glucose readings are affected by biomolecules in tears (Engadget, 2018, quoting Verily) and need a settling period after insertion (Park and colleagues, 2024).
  • Practical problems include possible heating of the eye from electric current, eye irritation from hydrogen peroxide, short-lived enzyme sensors, and opaque electronics that can block vision and reduce oxygen permeability (Elsherif and colleagues, 2022).
  • The sources reviewed here report no multi-person human trial of a display lens, and Mojo Vision stopped work on its smart contact lens in January 2023 (UploadVR, 2023).
  • Some clinical work has had input from the sponsor. The 2012 Triggerfish trial notes sponsor involvement in its design and author ties to the company (Mansouri and colleagues, 2012).

Possible future uses

Speculative

Ideas, not predictions. None of these has been demonstrated.

  • Continuous, needle-free glucose tracking through tears, if day-to-day reliability and personal calibration can be made robust across many people.
  • Display lenses that give hands-free prompts or visual aids for people with low vision.
  • Lenses that combine sensing with drug release, so that a sensed value triggers treatment in the eye.

Product concepts: Eye pressure monitoring contact lens

Timeline

  1. Dec 2012A prospective trial reports 24-hour Triggerfish recordings in 40 glaucoma patients and suspects, with mostly mild adverse events and no serious ones. Sources: [1]
  2. 7 Mar 2016The US FDA permits marketing of Triggerfish through a De Novo pathway, for adults aged 22 and over, to help time intraocular pressure measurements. Sources: [2]
  3. 16 Nov 2018Verily shelves its glucose-sensing contact lens, developed with Alcon since 2014, after tear glucose readings prove too inconsistent. Sources: [4]
  4. 6 Jul 2022Mojo Vision's CEO becomes the first, and at the time only, person to wear the latest prototype of its Mojo Lens, one lens at a time for one hour. Sources: [5]
  5. 11 Jan 2023Mojo Vision stops work on its smart contact lens, cuts about 75% of its staff and shifts to microLED display technology. Sources: [6]
  6. 2 Apr 2024Nature Communications publishes a pilot of a wireless tear glucose lens in 10 healthy and 10 diabetic people. Sources: [3]

Futures this could help bring about

AI illustration
How far away?

Checking blood sugar without needles

Engineering prototypes · 2 of 5 steps done

Glossary

Intraocular pressure
The pressure of fluid inside the eye. It is monitored in people with glaucoma.
Pearson correlation (r)
A number from -1 to 1 showing how closely two sets of measurements move together. Values near 1 mean a close match.
MicroLED
A display built from very small light-emitting diodes. Mojo Vision used one in its lens prototype.

Sources

  1. peer reviewed paper
    Continuous 24-hour Intraocular Pressure Monitoring With a Contact Lens Sensor: Safety, Tolerability, and Reproducibility in Glaucoma Patients
    Mansouri K, Medeiros FA, Tafreshi A et al.. Archives of Ophthalmology, Dec 2012. DOI: 10.1001/archophthalmol.2012.2280. Accessed 21 Oct 2026.
  2. news
    FDA permits marketing of Sensimed's Triggerfish
    startupticker.ch, 7 Mar 2016. Accessed 21 Oct 2026.
  3. peer reviewed paper
    In-depth correlation analysis between tear glucose and blood glucose using a wireless smart contact lens
    Wonjung Park, Hunkyu Seo, Jeongho Kim. Nature Communications, 2 Apr 2024. DOI: 10.1038/s41467-024-47123-9. Accessed 21 Oct 2026.
  4. news
    Verily shelves its glucose-monitoring contact lens project
    Engadget, 16 Nov 2018. Accessed 21 Oct 2026.
  5. news
    In-eye testing begins for first AR-based, smart contact lens
    Optometry Times, 6 Jul 2022. Accessed 21 Oct 2026.
  6. news
    Mojo Vision Is Ceasing Work On Its Smart Contact Lens
    UploadVR, 11 Jan 2023. Accessed 21 Oct 2026.
  7. review article
    Wearable Smart Contact Lenses for Continual Glucose Monitoring: A Review
    Mohamed Elsherif, Rosalia Moreddu, Fahad Alam et al.. Frontiers in Medicine, 4 Apr 2022. DOI: 10.3389/fmed.2022.858784. Accessed 21 Oct 2026.

Revision history

3 changes since this profile was created.

Changes on 21 Oct 2026
Published on owner instruction (content loop iteration 7)fd22377
Sources and claims re-checked against originalsfbb434c
Initial profile drafted from primary sources7e66249