Fundamental Structure of Surgical Microscopes
1 Mechanical System
High‑quality surgical microscopes are generally equipped with a sophisticated mechanical system for fixation and manipulation. It enables the observation and illumination systems to be quickly and flexibly moved to required positions. The mechanical system consists of a base, casters, brakes, main column, rotating arm, cross arm, microscope mounting arm, horizontal X‑Y translator and foot control panel, etc. The cross arm is usually designed in two sets, so that the observation microscope can be rapidly positioned above the surgical site over the widest possible range. The horizontal X‑Y translator accurately locates the microscope at the desired position. In addition to controlling the microscope's vertical and horizontal movement and focusing, the foot control panel can also adjust the magnification of the microscope. As the framework of the surgical microscope, the mechanical system defines the movement range of the microscope. Stability of this system must be guaranteed during operation.
2 Observation System
The observation system of a conventional surgical microscope is essentially a zoom binocular stereomicroscope. It comprises an objective lens, zoom system, beam splitter, accessory objective lens, special prism and eyepiece. Assistant cooperation is often required during surgery, so the observation system is frequently designed in a dual‑operator binocular configuration.
3 Illumination System
Microscope illumination is divided into internal illumination and external illumination. It is used for special applications such as slit‑lamp illumination in ophthalmology. The illumination system is composed of a main lamp, auxiliary lamp, optical fiber cable and other components. The light source illuminates the object from the side or above, and the image is formed by reflected light entering the objective lens.
4 Display System
With the continuous development of digital technology, surgical microscopes have gained increasingly rich functions. The surgical microscope in our hospital is fitted with a video camera display and surgical video recording system. Surgical procedures can be displayed directly on TV or computer monitors, allowing multiple people to observe the operation simultaneously. It is suitable for teaching, scientific research and clinical consultation.
