Butterfly Scales

Butterflies have been known around the world for their iridescence. This trait has been used in technologies such as Mirasol displays to increase efficiency within battery power. I have explained this before within a previous post, but these photographs explain the phenomenon in a far more visually engaging way. 

These are the scales of Regina de bambiri at a 10x magnification through a microscope. This species does not have the iridescence of a Morpho butterfly, but this photograph shows the scaled structure that makes up the colour of the butterfly.

Here is a 20x magnification of the scales, showing the actual shape of these overlapping structures.

Here, another species of butterfly is seen with a similar structure, this time lit from the surface instead. This is designed to be a more artistic shot, showing the almost bone/feather support helping hold the wing together. This was shot on a 10x magnification.

Again, this shows another non-iridescent species (Cethosia myrina sandora). This was shot on a 10x magnification.

This is where the Morpho butterfly comes into play. Lighting the scales from underneath, you can see the shape of the scales that are similar to the top photographs of Regina de bambiri, but this time (with a little more light being shone onto the top of the subject) you can see the colour created by the nanostructure of the scales. Without this top lighting, the blue scale effect does not appear. 

Whilst looking at the Morpho under a microscope, I couldn't resist taking a few shots of the compound eye of these magnificent creatures. 38 to be exact. After stacking these shots, here is the final outcome.

Again here is another example of the eye of a butterfly, this time it was the A. adamsi butterfly. This shot was intended to be more artistic and abstract to the rest. All of these images were shot through a Zeiss microscope at university using a mounted D300 body.

Wasps

Following with the macro trend, I've started using all manner of insects to practise lighting with. Yesterday I shot a wasp found in the back of a friends car which was gladly in tact. Here are the results, but I am hoping to build a setup which will be more effective in the next week or so.

The first shot was photographed using a vivid setting on JPEG format, reducing the amount of strain put onto my computer when stacking them. Unfortunately it's made the eyes very high in contrast, shadowing some of the detail within the eye.

'Butterfleyes'

Yesterday I was in the studio shooting some butterflies, and please do excuse the pun title. In this post I'll explain the shoot, species and reason behind scientists finding these species so interesting. 

I took these photographs of the butterflies eyes because I need to shoot a moths eye soon for another technology. I see this as a practise run, but was happy with the results. The top photograph is comprised of 17 photos, the middle has over 30 and the bottom is made up of 11. The scales shot in the middle is of the Morpho, but is only a test shot. The real photograph will be taken soon under a microscope, as this just looks like a messy blur at the moment, and it's hard to distinguish any real detail. 

Photonic crystals are precise arrangements of geometrical patterns at microscopic scales. 

On butterfly wings, these patterns might be bumps, holes, ridges, hexagonal arrays or other shapes, often in 3-D arrangements. The shapes are spaced very close to the wavelengths of light in ways that intensify the reflected light of certain colors and absorb others. You’ve seen this effect in the colors in oil on water -- depending on the angle, some colors become vivid -- except in the case of butterflies, the effect is controlled by the genetic code for purposes such as species recognition, mating display, warnings to predators, and camouflage. The control is so effective that the colors can be seen from a wide range of angles, even when the butterfly is flapping its wings in flight. The iridescent blue of the Morpho butterfly (seen here to the left) uses this technique, while and the oranges and yellows of the Monarch are produced by pigments.

In other words, the shape and arrangement of these scales mess around with light so much that in theory, you could create different spectrums of colour by changing these shapes and arrangements. I photographed these two butterflies, the top being a Morpho (which I bought online) and the latter being an Ornithoptera Croesus (commonly known as Wallace's Golden Birdwing) which I found in one of the studios at university. 

These can then be utilised within technology by creating brighter clothing, sensors that change colour with shape, more visible safety equipment and maybe one day even brighter teeth. A company called Mirasol have used this concept within flat screens to create a reflective membrane which increases battery life by 40%. 

At the most basic level, a mirasol display is an optically resonant cavity. The device consists of a self-supporting deformable reflective membrane and a thin-film stack (each of which acts as one mirror of an optically resonant cavity), both residing on a transparent substrate.

When ambient light hits the structure, it is reflected both off the top of the thin-film stack and off the reflective membrane. Depending on the height of the optical cavity, light of certain wavelengths reflecting off the membrane will be slightly out of phase with the light reflecting off the thin-film structure. Based on the phase difference, some wavelengths will constructively interfere, while others will destructively interfere. 

The human eye will perceive a color as certain wavelengths will be amplified with respect to others. The image on a mirasol display can switch between color and black by changing the membrane state. This is done by applying a voltage to the thin-film stack, which is electrically conducting and is protected by an insulating layer. When a voltage is applied, electrostatic forces cause the membrane to collapse.