I'm trying to design a metal surface with micro-perforation for a product and light it from other side with LED, such that the perforated pattern appears only when lit.
In my previous prototype, which used laser drilling (20 micron holes) for perforation, there was considerable warping of the metal film (around 0.3 mm thick) which rendered the prototype unusable (aesthetically)
Another problem I had with the prototype was that the light was not getting through perforation evenly i.e., I was not able to see the light from different angles.
On initial research about laser micro-drilling I found that the thermal conductivity of material plays important role in heat affected zone, which could result in warping. The material used for prototype was stainless steel, which has comparably lower thermal conductivity than aluminium.
- What care needs to be taken to avoid or reduce the HAZ and hence the warping?
- For the visibility of light through perforation, will the hole size and spacing directly affect this?
I am trying to achieve the appearance like shown below
Misfit Shine fitness band; the micro-perforation on dial is invisible when unlit.