http://www.goiit.com/posts/list/magnetism-in-polarizer-analyzer-combination-90-of-the-light-1093138.htm

When discussing the interaction of light with polarizers and analyzers, particularly in the context of magnetism, it's essential to grasp the fundamental principles of polarization and how these devices manipulate light. Let's break this down step by step.

Understanding Polarization

Polarization refers to the orientation of light waves. Natural light consists of waves vibrating in multiple directions. When light passes through a polarizer, it filters out all but one orientation of these waves. For example, if you have a vertical polarizer, it will only allow light waves vibrating in the vertical direction to pass through.

The Role of Analyzers

An analyzers function similarly to polarizers, but they are used to determine the polarization state of light. When polarized light encounters an analyzer, it can either pass through or be blocked, depending on the angle between the light's polarization direction and the analyzer's orientation.

Combining Polarizers and Analyzers

When you place a polarizer and an analyzer in sequence, the amount of light that passes through depends on their relative orientations. If the polarizer is set at 0 degrees and the analyzer at 90 degrees, no light will pass through because the two orientations are perpendicular to each other. This is a fundamental principle of how polarizers work.

Magnetism and Light Interaction

Now, let's introduce the concept of magnetism. In certain materials, the presence of a magnetic field can affect the polarization of light. This phenomenon is known as the Faraday effect. When light travels through a material in the presence of a magnetic field, its polarization plane rotates. This rotation can be used to analyze the properties of the material or the strength of the magnetic field.

Practical Example

• Setup: Imagine you have a vertical polarizer followed by a horizontal analyzer.
• Observation: If you shine unpolarized light through the polarizer, it becomes vertically polarized. When this light hits the horizontal analyzer, it is completely blocked.
• With Magnetism: If you introduce a magnetic field in the medium between the polarizer and analyzer, the polarization of the light can rotate. Depending on the strength of the magnetic field, some light may now pass through the analyzer, demonstrating the interaction between light and magnetism.

Conclusion

The interplay between polarizers, analyzers, and magnetism illustrates fundamental principles of optics and electromagnetism. By manipulating the orientation of light waves and understanding how magnetic fields can influence these waves, we can gain deeper insights into both light behavior and material properties. This knowledge is not only crucial in physics but also has practical applications in various technologies, including optical devices and sensors.