CAJ | 학술논문

为了实现活体人眼视网膜的高分辨率成像,设计了一套视网膜成像液晶自适应光学系统来校正人眼的动态变化像差.基于开环双波段模式,分别采用夏克-哈特曼波前传感器(SHWS)和基于硅基板上的液晶空间光调制器(LCOS-SLM)来探测和校正人眼以及系统的波前像差;且分别采用近红外波段(790 nm)的超发光二极管和可见光波段(570 nm)的激光器作为波前探测和校正成像光源.系统采用离轴反射式结构来提高光能利用率,减小色差.用ZEMAX对系统性能进行了分析,证明设计的系统能够达到衍射极限,MTF@30 lp/mm为0.4(对应视网膜上4 μm),MTF@50 lp/mm为0.16(对应视网膜上2.5 μm).和闭环折射式系统相比,能量利用率提高1倍以上,且杂光和色差干扰小,成像对比度好.
위료실현활체인안시망막적고분변솔성상,설계료일투시망막성상액정자괄응광학계통래교정인안적동태변화상차.기우개배쌍파단모식,분별채용하극-합특만파전전감기(SHWS)화기우규기판상적액정공간광조제기(LCOS-SLM)래탐측화교정인안이급계통적파전상차;차분별채용근홍외파단(790 nm)적초발광이겁관화가견광파단(570 nm)적격광기작위파전탐측화교정성상광원.계통채용리축반사식결구래제고광능이용솔,감소색차.용ZEMAX대계통성능진행료분석,증명설계적계통능구체도연사겁한,MTF@30 lp/mm위0.4(대응시망막상4 μm),MTF@50 lp/mm위0.16(대응시망막상2.5 μm).화폐배절사식계통상비,능량이용솔제고1배이상,차잡광화색차간우소,성상대비도호.
In order to obtain the high resolution human retinal images in vivo, an adaptive optical (AO) system for retinal imaging was designed to correct the dynamic human eye wavefront aberrations, especially high order ones. On the basis of an open-loop and two-wavelength mode, the system adopted a Shark-Hartmann wavefront sensor (SHWS) and a liquid crystal spatial light modulator to detect and correct the wavefront aberrations respectively and used a 790 nm near infrared luminescent diode and a 570 nm visible laser for the wavefront detection and retinal imaging. Furthermove,a reflective off-axis system was adopted to enhance the energy-utilizing rate and to avoid the chromatic aberrations and stray light.The optical system was simulated and analyzed with ZEMAX and results show that the optical system can achieve the diffractive limit, and MTF@30 lp/mm is 0.4(4 μm at retina),MTF@50 lp/mm is 0.16(2.5 μm at retina).Compared with the close-loop refractive AO system,the system has doubled the energy-utilizing rate at least,and shows its some merits in high energy-utilizing rate,low stray light and little disturbing effect caused by chromatic aberrations.