Screen Based Apparatus for

Ultrasonic Diffraction -

Acousto optic effect

Model: HO-ED-A-01A

The Ultrasonic diffraction apparatus is used to study diffraction of light by ultrasonic waves. Ultrasonic sound refers to sound with a frequency greater than the human audible range (20Hz to 20 KHz). When an ultrasonic wave propagates through a medium, the molecules in that medium vibrate over very short distance in a direction parallel to the longitudinal wave. The apparatus consists of a graduated rail and rail carriages appropriately fitted with a laser head, an RF oscillator, a glass tank mount with crystal holder and a screen.

The ultrasonic waves generated by the transducer travels down the medium (liquid)and gets reflected at the bottom (flat glass plate) of the cell. The incident and reflected waves interfere and a stationary / standing wave pattern is formed. The pattern can be observed on a screen or a wall and we can plot diffraction pattern on a graph paper for further calculations.

Experiment Examples

To find the velocity of ultrasonic wave in liquids

The velocity of ultrasonic wave in a liquid,

V   =   ʋ ʌ

Where υ is the frequency of the crystal oscillator and Λ is the wavelength of ultrasonic wave.

We have,

Λ   =   n λ / Sin θ

Where n is the order of diffraction, λ is the wavelength of the laser used and θ is the angle of diffraction.

θ   =   tan-1 ( D / L )

D is the order length and L is the distance measured from the crystal oscillator to the detector.

To find the bulk modulus of the given liquid

The bulk modulus of the liquid,

β   =   ρV2

Where ρ is the density of the liquid and V is the velocity of the ultrasonic wave.

To find the compressibility of the liquid

The compressibility of a liquid is the reciprocal of bulk modulus,

K   =   1 / ρV2

Where ρ is the density of the liquid and is V the velocity of the ultrasonic wave.

Specification Of Piezo Electric Crystals

Dimension   :   20 mm diameter x 0.7 mm thickness

Resonant frequency fr   :   3 MHz ± 50 KHz

Resonant impedance Zm   :   ≤ 6 Ω.

Static capacitance Cs   :   570 0pF ± 15% @ 1 kHz

Dimension   :   20 mm diameter x 0.4 mm thickness

Resonant frequency fr   :   5 MHz ± 100 KHz

Resonant impedance Zm   :   ≤ 0.48 Ω.

Static capacitance Cs   :   3800 pF ± 20% @ 60 Hz/1 V

Fig: Optical system for observation of diffraction by ultrasonic waves

Features

Diode laser is used as light source

Easy to operate and portable.

5 MHz, 3 MHz Piezo electric crystals

Corrosion free

Precision design

Extended durability

Related Topics

Interference

Standing waves

Huygens' Principle

Bulk modulus

Compressibility

Scope of Supply

Optical Rail

Model No: ED-A-01A-OR
Length
:
500 mm
Material
:
Black anodized Aluminum alloy
Quantity
:
1 no.

Kinematic Laser Mount

Model No: ED-A-01A-KLM
Material
:
Black anodized Aluminum alloy
:
:
+/-4 degrees
Quantity
:
1 no.

Glass tank Mount with Crystal Holder

Model No: ED-A-01A-GMCH
Material
:
Black anodized Aluminum alloy
:
Quantity
:
1 no.

Screen

Model No: ED-A-01A-S
Material
:
Acrylic
Dimension
:
300 x 200 mm
Quantity
:
1 no.

Glass Tank

Model No: ED-A-01A-GT
Material
:
Float
Dimension
:
50 x 35 x 35 mm
Quantity
:
2 nos.

Piezo Electric Crystals

Model No: ED-A-01A-PEC
Frequency
:
3, 5 MHz
Quantity
:
1no. each

RF Oscillator

Model No: ED-A-01A-RFO
Frequency Range
:
2 - 6 MHz
Quantity
:
1no.

Diode Laser with Power supply (Red)

Model No: ED-A-01A-DLPR
Wave length
:
650 nm
Optical power
:
3 mW
Quantity
:
1no.

Accessories

Test Sample
Connecting Cables
User Manual

Glass Tank / Cuvette

Model No. ED-A-01-GT
\$ 46.00