Instant Vision Assessment Device

A simple subjective telescopic refraction system has been custom designed and built. The telescopic refraction accommodates a range of refractive errors from +0.62D to -9.37D, which is skewed towards the various amounts of myopia due to the prevalence of myopia in Asia. This range can be modified in order to capture the specific distribution of refractive errors of a population.

In using the calibrated 2.4X telescope for subjective refraction, the length of the telescope and the position of the stenopaic slit are adjusted by the examiner while the subject focuses a target on a distant visual acuity chart. The slit’s size and position can be changed easily thus enabling the examiner to obtain the refractive error findings easily by changing the length of the telescope. Refractive error can be measured in a few minutes. Since it is subjectively determined, it is generally more reliable than those findings obtained with objective refraction techniques.

Special Features and Advantages
• Advanced design, small size and low cost
• Easy to use: only short period of training is needed
• Efficient, reliable and accurate assessment of refractive error

Applications
• The device can be used as a portable subjective refraction system determining the refractive errors of patients who cannot access the services of an optometrist or ophthalmologist
• The device can be used as a pair of full field binoculars without the stenopaic slits
• The device can be used as a low vision aid for the partially sighted

Award
Prize of Minister Fientje Moerman & Gold Award, Brussels Eureka 2004 – the 53rd World Exhibition of Innovation, Research and New Technology (November 2004)

Principal Investigator
Prof. George WOO
School of Optometry
The Hong Kong Polytechnic University

Contact Details
Institute for Entrepreneurship
The Hong Kong Polytechnic University
Tel: (852) 3400 2929
Fax: (852) 2333 2410
Email: [email protected]