A zoom lens is a special lens that can change the magnification of the lens through the adjustment of the internal mechanism without replacing the lens. This kind of lens is widely used in microscopes, cameras, telescopes and other optical equipment, especially in occasions where continuous zoom is required, such as scientific research, medical treatment, security and other fields.

However, although the magnification of the zoom lens is adjustable, in practical applications, because the object distance (the distance from the test object to the lens) is often fixed, or due to the limitations of the use of the environment can not be arbitrarily changed, which will bring some limitations to the use of the lens. In order to solve this problem, there is a need for some additional parts to adjust the test object distance, so that the zoom lens can be better adapted to different use of the environment and needs.

Adjustable additional objective lens is a kind of add-on specially designed for the zoom lens. Through its own adjustment mechanism, it can change the distance between the additional objective lens and the main lens, thus changing the equivalent objective distance of the whole lens. In this way, even without changing the position of the test object, the lens can be optimized for imaging by adjusting the additional objective lens.

The following is an example of zoom lens accessory inspection using an adjustable additional objective lens:

Preparation:

1、Prepare an optical equipment equipped with a zoom lens (e.g. microscope, video camera, etc.);

2, Prepare an adjustable additional objective lens and its mounting tool;

3, prepare a standard test pattern or object for evaluating the imaging quality of the lens.

Attach the additional objective lens:

Attach the adjustable additional objective to the zoom lens using the mounting tool, making sure it is securely mounted and correctly positioned.

Adjust the additional objective lens:

Without changing the position of the test object, change the distance between the additional objective lens and the main lens by adjusting the adjustment ring or knob on the additional objective lens.

Observe the imaging effect and find the best imaging condition by fine-tuning the position of the additional objective lens.

Optimization and Adjustment:

Based on the test results, the mounting position and adjustment of the additional objective lens is optimized.

If needed, the zoom lens itself can be fine-tuned to further improve the imaging quality.

Through the above steps, the adjustable additional objective lens can be effectively used to test and optimize the performance of the zoom lens, making it better suited to different usage environments and needs.

To meet different needs, a variety of adjustable objective lenses have been designed for the 6.5X and 12.5X series of zoom lenses.