1. The imaging size of the lens shall be consistent with the size of the CCD target surface of the industrial endoscope camera. As mentioned above, it has specifications of 1 inch, 2 / 3 inch, 1 / 2 inch, 1 / 3 inch, 1 / 4 inch, 1 / 5 inch, etc.

2、镜头的分辨率描述镜头成像质量的内在指标是镜头的光学传递函数与畸变，但对拥护而言，需要了解的仅仅是镜头的空间分辨率，以每毫米能够分辨的黑白条纹数为计量单位，计算公式为：镜头分辨率Ｎ＝１８０／画幅格式的高度。由于工业内窥镜摄像机ＣＣＤ靶面大小已经标准化，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。因此对１／２英寸格式的ＣＣＤ靶面，镜头的低分辨率应为３８对线／mm，对１／３英寸格式摄象机，镜头的分辨率应大于５０对线，摄象机的靶面越小，对镜头的分辨率越高。

2. The resolution of the lens is the internal index describing the imaging quality of the lens, which is the optical transfer function and distortion of the lens. However, for supporters, what needs to be understood is only the spatial resolution of the lens. Taking the number of black-and-white stripes that can be distinguished per millimeter as the measurement unit, the calculation formula is: lens resolution n = 180 / height of frame format. As the size of CCD target surface of industrial endoscope camera has been standardized, such as 1 / 2-inch camera, its target surface is 6.4mm wide * 4.8mm high, and 1 / 3-inch camera is 4.8mm wide * 3.6mm high. Therefore, for 1 / 2 inch format CCD target, the low resolution of the lens should be 38 pairs of lines / mm. For 1 / 3 inch format camera, the resolution of the lens should be greater than 50 pairs of lines. The smaller the target surface of the camera, the higher the resolution of the lens.

3、镜头焦距与视野角度根据工业内窥镜摄象机到被监控目标的距离，选择镜头的焦距，镜头焦距f确定后，则由摄象机靶面决定了视野。

3. Lens focal length and field of view angle firstly, the focal length of the lens is selected according to the distance from the industrial endoscope camera to the monitored target. After the lens focal length f is determined, the field of view is determined by the target surface 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。所以应根据被监控部分的光线变化程度来选择用手动光圈还是用自动光圈镜头。

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 with F. each lens is marked with its large F value. The luminous flux is inversely proportional to the square of the F value. The smaller the F value, the larger the aperture. Therefore, manual aperture or automatic aperture lens should be selected according to the light change degree of the monitored part.