摘要 |
The invention relates to wavelength-selective and tunable optical filters for transmitting the light in a narrow optical spectral band, centered around an adjustable wavelength, and for blocking the transmission of wavelengths lying outside of this band. In a micromachined monolithic structure containing the optical filter proper, the component comprises a low-absorption light detection element used for slaving the tuning control of the filter to a wavelength received by the filter, this element transmitting the majority of the radiation at this wavelength. The filter is a Fabry-Pérot interferometric filter, the cavity (C) of which is tuned to a value that maximizes the power detected by the light detection element. The filter is preferably based on layers of indium phosphide and air gaps. The detection element preferably comprises a layer of gallium-indium arsenide 74 suitable for detection of the intended wavelength band.
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