Related Optical Terms and Definitions. For a complete list go to our
Terms and Definitions Page.
Amplified Spontaneous Emission Source (ASE)
ASE, a process where spontaneously emitted radiation (luminescence) is amplified. In lasers and particularly in high-gain erbium-doped amplifiers, amplified spontaneous emission is usually an unwanted effect. It tends to limit the gain achievable in a single stage of a fiber optic amplifier to the order of 40–50 dB.
In a transmission system, the ratio of the overload level to the noise level of the system, usually expressed in dB. Ratio of the highest to lowest detectable signal of a system, expressed in dB.
Optical Power is usually measured in "dBm", or decibels referenced to one miliwatt of power. while loss is a relative reading, optical power is an absolute measurement, referenced to standards. You measure absolute power to test transmitters or receivers and relative power to test loss.
Relative Wavelength Accuracy
When randomly changing the wavelength and measuring the differences between the actual and displayed wavelengths, the relative wavelength accuracy is ± half the span between the maximum and the minimum value of all differences.
Wavelength is a term for the color of light, usually expressed in nanometers (nm) or microns (m). In Fiber Optics the wavelenghts mostly used are in the infrared region where the light is invisible to the human eye.