Quartet – Multipurpose Receiver
Rugged, Versatile and Sensitive All Surface Types
Our multi-purpose laser receiver is suited for a wide range of acoustic and ultrasonic applications from the laboratory to the factory and available in the visible or infrared. Based on our patented multi-channel random quadrature detection technology, the system is designed for remote detection of sub-nanometer displacements. The system offers high sensitivity, requires low to no maintenance, can be fitted with a variety of laser wavelengths, and is capable of rapid scans and measurements. The Quartet was born of a research and development grant by NASA and the National Science Foundation.
Description
The Quartet
is a multi-purpose laser receiver well suited for a wide range of acoustic and ultrasonic applications from the laboratory to the factory and available in the visible or infrared. Based on our patented multi-channel random quadrature detection technology, this receiver is designed for remote detection of sub-nanometer displacements. It offers high sensitivity, requires low to no maintenance, can be fitted with a variety of laser wavelengths, and is capable of rapid scans and measurements.
Robust & Versatile
Because the technology does not require control over the length of the optical path within the system, the Quartet is not subject to stability issues common to most long cavity and path-stabilized interferometers. It does not require high accuracy optical components or positioning, making it exceptionally rugged.
Fiberized Optical Head
A relatively small and versatile fiberized optical head is easily mounted to fit a variety of measurement conditions and can be set-up for a wide-range of stand-off distances. Its front lens can be easily changed or replaced if necessary
Measurement Precision
The Quartet produces an analog signal that is proportional to surface displacement.
High Sensitivity on all Surface Types and Materials
Thanks to its multiple detectors and high transmission optics, the Quartet accomplishes efficient light collection and thus, high sensitivity. This continues to be true when the system is fitted with a moderately powerful laser thanks to low noise detectors and electronics. By detecting and processing many speckle interference signals, the Quartet achieves a stable demodulated signal even when processing a highly speckled beam. This means that it can perform measurements on any kind of surface, including rough, porous, rusted or mirror-like surfaces.
Inspection on Rapidly Moving Objects
Streamlined electronic processing allows the Quartet to perform single shot measurements on fast-moving objects, at speeds up to meters per second.
Not Wavelength Dependent
The Quartet can be fitted with a range of internal laser wavelengths ranging from visible to infrared.
Signal Indicators
Incorporated within the system are visual and audible signal indicators designed to help the user optimize their measurement setup. The Quartet also includes an internal calibration signal allowing for a calibrated output at 100mV per nanometer of displacement.
Beam Chopper (Optional Upgrade)
The beam chopper is an optional feature which allows the system to be used on materials with poor heat conductivity, such as plastics or carbon fiber materials without damaging the surface. A perforated disk synchronized with the generation laser “chops” the beam at a regular interval in order to prevent the sample from being exposed to continuous laser power. This feature does not affect the quality of the signal as it allows the laser to be used at full power, in contrast to alternative solutions such as using continuous but low laser power systems. Once installed, the chopper can be turned on and off to suit the application. This upgrade is compatible with new generation Quartets and is easily installed by replacing the top cover of the system.
Specifications
Specification
MCRQ Technology: The idea behind Multi-Channel Random Quadrature was to develop a laser-ultrasound technology with a robust, compact design and a large depth-of-field, capable of functioning effectively in a wide range of environments without loses in sensitivity, including on rough surfaces. With support from the National Science Foundation and NASA, we developed the Quartet. By collecting and processing a multitude of speckles, the Quartet is fully functional in environments which would otherwise be unsuitable for most other receivers and can perform measurements on all surface types.
NESD (Noise Equivalent Surface Displacement) | 2. 10-6 nm/Hz1/2 |
Detection Bandwidth Upper limit | Up to 80 MHz |
Standard Detection Bandwidth Lower limit | 1 MHz |
Suitable CW Laser power | 500mW to 3W internal laser Option: Internal chopper for reduced average power |
Laser wavelength | 532nm (Visible), 1064nm (IR) and 1550nm (IR) |
Fiber | Multimode / Length to be specified when ordering |
Spot diameter on sample | 50µm to 1.5mm (depend on stand-off & wavelength) |
Optical stand- off | From 70mm to a few meters |
Diameter of collecting aperture | 2” (50mm) |
Analog Outputs | Calibrated output – 100mV/nm Direct output, Calibration level and DC level |
Options | Beam Chopper / 2D scanning set-up including PC, software, digitalization card and X-Y translations |
Electrical Requirements | 110V / 220V – 50Hz / 60Hz |
Demodulation Dimensions | 185 x 320 x 370mm |
Optical Head Dimensions | 65 x 85 x 170 mm |
Demodulation Weight | 10kg |
Optical Head Weight | 0.75kg |