设计了一套液晶自适应光学扫描激光检眼镜,采用790nm近红外光进行波前探测、视网膜成像以增加受试者的舒适度:采用离轴反射式结构以避免透镜表面的杂散光对探测和成像的不利影响:采用开环校正模式以提高系统稳定性和能量利用率(比闭环高约1倍)。利用ZEMAX软件对成像系统进行模拟分析。证明系统自身可以达到接近衍射极限水平,MTF@33cycles/mm=0.38(对应视网膜上4μm),MTF@44cycles/mm=0.2(对应视网膜上3脚),轴向分辨率约80μm,满足设计要求。
A scanning laser ophthalmoscope (SLO) system with liquid crystal (LC) adaptive optics (AO) was designed. It adopted 790 nm near-infrared for wavefront detection and retinal imaging to increase the comfort for subjects; adopted off-axis parabolic mirror (OPM) to avoid the impact of unwanted ghost reflections for wavefront detection and retinal imaging; adopted the open loop mode correction to enhance the stability and light efficiency. The optical system was analyzed with ZEMAX, and proved to be almost diffraction-limited, MTF@33 cycles/ram=0.38 (corresponding to be retina 4 p,m), MTF@44 cycles/mm=0.2 (corresponding to be retina 3 μm), and the axial resolution is about 80 μm. So the system satisfies design requirements.