Tuesday, 31 December 2013

rainbow reflections

Colours of light have different wavelengths. If a repeating structure has the same length as the light's wavelength, then that light can be reflected. In this picture, a liquid crystal whose structure varies across the image allows different colours of light to pass through, resulting in this rainbow-like picture.

Tuesday, 17 December 2013

finger prints

A lot of the images on here, including the zoomable images, can be viewed and downloaded at full resolution from my flickr: Ben's liquid crystal photography on flickr. Please use these images for educational and non-commercial purposes only.

Liquid crystals are a fluid, but have some properties that crystals have. They are structurally ordered, unlike isotropic ('normal') fluids like water. This means they can interact with light to produce patterns like what you see here when you use filters to see what's happening to the direction of the light polarization state (i.e. which direction the light's fields are wiggling). This particular example has a gradient across the cell in the concentration of an asymmetric additive, resulting in the structure changing how much it likes to twist in a spiral. You can't see the spiral itself, only the effect on the light passing through. Since a spiral has a periodic structure that repeats itself, the result is a periodic stripy pattern that you can see here. It's sometimes called a 'finger print' texture.

Saturday, 14 December 2013

deep zoom liquid crystal images part 2

Please maximise the image below to fill your screen. The image has been stitched together from hundreds of polarizing microscope photographs. It shows a 'liquid crystal cell', or two pieces of glass separated by 10 microns (10 millionths of a meter) and filled with liquid crystal. The cell is approximately a centimetre wide.

Several different types of liquid crystal have been filled into the cell, in order to make it look pretty! Can you tell me what you think is going on?

There is an artefact at the bottom where the computer program was unable to stitch the images properly together. If you have experience and would like to do a better job than me at stitching, please get in touch and I can send you the source images!

rotating polarizers

The below animated gifs show what happens as you rotate one of the polarizers in the polarizing microscope around 360 degrees.

deep zoom liquid crystal images part 1

Please expand the below zoomable image to fill your screen. These ultra-high resolution images of liquid crystals, taken using polarizing microscopy, have been compiled from multiple images and digitally stitched together. The colours that you see are the same as what you would see down the microscope with your own eyes!

This blog will explore some of the natural beauty and science of liquid crystals.

The image above is taken with a 10X lens, and the below image shows the top part of the above image at an even higher resolution, using a 50X lens, so you can see even finer detail.