In microscopy when using a stereo microscope it is common to use a LED ring light for illumination. You may have noticed that LED ring lights are available with polarization. What exactly is a polarizing LED ring light and why would you want one?

What is a Polarizing LED Ring Light?

A polarizing LED ring light is used to reduce glare on metallic samples. The polarized LED ring light has both an analyzer and a polarizer that can be cross-polarized. The analzyer sits inside the center of the ring light, while the polarizer is built into the body and can be rotated.

When using the polarizing LED ring light, as the polarizer is rotated at different angles, glare from metallic parts and reflections are reduced. This feature makes the polarizing LED ring light very attractive if viewing circuit boards, metallic objects or parts such as copper that might produce a lot of extra glare and make it hard to view imperfections in the samples.

In order to show some of the differences between a standard LED ring light and a polarizing LED ring light, Microscope World captured images of a circuit board with each illuminator.

This image of a circuit board was captured under a stereo microscope using a camera with extended depth of focus software and a standard LED ring light.

Above is the same circuit board captured under the stereo microscope using the same camera with extended depth of focus software and a polarizing LED ring light. Notice the difference in glare on the circuit components.

This circuit board image was captured under the stereo microscope using the polarizing LED ring light. You will notice in the next image that the numbers appear a bit more crisp.

The crispness of the numbers on this circuit board image were obtained by rotating the polarizer  on the LED ring light to get cross polarization.

This circuit board image was captured with a standard LED ring light. The image below is the same circuit board using the polarizing LED ring light.

If you have any questions about polarized light microscopy or choosing a ring light for your stereo microscope contact Microscope World.