Product principle and application of pentaprism

Pentaprism, as a key component in the optical field, is widely used in photography, measurement and scientific research due to its unique reflection principle and precise structure. Its core principle is to deflect the incident light by 90° through two accurate reflections, while maintaining the orientation and handedness of the image, avoiding the image inversion problem caused by ordinary right Angle prisms. Among the five reflecting surfaces inside the pentaprism, two key surfaces are coated with high-reflectivity silver film, and the remaining surfaces are reduced by anti-reflective coating to ensure efficient transmission of light.

In a SLR camera, the pentaprism is the core component of the optical viewfinder. The inverted image captured by the lens is reflected to the pentapraxis through the reflector, and corrected to the forward image through two reflections, so that the photographer can observe the real scene in real time, and accurately adjust the composition and focus. Compared to the lower cost five-sided mirror, the pentaprism significantly improves the brightness and stability of the shooting due to its total reflection characteristics, which has become the iconic design of professional cameras.

In addition, pentaprisms also play an important role in industrial calibration and building surveying. For example, the double pentaprism system combined with the plumb line can accurately calibrate the right Angle and the incidence Angle to ensure the construction accuracy. The scientific research field uses its high-precision optical path control ability to assist spectral analysis and optical instrument design.

Whether it is a photographer pursuing the ultimate image, or an engineer needing accurate measurement, pentaprism with its reliable optical performance and wide applicability, is the ideal choice for upgrading technology in many fields. In the future, with the progress of coating technology and material science, pentaprism will show its irreplaceable value in more cutting-edge scenes.