Do you think there is a natural beam splitter in nature?

The most common shape is a cube, consisting of two triangular glass prisms, which are bonded to the substrate with polyester, epoxy resin or polyurethane adhesive. Adjust the thickness of the resin layer so that half (a certain wavelength) of the light incident through a "port" (that is, the face of a cube) is reflected, while the other half is continuously transmitted due to total internal reflection. Polarization beam splitters, such as Wollaston prisms, use birefringent materials to split light into beams with different polarizations. Another design is to use a half-silvered mirror, a piece of glass or plastic, and a transparent thin metal coating. Now aluminum is generally deposited by aluminum vapor. The thickness of the deposit is controlled so that a part (usually half) of the light incident at an angle of 45 degrees and not absorbed by the coating is transmitted and the rest is reflected. A very thin half-silvered mirror used for photography is usually called a protective film mirror. In order to reduce the light loss caused by the absorption of the reflective coating, a so-called "Swiss cheese" beam splitter is used. Initially, these were perforated highly polished metal sheets to obtain the required reflectivity and transmittance. After that, metal is splashed on the glass to form a discontinuous coating, or a small area of continuous coating is removed by chemical or mechanical action, resulting in a very real "semi-silvered" surface. Dichroic optical coatings can be used instead of metal coatings. According to its characteristics, the ratio of reflection to transmission will change as a function of the wavelength of incident light. Beam splitters are used in some elliptical reflection spotlights to disperse unwanted infrared (thermal) radiation and output couplers in laser structures.

A third kind of beam splitter is a dichroic prism assembly, which uses dichroic optical coatings to split an incident beam into a plurality of output beams with different spectra. This equipment is used for three-tube color TV cameras and three-color film cameras. Currently used in modern three CCD cameras. An optically similar system is used in reverse as a beam combiner in a three-LCD projector, in which light from three independent monochrome LCD displays is combined into a single full-color image for projection. The beam splitter of single-mode fiber used in PON network uses single-mode behavior to split beams. The beam splitter "splices" two optical fibers into an X. The arrangement of mirrors or prisms that use a lens and an exposure point to shoot stereoscopic images is sometimes called a "beam splitter", but this is a misnomer because they are actually a pair of periscopes, and the reflected light no longer coincides. In some very rare stereo photography accessories, mirrors or prism blocks are similar to beam splitters. Overlapping themes with different angles can directly generate embossed 3 d images through color filters, or record sequential 3D videos through rapidly alternating shutters.