Right Angle Prism-recommended For Exclusive Laboratory Use
The conventional shape is that of a triangle and in cases some of the optical prisms the geometrical forms are not found
. In fact prisms can be made from any material provided it is transparent and match with the wavelength for which they are designed.
One can find such prisms which have more tolerance and can meet the demanding application needs. These prisms are recommended for specialized laboratory use and for thermally sensitive applications the fused silica prisms are advised.
Some prisms are found to be suitable for beam bending and retroreflection applications.
These types of prisms are used in place of mirrors where distorted images become a problem and the prisms feature 100% reflectivity over an extensive wavelength range. In fact the reflecting surface has to be coated with protected aluminum if the incidence angle is wide.
The above mentioned prisms are very effective with respect to total internal reflection and these prisms may be used as 90 degree reflector or 180 degree retroreflector .These Prisms are available in different sizes ranging from 3.20 mm to 50.8 mm with a selection of antireflection coating.
On the other hand it is noted that a set of three mutually perpendicular reflective surfaces when form corner of a cube that works as retroreflector and this particular application has to be found to be very effective with respect to wide range of optical system.
In case of Right angle prism the antireflection coating reduces the surface losses but yet advantageously does not affect total internal reflection. The particular shine of retroreflectors of the transparent sphere type is quite evident for example the sparkle of cats eye.
In case of Corner cube retroreflector the retroreflection takes place over a wide range of incident angles. This makes it so effectual with respect to precise alignment applications.
The easiest way to model such retroreflector to take the help of sequential retro-reflect surface because this surface reflects rays back precisely along the incident path. In this respect it needs a mention that such surface as mentioned has to be tilted as much as possible so that the reflected rays can be along the incident path.
Interference Filter is specialized optical filters that reflects one or more spectral bands and transmit other and at the same time the co-efficient of absorption is kept almost at zero. This type of a filter is formed multiple thin layers of dielectric elements.