Images digitization and characterization of surface and fundus obtained through a slit lamp adapted

Abstract

Slit Lamp (SL) is the equipment commonly used in most eye clinics. This instrument allows to observe ocular structures of both the anterior segment and posterior segment with different magnification values. Currently is very common obtain images from SL with a Smartphone (for documentation purposes) by means of a simple adapter in the eyepiece. These images lose their diagnostic quality due to the information lose to correct the lack correction of optical aberrations and noise introduced by this system. This paper analyzes the hardware settings and image characterization to need diagnostic quality image in SL. For this purpose a universal adapter for SLR cameras were developed. To adquisition process image the camera software capture were use. They were captured 128 images: 73 of anterior segment, 25 fundus and the rest with a magnifying glass and panfunduscope. These images were characterized by type and noise power. For de full optical system the point spread function PSF and the consequent modulation transfer function MTF were determined. For the new image postprocessing the Lucy-Richardson deconvolution algorithm were applied. Finally in the SL the numerical aperture and F number (#f) were obtained. Those data, uncommon in the technical data of manufacturers, are of fundamental importance in future adaptations.