（Optical lens manufacturer）Optical lens is often used by us. Today, I'd like to talk about the prism blank of optical lens. Let's see how many kinds of prism blanks it is divided into!
1. Ridge prism
（Optical lens manufacturer）The ridge prism deflects or deflects the image by 90 degrees. In fact, the roof prism can be regarded as a right angle prism, and the inclined plane is replaced by a 90 degree total internal reflection ridge. The cleanliness and quality of the total internal reflection ridge surface are very important. Only the light perpendicular to the incident plane and the exit plane can be rotated by 90 degrees, and all other light rays produce different deflections in almost the same way as ordinary right angle prisms. Ridge prism is used when both 90 degree angular deflection and vertical imaging are required, such as in the viewfinder of some instruments.
2. Wedge prism
（Optical lens manufacturer）As a beam control element in optical system, wedge prism plays a role similar to rocking disk in machinery. A given small deviation is required for the apex angle of wedge prism.
3. Pentagonal prism
（Optical lens manufacturer）Pentagonal prism has two important characteristics. The first is that when the image is deflected 90 degrees, it is neither reversed nor reversed. No matter how the angle of light passing through the pentaprism is 90 degrees, the effective angle of light passing through the pentaprism is the same. Therefore, the deflection has nothing to do with the orientation of the prism, which makes pentagonal prism have a particularly important application when the prism orientation can not be accurately controlled. Pentagonal prism is generally used in optical tools, collimators, rangefinders, image detectors and other instruments.
