1. The imaging scale of the lens should be consistent with the CCD target scale of the industrial endoscope camera. As mentioned above, there are 1 inch, 2 / 3 inch, 1 / 2 inch, 1 / 3 inch, 1 / 4 inch, 1 / 5 inch and other standards.

2、镜头的分辩率 描绘镜头成像质量的内在方针是镜头的光学传递函数与畸变，但对支持而言，需求了解的仅仅是镜头的空间分辩率，以每毫米能够分辩的黑白条纹数为计量单位，计算公式为：镜头分辩率Ｎ＝１８０／画幅格局的高度。因为工业内窥镜摄像机ＣＣＤ靶面巨细已经标准化，如１／２英寸摄象机，其靶面为宽6.4mm＊高4.8mm，１／３英寸摄象机为宽4.8mm＊高3.6mm。因而对１／２英寸格局的ＣＣＤ靶面，镜头的分辩率应为３８对线／mm，对１／３英寸格局摄象机，镜头的分辩率应大于５０对线，摄像机的靶面越小，对镜头的分辩率越高。

2. The inherent principle of lens resolution to describe the imaging quality of lens is the optical transfer function and distortion of lens. However, for support, what we need to know is only the spatial resolution of lens. Taking the number of black and white stripes that can be resolved per millimeter as the measurement unit, the calculation formula is: lens resolution n = 180 / height of frame pattern. Because the size of CCD target surface of industrial endoscope camera has been standardized, for example, the target surface of 1 / 2-inch camera is 6.4mm wide and 4.8mm high, and that of 1 / 3-inch camera is 4.8mm wide and 3.6mm high. Therefore, for 1 / 2 INCH CCD target, the resolution of the lens should be 38 pairs of lines / mm. For 1 / 3 inch camera, the resolution of the lens should be more than 50 pairs of lines. The smaller the target of the camera, the higher the resolution of the lens.
               

3、镜头焦距与视界视点 依据工业内窥镜摄象机到被监控方针的距离，挑选镜头的焦距，镜头焦距f确定后，则由摄象机靶面决定了视界。

3. Firstly, the focal length of the lens is selected according to the distance from the industrial endoscope camera to the monitored target. After the focal length f is determined, the visual field is determined by the target plane of the camera.

4、光圈或通光量 镜头的通光量以镜头的焦距和通光孔径的比值来衡量，以Ｆ为标记，每个镜头上均标有其大的Ｆ值，通光量与Ｆ值的平方成反比关系，Ｆ值越小，则光圈越大。所以应依据被监控部分的光线改变程度来挑选用手动光圈还是用主动光圈镜头。

4. Aperture or luminous flux the luminous flux of a lens is measured by the ratio of the focal length of the lens to the luminous aperture. Marked by F, each lens is marked with its larger f value. The luminous flux is inversely proportional to the square of the F value. The smaller the F value is, the larger the aperture is. So we should choose the manual aperture or the active aperture lens according to the light change degree of the monitored part.