944-133-5010

Attenuator.qxd 9/17/01 9:27 PM Page 1 Attenuators Attenuator.qxd 9/17/01 9:28 PM Page 2 Amphenol Fiber Optic Products attenuator product line consists of fixed and variable optical attenuators. An attenuator, by definition, is a device which precisely reduces an optical signal from point-to-point. The loss can be achieved through various technologies such as absorption, scattering, interference (thin film) filter, or air-gap. Amphenol has successfully developed three varieties of attenuators using select technologies to provide the best products in the market place. plug style (fixed) - absorption in-line (fixed) - scattering variable - air-gap Attenuator Family The most common use of the optical attenuator, whether fixed or variable, is in optical networks where erbium doped amplifiers are being used. Attenuators are used to adjust optical signal levels thereby increasing network flexibility and providing management of optical power. Table of Contents % of Power dB % of Power 0dB 100.00% 11dB 7.94% 1dB 79.43% 12dB 6.31% 2dB 63.10% 13dB 5.01% 3dB 50.12% 14dB 3.98% 4dB 39.81% 15dB 3.16% 5dB 31.62% 16dB 2.51% 6dB 25.12% 17dB 2.00% 7dB 19.95% 18dB 1.58% 7-8 8dB 15.85% 19dB 1.26% 9 9dB 12.59% 20dB 1.00% 10 10dB 10.00% Page # 1 Technology, Definitions, Testing 2 Plug Style Attenuators 3-4 Comparison Graphs 5 In-Line Attenuators 6 Terminators Polishing dB = 10 log (% transmission) dB Introduction Variable Attenuators Attenuation (dB) vs. Percent of Transmitted Power www.amphenol-fiberoptics.com sales@amphenol-fiberoptics.com Customer Service 800-944-6446 Attenuator.qxd 9/17/01 9:28 PM Page 3 Technology, Definitions and Testing Abr. Key Concept Units Desciption & Definition A Attenuation dB Loss of power from input A = 10 log (P1 / P0) ∆A Attenuation Tolerance dB The ∆ between the marked attenuation value on a device and the actual attenuation RL Reflectance, Return Loss dB Ratio of reflected power back to any port PDL Polarization Dependent Loss dB The maximum attenuation variation over all input polarization states Comparison Graphs Flatness over Wavelength Flatness over Temperature Attenuation vs. Temperature 10 dB, SC Plug Attenuator Attenuation vs. Wavelength 5 dB SC Plug Attenuator 5.6 10.5 Attenuation (dB) Attenuation (dB) 10.4 5.2 Plug Attenuator 5 4.8 10.1 10.0 1310 1360 1460 Wavelength (nm) 1510 1560 0 Attenuation vs. Wavelength 3 dB In-line Attenuator 2.5 1310 1360 1460 1510 Attenuation (dB) Attenuation (dB) In-line Attenuator 3 150 Attenuation vs. Temperature In-line Attenuator 1310 nm 1550 nm 4.4 4.2 4.0 3.8 -40 1560 Attenuation vs. Wavelength VOA set to 8.5 dB 10 -20 0 20 Temperature 40 (˚C) 60 80 Attenuation vs. Temperature VOA 10.0 9 Variable Attenuator 8.5 8 7.5 Attenuation (dB) 9.5 1310 nm 1550 nm 9.0 8.0 7.0 6.0 5.0 1310 1460 1360 Wavelength (nm) 1510 -20 1560 7 6 1460 1510 Attenuation (dB) Linear Variable Attenuator 8 1360 20 Temperature 40 60 (˚C) 10.0 9 1310 0 Attenuation vs. Temperature LVOA Attenuation vs. Wavelength LVOA set to 7.5 dB 10 5 1260 100 Time (hours) 4.6 3.5 7 1260 50 4.8 Wavelength (nm) Attenuation (dB) 10.2 4.4 1260 4 Attenuation (dB) 10.3 4.6 2 1260 1310 nm 1550 nm -40 ˚C to +70 ˚C 5.4 1310 nm 1550 nm 9.0 8.0 7.0 6.0 5.0 1560 -20 Wavelength (nm) 2 0 20 Temperature (˚C) 40 60 www.amphenol-fiberoptics.com sales@amphenol-fiberoptics.com Customer Service 800-944-6446 © 2001 Amphenol Corp. 9/01 Printed in U.S.A. Attenuator.qxd 9/17/01 9:28 PM Page 4 Plug Style Attenuator Amphenol’s Plug Style Attenuator is a fixed optical attenuator often referred to as a build-out or pad style attenuator. The plug attenuator is compact in size, offers attenuation values from 0-20dB and is available in industry standard connector styles FC and SC with either flat or angle polish. Optical attenuators have proven to be a critical component of any fiber optic network. By introducing an attenuator, you are able to adjust the transmission signal into the dynamic range of the receiver. This increases the life span of more expensive optical equipment and ultimately provides a clearer transmission signal. With a flat attenuation over temperature and the operating bandpass, Amphenol’s 944 and 954 series plug attenuators are proven cost savers and perfectly suited for traditional telecommunications, CATV and private network applications. Common Specifications Attenuation Values: < 5 dB + 0.5 dB > 6 dB + 10% of nominal value Back Reflection/Return Loss Amphenol’s plug style attenuators use light absorption technology as opposed to scattering. This eliminates the scattering of light into the fiber cladding that could be reflected back from the connector interface. With the short distance from connector end-face to end-face, the reflected light creates interferences that in turn create insertion loss variation as the wavelength changes. The light absorption technology has proven to be the superior technology for this compact design. Super polish: