2results about How to "Focus adjustment" patented technology

A zoom endoscope optical system comprises, in order from the object side to the image side along the optical axis, a front fixed lens group, a zoom lens group and a compensation lens group, the front fixed lens group comprises a first lens, a second lens and a third lens, the zoom lens group is adjustable in position and comprises a fourth lens and a fifth lens, the compensation lens group is adjustable in position and comprises a sixth lens, a seventh lens, an eighth lens and a ninth lens, the ninth lens is an aspheric lens, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens and the eighth lens are spherical lenses, compared with the prior art, the eight spherical lenses and the one aspheric lens are arranged, thereby reducing the length of the optical system, shortening the lens diameter, simultaneously assisting in correcting the imaging quality, and the aspheric lens guarantees the edge precision and improves the imaging effect of detecting the tiny defects in the pipeline.

This utility model relates to the field of lead selenide detector technology, specifically a lead selenide detector with adjustable focal length. It includes an instrument body and a base for mounting the instrument body. Two retainers are fixedly connected to the top of the base, and the instrument body is installed within the retainers. A movable plate is slidably mounted on the top of the base, and a placement frame is fixedly connected to the top of the movable plate away from the instrument body. A lens assembly is housed within the placement frame. This utility model features retainers, a movable plate, a placement frame, and a lens assembly. The lens assembly and the placement frame are connected by a plug-in joint, enabling the lens assembly to be detachable and replaceable. This allows for the replacement of lenses of different specifications according to different usage requirements, thereby adjusting the detector's focal length. Simultaneously, adjusting the distance between the lens body and the instrument body also changes the focal length of the instrument body. Furthermore, the retainers and placement frame provide a stable support structure for the instrument body and the lens assembly.