Acousto-optic deflector

An acousto-optic deflector is a useful gadget designed by utilizing acousto-optic impacts. It has actually been widely used in beam of light control, optical signal processing, optical computer, optical interaction, and also other areas.

An acousto-optic deflector is a useful tool created by utilizing acousto-optic results. It has been extensively used in beam of light control, optical signal handling, optical computer, optical interaction as well as various other fields.

Acousto-optical effect

When the ultrasonic wave circulates in the acousto-optic crystal, it will lead to the routine change of the crystal's refractive index, comparable to the generation of a stage quantity grating, as well as the incident light will certainly diffract. Altering the power as well as regularity of the ultrasonic field can efficiently control the diffracted light's direction, intensity and regularity.

L.Brillouin first anticipated the acousto-optic impact in 1922. American researchers P. Dalbye and W.ears validated the existence of acousto-optic diffraction through experiments. Subsequently, as a result of the appearance of laser, from 1966 to 1976, the concept of acousto-optical interaction and also the research study of acousto-optical tools have actually been swiftly established, amongst which Dixon's Dixon formula, W.r.kalin, and B.D.Conook's acousto-optical combined wave formula as well as I.C.Hang's theory of momentum matching as well as a mismatch have actually continuously enhanced individuals' cognition of acousto-optical effects.

C. Riam, as well as N.Nath, explained the relationship between the multi-order diffraction light as well as the first-order diffraction light in acousto-optic diffraction utilizing the coupled wave formula. They split the modes of acousto-optic activity right into Bragg diffraction as well as Raman-Nath diffraction. The acousto-optic interaction has a characteristic length of L0, and also the interaction area of the Raman Neiss acousto-optic effect is fairly brief, L ≤ L0.

The acousto-optic crystal amounts an aircraft grating, and the instructions of event light is not strict and can generate multi-level diffraction light. The interaction area of the Bragg acousto-optical impact is relatively long, L ≥ 2L0, and also the entire crystal is equivalent to a specific grating, which has strict needs on the instructions of incident light. Just the event light meeting Bragg's problem can generate diffraction light, and the advanced diffraction light is almost cancelled out, leaving only the 0 as well as ± 1 order diffraction light.

Acousto-Optic Crystals

Acousto-optic crystals with large flexible coefficient, excellent medium uniformity, small sound rate, tiny ultrasonic attenuation, wide light transmission range and also large size are needed to fabricate acousto-optic gadgets. Currently, lead molybdate (PbMoO4), Te 2 oxide (TeO2), lithium niobate (LiNbO3), Quartz and Fused Silica are mostly made use of in the audio-optical crystals. These materials have the attributes of high diffraction effectiveness and huge working bandwidth, etc. Enhancing the operational mode can attain the optimal design of the tool feature.

Working principle of acousto-optic deflector

The acousto-optic deflector mainly includes an acousto-optic tool as well as an electroacoustic transducer. Acousto-optic tool is the medium of acousto-optic communication. The electroacoustic transducer is also referred to as an ultrasonic generator. The duty is to transform electrical power into good power to produce an ultrasonic field in the tool. As an acoustic wave is an elastic wave, the proliferation of the sound wave in the medium will certainly produce elastic pressure, called the elastic-light impact.

Elastic contortion will certainly bring about a modification in the refractive index of the medium. This adjustment in the refractive index brings acoustic details. The effect amounts developing a refractive index vexing the medium with a spacing equal to the wavelength of the acoustic wave. When the ultrasonic frequency changes with the obtained signal of various frequencies, the grating interval likewise changes. Bragg diffraction happens when the beam of light goes through the refractive index grating under certain conditions.

The change of the input voltage signal of the electroacoustic transducer can alter the acoustic wave frequency and also manage the acoustic wave deflection at different angles. In Bragg diffraction, in theory, all the power of the incident beam can be converted to the diffraction beam of light, and also the diffraction effectiveness level is high.

With the advancement of optoelectronic modern technology, acousto-optic gadgets have been widely utilized in lots of fields due to their outstanding efficiency.