Dreher A W, Bille J F, Weinreb R N
Appl Opt. 1989 Feb 15;28(4):804-8. doi: 10.1364/AO.28.000804.
Laser scanning tomography can be used to assess retinal nerve fiber layer thickness and optic disc topography of the human eye. A pinhole is located at a plane conjugate to the focal plane of the scanning laser beam. This so-called confocal configuration assures that only the light originating from the illuminated focal plane on the retina passes through the pinhole and is detected by the photomultiplier. Consequently, images with high spatial resolution in all directions are obtained. An active optical system (active mirror) further improves the lateral/depth resolution of the laser tomographic scanner. By partially compensating for the optical aberrations introduced by the cornea and lens, the active optical system allows the illuminating beam to be enlarged to 6 mm, thus improving depth resolution twofold.
激光扫描断层扫描可用于评估人眼的视网膜神经纤维层厚度和视盘地形图。针孔位于与扫描激光束焦平面共轭的平面上。这种所谓的共焦配置确保只有来自视网膜上被照亮焦平面的光穿过针孔并被光电倍增管检测到。因此，可获得各个方向上具有高空间分辨率的图像。一个有源光学系统（有源镜）进一步提高了激光断层扫描仪的横向/深度分辨率。通过部分补偿角膜和晶状体引入的光学像差，有源光学系统可将照明光束扩大到6毫米，从而使深度分辨率提高两倍。
