How an aom works an aom is a crystal connected to a piezoelectric transducer. Highfrequency, resonant acoustooptic modulators fabricated in a. The frequency of laser light can be shifted in the rf range through the use of an acousto optic frequency shifter aofs. Free space acousto optic modulators mhz electronics. In this paper, 3d finite element and transfer matrix methods allow investigating the electrical, mechanical and optical resonances of an. The increased bandwidth allows for chirp control in highspeed data communication. In many laser atom cooling experiments, acoustooptic modulators aom. The following 24 files are in this category, out of 24 total. A guide to acoustooptic modulators nickerson devices. Pdf a practical problem that arises when using acoustooptic modulators aoms to scan the laser frequency is the. Isomet corp, 5263 port royal rd, springfield, va 22151, usa.
Doublepass acoustooptic modulator system aa opto electronic. The principles of operation and the applications of each method are different. An introduction to acoustooptics scott e pollack physics 7810 fundamentals of optics and lasers university of colorado, boulder december, 2002 abstract this paper is a brief introduction to acousto optic. The existence of an interaction between light and sound was discovered by brillouin in the. Maldonado department of electrical engineering the uni y ersity of texas at arlington arlington, texas 1 3. An acoustooptic modulator aom, also called a bragg cell or an acoustooptic deflector aod, uses the acoustooptic effect to diffract and shift the frequency of light using. The zero order is the beam directly transmitted through the cell. For simple gray level control, the best approach is to characterize the transfer function and apply the appropriate. The light is proportionally directed into a primary intense diffraction. Pdf doublepass acoustooptic modulator system researchgate. Rp photonics encyclopedia acoustooptic modulators, aom.
Because the acoustic signal is sinusoidal, a moving. Characterization and optimization of the laser diffracted by an. A very fast 100 khz acousto optic scanning system, which relies on two counterpropagating acoustic waves with the same frequency modulation, is proposed and experimentally demonstrated. An acousto optic modulator can be used to shutter a laser beam on and off. We report the design and characterization of high frequency, resonant acoustooptic modulators aom in a mems. Pdf files for board schematic and layer views, folder containing pdf files. Acoustooptic components use a range of different materials in a variety of. In many laser atom cooling experiments, acousto optic modulators aom are used to modulate a laser beam frequency close to an electronic resonance of the atoms. Our acousto optic modulators are optimized for low scatter and high laser damage threshold. The research indicates that the acousto optic modulators trends in addition to the magnitude of each distinct segment in the acousto optic modulators market. Acousto optic material selection a variety of acousto optical materials are used for acousto optic modulators depending on the laser parameters such as wavelength, polarization, and power density. Comsol mode shape of the compound radial expansion mode of the ring resonator at 1.
The authors describe acousto optic modulators for optical fibers, fabricated by the deposition of. The research indicates that the acousto optic modulators trends in addition to the magnitude of each distinct segment in the acousto optic modulators. Acousto optic modulator 41145 an acousto optic modulator aom, also called a bragg cell, uses the acousto optic effect to diffract and shift the frequency of light using sound waves usually at radiofrequency. Controlling light in complex media beyond the acoustic. This is one of the most useful properties of the acoustooptic modulator. The rf driver features all the necessary components to drive the modulator. Table 2 is a summary of the properties and figure of merit for most common materials used for the neos technologies acousto optical modulators. Acoustooptic infiber modulator using acoustic focusing. The modulator element consists of an optical crystal with a piezo transducer. Acousto optic modulator aom uses a sound wave to modulate an incoming beam of light to optimize optical systems and devices. This page was last edited on 11 november 2018, at 17. Basic acousto optic modulator and driver rf 1st order output 0th order input laser beam intensity modulation sep bragg modulator driver ao modulator key parameters.
Special attention is given to design procedures for the entire range of acousto optic devices and a wide variety of applications for these devices is also described. An acousto optic modulator aom, also called a bragg cell or an acousto optic deflector aod, uses the acousto optic effect to diffract and shift the frequency of light using sound waves usually at radiofrequency. An electrooptic modulator eom is an optical device in which a signalcontrolled element exhibiting an electrooptic effect is used to modulate a beam of light. Wita stwosza 57, 80952 gdansk, poland received 25 june 2001. Rise time, modulation rate, beam diameter, and power handling needs of the application need to be understood in order to identify the best acousto optic modulator and rf driver solution. This interaction effect based on the diffraction of light by periodic modulation of the refractive index of a transparent optical material, which. A is a world leader in the manufacturing of quality acousto optic and radio frequency devices. Bragg 1st 0th rf sep vel input m12t80l6tc acousto optic modulator 1217 all specifications subject to change without notice quality assured. Free space acousto optic modulators the brimrose free space acousto optic modulator aom with rf driver is used to vary and control laser beam intensity. Mar 03, 2012 applications and commercial products electrooptic modulator phase modulator is a high performance, low drive voltage external optical modulator designed for customers developing next generation transmission systems.
To support the onoff signal, the rise time of the modulator system has to. Theoretical and experimental analysis of the nearbragg acousto optic effect. An introduction to acoustooptics scott e pollack physics 7810 fundamentals of optics and lasers university of colorado, boulder december, 2002 abstract this paper is a brief introduction to acoustooptic phenomena. Introduction to acousto optic modulators by olen rambow september 20 omycroft. Finally, basic bulk electrooptic modulators are described in the fourth section, modulator devices including some design considerations and performance criteria. Introduction to acoustooptic modulators by olen rambow september 20 omycroft. We present to the reader the mathematical formalism used to describe this phenomena as well as the common. Acousto optics is a phenomenon which deals with the interaction of light optics and sound acoustics. Osa detailed analysis of the longitudinal acoustooptical. This paper will describe the principles of operation and the applications of acousto optic bragg cells and electro optic. This angle is in the plane of deflection and relative to a normal from the input optical surface. Aa optoelectronic offers its customers solutions from prototype design to large volume manufacturing thanks to its internal resources.
The discussion presented in this chapter applies to any electrooptic material, any direction of the applied voltage, and any direction of the wave vector. It describes the change of refractive index of an optical medium due to the presence of an acoustic wave. Since the grating modulation depends on the acoustic drive, the combined analysis provides a more efficient operation. Acoustooptic application note modulator model 3000 series this data sheet is issued to provide outline information only and crystal technology, inc. A acousto optic modulator has a nonlinear transfer function, and as a result, care must be exercised when applying an analog modulation signal to a acousto optic modulator. The new luminar is a nextgeneration spectrometer that is highly acousro optic yet comes in a small size, offers lowpower consumption and has no brimroe parts. A device utilizing acoustooptic interaction ultrasonically to vary the amplitude or the phase of a light beam. What is electrooptic modulator an electrooptic modulator eom is a device which can be used for controlling the power, phase or polarization of a laser beam with an electrical control signal. The ability of the acousto optic modulator to shift the frequency of a laser light beam by a precise and stable amount is crucial to production of a beat note from two light beams in this experiment. An acousto optic modulator aom is a device which can be used for controlling the power of a laser beam with an electrical drive signal.
Light from a coherent optical source is focused to a beam waist within the optical. Free space acoustooptic modulators mhz electronics. In our experiment, the acousto optic interaction length of the aom designed primarily for operation in such a mode was 2 mm. It is shown that the aom design can be considerably simplified and its size can be minimized if the ramannath diffraction mode is the dominant diffraction mode of aom. Acoustooptical effects principles and applications. Adjustment of the rf output power is best done with the series 230 driver connected to the acousto optic modulator. An acousto optic modulator aom, also called a bragg cell or an acousto optic deflector aod, uses the acousto optic effect to diffract and shift the frequency of light using sound waves.
An aom consists of a piezoelectric transducer pzt bonded to an optical medium glass or crystalline. This paper presents an overview of the characteristics of several types of multibeam modulators based on optical diffraction including multifrequency ao, multiport ao, and e0 modulator. Optical channel beam waist in aom approximately 150. The driver maximum output power is factory preset to the specified level 1 watt.
Pdf acoustooptic infiber modulator using acoustic focusing. Background acoustooptic devices are based on the periodic modulation of the optical. Part i operation of the acousto optic modulator simple analysis of acousto optic deflection. Within these devices incoming light bragg di racts o acoustic wavefronts which propagate through a crystal. The rf driver features all the necessary components to drive the modulator with analog or. Where to buy acoustooptic modulators, aom, rf driver. Light from a coherent optical source is focused to a beam waist within the optical medium composed of low loss uv grade fused silica. The model h600 series multichannel acoustooptic modulators allow 32 independent beams to be modulated at data rates in excess of 20 mbs. Provided are an acousto optic element, an acousto optic element array, and a display apparatus including the acousto optic element array. An acousto optic modulator beam switching device for use in recording and display systems comprises a source of collimated light.
Also known as bragg cell explanation of acoustooptic modulator. Jul 01, 2009 optic modulator types electrooptic modulator acoustooptic modulator magnetooptic modulator 3. Transmission characteristic simulation of high frequency. By applying a digital ttl signal to the modulator s driver digital modulation input, the rf energy applied to the modulator is modulated on and off. Low cost fast frequency switching driver for acoustooptic. Files are available under licenses specified on their description page. Such a device allows the modulation of the light intensity.
Acoustooptic effect and its use in signal processing. The interaction frequencies between longitudinal acoustic waves and fiber bragg grating are numerically and experimentally assessed. The dominant devices to perform these tasks are acousto optic and electro optic modulators. It is electronically programmable using a microprocessor connected to the brimrose rf driver unit. Applying a radiofrequency electrical drive to the pzt launches a highfrequency traveling sound wave in the medium. Multichannel devices with more than two inputs can be special ordered. This angle is in the plane of deflection and relative to a normal from the input optical. Us4321564a sequential beam switching of acoustooptic. The acousto optic modulator the acousto optic modulator is based on the elasto optic effect, in which a material strain causes a change in the refraction index of the material. By carefully orientating the laser with respect to the sound waves the beam can be made to reflect off the acoustic wavefronts bragg diffraction.
Develops the underlying theory of acousto optics from first principles, formulating results suitable for subsequent calculations and design. An acoustooptic modulator aom is a device which can be used for controlling the power of a laser beam with an electrical drive signal. Kwiek department of acousto optics and laser physics, institute of experimental physics, university of gdansk, ul. Optical setups require extreme precision, and researchers must often implement modulators to adjust the frequency, amplitude, wavelength, and direction of their laser beam. Acoustooptic modulator 1217 all specifications subject to change without notice quality assured. Integrated acoustooptic device modules and applications. An acousto optic modulator aom can be used to slowly or rapidly modulate the intensity of a laser beam for example, a variation of this component is specifically designed for use as a qswitch inside a laser cavity. We also offer fibercoupled acousto optic modulators. This acts like a phase grating, traveling through the crystal at the acoustic velocity of the material and with an acoustic wavelength dependent on the frequency of the rf.
Connect the rf output bnc jack to an acousto optic modulator or a 50q, rf load, if it is desired to measure the modulator rf output power. Alultibeam acoustooptic and electrooptic modulators. A device using a bulk acousto optic interaction eg. Low cost fast frequency switching driver for acoustooptic modulators used in laser cooling. Noahs acousto optic modulator driver is available to. The acousto optic modulator aom is a simple bragg cell that uses the acousto optic effect to diffract and shift the frequency of light using sound waves, which is used in lasers for qswitching, telecommunications for signal modulation, and in spectroscopy for frequency control. The modulator is available in single and dualchannel configurations. Znse saturable absorber sa was reported for the first time. In the preceding chapter, we have shown that modulators and switches can be made by using the electro optic effect to produce a gratingshaped variation of the index of refraction.
The way by which one can make sure the operating mode of the modulation is by observing the comsol results of the designed model of proposed acousto optic modulator aom. In case of the acoustooptic effect, the strains are produced by an acoustic wave excited in a transparent medium. When the strain is generated by an acoustic compression or rarefaction, an aom is formed. The first order is the diffracted beam generated when the laser beam interacts with the acoustic wave. These advancements include the analytical treatment of complex interaction geometry, preparation of waveguide materials, design and fabrication of wideband bragg modulators and deflectors bragg cells, and the demonstration of a number of simple applications. Acoustooptic modulator article about acoustooptic modulator. They are used in lasers for qswitching, telecommunications for signal modulation, and in spectroscopy for frequency control. In an acousto optic modulator aom a laser beam is caused to interact with a high frequency ultrasonic sound wave inside an optically polished block of crystal or glass the interaction medium. The acoustooptical intensity modulator consists of an ao modulator element and a driver electronics unit. Here, we introduce the acoustooptic transmission matrix aotm, which is an ultrasonicallyencoded, spatiallyresolved, optical scatteringmatrix. Mccarron december 7, 2007 1 introduction acousto optic modulators aoms are useful devices which allow the frequency, intensity and direction of a laser beam to be modulated. Mccarron december 7, 2007 1 introduction acousto optic modulators aoms are useful devices which allow the frequency, intensity and direction. A is a world leader in the manufacturing of quality acoustooptic and radio frequency devices. All structured data from the file and property namespaces is available under the creative commons cc0 license.
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