Journal: Biomedical Optics Express
Article Title: Wide-field OCT angiography for non-human primate retinal imaging
doi: 10.1364/BOE.525839
Figure Lengend Snippet: 200-kHz wide-field swept source OCT system. (A) Diagram of the system design. The wavelength-tuning laser light is first coupled into the OCT system using an 80/20 fiber optic coupler. Twenty percent of the power is split into the reference arm and the sample arm. In the reference arm, a customized motorized optical delay line is used to change the length of the optical path. A set of customized lenses is used in the reference arm to acquire 60-degree field-of-view images. The reflected light from both the reference arm and the sample arm interferes in the 50/50 coupler. The interference signal is then collected by a balanced photodetector, and the signal is acquired by a digitizer and processed by a PC. (B) 3D modeling of the OCT system: The red line indicates the optical path of the sample arm, the green line indicates the optical path of the fixation target, the yellow line indicates the optical path of the pupil camera, and the purple line indicates the optical path of the reference arm. Because animals were anesthetized, the fixation target was used only for system development. C1 is the reference arm collimator, M1, M2, and M3 are protected silver-coated mirrors, C2 is the sample arm collimator, E1 is an electrically tunable lens, G is a galvanometer scanner, D1 and D2 are dichroic mirrors. (C) Optical simulation (OpticStudio, Zemax) of the sample arm telescope: L1 and L2 are two customized lens sets. The lenses were designed based on simulation with this software. The red line indicates the +30° scanning light, blue indicates the 0° scanning light, and green indicates the -30° scanning light. The corresponding spot diagrams indicate that this system can achieve diffraction-limited imaging throughout the imaging field. (D) The complete system setup from the operator’s perspective: both OCT reference and sample arms are in the OCT box. The laser and a PC are embedded under the table. (F) An non-human primate being imaged with the device.
Article Snippet: This lens set was optimized for the NHP eye based on a human eye model provided by the optical design software, OpticStudio (Zemax), used for simulations, modified to include an axial length of 18 mm, equivalent to 75% of the size of a human eye ( ).
Techniques: Software, Imaging
