Acousto-Optic Tunable Filter (AOTF) | SIMTRUM Photonics Store

Applications of AOTF

• Spectral Analysis: AOTF is applicable in spectrophotometers for swiftly tuning the wavelength of the light source to measure and analyze various spectral components.
• Multi-wavelength Imaging: AOTF enables rapid switching between different wavelengths of light in a multi-wavelength imaging system, facilitating the acquisition of images across different bands for applications such as environmental monitoring and medical imaging.
• Communication System: In optical fiber communication, AOTF can be utilized for wavelength division multiplexing and demultiplexing to enhance system bandwidth and efficiency.

Main Product package list

• AOTF
• RF Driver (Optional)

Product General specifications

Model selection guide

AOTF Customization Options

Currently we can only support standard parts, due to production limitation, We can only customize Aperture size , or customer with quantity orders.

If you have any customization requirement，please email to info@simtrum.com.

Product Size and Appearance Labelling

Free Space AOTF

The Basic Composition of AOTF

1.Acoustooptic medium: usually transparent crystalline materials, such as Quartz, rubidium aluminum phosphate (RbTiOPO4), Silicon, etc.

2.Transducers: Piezoelectric crystals (such as barium titanate) convert electrical signals into ultrasonic waves.

3.Drive electronics: Provides an adjustable RF signal to drive the transducer.

Working Principle

1.Sound waves travel through a medium:

When the transducer receives the RF signal from the driving electronics, it generates ultrasonic waves.

The ultrasonic wave propagates in the acousto-optic medium, which causes the refractive index of the medium to change periodically, forming a structure similar to the grating.

2.Diffraction of light:

When the incident light passes through the acousto-optic medium, it is affected by the periodic refractive index change caused by the sound wave.

This change will cause the incident light to diffract, divided into multiple diffraction orders (such as 0, 1, etc.).

3.Wavelength selection:

By changing the frequency of the RF signal, the wavelength and frequency of the sound wave will also change, thus changing the period of the grating formed.

Because the diffraction Angle and diffraction efficiency of light are related to the grating period, different wavelengths of light diffract at different angles.

By precisely controlling the frequency of the RF signal, it is possible to selectively diffract and transmit specific wavelengths of light.

4.Beam separation:

The diffracted light of a particular wavelength can be separated by an appropriate optical element (such as a prism or lens), and the undiffracted light continues to travel along its original path.

AOTF Calculation Formula:

The acousto-optical interaction can be described in terms of the Bragg diffraction condition. By adjusting the frequency of the RF signal, Λ can be altered, thereby enabling selective tuning of λ.

• Λ represents the wavelength of the sound wave
• θ denotes the angle between incident light and diffracted light
• m signifies the diffraction order
• λ refers to the wavelength of light 

Q:Can the AOTF handle a maximal power (~300 mW for a single laser and ~ 1W when a few lasers are turning on together). 

A:Yes, usually the AOTF can handle multiple laser turn on together with a high power

Q: What is the input and output of AOTF fiber coupler head？

A: currently our AOTF only support free Space Input and output. 

Q:What is the difference between AOM and AOTF？

A:

Q:What are the main factors affecting the wavelength range of AOTF?

A:Sound velocity of an acousto-optic medium

• Quartz based AOTF: can cover a wavelength range of about 200 nm-4 µm.
• Rubidium aluminophosphate based AOTF: covers a wavelength range of about 350 nm-5 µm.

   Design of transducer and drive circuit

• Transducer efficiency: Efficient transducers are better able to convert electrical signals into sound waves, allowing for a wider range of wavelength selection.
• Driver circuit: The design of the driver circuit determines the frequency range and power of the applied RF signal, which affects the tuning range of the AOTF.

Sales Guide

If you need our technical team for guidance on product selection or customization, please help to provide below technical information, it helps to speed up the process.

AOTF Customization Options

Currently we can only support standard parts, due to production limitation, We can only customize Aperture size , or customer with quantity orders .

If you have any customization requirement，please email to info@simtrum.com

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