Fiber Coupled Acousto-Optic Modulator/Shifter Low Loss
(1.4dB, 350 to 2300 nm, 80 MHz, all fiber types) (patent pending)
DATASHEET
The AOMF Series Fiberoptic Acousto-Optic Modulators deliver high-speed optical intensity modulation and wavelength shifting with superior performance. Based on a proprietary patent-pending design, they feature low insertion loss (~1.2 dB), high extinction ratio (>62 dB), high polarization extinction ratio (>30 dB), low power consumption, and high optical power handling up to 10 W - unmatched by other vendors. The AOMF operates by acoustically generating an optical grating inside the crystal using a side-mounted piezo actuator driven at its resonance frequency for maximum efficiency. As light passes through the crystal, it is diffracted by the grating, with maximum intensity at the Bragg-aligned exit angle. The driving electronics modulate the acoustic amplitude, controlling the optical attenuation. Response speed is determined by the resonance frequency, with available options at 80 MHz and 200 MHz; the achievable modulation bandwidth is below the resonance frequency. The AOMF supports a wide wavelength range from 350 nm to 2400 nm, is compatible with all fiber types, and offers competitive cost. The device operates in a normally opaque state and becomes transparent under Bragg diffraction conditions, which occur over a narrow wavelength band where diffraction efficiency is maximized. It inherently produces a positive frequency shift, with negative shift options available upon request. The AOMF design features fiber optic collimators aligned to an acousto-optic crystal, with no epoxy in the optical path, ensuring maximum stability and long-term reliability.
Features
- Low optical Loss
- High Power
- Low Cost
- Stable
- All Fiber Compatible
Applications
- Fiber Lasers
- Pulse Picker
- Sensor
Specifications
| Parameter | Min | Typical | Max | Unit |
| Center Wavelength | 450 | 1550 | 2300 | nm |
| Wavelength Bandwidth | ±30 | nm | ||
| Acoustic Frequency | 80 | MHz | ||
| Modulation Bandwidth | DC | 19 | MHz | |
| Wavelength Shift | 80 | MHz | ||
| RF Control Resolution | 1 | MHz | ||
| Insertion Loss [1] | (1030nm~1550nm) | 0.8 | 1.4 | 2.5 dB |
| (450nm~980nm) | 1.2 | 2 | 3 dB | |
| Polarization Dependent Loss | 0.2 | 0.5 | dB | |
| Extinction Ratio (On/Off) [2] | 50 | 55 | 65 | dB |
| Rise/Fall Time [3] | 15 | 55 | ns | |
| Return Loss [4] | 45 | 50 | 55 | dB |
| Voltage Standing Wave Ratio | 1.2:1 | |||
| Polarization Extinction (PM) | 18 | 20 | 25 | dB |
| Average Optical Power | 0.5 | 20 | W | |
| Input Impedance | 50 | Ω | ||
| RF Power [5] | 2.5 | 3.5 | W | |
| Electrical Interface | SMA | |||
| Ultrasonic Velocity | 4200 | m/s | ||
| Operating Temperature | -10 | 65 | °C | |
| Storage Temperature | -45 | 85 | °C | |
| Weight | 26 | g |
Notes:
- [1] Without connector. Each connector typically adds 0.2-0.3dB, RL increase by 5dB, and ER reduces by 2dB. 1dB is for 80MHz 80ns rise/fall with special order. PM connector key is aligned to the slow axis as a default. Insertion Loss refers to output - input at ON state. Other wavelength band the loss may be higher.
- [2] For Single Mode only, multimode reduces depend on mode filled ratio. ER refers to output power ratio between ON/OFF states.
- [3] (10%-90%). The rise/fall and bandwidth are related to the beam size, small beam has higher insertion loss. In another word, fast response with larger bandwidth will add insertion loss.
- [4] 50dB is standard for SM, 45dB for 50/125.
- [5] The device is designed to be operated at 2.5W and meet the spec, but can handle a maximum of 3.5W with sufficient cooling.
Note: The specifications provided are for general applications with a cost-effective approach. If you need to narrow or expand the tolerance, coverage, limit, or qualifications, please click this link.
Rev 08/10/25
Mechanical Dimensions (mm)
AOM
Diagram showing the dimensions of the Acousto-Optic Modulator (AOM). The device has fiber optic connectors on both ends and an SMA connector on the side. Key dimensions are indicated.
*Product dimensions may change without notice. This is sometimes required for non-standard specifications.
Electrical/Computer Connection
Diagram illustrating the AOM Driver unit. It shows input and output ports, including SMA connectors for modulation input and RF output, and a power input. Dimensions are provided.
*Product dimensions may change without notice. This is sometimes required for non-standard specifications.
Ordering Information
| L | □ | □ | □ | □ | □ | □ | □ | □ | □ | □ | |
| Prefix | Type | Wavelength | Insertion (1) | Optical Power | Fiber Type | Fiber Cover | Fiber Length | Connector | PER (2) | Wavelength Shift | Benchtop (3) |
| AOMF- | 80MHz = L Special = 0 | 1060nm = 1 1550nm = 5 1310nm = 3 980 nm = 9 850 nm = 8 780 nm = 7 630 nm = 6 530 nm = A 450 nm = 4 2000nm = 2 Special = 0 | 2.5dB = 1 1.6dB = 2 1.5dB = 3 15ns R/F = A 25ns R/F = B | 0.5W = 1 5W = 2 10W = 3 20W = 4 30W = 5 | Select fiber below | 0.9mm tube = 3 Special = 0 | 0.25m = 1 0.5m = 2 1.0 m = 3 Special = 0 | None = 1 FC/PC = 2 FC/APC = 3 SC/PC = 4 SC/APC = 5 ST/PC = 6 LC/PC = 7 5WFC/PC = H 10WFC/PC = A | Non = 1 18dB = 2 20dB = 3 25dB = 4 29dB = 5 | -80MHz = 1 +80MHz = 2 | Non = 1 Yes = 2 |
[1] Without connector, each connector add 0.3dB. For 1310-1550nm. Short wavelength and >1900nm, the loss is higher. The default version is optimized for low loss with rise/fall times under 55 ns. Version A is tuned for faster response but with higher loss, while Version B offers moderate rise/fall times with more loss than the default.
[2] Polarization extinction ratio only for PM fiber.
[3] The benchtop integrates the modulator, driver, and power supply. Front Panel: SMA 05V electrical control input port for precise modulation. Fiber input and output ports with standard FC/APC connectors. Back Panel: 100-240 VAC power input for global compatibility and a Power switch for easy on/off control. This all-in-one design simplifies setup and operation.
Marked in red on special order
Fiber Type Selection Table:
| 01 SMF-28 | 34 PM1550 | 71 MM 50/125um | |||
| 02 | 35 PM1950 | 72 MM 62.5um | |||
| 03 | 36 PM1310 | 73 | |||
| 04 SM450 | 37 PM400 | 74 | |||
| 05 SM1950 | 38 PM480 | 75 | |||
| 06 SM600 | 39 PM630 | 76 | |||
| 07 780HP | 40 PM850 | ||||
| 08 SM800 | 41 PM980 | ||||
| 09 SM980 | 42 PM780 | ||||
| 10 Hi1060 | 43 | ||||
| 11 SM400 | 44 PM405 | ||||
| 12 | 45 PM460 |
Benchtop Box Mechanical Dimension
Diagram showing the mechanical dimensions of the benchtop unit, including front, side, and perspective views.
*Product dimensions may change without notice. This is sometimes required for non-standard specifications.
Setup Instructions
- Connect a laser with a wavelength matched to the specified part number to the fiber input.
- Connect the modulator to the accompanying driver using the provided cable.
- Connect a DC power supply to the driver (refer to the AOM driver datasheet for detailed specifications).
- Connect the control signal to the SMA input port.
- The fiber optical output amplitude and repetition rate will vary according to the electrical control signal.
Application Notes
Fiber Core Alignment
Note that the minimum attenuation for these devices depends on excellent core-to-core alignment when the connectors are mated. This is crucial for shorter wavelengths with smaller fiber core diameters that can increase the loss of many decibels above the specification if they are not perfectly aligned. Different vendors' connectors may not mate well with each other, especially for angled APC.
Fiber Cleanliness
Fibers with smaller core diameters (<5 μm) must be kept extremely clean. Contamination at fiber-fiber interfaces, combined with the high optical power density, can lead to significant optical damage. This type of damage usually requires re-polishing or replacement of the connector.
Maximum Optical Input Power
Due to their small fiber core diameters for short wavelength and high photon energies, the damage thresholds for the device are substantially reduced compared to the common 1550 nm fiber. To avoid damage to the exposed fiber end faces and internal components, the optical input power should never exceed 20 mW for wavelengths shorter than 650 nm. Agiltron produces a special version to increase the power handling by expanding the core side at the fiber ends.
Modulation Response (Top Optical/Bottom Electrical)
Graphs showing the modulation response of the Acousto-Optic Modulator at different frequencies (1 kHz, 1 MHz, 5 MHz, 10 MHz). The top trace represents the optical output power, and the bottom trace represents the electrical control signal.
Acoustic Frequency
The operation of an acousto-optic modulator is based on the Bragg diffraction generated by an acoustic wave (traveling refractive grating) inside a crystal. The Acoustic Frequency is fixed for each device. A RF voltage of the acoustic frequency is applied to the piezoelectric actuator attached to the crystal generating the acoustic wave. The higher the frequency, the higher the cost to make and higher the power consumption.
Modulation Bandwidth
An optical intensity modulator can be achieved by a driving circuitry in which the acoustic intensity inside the crystal varies with an input modulation signal. A typical acoustic driver output is shown below: a RF Input electrical signal modulates the intensity profile of the carrier oscillations (acoustic frequency), resulting in a modulated driving signal, which leads to an output optical intensity similar to the RF input. The acoustic frequency intrinsically determines the rise/fall of the optical modulation. The Modulation Bandwidth is proportional to the acoustic frequency. The optical response can be optimized to a certain extent via the driving circuit such as digital or analog.
Optical Wavelength Shift
Due to an energy exchange, all acoustic optical devices apply a frequency shift to the diffracted output beams. These optical wavelength shifts are very small and proportional to the acoustic frequency. Depending on the selected Bragg angle, these devices will either up-shift or down-shift the laser light by the frequency of the applied RF signal.
Typical Attenuation vs Control Signal for 200 MHz AOM
Graph showing the typical attenuation versus control signal for a 200 MHz Acousto-Optic Modulator. It plots Average Output Power (a.u.) against Modulation (V) for DC and various AC frequencies.
Typical Stability (@ -20dBm with DC and 1kHz AC control. Fluctuation < 0.1dB)
Graphs illustrating the stability of the Acousto-Optic Modulator under DC and 1 kHz AC control signals at -20dBm output. The graphs show Output (dBm) versus Time (hr), indicating minimal fluctuation.
