P08402: A hand-held instrument to measure visual refractive errors


Table of Contents

Over one billion people need glasses but do not own them. People who have correctable vision problems are often handicapped as a result as the lack of correction. Without glasses, simple tasks become more difficult or impossible, productivity slows, and accidents occur more frequently. Based purely on the lack of productivity and enjoyment, the lack of eyeglasses is one of the largest solvable problems in the developing world. In fact, it is significantly more common than often cited problems such as cataracts or glaucoma. Glasses could correct the majority of vision problems encountered in the developing world, reducing the impact of presbyopia, myopia, hyperopia, and astigmatism.

The Senior Design team will recreate an exsistng product called the FOCOMETER created by InFOCUS.InFOCUS (Interprofessional Fostering of Ophthalmic Care for Underserved Sectors) began in 1987 as an outreach project of the University of Houston College Optometry. The project produced the FOCOMETER an affordable refracting device appropriate to areas without access to professional personnel, electricity or costly equipment.

Administrative Information

Project Name
A hand-held instrument to measure visual refractive errors
Project Number
Project Family
Sustainable Technologies for Developing Countries
Sustainable Products, Systems and Technologies
Start Term
End Term
Faculty Guide
Dr. James Taylor of ISE
Faculty Consultant
Dr. Andres Carrano of ISE
Graduate Teaching Assistant
Primary Customer
Developing Countries
Customer contact information
customer company here
customer title here
customer email, phone, address, etc, here

Faculty Support

Faculty Support
Name Discipline Role E-mail Address
James Taylor ISE Guide jateie@rit.edu
Rob Stevens ME Guide rjseme@rit.edu
Andres Carrano ISE Consultant alceie@rit.edu
Brian Thorn ISE Consultant bkteie@rit.edu
Jamie Winebrake PP Consultant jjwgpt@rit.edu
Scott Hawker SE Consultant hawker@mail.rit.edu
Paul Grebinger ANTH Consultant pfggss@rit.edu
John Ward BUS/MKT Consultant jward@cob.rit.edu

Team Documents

Marketing Tool

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Important Concepts

What is Refractive Error
Refractive error means needing glasses to see. Uncorrected refractive error is easily fixed by an eye examination and the provision of appropriate glasses. However, in many developing countries there are little or no eyecare services in place, and glasses are either too expensive or simply not available.
What Causes Blindess
The five main causes of preventable global blindness are cataract; trachoma; onchocerciasis (river blindness); childhood blindness; and refractive errors and low vision
Is Vision Impairment a big deal?
There are 37 million blind people, including 1.4 million children (under the age of 15), and 124 million with severely impaired vision, resulting in a total of over 161 million visually impaired people. [WHO, November 2004]

These figures do not include people with uncorrected refractive error.

Visual impairment due to uncorrected refractive error (<6/18 in adults and <6/12 in children) has been estimated to affect as many as 200 to 250 million people. [B. Holden, ICEE estimates, 2005]

o Increased social isolation difficulties with daily living doubled, ease of social functioning reduced by half, religious participation reduced by half o Increased morbidity risk of falls doubled, risk of hip fractures increased 4 times, risk of depression increased 3 times o Increased mortality risk of death doubled. [Centre for Eye Research Australia 2001]

Vision impairment has a major impact on the country

Current Design

Website of Current Design
Name Webside Address Description
INFOCUS http://www.infocusonline.org/ InFOCUS (Interprofessional Fostering of Ophthalmic Care for Underserved Sectors) began in 1987 as an outreach project of the University of Houston College Optometry. The project produced the FOCOMETER an affordable refracting device appropriate to areas without access to professional personnel, electricity or costly equipment. This device became the centerpiece of a unique program designed to help medically underserved communities achieve self- reliance for basic vision care.




Based on Badal optics, the FOCOMETERallows the patient to view a real, unmagnified target, and bring it into focus, with a direct reading of spherical correction on a linear diopter scale.

Measurement of cylinder for astigmatism is easily accomplished, utilizing a "clock target" supplied with the instrument.

"Add" power requirements for presbyopes can also be measured, simply by first obtaining the distance correction and then adding plus power in small increments until a target at the desired "near" distance is clear.

In extensive field testing, the FOCOMETER was found to be as accurate as other methods of subjective refraction and retinoscopy. Field test data were published in Optometry and Vision Science (April 1993).

The subject looks through the FOCOMETERand adjusts the focus until the designated target is clear. The spectacle prescription can then be read directly on a linear diopter scale on the side of the instrument.

The design eliminates the need for many pieces which could be lost or broken and may be difficult to replace.

Many clinicians in the USA and other developed countries find the FOCOMETER useful for over-refraction of contact lens wearers and for patients ordinarily difficult to refract, such as patients with keratoconus.

Useful Websites
Name Webside Address Description
Environmental Protection Agency http://es.epa.gov/ncer/p3/index.html The P3: People, Prosperity and the Planet website can be used as a guide to view the current and past grants and projects done by other interdisciplinary groups interested in sustainability. P3 is a competition focused on benefiting people, promoting prosperity, and protecting the planet through innovative designs to address challenges to sustainability in both the developed and developing world.
United Nations Millennium Goals http://www.unmillenniumproject.org/goals/gti.htm#goal6 The Millennium Development Goals (MDGs) are the world's time-bound and quantified targets for addressing extreme poverty in its many dimensions-income poverty, hunger, disease, lack of adequate shelter, and exclusion-while promoting gender equality, education, and environmental sustainability. They are also basic human rights-the rights of each person on the planet to health, education, shelter, and security. This website can be used as guide to the current needs of the World
Low Cost Eyeglasses http://www.lowcosteyeglasses.net/index.html Low Cost Eyeglasses is the first winner in the Harvard Business School Social Enterprise Business Plan Contest. After extensive research and planning, Low Cost Eyeglasses won the contest in March, 2001. The team is currently working to make a low cost product available.


Mission Statement

Staffing Requirements

Intellectual Property Considerations

Preliminary Work Breakdown Structure

Team Values and Norms

Grading and Assessment Scheme

Required Resources

Concept Development

Identify Customer Needs

Establish Target Specifications

Generate Product Concepts

Select Product Concept(s)

Test Product Concept(s)

Set Final Specifications

System Level Design

Product Architecture

Detail Design

Design for Manufacturing and Assembly

Robust Design

Design for the Environment and Sustainability

Design for Reliability

Design for Safety

Testing and Refinement


Published Documents

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Concept Design Review Documents (SD I)

Detailed Design Review Documents (SD I)

Managerial Design Review Presentation (SD I)

Technical Conference Publication (SD II)

Poster Publication (SD II)

Managerial Design Review Presentation (SD II)

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