PHENOMENALLY HIGH EFFICIENCYNON-CONTACT ULTRASOUND
TRANSDUCERS

www.secondwavesystems.com
sales@secondwavesystems.com

Non-contact – gas/air coupled -- ultrasonic transducers offered by SecondWave
represent the epitome of transducer design. These devices have been underdevelopment since 1978, reaching perfection in 1997 with US and several
international patents. NCU transducers are based upon piezoelectric phenomena
and feature perfect Z-matching for 100% transduction in air from <100 kHz to 10MHz.
The new NCU transducers generate immense acoustic pressure in airbetween <100 kHz to 5 MHz. This is the key to Non-Contact Ultrasound andthe magnitude of this development. Imag in e 2.0 MHz tr ansmissio n in 25 mmsteel (6 orde rs of ma gnitud e Z mis match) with only one burs t 16 Vpp a nd 6 4dB a mplific ation!

500 kHz. 16 vpp. ZERO dB amplification

160140
ACOUSTIC PRESSURE (Pa/V)

100 kHz. 16 vpp. ZERO dB amplification

1 MHz 50 mm

120
500 kHz 50 mm

10080

100 kHz 50 mm

1 MHz. 16 vpp. ZERO dB amplification

60200 kHz 50 mm

402000255075100

125150175200225250275

TRANSDUCER TO REFLECTING TARGET DISTANCE IN AIR (mm)300

2 MHz. 16 vpp. ZERO dB amplification

3 MHz. 16 vpp. ZERO dB amplification

Total freedom from to uc h or con taminat ion
Effic iency riv alin g contact tra nsduc ers
High frequency -- <100 kHz to >10 MHz
Robus t c ons tru ction

10 MHz. 16 vpp. ZERO dB amplification

NCU TRANSDUCERS
SPECIFICATIONSFEATURE

SPECIFICATIONSFrequency Range
Sensitivity<100 kHz to >10 MHz
Phenomenally high in air, ~30 dB lower
than contact transducers
Generally, >60 dB
Nominally, between 30 to 50% of BCF– broader bandwidths, also available<1 mm to >76 mm active diameter
Planar, point and cylindrically focused
Aluminum protected by clear plastic
cover
Axially mounted standard BNC
90% RH
70 deg C
Successfully tested up to 50 bars
Robust and factory suitable

Signal to Noise Ratio
Bandwidth
Dimensional Range
Geometrical Configuration
Housing
Co-axial Connector
Maximum Humidity
Maximum Temperature
Maximum Gas Pressure
Construction

PLANAR TRANSDUCERSORDERING INFORMATIONCATALOG #FREQUENCY

ACTIVE DIAMETER (mm)NCT-101
NCT-201

100 kHz

25.0
50.0

NCT-52
NCT-102NCT-202

200 kHz

12.5
25.0
50.0

NCT-25
NCT-55
NCT-105
NCT-205

500 kHz

6.3
12.5
25.0
50.0

NCT110
NCT-210
NCT-510
NCT1010

1.0 MHz

3.2
6.3
12.5
25.0

NCT120
NCT-220
NCT-520

2.0 MHz

3.2
6.3
12.5

NCT130
NCT-230
NCT-530

3.0 MHz

3.2
6.3
12.5

NCT140
NCT-240
NCT-540

4.0 MHz

3.2
6.3
12.5

NCT150
NCT-250
NCT-550

5.0 MHz

3.2
6.3
12.5

For assistance and other variables, please contact us.

FOCUSED NON-CONTACT TRANSDUCERS
Non-contact transducers can also be configured to generate focusingmechanism in air. In the following table we have provided a few point
focused transducers.
Should you need cylindrically focusedtransducers, simply change the suffix “P” to “C.” The numeral following
the suffix is the Relative Aperture (RA, focal length/active diameter).
Very small RA transducers are difficult to produce, however, in special
cases we have made transducers with RA of 1.

ORDERING INFORMATIONMODEL #FREQ.

ACTIVE(mm)25

FOCAL
LENGTHIN AIR(mm)FOCAL
POINTIN AIR(~mm)

HALF
ANGULAR
APERTURE(~o)

100150200300

7.0
10.0
7.0
10.0

7.2
4.8
7.2
4.8

NCT-102-P4
NCT-102-P6
NCT-202-P4
NCT-202-P6

200 kHz

NCT-105-P4
NCT-105-P6500 kHz

25100150

2.8
4.2

7.2
4.8

NCT-210-P4
NCT-510-P4
NCT-510-P6

1.0 MHz

6.3
12.5

255075

1.4
1.4
2.1

7.2
7.2
4.8

NCT-220-P4
NCT-520-P4
NCT-520-P6

2.0 MHz

6.3
12.5

25
5075

0.7
0.7
1.0

7.2
7.2
4.8

NCT-230-P4
NCT-530-P4
NCT-530-P6

3.0 MHz

6.3
12.5

255075

0.5
0.5
0.7

7.2
7.2
4.8

NCT-240-P4
NCT-540-P4
NCT-540-P6

4.0 MHz

6.3
12.5255075

0.35
0.35
0.55

7.2
7.2
4.8

NCT-250-P4
NCT-250-P6

5.0 MHz

6.3

2538

0.28
0.42

7.2
4.850

For assistance and other variables, please contact us.

AIR/GAS VELOCITY COMPENSATIONNON-CONTACT TRANSDUCERS
In order to increase the stability of ultrasound signals in NCU mode
sometimes it may be necessary to compensate for velocity fluctuations
in air caused by thermal currents, humidity variations, and turbulent airflow. This is especially true for very accurate thickness, velocity,transmittance, reflectance, and density measurements. While our NCA
1000 with planar transducers is capable of providing accuracies within+/- 1%, with Velocity Compensation (VC) transducers it can beincreased by an order of magnitude. VC transducers feature constantdistance built-in reflectors in front of active transducers from which theNCA 1000 constantly determines the air velocity to apply to allmeasurements.

ORDERING INFORMATIONCATALOG #FREQ.

ACTIVE(mm)

TRANSDUCERINTERNALREFLECTOR AIRDISTANCE(mm/round-tripToF, s)

BEAM EXITAPERTUR
E
DIAMETER(mm)

NCT-102-VC

200 kHz25.050/290

19NCT-55-VC
NCT-75-VC
NCT-105-VC

500 kHz

12.5
19.0
25.0

20/115
20/115
20/115101419NCT-510-VC
NCT-710-VC

1.0 MHz

12.5
19.0

10/58
10/58

1014

NCT-520-VC

2.0 MHz

12.5

5/29

10For assistance and other variables, please contact us.