Study of 3-dimentional laser imager with wide field of view

本研究的目的是开发一种新型的高分辨率激光显微镜，具有非常广泛的视野，基于收缩过滤器技术，超前于时代。为了实现这样的激光显微镜，需要装配一个扫描透镜，即fθ透镜，采用了一种新的机器元件——收缩滤器。在我们之前的工作中，我们成功地开发了视场宽度为10mm，总放大倍数约为1000倍的激光显微镜。在目前的工作中，我们试图使激光光斑在焦平面上更精细，从3 μm到1 μm。为此，设计了fθ透镜。但是我们发现这种fθ透镜的设计是非常困难的，我们不能同时满足fθ特性和远心。远心是某些多镜头设计的特殊特性，在这种设计中，穿过物镜的所有点的主光线都是准直的。然后我们改变了我们的镜头设计，使更多的扫描宽度将从10毫米扩大到50毫米，尽管光斑直径也扩大了。而这种透镜设计的改变，是符合研制大视场激光显微镜的目的的。利用光学设计软件Code v设计了由5个光学透镜组成的fθ透镜。收缩钳子是我们自己用数控车床制造的。在组装之前测量了尺寸和形状。在光学台上测量了fθ在焦平面上的光斑等光学性能。采用波长为405 nm的激光二极管。在主扫描方向上，光斑直径在扫描宽度中心附近最小，约为12 μm，在扫描宽度两端最小，约为20 μm。另一方面，分扫描方向的激光光斑直径在整个扫描宽度上保持恒定值为12瓮。我们理解了为什么主扫描方向的激光光斑直径在扫描宽度两端变大，我们逐一检查了可能的原因。最后我们找到了原因。从而制备出具有50 mm宽视场和6 μm高分辨率的新型激光显微镜。少

The aim of this research is to develop a new type of high resolution laser microscope, having a remarkably wide field of view, based on a shrink fitter technology, ahead of the times. lb realize such a laser microscope, it is necessary to assemble a scanning lens, that is the fθ lens, by using a new machine element of shrink fitter. In our previous work, we succeeded in the development of the laser microscope that has a field of view of 10mm wide and a total magnification of about 1,000 times. In the present work we were trying to make the laser spot finer on the focal plane, from 3 μm to 1 μm. lb do this the fθ lens was newly designed. But it was found that such fθ lens design was very difficult and we were not able to satisfy both the fθ characteristics and the telecentricity simultaneously. Telecentricity is a special property of certain multi-element lens designs in which the chief rays for all points across the object lens are collimated. Then we changed our lens design so that th … More e scanning width would be broadened from 10 mm to 50 mm although the spot diameter was also broadened. This change of the lens design, however, is in accordance with the aim of development of the laser microscope having wide field of view.The fθ lens consisting of five optical lenses was designed by optical design software, Code V. Those lenses and the housing were ordered to manufacture. The shrink fitter was made by ourselves with a NC lathe. The sizes and shapes were measured before assembling them. The optical performance of the fθ such as a laser spot on the focal plane, was measured on the optical bench. A laser diode of 405 nm wave length was used. The laser spot diameters in a main-scanning direction became smallest value of 12 μm around the center of the scanning width and 20 μm at the both ends of the scanning width. On the other hand the laser spot diameter in a sub-scanning direction became constant value of 12 urn over the whole scanning width. lb understand why the laser spot diameter in the main-scanning direction became larger at the both ends of the scanning width, we checked possible reasons one by one. Finally we found out the reason. As a result the new type of laser microscope, having a remarkably wide field of view of 50 mm and a high resolution of 6 μm, could be fabricated. Less