HP HP-Bench-Briefs-1993-01-03 free download

File name HP-Bench-Briefs-1993-01-03.pdf

I I I I SERVICE INFORMATION FROM HEWLETT-PACKARD I I 1st Quarter 1993 I i ! The Optical Spectrum Analyzer I I Richard OgglHewlett-Packard In reality, prisms are too inefficient. microwave spectrum analyzer. The To reduce the space required by a result is the ability to measure prism, a grating is used. The effect of baseband modulation information on the grating is the same as the prism, the optical signal, but without any in- except the spreading happens much formation about the wavelength of faster and the light is now reflected the optical signal. in the other direction. The variable slit and photodetector are still used. OSA Wavelength Measurements Introduction The Lightwave Signal Analyzer Again, the OSA is used to show The optical spectrum analyzer (or The lightwave signal analyzers intro- power levels as a function of I OSA) is a very common piece of test duced several years ago are based on wavelength. (This is just like micro- i equipment on the lightwave bench. a broad-band photodetector used to wave spectrum analyzers, which These instruments were first intro- demodulate an optical signal. The show power versus frequency.) Recall ! duced about 10 years ago. HP's basic output of the photodetector is that frequency and wavelength are in- OSA product is the HP 71450A, which coupled to a preamplifier. This verse relations. The OSA sweeps in- operates in the 600 to 1700 nm range. amplified signal is then routed to a creasing wavelength, which is de- Standard hardware options include (See "Optical Spect