Custom Porro Prisms

Porro prisms are precision optical prisms widely used in binoculars, periscopes, telescopes and optical imaging systems. A Porro prism system can fold the optical path, invert the image and increase the distance between the objective lenses and eyepieces, helping optical instruments achieve a wider stereoscopic effect and compact structure.

Realpoo Optics manufactures custom Porro prisms according to customer drawings, samples and optical design requirements. We support different materials, dimensions, coatings, surface accuracy levels and angle tolerances for OEM optical instruments.

What Is a Porro Prism?

A Porro prism is a type of reflecting prism used to change image orientation and fold the optical path. In many optical instruments, two Porro prisms are used together as a Porro prism pair to invert and reverse the image, allowing the viewer to see a correctly oriented image.

Porro prisms are especially common in traditional binoculars because they provide good image quality, high light transmission and strong depth perception.

Key Features

• Used for image erection and optical path folding
• Commonly used as Porro prism pairs
• Suitable for binoculars, telescopes and periscopes
• Provides good stereoscopic imaging performance
• Available in BK7, BAK4, fused silica and custom optical glass
• AR coating and reflective coating available
• Custom size, tolerance and coating available
• Suitable for OEM optical instrument manufacturing

Porro Prism Applications

Porro prisms are widely used in:

• Binoculars
• Telescopes
• Periscopes
• Rangefinders
• Observation instruments
• Imaging systems
• Optical measuring devices
• Military and defense optical systems
• Scientific optical instruments
• Custom optical assemblies

Material Options

Realpoo Optics can manufacture Porro prisms using different optical materials according to system requirements.

Common materials include:

• N-BK7
• H-K9L
• BAK4
• Fused Silica
• Sapphire
• Other optical glass materials upon request

BK7 and H-K9L are commonly used for general visible optical systems. BAK4 is often selected for high-quality binocular prism systems because of its optical performance. Fused silica is suitable for UV, high-power laser or applications requiring better thermal stability.

Technical Specifications

Coating Options

Coating is important for improving transmission, reducing reflection loss and enhancing image brightness. Realpoo Optics can provide custom coating solutions according to wavelength range, optical structure and application requirements.

Available coating options include:

• MgF2 coating
• VIS AR coating
• Broadband AR coating
• High reflective coating
• Aluminum coating
• Silver coating
• Protected metal coating
• Blackened edge treatment

For binocular and imaging systems, AR coating is commonly applied to entrance and exit surfaces to improve image brightness and contrast.

Porro Prism vs Roof Prism

Porro prisms and roof prisms are both used for image correction and optical path folding, but they are used in different optical structures.

Porro prisms usually provide a wider optical layout and stronger stereoscopic effect, which is why they are commonly used in traditional binoculars. Roof prisms allow a more compact and straight optical design, making them suitable for slim binoculars and compact observation instruments.

For OEM optical design, the choice between Porro prism and roof prism depends on size, image quality, optical path, cost and mechanical structure.

Custom Manufacturing Capability

Realpoo Optics supports custom Porro prism manufacturing for optical instrument manufacturers. We can provide prototype samples, small batch production and mass production according to customer requirements.

Our custom capabilities include:

• Custom prism dimensions
• Custom optical glass material
• Custom angle tolerance
• Custom surface quality
• Custom AR or reflective coating
• Custom blackened edge treatment
• Porro prism pair matching
• OEM optical assembly support

Quality Control

Each Porro prism can be inspected according to customer specifications. Inspection items may include dimension, angle tolerance, surface quality, surface accuracy, coating performance and appearance quality.

For imaging applications, surface quality, coating uniformity and prism pair matching are important for achieving stable image performance.

Information Needed for Quotation

To provide an accurate quotation, please send us the following information:

• Prism drawing or sample photo
• Material requirement
• Size and tolerance
• Surface quality
• Surface accuracy
• Angle tolerance
• Coating requirement
• Quantity
• Application details

Request a Custom Porro Prism Quote

If you need Porro prisms for binoculars, periscopes, imaging systems or custom optical instruments, please send us your drawing and technical requirements. Realpoo Optics can provide custom Porro prism manufacturing solutions for OEM optical applications.