Purchase this article with an account.
Kari V Vienola, Boy Braaf, Mathivanan Damodaran, Koenraad Arndt Vermeer, Johannes F de Boer; Parallel scanning laser ophthalmoscope (PSLO) for high-speed retinal imaging. Invest. Ophthalmol. Vis. Sci. 2014;55(13):1603.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
High-speed imaging of the retina is crucial for obtaining high quality images in the presence of eye motion. To improve the speed of traditional scanners, a high-speed ophthalmic device is presented using a digital micro-mirror device (DMD) for confocal imaging with multiple simultaneous spots.
The PSLO consists of three parts: an illumination, an imaging and a detector arm (Fig. 1). The DMD is uniformly illuminated with a near-infrared (850 nm) LED. The separation between ON positioned mirror elements was made large enough to eliminate cross-talk between neighboring virtual pinholes, and therefore allowed multi-spot confocal imaging across the whole field of view (FOV). The DMD is programmed to project series of shifted point pattern configurations, effectively scanning the spots over the sample surface. The DMD was imaged onto a sample and the returning light was tapped of via a beam-splitter and imaged on a CMOS camera. Multiple point illuminated frames are combined to form one confocal wide-field image. As a proof of principle images of a resolution target were acquired with the PSLO system.
The resolution target was imaged with a pattern with virtual pinhole size of 2x2 mirrors and the separation between two pinholes was 4 mirror elements. Figure 1B shows the results for combining 9 illumination patterns to form the final image.
It is possible to create wide-field confocal images with the PSLO system. In theory the DMD can achieve higher frame rates than traditional scanner-based systems by illuminating the sample with multiple spots. In retinal imaging, such a setup will provide better images because higher imaging speeds reduce motion artifacts.
This PDF is available to Subscribers Only