A beam splitting plate (or flat beam splitter) is a thin, flat glass substrate with specialized coatings:
Front surface: Coated with a dielectric beam-splitting film to split incoming light into reflected and transmitted components.
Back surface: Coated with an anti-reflection (AR) coating to minimize unwanted Fresnel reflections, ensuring high optical efficiency.
These plates are widely used in laser systems, interferometry, and imaging applications where precise light control is required.
Most beam splitting plates are designed for 45° incidence, offering several advantages:
Equal Power Splitting: At 45°, the reflected and transmitted beams often achieve near-equal intensity division (e.g., 50:50 split for non-polarizing plates).
Compact Optical Layouts: The 45° geometry simplifies integration into optical benches and systems, reducing space requirements.
Reduced Ghost Reflections: Properly angled coatings minimize stray light, enhancing signal clarity.
High Transmission/Efficiency: AR coatings on the back surface maximize light throughput.
Minimal Polarization Dependence: Non-polarizing designs maintain beam integrity for unpolarized light.
Durable Construction: Glass substrates provide stability under varying environmental conditions.
Laser Systems: Dividing laser beams for alignment or dual-path experiments.
Interferometry: Creating reference and measurement beams for precision measurements.
Imaging & Photography: Polarizing or non-polarizing plates for glare reduction or special effects.
Optical Communication: Signal routing in fiber-optic networks.
