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The main difference between LX and LH in 1G (Gigabit) Fiber optic transceiver SFP lies in transmission distance and standardized definition. The two are often mixed or combined in practical applications (LX/LH), but the standard LX distance is shorter, while LH represents a longer distance.
The Core Difference between LX and LH
| Model | SFP-1GE-LX | SFP-1GE-LH |
| Standard | 1000BASE-LX (Standard) ,IEEE 802.3z standard | 1000BASE-LH (Long Haul),Supplier customization (non-standard IEEE standard) |
| Full name | Gigabit long wavelength fiber transceiver | Gigabit ultra long distance fiber transceiver |
| Transmission distance | Single mode fiber, 10km | Single mode fiber, 70km-80km |
| Center wavelength | 1310nm | 1310nm or 1550nm |
| Compatibility | Supports single mode/multimode | Usually focused on long distance single mode |
Detailed Comparative Analysis
1. Transmission distance (Distance)
- SFP-1GE-LX: Mainly designed for single mode fiber optic transmission between urban area networks, campus networks, or buildings, with a standard distance of 10km.
- SFP-1GE-LH (Long Haul): It is designed to meet the demand for ultra long distance transmission exceeding 10km, reaching 40km-70km, and even further. We can use EX or ZX for short definition.
2. Standardization definition
- SFP-1GE-LX: It is the standard Gigabit Ethernet specification (1000BASE-LX) defined by IEEE.
- SFP-1GE-LH: It is not a standard defined by IEEE. It is a general term used by optical communication suppliers to distinguish their long-distance optical modules (Long Haul).
3. LX/LH combination
In the market, it is common to see 1000BASE LX LH SFP transceivers, which usually use 1310nm or 1550nm and can transmit distances of 10km to 40km through single mode fiber, which is a compromise solution between the two.
How to choose LX or LH fiber optic transceiver?
Yingda recommend to choose the 1G fiber optic transceivers SFP by the transmission distance, detail as below:
- Distance less than 10km: 1000BASE-LX or LX/LH can be used.
- Distance of 10km-40km: Recommend to use 1000BASE-LH (also known as EX module), or even longer as 80km (ZX moules) .
In network devices, LX and LH are usually compatible (i.e. plugged into the same interface), but the fiber type (single-mode or multi-mode) and transmission distance limitations must be confirmed when using them.
Yingda is a professional fiber optic transceiver manufacturers and can provide SFP 1GE LX modules like below:
The longer distance high performance SFP 1GE LH modules like below:
