Portable wide-filed OCT/OCTA for retinal imaging

Optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA) have achieved great success in the field of ophthalmology and are essential in early screening and diagnosis. They could perform noninvasive structural and vascular imaging of the eye. However, most Chinese community hospitals do not have any OCT equipment, due to the high cost. Portable OCT equipment could provide mobile and shared medical diagnostic services as an ideal solution to above problem. Therefore, we design and demonstrate a portable SD-OCT/OCTA system for retinal imaging with A-scan rate of 120KHz, based on a broadband light source with center wavelength of 850nm and bandwidth of ~100nm. The proposed equipment, consists of a laptop and an OCT engine with 30×25×20cm3 size and ~5kg weight, could be carried by one person from a hospital to another. The portable system offers an axial resolution of ~3.8 μm, a transverse resolution of ~7 μm on retina and a wide field of view of ~60 degrees. The system parameters of scanning unit have been simulated and optimized using software to achieve focusing spot with diffraction limited size on retina. In a word, the proposed OCT/OCTA equipment offers a nice tradeoff between imaging performance and portability, therefore makes up for the shortcomings of traditional OCT and is hopeful to enable the sharing economy for OCT.