Wavelength Meter Module
Wavelength meter is also called Wavemeter, which uses beam interference to precisely measure wave-length of laser beams. Wavemeter is not a new kind of instrument. Commercially, there are two variants of scanning wavemeters and static devices with no moving parts.
The scanning wavemeter is based on Michelson interferometer, in which one arm can change its length, leading to Fourier transform spectroscopy. In such a kind of wavemeter, light travels in free space. Water absorption in E-band wavelength range will prevent the wavemeter from determining correct wavelength. Further, to drive the motion of one interference arm, the mechanical wear-out will degrade the precision of repeated wavelength measurements.
The static wavemeter with no moving parts is based on static Fizeau interferometer, which consists of two plane reflecting surfaces with a slight deviation from exact parallelity. With the laser illumination, the fringe pattern of the interferometer, whose period depends on the wavelength, is sampled by a photodiode
- High speed
- High wavelength accuracy and repeatability
- No moving parts
- Integration flexibility
- No water absorption in E-band
- Wavelength measurements
- DWDM systems
- Research laboratories
1) In full wavelength range from 1250 to 1650 nm
2) Within ± 200 pm.