Constructing a Liquid Mirror using gallium,Indium, tin alloy

In summary, the artist is looking for advice on making a liquid mirror. The artist has made a polyester resin parabola and is using a gallium, indium, tin alloy to make the mirror. The artist has some issues with the mirror, including surface scum and the fact that most of the alloy rolls back into the center of the resin container. The artist is looking for advice on how to fix the issues.
  • #1
I am an an artist hoping that you scientists can kindly help me with some advice.
I am making a simple liquid mirror as part of a project about reflected image. It will spin and stop and spin and stop etc.
I have made a polyester resin parabola as a receptical (so that I can use less alloy) and am spinning it on a record player (for testing). I am using a gallium, indium, tin alloy as, in uk, it is by far cheaper than gallium indium or simply gallium.
It kind of works but not perfectly. Firstly, almost a thin scum seems to gather on the surface whereas I am looking for a real mirror finish. Is that the tin element or would it work like that even with pure gallium? Secondly, when I stop the spin, most of the alloy rolls back into the centre of the resin container. I had (perhaps niavely) expected it all to roll back rather than have a layer cling to the sides. I would be very grateful for any advice you can offer?
Science news on
  • #2
From what little I know of liquid mirrors, the real 'art' (sorry..) is maintaining the rotation rate perfectly constant: any high frequency jitter will result in surface waves, destroying the optical figure.

In terms of the surface scum- it's most likely contamination- AFAIK, the solution is to regularly scrape off that layer (this was true for Hg mirrors). Material that 'clings' to the resin is probably wetting the resin- I don't know enough of the relevant chemistry to suggest a surface treatment, tho.
  • #3
Well I also know very little about liquid mirrors, but what I found about Galinstan it is really sticky and adhere to almost anything. To prevent it the surface has to be treated with gallium oxide (maybe there other treatments, but i do not know).
About that scum - From what i have seen it resmbles colling tin so maybe higher temperature might help. But i do not know if it is safe to heat Galinstan so check it first.

Related to Constructing a Liquid Mirror using gallium,Indium, tin alloy

What is a liquid mirror and how is it constructed?

A liquid mirror is a reflective surface made of a thin layer of liquid metal. It is constructed by melting a specific alloy, typically gallium, indium, and tin, and spinning it at a high speed to create a parabolic shape. This shape allows for the liquid metal to act as a mirror, reflecting light just like a traditional glass mirror would.

Why use gallium, indium, and tin for a liquid mirror?

These three metals have low melting points and are relatively inexpensive, making them ideal for creating a liquid mirror. Additionally, they have the right properties to create a highly reflective surface when spun at high speeds.

What are the advantages of a liquid mirror over a traditional glass mirror?

Liquid mirrors are much lighter and more cost-effective to construct compared to glass mirrors. They also have a larger surface area, making them useful for larger telescopes and other optical devices.

What are the limitations of a liquid mirror?

One major limitation of a liquid mirror is that it can only be used in a fixed, upright position due to the effects of gravity on the liquid metal. It also requires a constant rotation to maintain its shape and reflectivity, making it unsuitable for use in handheld devices.

What are the potential applications of a liquid mirror?

A liquid mirror can be used in various optical devices, such as telescopes and cameras, to capture and reflect light. It can also be used in solar power generation, as the reflective surface can focus sunlight onto a solar panel. Additionally, liquid mirrors can be utilized in adaptive optics technology for better image resolution in astronomy and other fields.

Similar threads

  • Materials and Chemical Engineering