[Jimee]

I'm not sure which area is best to potentially get some help on this question so if someone can help (with the question or with the area to post a question) I would be grateful.

The problem: I would like to find a substance which is affected by 1 or more bands of light But not heat.  When I say affected, I am thinking along the lines of shrinking or expanding when a light source is detected.  Ideally it should be a relative reaction - in that the stronger the light source the more reaction garnered.

Let me give you an example:
Certain plants are chemically affected by light and are actually able to track the sun as it moves across the sky.  This is generally done by an expansion of a fluid on one side or the other of the plant - i.e. causing the stem to distort based on relative pressures generated.  I believe that this increased pressure is actually caused from one or more bands of light - not heat.

I essentially want to mimic this action on a flexible fiber optic cable (or wire - more specifically on individual fiber optic wires).

Therefore,

Here's my wish list:
Find a substance that can be applied (attached or coated) on a fiber optic wire and will potentially create physical distortions when a light source is detected.

[AhmedEzatAlzawalaty]

i think you have to extract that fluid from sunflower and coat the fiber with it.