MSV-400 Microscope Scanning Vibrometer - Features

The MSV-400 Microscope Scanning Vibrometer is the successor to the award-winning MSV-300 for full-field vibration analysis of very small objects such as MEMS optical switches. Based on the laser Doppler principle, a HeNe laser maps the vibrational response of the structure with a lateral resolution of down to 1 µm. MSV-400 can achieve picometer vibration resolution and up to 20 MHz bandwidth.

 

MEMS and Microstructure Vibration Analysis

 
The MSV-400 Microscope Scanning Vibrometer was developed expressly for the vibrational analysis of MEMS (Micro-Electro-Mechanical Systems) devices and other microstructures. These devices find numerous applications in the automotive, medical, bio-chemical and aeronautic industries. As a consequence there is a huge demand for standardized MEMS testing for both packaged and unpackaged devices (single die and wafer-level testing). Polytec's MSV-400 is the ideal tool for a quick and accurate motion analysis of MEMS devices. For wafer-level testing, the MSV-400 can easily be mounted onto manual or fully automated probe-stations.

 

    
Key Features

  • Full-field vibration mapping through the optics of a microscope

  • Frequency-domain and time-domain measurements

  • Full out-of-plane frequency response information

  • Frequency range from 0 Hz up to 1 MHz (20 MHz optional)

  • High resolution video imaging for animated visualization of time-domain and frequency-domain data

  • Picometer displacement resolution (optional) for out-of-plane motions

  • Microscopic laser spot size (e.g. 1 µm for 40X lens)

  • Compatible with most popular CCD port equipped microscopes

  • Modular design is easily upgraded to an MMA-400 Micro Motion Analyzer

  • Scripting control for automation

    
Benefits of Laser-Doppler Vibrometry

 
Only Laser Doppler Vibrometry (LDV) provides the full picture of a device’s out-of-plane vibrational behavior. Measurements do not have to be performed at discrete frequencies. Instead, vibration data is available resulting from any excitation waveform over the full bandwidth of the Vibrometer. LDV enables the analysis of nonideal or non-linear systems.

 

    
The System


A MSV-400 Microscope Scanning Vibrometer system consists of the optical scanning system, an OFV-551 Fiber-Optic Interferometer, the OFV-5000 Vibrometer Controller and the Data Management System (DMS), a workstation with A/D-converter and software. A dual beam-splitter module (OFV-072) is mounted onto the microscope and the optical fiber is coupled into the optical path via the micro-scanning  module (OFV-073). The latter employs an external unit to control two ultra-precise piezostages for scanning the laser beam through the microscope's optics. Simultaneously a progressive scan camera (VCT-101) provides a live video stream for the DMS. The laser is moved, not the object. A steady, live video image during the whole measurement is the benefit.

 

    
Two Versions

 
The MSV-400 Microscope Scanning Vibrometer is available in a standard version MSV-400-M2 and a high-frequency version MSV-400-M2-20. In both cases a high-end Polytec OFV-5000 Vibrometer Controller is used for the demodulation of the velocity and the displacement signals. The MSV-400-M2, with an upper frequency limit of 1 MHz, has both digital and analog velocity  decoders. The MSV-400-M2-20 comes with either a high frequency (HF) velocity decoder with an upper frequency limit of 10 MHz or a HF displacement decoder with an upper frequency limit of 20 MHz.  

 

    
Hardware and Software

 
The MSV Data Management System (DMS) consists of a Windows® 2000 based PC (XP on request) in an  industrial housing, hardware for scanner control, video and data acquisition, as well as the MSV-400 software suite. The standard version PC (PSV-W-400-M2) contains an IEEE 1394 Fire-Wire adapter, an internal signal generator board, a dual-channel D/A-converter for the scanning control and a 1 MHz-bandwidth 2-channel A/D conversion board for data acquisition. A PC-based digital demodulation with down to 1 pm displacement resolution is available  as an option. A 2-channel data acquisition board as well as an external or internal signal generator with 40 MHz bandwidth are used for the high-frequency version PSV-W-400-M2-20. The system software comes with the same outstanding features as the PSV-400 system for macroscopic scanning. Advanced Point Selection (APS) Professional software for defining scan points on the test object in any density combination and coordinate system  (polar, cartesian, hexagonal or arbitrary) is a standard feature of the MSV-400 system. Up to 40,000 measurement points deliver in-depth information about the device. The results are animated directly on the video image in 3D.

 

    
Modular Features and Upgrades

 
Of course, the OFV-551 Fiber-Optic Interferometer can be used as a single point vibrometer together with the OFV-5000 Controller when it is disconnected from the optical microscope scanning system. For differential  measurements through the microscope, the optical scanning system can be extended with a second beam splitter and a manual optical 2-axis positioning system. For these differential measurements an OFV-552 Dual-Fiber Interferometer must be used instead of the OFV-551. By adding in-plane capability through integration of the PMA-400 Planar Motion Analyzer, the MSV-400 can be upgraded to a complete MMA-400 Micro Motion Analyzer and a full 3-D  characterization becomes possible. For measurements on devices sensitive to high light intensities an optional laser dimmer is available for all Fiber-Optic Interferometers.

 

    


MSV-400 Microscope Scanning Vibrometer




MSV-400 Optical Setup