- Editorial: Happy New Year 2010!
- 4 questions to the CTO: Flavio Heer on Technology Trends and Fascinating Projects
- New Product Announcement Q4/09: The HF2 Ultra-high Stability option
- New Application Note: Electrical Impedance Spectroscopy for Single-Cell Analysis
- Tips & Tricks: Frequency Sweeping with the HF2 Lock-in Amplifier
Editorial: Happy New Year 2010!
Welcome to the 2nd Zurich Instruments Newsletter!
This issue features an interview with Flavio Heer, CTO of Zurich Instruments, with insights into technology trends and market feedback. We present a new product, a thorough revision of the website, and a brand new application note on single-cell Microfluidics. Finally we introduce the Tips & Tricks toolbox as a regular contribution to this newsletter and present the company agenda for 2010 (don't miss us at one of these events).
Thank you for your interest in Zurich Instruments and its products!
4 questions to the CTO: Flavio Heer
You are trained as a physicist, how did you become so interested in circuits?
During my studies as a physicist I was focused on integrated micro-sensors. At one point I got my hands on a temperature sensor whose read-out circuit was based on the so called sigma-delta technique. I became so fascinated by the beauty of this circuit that I decided to become an analogue circuit designer. Now that I am both a physicist and an electrical engineer, it's great to have these qualifications for designing scientific instruments. I appreciate circuit design as much as I enjoy the contact to the people in their labs.
In your opinion, what are the current technology trends in scientific instrumentation?
A main trend is clearly in relation to higher frequencies and higher bandwidths. People are investigating smaller objects, an example being smaller oscillators with higher resonant frequencies, or for example smaller features in living cells such as RNA and DNA. In atomic-force microscopy (AFM) for example, many scientists have a requirement for faster scanning, measuring harmonics or operating cantilevers in higher modes. Here again higher frequencies are required with faster readout rates (smaller time constants), and then in addition to this a requirement for several frequencies in parallel, this could be considered a second trend.
This second trend, working parallel on several frequencies is also used in impedance spectroscopy. Here, people are analyzing the dielectric properties of single cells as they flow through a microfluidic channel. The analysis needs to take place in a short moment of time and on several frequencies in parallel, in order to receive a comprehensive dielectric fingerprint of the cell. By using this so-called flow-through impedance spectroscopy, it is possible to sort the cells (e.g. neuron or glial cells), assess the cell viability, or the level of infection.
A third trend is the increasing digitization. Our customers notice that the digital nature of ZI instruments is very beneficial as soon as they connect the device to a PC. A high-speed USB interface and device control, useable via virtually any programming language (e.g. LabVIEW, Matlab, C, ...) makes data acquisition and control loops a seamless process, unlike the situation in the past. This results in the user having fewer devices in his laboratory setup, which effectively simplifies the challenge of taking measurements.
How is customer feedback analyzed and integrated into the product roadmap?
Customer feedback is the best way to improve your products and to outline the market trends. We actually log all received input into our database and we use this information on a day-to-day basis to support our decision making. We also appreciate critical feedback, as it helps in the evolution of Zurich Instruments into a company with premium customer support. We also collect customer input to generate example of code (for instance LabVIEW virtual instruments) which we publish and make available to all customers if we think there is a general interest. Finally the market feedback is providing shape to our new product roadmap. We have several new products in the pipeline which we will announce soon.
What has been your most remarkable customer project?
We have many customers in impedance spectroscopy, atomic force microscopy, and the MEMS fields, all of this work has been truly fascinating. One particularly remarkable project that I could mention is a beam position monitor and controller, in a low-energy accelerator. The beam positioning is a key parameter in these systems and the use of a lock-in amplifier would improve the signal-to-noise ratio significantly. Such a beam position monitor records the position of the beam between 2 plate capacitors (one for X- one for Y-direction). Since the HF2LI has 2 differential inputs, the 2 plate capacitors can be connected directly. The low-frequency outputs are used to control the beam position by charging a deflection plate capacitor as required. A real-time control algorithm running inside the HF2LI closes the loop and keeps the beam in the centre. I can't wait to see the results from this project.
New Product Announcement Q4/09
The HF2 Ultra-high Stability option
Many scientists are not able to rely on climate controlled laboratories or stable temperatures conditions at the location of their measurement setup. Temperatures can range from 20 degrees in winter to 30 degrees in summer. Other scientists are concerned about instrument aging and would like to achieve long recalibration intervals. These users can now consider the HF2 Ultra-high Stability (HF2-UHS) option available for both the HF2 Lock-in Amplifier and the HF2 Impedance Spectroscope.
The HF2-UHS provides an ovenized temperature stabilized quartz oscillator, with extreme temperature stability, minimal phase noise characteristics, reliable short term stability and great aging performance. Compared to a standard oscillator, the most relevant specification parameters are better by one order of magnitude. The specification improvement will hold at all frequencies up to 50 MHz, and it is particularly large at frequencies of below 1 kHz.
All precision critical applications like Atomic Force Microscopy (AFM), semiconductor characterization, micromechanical system (MEMS) analysis or conducting nanotubes, profit from the HF2-UHS option. Zurich Instruments is the only lock-in instrument vendor that provides a temperature stabilized reference oscillator, this provides further proof of our commitment to excellence for our customers.
For more information, please visit our website.
New Application Note
Electrical Impedance Spectroscopy for Single-Cell Analysis
Electrical impedance spectroscopy allows the reliable analysis of the characteristics of biological cells which depend on signal amplitude and frequency. Current measurements can be correlated to previously calibrated data to recognize cells of 2 or more populations.
The HF2 Impedance Spectroscope distinguishes itself from lock-in amplifiers and other impedance analyzers in the following ways:
- dedicated to fast dynamic signals: very low time constants (below µs) and high sample rate to the host computer to allow for the capturing of very short events
- 2 integrated signal generators in the frequency range from µHz to 50 MHz, whereas some high-frequency lock-in amplifiers do not feature any signal generation outputs at all
- integrated multi-frequency, boosting the pattern recognition capability of the cell detection unit
- integrated microprocessor, to run custom code written in C, such as in the control of AC dielectrophoresis
Scientists using the HF2 Impedance Spectroscope profit from the improved accuracy of a digital instrument covering a frequency range that used to be measurable only with analogue instrumentation.
Tips & Tricks
Frequency Sweeping with the HF2 Lock-in Amplifier
How quickly can a frequency sweep with the HF2 Lock-in Amplifier be carried out? Does the signal drop during sweeping due to parameter updating?
The frequency response sweeper is a standard feature of the HF2 Lock-in Amplifier. The sweeping process is continuous. There are no pauses or discontinuities in the signal generated. The sweeping speed is provided by the required frequency resolution and sweeping bandwidth. Working with for instance a 100-Hz frequency resolution, theoretically demands an integration period of around 2 ms per measurement point. 10-Hz frequency resolution will take 10-times longer or about 20 ms per measurement point. The HF2LI operates close to these theoretical limits.