Acousto-Optic Modulator
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Description
An Acousto-Optic Modulator (AOM) functions by Bragg scattering light from a periodic density modulation (longitudinal acoustic wave) in a crystal, typically TeO2. The scattering process shifts the frequency of the optical carrier by the frequency of the acoustic carrier in a direction that depends on the orientation of the light relative to the wavevector of the travelling acoustic wave. This frequency shift can be thought of as the doppler shift from scattering off of moving acoustic wavefronts. The phase of the diffracted light is directly related to the phase of the acoustic wave, allowing for coherent phase and amplitude modulation of the optical signal. Applications of AOMs include scanning lasers, generating frequency shifted light for heterodyne detection, and shaping femtosecond laser pulses.
Vendors
Brimrose
This is one of the good AOMs i have used and its slightly expensive than NEOS. I used an AOM for 1550nm femtosecond pulses for pulse shaping. It is working beautifully for many years.
Crystal Technology
Looking at the application notes, it appears that they use a smaller crystal and not useful for femtosecond pulse shaping.
IntraAction
- MabuchiLab vendor review: Expect very poor, but consistent, customer service. Only one employee can help you, and he is often out of his office and never returns phone calls. When you finally get to speak to him, he seems knowledgeable and your conversation will leave you feeling optimistic. However, he will always tell you that he has to either email or fax you a price quote, and this will never happen unless you continually bother him to do so. This scenario has played out many times for members of MabuchiLab. We have continued to endure it because their prices are good, but we recently discovered NEOS's low-priced line of AOMs...
- Update: I met a representative of IntraAction at Photonics West in January 2008, and he apologized for never sending me the quotes that I requested. He promised that he would send them to me, but I have not yet received them.
Isomet
- MabuchiLab vendor review: Respond quickly to email price quote requests. Prices for low-end AOMs are somewhat high. May or may not respond to questions about non-standard applications.
Karthick: Isomet's MID-IR AOM at 5um is used for mid-ir pulse shaper for 2D-IR spectroscopy. Probably optimised for good efficiency at 5um. It requires water cooling and more care than other AOMs.
NEOS Technologies
- MabuchiLab vendor review: Their AOM representative is very friendly and helpful on the phone. She is knowledgeable and returns phone calls and emails promptly. NEOS has a lab on-site that is willing to test the performance of their products in non-standard applications. We have been pleasantly surprised by the reasonable prices of their low-end AOMs.
