I have tried to split the 1064 laser light into two equal energy spots by using a wedge prism of wedge angle 2 degree. But I cannot split the laser light. There are so many papers reported the splitting using wedge prism. Any other optics required for this? Kindly respond.
You see that there are two ways of beam splitting: both splitting beams have been produced in reflection geometry. In the case of a wedge prism both beams have equal intensity that dependent from incident angles and divergence angle equal to doubled wedge angle; second way of splitting, when You will use reflection/transmission geometry and try to find needed incident and azimuth angles to reach equal intensity transmitted and one of reflected beams. Look through well known Fresnel dependencies for light reflection as function of incident angle and polarization. Good luck!
If the beam is incident on the surface of the prism at the Brewster angle of incidence, then you can separate the s- and p-polarization from the beam (p-pol will be transmitted). Separating the beam into two equal energy spots will then depend on the polarization state of the laser beam; if it has a linear polarization, you can adjust its beam to 45° vs incidence plane. Just an idea.
There are many things that may be done. However, I believe what you are saying is that you have seen many papers referring to splitting a beam with a 2 degree wedge and you don't understand what they mean. Here is what they usually mean.
The wedge is not important for the splitting and is not what is doing the splitting. The splitting happens at one surface. One beam reflects and the other transmits. How this surface splits the beam is usually determined by a multi-layer optical coating and the angle of incidence. If you have an uncoated wedge, the reflected beam will be determined by the Fresnel coefficients. You can get different degrees of polarization in the reflection depending on the angle of incidence, etc. Optical coatings, on the other hand are usually specifically designed to produce a specific relation between the transmitted and reflected beam (intensity and polarization) at a specific incidence angle and wavelength. Many relations of intensity, polarization, and angle of incidence can be achieved, although some may be difficult (like reflecting P polarization and transmitting S)
So what the heck does the 2 degree wedge have to do with anything?!?! The wedge prism is used to prevent the second surface reflection (or multiple reflections) from confusing the beams. With a 2 degree wedge the reflection from the second surface will be 4 degrees away from the reflection of the first surface and is easily discarded at a subsequent aperture. Normally the second surface is coated with an anti-reflection coating, so this is not so terribly important. When you see some one use a 2 degree wedge it is almost always because they are using an uncoated prism to do the splitting. These are convenient general purpose lab tools because you don't have to have a specific coating for a specific purpose, you don't have to use them at a specific angle, you can use them at all wavelengths that the material transmits, and you can tailor the ratio of the split and to some degree the polarization by paying attention to the Fresnel coefficients. Uncoated wedges are also cheap. The penalty is that you can't get a strong reflected beam. They also don't generally have an anti-reflective coating on the second surface. This would kind of constrain the general utility. Instead they are wedged so the second surface reflection can be discarded.
If you need equal strength beams, you will need an optical coating designed for 50-50 polarization independent (mostly) splitting and a specific angle of incidence (usually 45 degrees). Such a beam splitter will also generally have an anti-reflective coating on the second surface, so you won't care much whether or not it is wedged, and it is usually more convenient if it isn't (no deviation of the transmitted beam). Alternatively, you can use an uncoated wedge and attenuate the transmitted beam to make the intensities equal.
Actually, I shouldn't say that you CAN'T get a 50-50 split with an uncoated wedge. At high angles of incidence you can choose an angle where one polarization or the other splits 50-50. You can also choose a place where unpolarized light splits 50-50 by net intensity although the two beams will not have the same resulting polarization.
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