In terms of light transmission, glass optical fibers have many advantages over plastic optical fibers. Here are five reasons why glass is the best choice for light transmission in medical devices such as endoscopes and dental instruments.

1.Excellent lighting performance

Optical fibers are the basis for flexible and rigid light guides, and fibers fabricated from glass provide the highest light transmission performance. Glass has an extremely high color rendering index, which means that the wavelength of light entering and leaving the fiber or light guide changes very little. This can show the most realistic color and doctors can use glass optical fiber light guide to observe human tissue faithfully. Glass fibers can have numerical apertures up to 1, allowing more light to enter and travel along the fiber, resulting in a larger field of view and the ability to illuminate a larger area with a smaller fiber bundle. In contrast, due to the limitations of material properties, the numerical aperture of plastic optical fibers can only reach a maximum of 0.5.

2.Sturdy and bendable

Glass is very strong, but very thin glass can become very flexible. The combination of these two properties means that glass fibers used in light guides can be as large as 30 micrometers in diameter (less than half the thickness of a human hair). Such a small diameter enables the tight bend radii required for highly flexible movement in the endoscope. In contrast, very thin plastic optical fibers are typically 500 microns in diameter, and in most cases 1 mm (1000 microns) or more. In imaging applications, a single glass fiber can be as small as 4 microns in diameter, enabling extremely high pixel resolution. This means that detailed, clear images can be transmitted from one end of the fiber optic bundle to the other. As with endoscopes or rigid fiber optic dental light guides, fiber optic light guides are easily autoclaved or reprocessed at 134 degrees Celsius. Optical fibers made from specialty glass are more flexible and flexible than plastic optical fibers. They have a significantly higher modulus of elasticity.

3. Stable at high temperature

Since glass remains stable at temperatures up to 350°C, flexible glass fiber optic bundles or rigid light guides can easily withstand autoclaving environments up to 134°C. This makes glass ideal for light transmission in reusable instruments such as dental instruments or endoscopes that require cleaning and sterilization. Instruments containing plastic optical fibers cannot be autoclaved, as such fibers typically only withstand temperatures up to 80°C.

4. More design options

Due to the extremely small diameter of glass fibers, a large number of individual fibers can fit into a relatively small fiber bundle. This enables complex geometries to be achieved with small fiber bundles. When used as a light source for disposable endoscopes, the small diameter fiber can be positioned around the camera in a specific shape to reduce camera over saturation. The use of glass fiber optic bundles also allows light from a single light source to be transmitted to multiple locations along several smaller branches. Glass fiber optic bundles can mix red, green, and blue LED light to generate uniform white light at the other end. Because glass fibers are so thin, more glass fibers can fit into the same diameter bundle than thicker polymer fibers. The higher the number of fibers, the more uniform the light output.

5. Excellent chemical resistance

Due to the high chemical resistance of glass, it does not react with cleaning agents, detergents, acids, alkalis, solvents or adhesives. This makes the glass components durable and easy to clean. Glass is also inert, meaning there is no risk of allergic reactions, as it does not provoke any immune response in the body. Plastics can react with a variety of chemicals, sometimes causing an immune response in the body. Many plastics cannot be used in low temperature medical device processing, such as plasma sterilization, because they react with the hydrogen peroxide used in such processes.