Semi Pentagonal Prism

The  Semi-Pentagonal Prism produced by Ultraopto Optoelectronic Technology Co., Ltd. can deflect light by 45° without flipping or rotating it. The reflective surface is coated with an aluminum-coated black paint protection or a medium high reflection film to increase the transmittance. 

Semi-pentagonal prisms are combined with Schmitt prisms of the appropriate size for Behan prism pairs. The Beehan prism pairs will flip and rotate the image without deflecting the light. 

Ultraopto Optoelectronic Technology Co., Ltd. can stably accept custom semi-pentaprisms of various specifications for a long time. By precisely controlling the polishing, coating and bonding processes,  Ultraopto Optoelectronics can stably provide such products with high beam offset and high resolution.

Light deflection of 45° or 48°, etc

High transmittance

High resolution

Anti-reflective coating +AL film/black protective paint

Or coated with an anti-reflective film + dielectric high reflection film

Ultraopto’s Semi-Pentagonal Prism is a high-precision optical component specialized in 45° light beam deflection and upright image transmission, serving as a core part in SLR camera viewfinders, optical measurement instruments and laser beam adjustment systems. Engineered with an optimized semi-pentagonal structural design, our Semi-Pentagonal Prism can accurately deflect incident light by 45° while realizing dextrorotatory upright imaging, eliminating the need for additional optical correction components and simplifying the structural design of optical systems, which is essential for optical devices that require real-time upright image observation and precise light path control. Crafted from premium BK7 grade A optical glass and high-purity fused silica, our Semi-Pentagonal Prism is manufactured with ultra-precise grinding and polishing processes, implementing strict angular and dimensional tolerance control, with superior surface flatness of λ/2 @632.8nm and a surface quality rating of 60-40 scratch and dig, ensuring low optical loss and high-fidelity light and image transmission for precision optical systems.

Our Semi-Pentagonal Prism features excellent optical stability with consistent 45° light deflection performance regardless of minor changes in the incident light angle, ensuring reliable optical performance in complex working environments and avoiding image distortion or light path offset caused by slight device vibration or installation deviation. The product is coated with multi-layer anti-reflection coatings on the incident and emergent surfaces, with an average reflectivity of less than 0.5% in the visible light band (630~680nm), and enhanced aluminum coatings with black paint on the reflection surfaces, with an average reflectivity of over 85% @630~680nm, further reducing surface reflection loss and improving light transmittance and image clarity. With a compact and robust structural design, our Semi-Pentagonal Prism exhibits excellent mechanical strength and environmental adaptability, resistant to temperature changes and mechanical vibration, and suitable for long-term stable use in both indoor precision optical instruments and outdoor industrial measurement equipment. We also offer customizable chamfer designs (<0.5mm×45°) and coating processes for specific spectral ranges, tailoring the product to the unique application requirements of UV, visible and infrared optical systems.

Ultraopto’s high-precision Semi-Pentagonal Prisms are widely applied in a diverse range of professional optical fields that demand 45° light deflection and upright imaging, including photography and videography where they serve as the core component of SLR camera viewfinders, deflecting the light captured by the lens by 45° and enabling photographers to see an upright and non-inverted image through the viewfinder for real-time shooting adjustment. They are also essential in optical measurement instruments such as theodolites and laser rangefinders, accurately controlling the optical path to ensure the accuracy of measurement results, and in laser systems for adjusting the direction of laser beams and ensuring the laser accurately illuminates the target position for laser processing and laser alignment. In optical laboratories, our Semi-Pentagonal Prisms are often used in complex optical path design to help researchers realize precise light beam control and optical experiments, and in industrial machine vision systems for light path adjustment and image transmission, providing clear upright images for surface defect detection and dimensional measurement of industrial products. Additionally, they are applied in pecan mirror assemblies and various custom optical systems for precise 45° light deflection and image transmission, meeting the diverse optical path design requirements of modern optical technology.

As a professional manufacturer of precision pentagonal prisms, Ultraopto offers fully customized Semi-Pentagonal Prism solutions to meet your unique optical system requirements. Our experienced engineering team can provide personalized customization of external dimensions, angular tolerance and surface quality, with strict control over light deflection accuracy and image transmission performance to match the specific design needs of your optical devices. We also support custom material selection and coating solutions, including premium optical glass and fused silica for different spectral ranges and environmental conditions, and wavelength-specific anti-reflection and high-reflection coatings to enhance optical performance and reduce light loss. 

All custom Semi-Pentagonal Prism orders undergo multi-stage strict optical performance testing and quality inspection, including light deflection accuracy detection, image clarity testing and coating performance verification, with a detailed quality inspection report provided to ensure the final product fully complies with your design specifications and application requirements. Backed by advanced optical prism processing technology and a complete quality control system, Ultraopto ensures stable batch supply capacity and consistent product quality, providing global customers with high-quality Semi-Pentagonal Prism products and comprehensive optical solutions. For more detailed technical parameters, product quotation information or custom design solutions for our Ultraopto Semi-Pentagonal Prism, please contact our professional sales and technical team through the official website, and we will provide you with efficient, professional and personalized optical solutions to support the development and production of your precision optical systems and devices.