Brewster windows are optical components designed to achieve specific optical effects and have important applications especially in laser and optical waveguide systems.
It is mainly based on the principle of Brewster’s angle, which is the phenomenon that incident light can completely eliminate reflected light when it passes through optical materials at a specific angle.
When light is incident on the surface of the window at Brewster’s angle (that is, approximately 56.3 degrees), the polarization state of the reflected light is completely perpendicular to the incident light.
This causes the light transmitted through the window to be fully polarized. When unpolarized light is incident on the window at Brewster’s angle, the reflected light retains its polarization properties, while the transmitted light passes through the window in a fully polarized form.
This property makes Brewster windows very useful in applications requiring polarized light.
Brewster windows utilize the characteristics of the Brewster angle to effectively improve the performance of a variety of optical systems, especially in applications that require high efficiency and high-quality polarized light, playing an important role.
The design of Brewster windows requires very precise determination of the Brewster angle, which depends on the refractive index of the window material.
Commonly used materials include quartz, sapphire, etc.
Specification
| Materials | quartz, sapphire |
| Wavefront Distortion | λ/4@633nm |
| Diameter Tolerance | ±0.2mm |
| Smoothness | 40/20-20/10 |
| Thickness Tolerance | ±0.2mm |
| Clear Aperture | >90% |
| Bevel | <0.2-0.5mm*45° |
| Parallelism | <3′ |
| Coating | Customized |
| Transmittance range | / |