Optical coatings for beamsplitters have several different dimensions. The popular coatings for optical coatings are stated here below. Continue reading to know.
Hybrid partial-reflection coatings
Hybrid, metal-dielectric coatings are combination of all benefits of metals and dielectrics and with little polarization sensitivity, the coatings create a moderate-absorption beamsplitter. Generally, the absorption is about 10% and the transmission and reflection are approximately 45 percent. The s-and p-polarized components generally remain within 10% with each other. The best part is the spectral flatness which makes these beamsplitters most suitable for wavelength scanning instruments.
Partial-reflection coatings is for a high-level efficiency. The negligible absorption in the coatings along with the transmitted and reflected components have the same intensity over the wavelength range with an average of p- and s-polarizations. These coatings are too sensitive to polarization with s- and p-components which differs from 70%. Considering the polarization implications for the optical system’s integration, care should be taken while using these optical beamsplitters.
All-dielectric Nonpolarized Coatings
This is one type of cube beamsplitter coating which is designed for those applications where polarization effects should be minimum. This is not like the hybrid coatings, as these dielectric coatings are for specific wavelengths with high performance. This is where they can surpass the performance of any other cube beamsplitters.
With a high-tensile-strength of elastic membrane a pellicle beamsplitter is made. It is expanded like a drum-head over an anodized black flat metal frame and attached to the lapped edge of the frame. The membrane has a very less thickness, so that the difference of the primary and ghost images becomes hardly recognizable.
Hopefully this blog has helped you understand the variations available for beamsplitter coatings. The usages of this particular thing are very specific and the technology is quite complex. If you have any query, you can share you view with us.