Newport Spectra-Physics Newsletter - #31 - November 2009 - (Page 21)

w w w. n e w p o r t . c o m November 2009 Page 21 80 MHz Balanced Photoreceivers These meticulous 80 MHz balanced photoreceivers make all the difference when you need to see a small signal. Key Features 25 dB common-mode rejection ratio lets you see your signal High gain and linearity Visible and near-IR versions The New Focus™ 80 MHz balanced photoreceivers are ideal for coherent heterodyne-detection applications including doppler LIDAR, and optical coherence tomography. These 80 MHz balanced photoreceivers can make the difference when you need to see a small signal. Just like our other balanced photoreceivers, the Model 18X7 balanced photoreceivers work by subtracting the photocurrent from two well matched photodetectors. Common-mode noise that is present on both the reference and signal beams (such as laser intensity noise) is canceled out and doesn’t appear as part of the signal. Any imbalance between the photocurrents generated by the reference and signal photodetectors, whether intentional or unintentional, is amplified and is seen as the signal. These Model 18X7 photoreceivers contain the same photodetectors as those in our Model 18X1 series photoreceivers, and provide higher gain than their wider-bandwidth 650 MHz and 800 MHz balanced photoreceiver counterparts. Both free-space (FS) and FC-connectorized versions are available. To ensure safe operation, we strongly recommend our Model 0901 power supply. WEB See our website for more info. Please click here. Nirvana™ 125 kHz Auto-Balanced Photoreceivers These new auto-balanced photoreceivers enable even the smallest signals easy to see. Key Features Patented auto-balancing circuit reduces noise by 50 dB so you can see your signal Maintains automatic DC balance between reference and signal arms Ideal for spectroscopy D E T E C T O R S The New Focus ™ Models 2007 and 2017 auto-balanced photoreceivers can cut the effects of laser noise by 50 dB, making even very small signals easy to see. In spectroscopy, ellipsometry, or heterodyne-detection experiments, these photoreceivers can yield shot-noise-limited performance without the need for lock-in amplifiers or high-frequency modulation. The patented auto-balancing circuit uses a low frequency feedback loop to maintain automatic DC balance between signal and reference arms. In effect, the circuit behaves as a variable-gain beamsplitter. This, in conjunction with the subtraction node, cancels common-mode laser noise with greater than 50 dB rejection at frequencies less than 125 kHz. With the Nirvana photoreceiver, you won’t have to operate in the RF regime to avoid unwanted laser noise. And you can adjust the loop bandwidth for your particular application. WEB See our website for more info. Please click here. Family of Brands — Corion® • New Focus™ • Oriel® Instruments • Richardson Gratings™ • Spectra-Physics® http://www.newport.com http://www.newfocus.com/products/?navid=3&theView=modelGroupDetail&productLineId=3&productGroupId=142&modelGroupId=1202 http://www.newfocus.com/products/?navid=3&theView=modelGroupDetail&productLineId=3&productGroupId=142&modelGroupId=1202 http://www.newfocus.com/products/?navid=3&theView=modelGroupDetail&productLineId=3&productGroupId=142&modelGroupId=1056 http://www.newfocus.com/products/?navid=3&theView=modelGroupDetail&productLineId=3&productGroupId=142&modelGroupId=1056

Table of Contents for the Digital Edition of Newport Spectra-Physics Newsletter - #31 - November 2009