Analysis of Insertion Loss and Attenuation of Fiber Optic Patch Cord

1. Is the insertion loss of the fiber optic patch cord as small as possible?

Customers often request to make optical fiber optic patch cords with extremely small insertion loss. For example, two days ago, a customer ordered an APC jumper with an insertion loss of less than 0.1dB. We can produce such high-grade jumpers, but the cost is much higher than telecom-grade jumpers. So is the insertion loss of the fiber optic patch cord as small as possible? the answer is negative.

Optical fiber optic patch cord is used as a device for jumping signals and connecting optical paths. Although the smaller the insertion loss is, the smaller the attenuation is, but blindly pursuing excessive optical parameter requirements, the material and process of fiber optic patch cord must be greatly improved, which requires high costs. The cost, the price/performance ratio is not suitable. In the scheme design of the optical system, the design power of the light source will have a reserved amount, which is higher than the actual application power. Through optical attenuators, optical splitters and other devices, the power will be reduced to the power value required for actual use.

Therefore, the insertion loss of the fiber optic patch cord used for connection can meet the requirements of the carrier level. If you want to improve the performance of the jumper, such as interchangeability, reliability, and consistency, it is recommended that customers use a fiber optic patch cord with excessive interference (3D) on the end face of the jumper, which is a high-standard jumper that is currently used internationally. 

2. Will the optical fiber optic patch cord attenuate after a long time?

As for the fiber optic jumper, it is used as a jumper from the device to the fiber optic cabling link. It has a thicker protective layer and is generally used for the connection between the optical transceiver and the terminal box. Fiber optic patch cords are similar to coaxial cables, but without the mesh shield. In the center is the glass core for light propagation.

In a multimode fiber, the diameter of the core is 15 μm to 50 μm, roughly equivalent to the thickness of a human hair. The single-mode fiber core has a diameter of 8 μm to 10 μm. The core is surrounded by a glass jacket with a lower refractive index than the core to keep the fiber inside the core. There is a thin plastic jacket on the outside to protect the envelope.

Will jumpers age and attenuate after a long period of use like circuits? In fact, if you understand the structure of the fiber optic jumper, you will not have such doubts. The middle is the fiber core, and the outside is the glass envelope, and there is a layer of plastic cover on the outside for protection. Over time, the outer plastic jacket will age, and after the protective layer is damaged, the transmission rate of the jumper will naturally decrease.

There are several points to note when using optical fibers:

1. After using the optical fiber optic patch cord, the optical fiber connector must be protected with a protective sleeve. Dust and oil will damage the coupling of the optical fiber.

2. Do not bend or circle excessively during use, as this will increase the attenuation of light during transmission.

3. If the optical fiber connector is dirty, you can use a cotton swab dipped in alcohol to clean it, otherwise it will affect the communication quality.