A Novel Device to Exploit the Smartphone Camera for Fundus Photography

Area of Science:

• Ophthalmology
• Medical Devices
• Optical Engineering

Background:

• Direct ophthalmoscopy is crucial for retinal examination but can be limited by user skill and portability.
• Current methods for retinal imaging may not be accessible or convenient for widespread screening.

Purpose of the Study:

• To design and construct an inexpensive, portable smartphone attachment for acquiring still and live retinal images.
• To evaluate the feasibility of using smartphone-based technology for ophthalmoscopy.

Main Methods:

• A compact optical device, utilizing direct ophthalmoscopy principles, was engineered for magnetic attachment to smartphones.
• Cross-polarization techniques were integrated to minimize corneal reflections.
• Retinal images of normal and pathological fundi were captured using the prototype.

Main Results:

• The attachment achieved a field-of-view up to approximately 20° with clinically relevant resolution.
• Corneal Purkinje reflections were significantly reduced, allowing imaging through undilated pupils.
• The device operated within safe light emission limits.

Conclusions:

• This smartphone-based optical attachment offers an affordable and convenient alternative to traditional direct ophthalmoscopes.
• Its portability and smartphone integration facilitate retinal screening and telemedicine in diverse, non-hospital settings.
• The technology holds potential for democratizing ophthalmic diagnostics.