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DESIGN & PRODUCTS OPTOELECTRONICS though the signal processing for a sensing system of this type will be less cumbersome than that for a visible sensor, there is still the need to keep overall complexity down, in order to ensure that operational speed and signal to noise are both high, while cost and ease of implementation are both low. through technical collaboration between Melexis and hei- mann sensor Gmbh it has been possible to develop compact, cost-effective FIR sensor arrays that bring together the func- tional performance of high sensitivity thermopiles with sophis- ticated but streamlined signal processing. Each FIrray sensing device has multiple thermopile sensor elements and can be used to build up a simple map of the heat values over the target Fig. 2: Thermal profile of seat occupants. area in real time. Every thermopile within the array effectively has its own electronic amplifier and data converter. This avoids Conclusion the need to time multiplex the thermopiles’ signal and reduces With approximately 35,000 fatalities on the roads of Eu member considerably the signal noise. conversely it provides the neces- states each year, the importance of developing more effective sary performance without the need to specify a more expensive automotive safety systems cannot be underestimated. the microbolometer device. utilization of airbags has made a marked contribution to reduc- The array greatly simplifies the thermal imaging system it is ing the death toll, but there is still a need for this to be lowered integrated into by immediately capturing data from 64 pixels. further. As passive occupancy identification mechanisms are It has an adjustable frame rate that more than covers what is superseded by smarter systems which are better able to deter- needed for even the most high performance Ocs systems. ac- mine who or what is located in the passenger seat, the effec- curacy levels of ±1.5 °K are maintained when operating in the 0 tiveness of airbag deployment will be further improved and the °c to 50 °c range. By having its own devoted signal processing risk of harm ensuing thereby minimized. Through the develop- for each of its constituent sensing elements the noise issues ment of more advanced Ocs implementations based on opto- exhibited in visible systems can be circumvented. In addition, electronics, greater strides can be made in passenger safety. It interfacing is also much simpler to implement. use of a high is clear, however, that sensors operating in the visible spectrum speed I2c compatible digital serial interface and a triggered will tend to have their performance reduced by variations in light mode for synchronization with a control unit means these level and other irregularities. As FIR sensing techniques offer devices can, in additional to being used individually, be com- equal or better performance with far less costly data processing bined together to form an array with a larger imaging resolution than visible alternatives, they can see greater uptake from car if needed. manufacturers. Industrial laser system resistant to vibrations Super bright coloured LEDs delivered in and chemicals 1.0x0.5x0.35mm 0402 ChipLED packages the MIl-300rh (650nm red laser diode) and MIl-300- vishay Intertechnology has released a new series of super GH (532nm green laser diode) ruggedized industrial laser red, soft orange, yellow, yellow green, blue, and white ultra- systems from BEa lasers are well suited for metal-forming, bright LEDs in a tiny surface-mount 0402 ChipLED package measuring just 1.0x0.5x0.35mm. The VLMx1500-GS08 series de- vices provide exceptional bright- ness with a luminous intensity up to 180 mcd. While the blue and white LEDs in the VLMx1500-GS08 series use highly efficient InGaN technology, the super red, soft orange, yellow, and yellow green devices use the latest advanced allnGaP technology to increase light output by a factor of three. With their high brightness and small size, VLMx1500-GS08 series LEDS are suitable indicator and backlighting applications. the colour alignment, punch presses, welding, positioning, drilling, lEds are grouped by luminous intensity, wavelength, and targeting and many other heavy industrial applications. the forward voltage, they offer a wide viewing angle of 130°. The system includes a 12mm connector fitted to a black zinc white LEDs are chromaticity coordinated categorized accord- coated, stainless steel laser diode housing. the optics can ing to cIE 1931, per packing unit, with typical coordinates be standard round, line, cross (no additional charge), or a of 0.294 (x) and 0.286 (y) and a typical color temperature of target. It comes with a black Pvc coated 2-meter long cable 7,000 K. with a straight, or 90° connector and a 3.3 vdc switching VLMx1500-GS08 series LEDs are available in 8 mm tape. power supply. the units are liquid-resistant and built to with- rohs-compliant and vishay GrEEN, the devices are com- stand vibration, chemicals, impact and dust conditions, as patible with IR-reflow soldering processes and precondi- well as most other harsh environmental conditions. tioned according to JEdEc level 2a. BEA Lasers Vishay Intertechnology www.bealasers.com www.vishay.com 32 Electronic Engineering Times Europe September 2012 www.electronics-eetimes.com


EETE SEPTEMBER 2012
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