We offer right angle, triangular, roof, penta, dove, 30°-60°, wedge and dispersion prisms as well as corner cubes. Our optical prisms can be coated with standard and custom anti-reflection (AR) coatings as well as reflective metallic or dielectric coatings or polarizing coatings.
Our range of optical prisms is available made from various materials, ranging from BK7 and quartz glass like Fused Silica to crystals like Ge, CaF2, BaF2, ZnSe, etc.
Precision optics of this kind, manufactured and coated to very specific and demanding tolerances, is in great demand by our customers. Other available components that can be realized include optical windows, optical mirrors, spherical lenses and molded glass aspheric lenses, cylindrical lenses or optical filters. All featuring high precision, smallest tolerances (dimensional and angular) and special coatings for exotic wavelengths, even into the UV spectral range.
Additionally, we carry a broad range of complementary products such as rotary and translation stages, optical tables, breadboards and platforms, etalons, optical scanners and deflectors as well as a broad range of optical test and measurement equipment.
Optical prisms consist of material that is optically transparent to light of the relevant wavelength. This material is shaped (usually by grinding and polishing) into a geometric form in which the end faces are not parallel to each other. This results in optical refraction when a light beam is sent through the optical prism. Typical applications for optical prisms are dispersion, reflection, deflection, rotation and axis offset of a light beam.
How to Select Your Optical Prism
Dispersive prisms take advantage of the fact that the degree of refraction or deflection of the light beam in the prism depends not only on the refractive index of the material, but also differs with the wavelength of the light due to the chromatic dispersion of the material. This allows different wavelength components of a beam to be separated or, in the opposite direction, beams of different wavelengths to be combined into one beam.
In addition to optical refraction, reflection at one or more interfaces of a prism is often used. In reflective prisms, either some of the surfaces are coated with reflective materials like metals, or the angle of incidence of the beam is such that total internal reflection at the interface or interfaces can be used. Prisms showing multiple internal reflections such as rectangular or pentaprisms are often used for image rotation in imaging systems.
Right Angle Prisms:
Depending on which of the surfaces of a rectangular prism the light is incident through, such a prism can deflect a light beam by 90° or 180°. If the light beam enters through one of the two legs of the right-angled prism, total internal reflection at the hypotenuse surface occurs, and the beam exits at the other leg of the prism deflected by 90°. This makes a right-angled prism used in this way an alternative to an optical mirror.
When the light beam is incident through the hypotenuse surface, on the other hand, the light is totally internally reflected at each of the two legs of the rectangular prism and emerges – deflected by 180° – in a direction parallel to the incident beam. Often a single prism can replace multiple mirror setups, with the added advantages of reduced size, lower possible misalignment and thus easier alignment and higher accuracy.
If you remove the triangular "top" from a rectangular prism, the result is a Dove prism with two side faces that are perpendicular to each other but do not form a common edge. Due to its reduced size, a Dove prism can be used as a reflective prism in applications with limited installation space. In this case, the light enters the longest surface of the prism, is totally reflected at each of the two side surfaces and exits parallel to the input beam. The more common application of Dove prisms, however, is image rotation. Here, the light passes through the prism along the longitudinal axis and is reflected once at the bottom surface and inverted. If the prism is now rotated around its longitudinal axis, the image is rotated by twice the value of rotation. For example, a rotation of the prism by 10 degrees leads to a rotation of the image by 20 degrees.
Roof prisms are used for a right-angle deflection of a light beam, with total internal reflection at the hypotenuse of the prism. After passing through a roof prism, the image is both laterally inverted and upside down.
A penta prism deflects a beam of light or an image by exactly 90°, without inversion or reversion. The resulting image after passing through a penta prism is therefore neither laterally inverted nor upside down. Furthermore, the 90° deflection angle does not depend on an exact alignment of the prism relative to the beam. Again, a single penta prism can replace two single mirrors with greater stability and less potential for optical error.
Wedge-shaped prisms feature a slight deviation in the parallelism of the top and bottom surfaces in the range of a few arc seconds to a few degrees. Wedge prisms are mainly used for directional changes of laser beams. In many applications, wedged windows from our product portfolio can be used as an alternative to wedge prisms.