How to Choose the Right Fiber Optic Patch Cord?

When selecting a fiber optic patch cord, It is better to know the following factors:

• Type of Fiber: Choose single-mode for long distances and multi-mode for shorter distances.​

• Connector Type: Ensure the patch cord connectors are compatible with your equipment (e.g.SC, LC, FC, ST).
• APC or UPC
• Cable Length: Measure the distance between the devices to select an appropriate cord length.

• Application Environment: If the cable is to be used outdoors or in harsh conditions, select one with a suitable jacket
• material (e.g., UV-resistant or fire-retardant).

APC and UPC are types of fiber optic connector end-face polishing methods. They both play a crucial role in ensuring the efficient transmission of optical signals in fiber optic connections. The primary differences between them lie in the polishing angle of the connector's end-face and their reflection characteristics. Below are the detailed differences:

1. Polishing Angle and End-Face Shape

UPC (Ultra Polished Connector):

End-face Shape: The end-face of the UPC connector is flat, and the polishing method is a flat polish.

Reflection Characteristics: Because the end-face is flat, the reflection loss of UPC connectors is relatively high, typically around -50 dB.

APC (Angled Polished Connector):

End-face Shape: The end-face of the APC connector is angled, typically at an 8-degree angle, also known as angled polish.

Reflection Characteristics: Due to the angled end-face, APC connectors effectively reduce light signal reflection. The reflection loss is typically better than -60 dB, offering superior performance, especially in high-quality communication environments that require low reflection.

2. Return Loss

UPC: The return loss is typically around -50 dB. Since the end-face is flat, the signal reflection at the fiber connector junction is relatively high, which is suitable for most conventional communication systems.

APC: The return loss is typically -60 dB or better. The angled polish significantly reduces signal reflection, making it ideal for applications where signal quality is critical, such as in television broadcasting, data centers, and long-distance communication systems.

3. Application Scenarios

UPC:

Suitable for general-purpose fiber optic networks and short-distance communication.

Commonly used for standard network equipment, fiber-to-the-home (FTTH), and communication environments where extremely low reflection is not a strict requirement.

APC:

Due to its low reflection characteristics, APC is widely used in high-precision and high-performance fiber optic communication systems, such as for long-distance transmission, television broadcasting, data centers, and high-quality fiber optic networks.

Especially suitable for environments that require low reflection loss, reducing signal interference and improving signal stability.

4. Color Differentiation

UPC: Typically uses blue connectors.

APC: Typically uses green connectors. This color coding helps distinguish between the two different polishing types.

5. Cost and Performance

UPC: Has a lower cost and performs well enough to meet the needs of most general fiber optic communications.

APC: Has a relatively higher cost but offers superior reflection suppression, making it suitable for environments with higher performance requirements.