Updated on February 5, 2024


Created on June 17, 2014


Upcoming Update

Eyejusters are self-adjustable eyeglasses, designed to set the focal length of the lens based on the usage.

Developed By
  1. EyeJusters
Content Partners


Product Description

Eyejusters are self-adjustable eyeglasses which eliminate the need to have different pairs of glasses for different tasks or for individuals who are unable to see an optometrist have glasses fit (developing countries). The design deal with presbyopia, a condition in old ages where the eyes lose the power to switch from near vision to far vision. The design allows the spectacles to move from convex to concave with the application of the fluid-filled lens.

Target SDGs

SDG 3: Good Health and Well-Being

Market Suggested Retail Price


Target Users (Target Impact Group)


Distributors / Implementing Organizations

Eyejusters Ltd design and manufacture the glasses. Eyejusters Ltd also sells glasses to distributors in developed countries and a portion of these sales covers donations of glasses that will be sent to distributors in developing countries. NGOs that have done distributions include: Peace Corps, Developing World Connections, Vision Action, Eyes for the World, and Mobile Health International.

Competitive Landscape

Direct competitors include Adspecs.

Manufacturing/Building Method

Eyejusters Ltd designs, manufacture, and sells the glasses. Organizations can purchase distribution kits from Eyejusters Ltd and deploy the glasses in the communities they work in.

Intellectural Property Type


User Provision Model

Online orders are available for shipment to the US, Canada, UK, and Europe. Individuals in developing countries can get Eyejusters through organizations in their communities working as local distributors.

Distributions to Date Status


Lens technology (type)

Slidelens ™

Near vision power range

+4.5 -> 0 D

Distance vision power range

0 -> -5 D

Glasses weight (g)


Frame dimensions (mm)

50 x 22 x 139 mm

UV protection (ray type blocked)

All UVB and most UVA rays are blocked

Frame features to adjust to face

Spring Hinges, Nose Pads

Minimum age of user (years)

14 years

Readjustable (yes/no)


Frame material


Design Specifications

Eyejusters are metal frame glasses with SlideLens™ technology. Each SlideLens is a pair of lenses with a special shape. When these lenses are slid across each other (left-to-right), their combined shapes act as if they were one lens with a changing spherical surface. The SlideLens technology allows Eyejusters users to self-adjust their glasses to their own vision needs. The glasses are adjusted with a removable dial on the side of the frame. The adjustable eyewear comes in two types: negative power to correct poor distance vision and positive power to correct near and farsightedness. Each Eyejuster box includes a pair of eyejusters, re-attachable adjuster dials, hard plastic case, cleaning cloth, instructions, and close vision chart.

Product Schematics

Technical Support

Eyejusters has comprehensive technical and support documents available on its website for distributors. Eyejusters also offers direct technical support via phone or email.

Replacement Components

The removable magnetic slider component used for making adjustments might need to be replaced if lost. Eyejusters supplies extra parts in their distribution kits.  



Manufacturer Specified Performance Parameters

  • Lens technology:  SlideLens™
  • Near vision Eyejusters power range: +4.5 ? 0 D
  • Distance vision Eyejusters power range: 0 ? -5.0 D
  • Glasses weight: 35g
  • UV protection (all UVB and most UVA rays are blocked)
  • Frame features to adjust to any face: Sprung Hinges, Nose Pads
  • Readjustable
  • Metal frame, multilayer, stainless, steel, or acetate frames

Vetted Performance Status

No testing has been completed.


As a class 1 medical device (deemed to be low risk) Eyejusters pose little to no risk to their user. Eyejusters Ltd does state that their product is intended for users age 14+ to ensure proper fit.  

Complementary Technical Systems


Academic Research and References

Sankaridurg, P., Donovan, L., Varnas, S., Ho, A., Chen, X., Martinez, A., … & Holden, B. (2010). Spectacle lenses designed to reduce progression of myopia: 12-month results. Optometry and vision science: official publication of the American Academy of Optometry87(9), 631.

Douali, M. G., & Silver, J. D. (2004). Self?optimised vision correction with adaptive spectacle lenses in developing countries. Ophthalmic and Physiological Optics24(3), 234-241.

Silver, J. D., Douali, M. G., Carlson, A. S., & Jenkin, L. (2010). How to use an adaptive optical approach to correct vision globally. South African Optometrist62(3), 126-131.

Additionally, the articles listed below are the result of a World Bank-funded clinical study, which found self-adjustable glasses to be reliable and effective; validating their use for children aged 12 and over.

He, M., Congdon, N., MacKenzie, G., Zeng, Y., Silver, J. D., & Ellwein, L. (2011). The child self-refraction study: results from urban Chinese children in Guangzhou. Ophthalmology118(6), 1162-1169.

Zhang, M., Zhang, R., He, M., Liang, W., Li, X., She, L., … & Moore, B. (2011). Self correction of refractive error among young people in rural China: results of cross sectional investigation. Bmj343, d4767.



Slidelens. “SlidelensTM Technology.” Eyejusters, 2020.


Sidelens. “SlidelensTM Developing World.” Eyejusters. Accessed January 31, 2020.

Compliance with regulations


Evaluation methods

Evaluation methods include analysis of quantitative data collected by international distributors.

Other Information


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