基于结构光照明的数字全息显微术  

Digital Holographic Microscopy by Using Structured Illumination

作　　者：袁操今[1] 冯少彤[1] 聂守平[1] 

机构地区：[1]南京师范大学物理科学与技术学院,江苏南京210023

出　　处：《中国激光》2016年第6期250-261,共12页Chinese Journal of Lasers

基　　金：国家自然科学基金(61377003);江苏省高校自然科学研究重大项目(14KJA140001);南京师范大学高层次人才科研启动基金(184080H20162);南京师范大学青年领军人才培养项目(184080H20178)

摘　　要：通过调制入射光的振幅和相位,形成特殊结构分布的照明光以提高数字全息显微记录系统分辨率,结合结构光的特性设计了明场和暗场记录系统。明场记录系统中,在利用振幅型正弦光栅和随机散射元件调制入射光波前,将超出衍射极限的物体高频信息调制到系统截止频率以内,这部分信息可以通过成像系统被记录。数字再现过程中,将其与低频信息合成,可使再现像分辨率得到提高。在暗场记录系统中,通过在空间光调制器上加载相息图改变入射光的振幅和相位分布,分别用拉盖尔-高斯涡旋、径向艾里以及携带涡旋相位的径向艾里结构光照明物体,结合暗场聚光镜的应用,提高系统的分辨率和对比度。Structured illumination formed by modulating the phase and the amplitude of input beams is used to improve the resolution of digital holographic microscopy. According to the properties of structured illumination, bright-field and dark-field recording systems are built. In the bright-field system, an amplitude type sinusoidal grating and scattering elements are used to modulate the high frequency information which overpasses the diffraction limit into the frequency lower than the cut-off frequency, which can be recorded by an imaging system. By shifting the high frequency information to the correct position and combining the low frequency information, the resolution of the reconstructed image can be improved in the process of digital representation. In the dark-field system, both the amplitude and phase of the input beams are modulated by loading different images on a spatial light modulator to generate Laguerre-Gaussian vortex beam, Airy beam and Airy beam with vortex phase. A dark- field condenser used in the system focuses these beams on the sample respectively. It is found that not only the resolution but also the contrast is enhanced.

关 键 词：全息 显微成像 结构光照明 分辨率 

分 类 号：O438[机械工程—光学工程]