When, in the 1980s, I became interested in the spermatology of fish under the light microscope, active spermatozoa were only visible thanks to their head presenting a sort of “tremor.” This situation was quite frustrating given the lack of possible information regarding the motor part called flagellum. We decided to apply simple technologies, including photography. Due to the high speed of the moving fish flagellum, the microscope illumination used a pulsed light strobe combined with a dark field microscope to record the flagellum image despite its small diameter (< 0.5 μm). Then came high-speed cinematographic microscopy up to 200 fps, as well as video cameras. At the end of the 1990s, an automatic moving object video tracking system began to be commercialized (CASA) with main advantages such as (a) a large number of cells tracked, which greatly improves statistics, (b) computer assistance allowing an automatic analysis that provides many motility parameters. Nevertheless, CASA systems are still unable to provide information about fish sperm flagella that move fast. During the 1990s, analog video camera technologies allowed acquisition of flagellum images with high resolution for detailed analysis. Since the 2000s, the use of high-speed video cameras allows the acquisition of images at a much higher resolution and frequency, up to 10,000 frames per second. Since it became possible to visualize the flagella in motion, a noble function was added to that of a propeller: that of a rudder with what a spermatozoon responds to specific signals delivered by the egg for its guidance. In the future, one can wish that an automatic flagella movement analyzer will become functional. This brief anthology puts forward the large amount of progress accomplished during past 40-year period about spermatozoa movement analysis, especially in fish.

在 1980 年代，当我对光学显微镜下的鱼的精子学产生兴趣时，由于头部呈现出一种“震颤”，所以才能看到活跃的精子。鉴于缺乏有关称为鞭毛的运动部分的可能信息，这种情况非常令人沮丧。我们决定应用简单的技术，包括摄影。由于移动鱼鞭毛的速度很高，显微镜照明使用脉冲光频闪结合暗场显微镜来记录鞭毛图像，尽管其直径很小（< 0.5 μm）。然后是高达 200 fps 的高速电影显微镜以及摄像机。1990 年代末，一种自动运动物体视频跟踪系统开始商业化（CASA），其主要优点是：（a）跟踪大量细胞，这大大改进了统计，(b) 计算机辅助允许提供许多运动参数的自动分析。尽管如此，CASA 系统仍然无法提供有关快速移动的鱼类精子鞭毛的信息。在 1990 年代，模拟摄像机技术允许获取高分辨率的鞭毛图像以进行详细分析。自 2000 年代以来，高速摄像机的使用允许以更高的分辨率和频率采集图像，最高可达每秒 10,000 帧。由于可以将运动中的鞭毛可视化，因此螺旋桨的功能增加了一项崇高的功能：作为方向舵，精子对卵子发出的特定信号做出反应以进行引导。将来，人们可以希望一种自动鞭毛运动分析仪能够发挥作用。