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No. 1, January 2002



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AR4000 Laser Distance Measurement Sensor


The AR4000 laser distance measurement sensor, its use, and its principle of operation are described. The sensor measures absolute distance to a target surface by emitting a continuous modulated laser beam and collecting light reflected from the surface. The collected light is converted to an electrical signal, amplified, AC coupled, and inverted. This signal is then used to modulate the laser output. The result is feedback loop which forms a free-running oscillator. The frequency of oscillation is dependent on the time in which the laser signal travels to the target and returns, and therefore the distance to the target. The period of oscillation is measured with digital electronics, and the result calibrated and output by the on-board processor. Click for more info.


Acuity products of Schmitt Industries

2765 NW Nicolai Street

Portland, OR 97210


E-mail: sales@acuitylaser.com

Tel.: (503) 227-7908

Fax: (503) 223-1258

AR4000 laser distance sensor




Stress Distribution and Magnitude Measured by New System


Sensor Products Inc. introduces the Topaq® Advanced Imaging System. Used in conjunction with Fuji Prescale/Pressurex stress indicating films, Topaq provides a unique perspective of the distribution and actual magnitude of stress between any contacting or impacting surfaces. Unlike FEA, Topaq is a post-process interpretative system that actually collects stress and force data at the interface surface. In many instances, Topaq can be used to confirm the results of FEA analysis. Topaq has extremely rapid response time usually requiring no more than five seconds to render an image. In general, any application involving stress between two objects could benefit from Topaq's capabilities. Measuring pressure distribution and magnitude in components, tools and machines as well as determining effective placement of strain gauges and drawing pressure in dies are some of the common applications using Topaq.. Electronics packaging applications, heat sinks and PCBs lend themselves particularly well to interpretation with this unique system.


Gerard E. Mayers 

Sensor Products Inc.

188 Route 10 West, Suite 307,

East Hanover, NJ 07936-2108 USA

Phone: (+1) 973.560.4826



TOPAQ screen-capture



 New Range of non Contact Rotary Torque Transducers


Sensor Technology has introduced their new range of TORQSENSE RWT Rotary Torque Transducers. With full-scale ranges between 100 mNm and 10,000 Nm, the E300 RWT1 series of transducers utilizes the little known Surface Acoustic Wave (SAW) phenomenon. This SAW approach has allowed the development of small transducers, which are not only exceptionally accurate, but more importantly, require no physical contact between the revolving shaft and its housing. In a TORQSENSE transducer, the surface waves are produced by passing an alternating voltage across the terminals of two interleaved comb-shaped arrays that are laid onto one end of piezoelectric substrate. A similar ‘receiving’ array, at the other end of the substrate, converts the wave back in to an electric signal. self contained data display and recording system.


PO Box 36, Banbury,

Oxon, England OX15 6JB

Phone: +44 (0)1295 730746

Fax: +44 (0)1295 738966

Email: info@sensors.co.uk


Rotary Torque Transducers


2048 x 1 Linear Image Sensor


Pixel Devices Intl., Inc. of Sunnyvale, CA is pleased to announce that we are now shipping sample quantities of our new Low Noise Linear (LNL) 12 bit image sensors. These sensors, which contain 2048 pixels, are designed for users who need high speed and very low noise at room temperature. The LNL2048R pixel size is 200 micron by 7 micron and is designed for the spectrographic market. The LNL2048S has 7 micron by 7 micron pixels and is designed for high resolution low light level imaging. Both sensors are designed to produce 12 bits/pixel and, depending on the imaging mode, can produce higher bit depths. The LNL sensors can operate in four modes: Read On Integration (ROI), Read After Integration (RAI), Single Read During Integration (SRDI) and Multiple Read During Integration (MRDI). These modes are made possible by our Pixel Level Processing (PLP) and the differential output channels at each pixel. Additionally, each pixel can be individually set to operate in either a low gain or high gain state.


Gary Glaser

408-616-8852 x 156

E-mail: glaser@pixeldevices.com



First Oxygen Sensor for Aggressive Chemical Media


Sensor is applied especially in process engineering. It can be used interalia for direct in-line measurements, even in highly aggressive media e.g. hot acids or aggressive gases. But also in the food industry, SentrOxy®-Spec is well suited for measuring of oxygen in viscous media. In the following, we would like to give you a short summary on the different advantages of fibre-optic sensor systems of the SentrOxy®-Spec family: 

  • no oxygen consumption during measurement;

  • fibre-optic signal transmission, suitable for use in explosion risk areas;

  • direct in-line measurement possible, without bypass systems;

  • miniaturized sensors from 300 µm diameter;


Mr. Michael Baer, 

Phone: +49-351-871 86 50, 

E-mail: M.Baer@sentroxy.com




Process  Analyzer  Sample System Technology


Sherman’s companion volume, Process Analyzer Sample-Conditioning System Technology (Wiley-Interscience  1-800-CALL-WILEY), scheduled for publication in January 2002, is a 575+ page reference book on every aspect of sample system design and fabrication.  The 12 chapters cover components (probes, transfer lines, filters, coolers, pumps, separators, flow-pressure measurement and control), materials of construction, electrical hazards, climate controls and other matters.  In the final chapter, Sherman reviews thirteen case examples discussing systems & components that worked and why as well as those that didn’t and why.


Terrence K. McMahon

McMahon Technology Associates

135 Fort Lee Road, Leonia, NJ  07605

Tel: 201-585-2050, fax: 201-585-1968

E-mail: mcmahontec135@aol.com



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