The invention relates to the technical field of optical thin films, in particular to a low-phase-difference
metal reflecting mirror suitable for a
space environment and a preparation method and application of the low-phase-difference
metal reflecting mirror. The bonding layer, the
metal layer, the first protective layer, the first low-refractive-index layer, the high-refractive-index layer, the second low-refractive-index layer and the second protective layer are sequentially plated on the optical substrate; the optical substrate is made of
silicon; the bonding layer is made of
nickel-
chromium; the metal layer is made of silver; the first protective layer and the second protective layer are made of aluminum
oxide; the first low-refractive-index layer is made of
silicon dioxide, and the second low-refractive-index layer is made of
silicon dioxide; and the high
refractive index layer is made of
niobium pentoxide.
High reflectivity in a
broadband range is realized through the metal layer,
phase difference regulation and control design is performed by using an asymmetric equivalent layer theory in an
optical thin film design method,
phase difference regulation and control of a communication waveband are realized, and adaptability and stability of an optical element under a
space environment condition are improved by using the outermost protective layer.