聚焦纤维透镜系统在激光散斑测量中的应用

GRADIENT-INDEX OPTICAL SYSTEM IN SPECKLE PHOTOGRAPHY

在使用相干光做光源时,所产生的激光散斑尺寸受相对孔径的限制,影响其检测灵敏度。本文提出一种新型透镜——聚焦纤维透镜,它具有高数值孔径,低 F 数。使用这种透镜可使激光散斑尺寸变小,从而提高探测灵敏度。尤其在显微放大系统中有着广泛的应用。

When coherent light source is used,small limiting apertures of micro- scope cause speckle.Thus,a high optical signal-to-noise ratio and low F/NO.s are required which can be provided under given geometrical con- stants,particularly by gradient-index rod lenses imaging systems with high numerical aperture and low F/No.s and which are proportional to the spe- ckle spot size,and are required in speckle photography.This result can be achieved by using the same gradient-index rod lenses for both imaging and illumination.