Definition of Amici Roof Prism
The best prism for binoculars is generally considered to be the roof prism. The Amici Roof Prism, also known as a Dachkanten Prism or Dach Prism, is a specially designed optical element used to deflect light by 90 degrees while inverting the image. Unlike a standard right angle prism, the Amici Roof Prism has an additional triangular “roof” section on its longest side. This roof shape ensures that the light undergoes total internal reflection (TIR), effectively flipping the image horizontally.
Non-Dispersive Amici Roof Prism
Non-dispersive Amici Roof Prisms are often used in optical devices where the direction and orientation of an image need to be maintained. These prisms are most commonly found in telescopes, binoculars, spotting scopes, endoscopes, and profile projectors where they help to orient the image, turning it right side up and bending it 90 degrees. When it is necessary to correct and redirect inverted images from other optical elements, the Amici Roof Prism provides a solution, making it a versatile component in many optical systems.
Dispersive Amici Prisms
In contrast to non-dispersive Amici prisms, dispersive Amici prisms are made by joining two triangular prisms – typically, one made of crown glass (lower dispersion) and the other made of flint glass (higher dispersion). This configuration causes the prisms to separate light according to its wavelength, creating a dispersive effect. Light enters the first prism, is refracted, and then refracted again at the interface between the two prisms, leaving it almost parallel to the incident beam but offset. Dispersive Amici prisms are commonly used in spectrometers and handheld spectrometers, and are designed to ensure that a specific wavelength (usually the central wavelength) leaves the prism parallel to the incident light, albeit slightly offset.
Manufacturing and Precision
Manufacturing Amici roof prisms requires high precision, especially the roof angle. Even the slightest deviation (as little as four arc seconds from a perfect 90-degree angle) can cause optical defects such as ghosting. To ensure excellent optical performance, the roof angle of the prism must be accurate to within a few arc minutes.
At Mok Optics, we specialize in making both dispersive and non-dispersive Amici roof prisms to precise specifications. Our prisms are typically made from high-quality borosilicate crown glass, but other materials are available upon request. Thanks to our advanced mechanical and metrology systems, we can guarantee that our prisms meet the highest standards with a surface quality of 60-40 scratches and dents. The roof angles of our Amici prisms are guaranteed to be accurate to within 3 arc minutes, ensuring the best performance for our customers.
Applications in Optical Instruments
Amici roof prisms are essential components in many optical instruments, where they serve both a functional and corrective role. For example, in telescopes and binoculars, they help convert inverted images to the correct orientation, which is essential for accurately viewing objects. In devices such as endoscopes and profile projectors, they allow the optical path to be manipulated while maintaining image quality and orientation. When integrated with other optical components, Amici prisms offer a versatile solution for manipulating light and ensuring images are sharp and accurate.
Summary
At Mok Optics, we pride ourselves on being able to customize our Amici roof prisms to our customers’ specific needs, ensuring precision and durability in every prism we produce. Whether for general optical use or specialized applications such as spectroscopy, our high-quality prisms meet the exacting standards of the most advanced optical systems.