Applications
- Sensor System
- Spectrometer
- Instrumentation
Features
- Low Optical Distortions
- 8 Ports Integration
- High Isolation
- High Reliability
- Fail-Safe Latching
- Epoxy-Free Optical Path
- Low Cost
Product Overview
The LCFF Series fiber optic switch offers exceptional performance with ultra-broadband coverage from UV to IR. It features low optical loss, minimal temperature dependence, a high on/off ratio, vibration insensitivity, and a compact size. The switch connects optical channels via direct fiber-to-fiber coupling, utilizing an index-matching liquid to fill the small gap between fibers, which eliminates unwanted surface reflection issues. Channel switching is managed by an electrical relay, and its latching operation ensures the selected optical path is maintained even after power is removed. The switch is bidirectional and controllable via a 4.5V signal. It accommodates large-core fibers (0.2 to 0.4mm diameter) and provides transmission characteristics identical to the fiber itself. The platform is robust, insensitive to temperature and vibration, and available in 1x1, 1x2, 1x3, and 1x4 configurations. A larger format is available for 1xN applications.
This switch employs a specially formulated, non-fluorescent index-matching liquid that fills a gap of less than 5 μm. The transmission spectrum closely matches that of the fiber, avoiding additional distortion, making it ideal for spectroscopic applications and ensuring high fidelity signal transmission.
Switches designed for PM fibers transmit both polarizations identically to the fiber.
Specifications
| Parameter | Min | Typical | Max | Unit |
|---|---|---|---|---|
| Operating Wavelength | 300 | 2600 | nm | |
| Insertion Loss [1] | 0.5 | 1.0 | dB | |
| (1x1) | 0.8 | 1.2 | ||
| (1x2) | 1 | 1.8 | ||
| (1x3) | ||||
| Polarization Depended Loss | 0.1 | dB | ||
| Wavelength Dependent Loss | 0.05 | 0.1 | dB | |
| Cross Talk On/Off Ratio [1] | 35 | 45 | 50 | dB |
| Return Loss [1] | 35 | dB | ||
| Rise/Fall Time | 3 | 5 | ms | |
| Repetition Rate | 1 | Hz | ||
| Repeatability | ±0.05 | dB | ||
| Durability | 108 | Cycles | ||
| Optical Power Handling | 1 | 2 | 3 | W |
| Switching Type | Latching / Non-Latching | |||
| Operating Temperature | -5 | +60 | °C | |
| Storage Temperature | -40 | +60 | °C | |
| Fiber Type | 100, 200, 300, 400, 500, 600 Core, or equivalent μm | |||
Notes:
- [1]. Excluding Connectors. Measured @ Light source CPR<14 dB.
Note: The specifications provided are for general applications with a cost-effective approach. For specific tolerance, coverage, limit, or qualification needs, please contact Agiltron.
Mechanical Dimensions (mm)
Detailed drawings show the physical dimensions of the switch module. Key dimensions include overall length (e.g., 130 mm), width (e.g., 56 mm), and height (e.g., 21.5 mm). Mounting holes are indicated, typically M2 size with a specified depth.
Diagram showing the overall dimensions and mounting points of the fiber optic switch module.
A separate diagram illustrates the dimensions of the benchtop box, showing its length (240.0 mm), width (145.0 mm), and height (54.0 mm), along with indicator lights and connectors.
Diagram showing the mechanical dimensions of the optional benchtop control unit.
Electrical Connector Configurations
The switch coil is resistive and activated by a 5V signal (drawing approximately 40mA). Agiltron offers computer control kits with TTL and USB interfaces, including a Windows™ GUI, and an optional RS232 interface.
Latching Type – Single Coil
Application Note: Constant driving voltage enhances stability. Switches can also be driven by a pulse mode using Agiltron's recommended circuit for energy saving. Typical pulse width is 50 ms. Custom voltages (e.g., 3V) are available upon request.
| Status | OpticalPath | Electric Drive | Status Sensor | |||||
|---|---|---|---|---|---|---|---|---|
| 1x1 | Dual 1x1 | 1x2 | Pin 1 | Pin 2 | Pin 3 | Pin 4-5 | Pin 6-7 | |
| Status I | Port 1 → 1' | Port 1 → 1' Port 2 → 2' |
Port 1 → 1' | 0 | 5V Pulse | NC [3] | Open | Open |
| Status II | Dark | Dark | Port 1 → 2' | 0 | NC [3] | 5V Pulse | Close | Close |
Non-Latching Type
| Status | OpticalPath | Electric Drive | Status Sensor | |||||||
|---|---|---|---|---|---|---|---|---|---|---|
| 1x1 Transparent | 1x1 Dark | Dual 1x1 Transparent | Dual 1x1 Dark | 1x2 | Pin 1 | Pin 2 | Pin 3 | Pin 4-5 | Pin 6-7 | |
| Status I | Port 1 → 1' | Dark | Port 1 → 1' Port 2 → 2' |
Dark | Port 1 → 1' | 0 | NC [2] | NC [2] | Open | Open |
| Status II | Dark | Port 1 → 1' | Port 1 → 1' Port 2 → 2' |
Dark | Port 1 → 2' | 0 | 5V | NC [2] | Close | Close |
Functional Diagram
Illustrates the basic switching logic for 1x1, Dual 1x1, and 1x2 configurations. These diagrams show how input ports connect to output ports under different switch states.
Diagrams depicting the internal switching paths for 1x1, Dual 1x1, and 1x2 configurations.
Ordering Information
The ordering code is constructed using a prefix (LCFF-), configuration (1x1, 1x2, 1x3), test wavelength, type (Latching/Non-latching), package, fiber core size, fiber cover, fiber length, connector type, driver, and benchtop option.
| Prefix | Configuration | Test Wavelength [1] | Type | Package | Fiber Core Size | Fiber Cover | Fiber Length | Connector [1] | Driver | Benchtop [3] |
|---|---|---|---|---|---|---|---|---|---|---|
| LCFF- | 1x1 = 1 | 488 = 4 | Latching = 1 Non-latching = 2 Special = 0 |
Standard = 1 Special = 0 |
100 μm (NA0.22) = E | Bare fiber = 1 2 mm Jacket = 2 3mm jacket = 3 Special = 0 |
0.25m = 1 0.5m = 2 1.0m = 3 Special = 0 |
None = 1 FC/PC = 2 SMA = 3 Special = 0 |
Non = 1 USB = 2 RS232 = 3 TTL = 4 |
Non = 1 Yes = 2 |
| 1x2 = 2 | 630 = 6 | 200 μm (NA0.22) = F | ||||||||
| 1x3 = 3 | 780 = 7 850 = 8 980 = 9 1060 = 1 1310 = 3 1550 = 5 2000 = 2 Special = 0 |
300 μm (NA0.22) = G 400 μm (NA0.22) = H 500 μm (NA0.22) = I 600 μm (NA0.22) = J UV180nm = U Special = 0 |
Notes:
- [1]. The device is intrinsically ultra-broadband limited by the fiber's transmission. Testing at one selected wavelength is standard; testing at multiple wavelengths incurs additional cost (Special = 0).
- [2]. Regular fiber connectors have PER ~22dB. Connectors with PER >27 dB are available via a special process.
- [3]. The benchtop unit integrates modulation, driver, and power supply. It features an SMA 0-5V electrical control input port for modulation, standard FC/APC connectors for fiber input/output, and a 100-240 VAC power input. This design simplifies setup and operation.
Red indicates Special Order items.
Typical Response
Oscilloscope traces show the switching behavior. One trace illustrates a signal rise time of approximately 1.300ms and a fall time of 2.310ms. Another trace shows a rise time of 3.704kHz frequency. These measurements demonstrate the speed and characteristics of the switch's operation.
Oscilloscope screenshots showing signal rise and fall times, frequency, and voltage levels during switch operation.
Command List
The device supports serial communication with a Baud Rate Setting of 9600-N-8-1. Commands are sent in hexadecimal format. For example, a command to switch channels (e.g., 0x01 0x12 0x00 x) is acknowledged with a success message. A command to check the version (e.g., 0x01 0x02 0x00 0x00) returns a version code (e.g., 0x01 0x02 0x41 0x30).
| Command/Echo | Comments |
|---|---|
| BaudRate Setting: 9600-N-8-1 | |
| CMD: 0x01 0x12 0x00 x (HEX) Echo: 0x01 0x12 0x00 x (HEX) |
/Switch to CH, x: 1, 2, 3 /Successed |
| CH 1 2 3 |
Status I1-O1 I1-O2 I1-O3 |
| CMD: 0x01 0x02 0x00 0x00 Echo: 0x01 0x02 0x41 0x30 |
/Check Version |
Typical Fiber Transmissions
A graph illustrates the typical attenuation (in dB) versus wavelength (in nm) for both Infrared (IR) and Ultraviolet (UV) light. The graph shows broad spectral coverage, with attenuation varying across the UV to IR range. The IR curve generally shows lower attenuation, especially at longer wavelengths, while the UV curve exhibits more variation and higher attenuation in certain regions.
Graph showing typical attenuation (dB) versus wavelength (nm) for IR and UV light transmission.
Application Notes
Fiber Core Alignment
Optimal attenuation depends on precise core-to-core alignment when connectors are mated. This is particularly critical for shorter wavelengths and smaller fiber core diameters, where misalignment can significantly increase loss. Connectors from different vendors may not mate perfectly, especially angled APC connectors.
Fiber Cleanliness
Fibers with smaller core diameters (less than 5 μm) require extreme cleanliness. Contamination at fiber-fiber interfaces, combined with high optical power density, can lead to significant optical damage, often requiring re-polishing or connector replacement.
Maximum Optical Input Power
Due to small fiber core diameters and high photon energies at short wavelengths, the damage thresholds are substantially reduced compared to standard 1550nm fiber. To prevent damage to fiber end faces and internal components, the optical input power should not exceed 20 mW for wavelengths shorter than 650nm. Agiltron produces a special version with an expanded core side at the fiber ends to increase power handling capability.
